Guest guest Posted July 1, 2002 Report Share Posted July 1, 2002 Dear Group, Anyone taking Prozac, or any other SSRI, and the weather is warm, must be very careful not to overheat. The body's ability to cool its core temperature is damaged. noticed that there is a HOT MED policy in place where those on Prozac and the like are restricted to air-conditioned rooms when the temp approaches 90 degrees. Here is the reason why: Ann N Y Acad Sci 1997 Mar 15;813:553-8 Related Articles, Books, LinkOut Heat intolerance induced by antidepressants. Epstein Y, Albukrek D, Kalmovitc B, Moran DS, Shapiro Y. Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. A case in which prescription medications induced heat intolerance which led to heat stroke is presented. A subject who suffered from depression and was treated with fluoxetine HCL (prozac) and lithium carbonate was engaged in mild intermittent work for 4 hours under hot/dry climatic conditions (Ta = 37 degrees C, rh = 15%). The subject lost consciousness, was hyperthermic and suffered from disseminated intravascular coagulation. A year later residual cerebellar symptoms were still evident and severe atrophy of the cerebellar tissue was demonstrated in a CT scan. It is suggested that drug-induced heat intolerance was the predisposing factor that reduced the patient ability to sustain exercise-heat stress, and under the favorable environmental circumstances led to excessive heat accumulation which ultimately caused heat stroke. This is the first description, to our knowledge, of heat intolerance of a patient treated by a combination of fluoxetine and lithium carbonate. PMID: 9100934 [PubMed - indexed for MEDLINE] Hosp Community Psychiatry 1982 Jun;33(6):474-6 Related Articles, Books, LinkOut The prevention and treatment of heatstroke in psychiatric patients. Bark NM. Heatstroke is a serious medical condition that affects people in all climates. There is some preliminary evidence that psychiatric patients and those on psychotropic drugs are particularly susceptible. The author discusses the signs and symptoms of heatstroke, the factors that lead to it, and the appropriate preventive and treatment measures that should be taken. He concludes that heatstroke in psychiatric patients is totally preventable, but that should heatstroke occur, quick recognition and treatment can prevent death. PMID: 6124500 [PubMed - indexed for MEDLINE] Am J Psychiatry 2000 Aug;157(8):1327-9 Related Articles, Books, LinkOut Heat intolerance in patients with chronic schizophrenia maintained with antipsychotic drugs. Hermesh H, Shiloh R, Epstein Y, Manaim H, Weizman A, Munitz H. Geha Psychiatric Hospital, Petah Tiqva, Israel. hermesh@... OBJECTIVE: Schizophrenia may be associated with hyperthermic syndromes such as febrile catatonia, neuroleptic malignant syndrome, and heatstroke. The authors hypothesized that an exercise-heat tolerance test would disclose abnormal thermoregulation in schizophrenic patients. METHOD: Seven male schizophrenic outpatients in remission maintained on depot antipsychotic treatment and eight healthy comparison subjects completed a heat tolerance test that consisted of two 50-minute bouts of walking a motor-driven treadmill at 40xC (relative humidity=40%). RESULTS: A significantly higher rise in rectal and skin temperatures was observed in the patient group. No differences in heart rate, blood pressure, or perspiration were detected. CONCLUSIONS: Schizophrenic patients maintained on antipsychotic drugs exhibit impaired heat tolerance. Possible explanations are a reduced ability to convey heat from the body's core to the periphery with or without excessive heat production. The hyperthermic response to the heat tolerance test may reflect a dysfunction associated with schizophrenia, a neuroleptic-induced side effect, or both. PMID: 10910799 [PubMed - indexed for MEDLINE] Lancet 1996 Apr 13;347(9007):1016 Related Articles, Books, LinkOut A depressed workman with heatstroke. Albukrek D, Moran DS, Epstein Y. IDF Medical Corps, Institute of Military Physiology; and Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. PMID: 8606565 [PubMed - indexed for MEDLINE] Prog Brain Res 1998;115:193-204 Related Articles, Books, LinkOut The effects of drugs on thermoregulation during exposure to hot environments. Lomax P, Schonbaum E. School of Medicine, University of California, Los Angeles 90024, USA. Publication Types: Review Review, Tutorial PMID: 9632937 [PubMed - indexed for MEDLINE] Ned Tijdschr Geneeskd 1995 Jul 8;139(27):1391-3 Related Articles, Books, LinkOut Comment in: • Ned Tijdschr Geneeskd. 1996 Feb 17;140(7):388. [Psychiatric drugs as risk factor in fatal heat stroke] [Article in Dutch] Fijnheer R, van de Ven PJ, Erkelens DW. Afd. Interne Geneeskunde, Academisch Ziekenhuis, Utrecht. Two men aged 33 and 31 years suffered a fatal heat stroke on a warm summer day. One of them used pimozide and clomipramine, the other zuclopenthixol, dexetimide, droperidol, promethazine and propranolol as psychiatric medication. Both of them had a body temperature > 42.3 degrees C, without perspiring. At first only a comatose situation with practically normal laboratory values existed; this was rapidly followed by massive liver damage, disseminated intravascular coagulation, anaemia, thrombopenia and acute renal failure. In spite of adequate and rapid treatment these complications were fatal. Both patients used medication with an antidopaminergic and anticholinergic (side) effect. The set point of the temperature regulation centre can be elevated by the antidopaminergic activity of antipsychotics. Use of anticholinergic medication can disturb the thermoregulation via inhibition of the parasympathicomimetically mediated sweat secretion. It is recommended to point out the danger of unusually high outdoor temperatures to patients using this medication. PMID: 7617062 [PubMed - indexed for MEDLINE] : Ned Tijdschr Geneeskd 1995 Aug 26;139(34):1759-60 Related Articles, Books, LinkOut Comment on: Ned Tijdschr Geneeskd. 1995 Jul 8;39(27):1391-3 [Psychiatric medication as risk factor for fatal heat collapse] [Article in Dutch] Conemans JM. Publication Types: Comment Letter PMID: 7566248 [PubMed - indexed for MEDLINE] Chest 1981 Aug;80(2):244-5 Related Articles, Books, LinkOut Heat stroke related to psychotropic medications and prior history of heat stroke. Caldroney RD. Publication Types: Letter PMID: 7249779 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1983 Feb;46(2):183-5 Related Articles, Books, LinkOut Cerebellar syndrome following neuroleptic induced heat stroke. Lefkowitz D, Ford CS, Rich C, Biller J, McHenry LC Jr. We report a patient in whom extreme hyperthermia, rhabdomyolysis, acute renal failure and a residual pancerebellar syndrome occurred while taking a combination of perphenazine and amitriptyline. We postulate that impaired thermoregulation due to psychotropic drugs was responsible for the development of heat stroke and that the cerebellar syndrome resulted directly from the elevated temperature. PMID: 6842224 [PubMed - indexed for MEDLINE] Minn Med 1977 Feb;60(2):103-6 Related Articles, Books, LinkOut Heat stroke associated with medications having anticholinergic effects. BE, Manoguerra AS, Lilja GP, Long RS, Ruiz E. PMID: 840206 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1987 Jul;50(7):937-8 Related Articles, Books, LinkOut Heat stress and neuroleptic drugs. Tacke U, Venalainen E. Publication Types: Letter PMID: 2887638 [PubMed - indexed for MEDLINE] J Clin Psychiatry 1982 Sep;43(9):377-80 Related Articles, Books, LinkOut Heatstroke in psychiatric patients: two cases and a review. Bark NM. Two fatal cases of heatstroke in psychiatric patients are described. A literature search revealed published reports of heatstroke involving 51 psychiatric patients, 22 of whom died. The mean age of these patients was 44 years; the majority has schizophrenia. Almost all were male and were taking antipsychotic or other drugs with anticholinergic effects. The implications for prevention, recognition, and treatment are discussed. PMID: 6126476 [PubMed - indexed for MEDLINE] Ann Anesthesiol Fr 1979;20(8):709-16 Related Articles, Books, LinkOut [Heatstroke among psychiatric patients under neuroleptic therapy. Apropos of 2 fatal cases] [Article in French] Ducrot P, Jouan JC, Sala JP, Mathon J. Heat stroke is uncommon in temperate climates but may be favourised by drug treatment. A report of two cases of fatal hyperthermia occuring in patients treated with neuroleptic drugs and during a heat wave is followed by a discussion of the characteristics which may be used to differentiate heat stroke from the hyperthermia of malignant twenty cases. It indicated that high degree of severity of this type of heat stroke, in great part related to the high prevalence of massive inhalation. The action of neuroleptics is very probably central by an effect upon the thermostat and also by changes in behaviour. The role of associated anti-parkinsonian agents is discussed. A review of treatment emphasises its difficulties. Publication Types: Review PMID: 44988 [PubMed - indexed for MEDLINE] 1: Gen Hosp Psychiatry 1985 Oct;7(4):361-3 Related Articles, Books, LinkOut Heatstroke in a chronic schizophrenic patient treated with high-potency neuroleptics. Lazarus A. A fatal case of heatstroke occurred in a chronic schizophrenic patient treated with high-potency neuroleptics. The author differentiates heatstroke from other hyperthermic syndromes related to treatment with major tranquilizers and suggests that an awareness of factors that predispose psychiatric patients to the development of heatstroke may aid in its prevention. PMID: 2866145 [PubMed - indexed for MEDLINE] Pitt DC, Kriel RL, Wagner NC, Krach LE. Related Articles Kluver-Bucy syndrome following heat stroke in a 12-year-old girl. Pediatr Neurol. 1995 Jul;13(1):73-6. PMID: 7575855 [PubMed - indexed for MEDLINE] Pediatr Neurol 1987 May-Jun;3(3):162-5 Related Articles, Books, LinkOut Kluver-Bucy syndrome in children. Tonsgard JH, Harwicke N, Levine SC. Department of Pediatrics, University of Chicago, IL 60637. Kluver-Bucy syndrome is an uncommon syndrome of behavioral abnormalities following bilateral temporal lobe injury. Only four children have been reported previously with this syndrome. We report three additional pediatric patients who developed Kluver-Bucy syndrome following hypoxic insults. In two patients, features of the syndrome were transient. Problems in intermediate memory were present in each patient. Behavioral abnormalities did not respond to the medications administered. Our experience suggests that Kluver-Bucy syndrome may occur more commonly in children than was suspected previously, especially following hypoxia. PMID: 3508062 [PubMed - indexed for MEDLINE] J Neurosurg Sci 1997 Sep;41(3):269-72 Related Articles, Books, LinkOut The Kluver-Bucy syndrome. Goscinski I, Kwiatkowski S, Polak J, Orlowiejska M, Partyk A. Jagiellonian University, Medical Faculty, Department of Neurotraumatology, Krakow, Poland. Evolution of psychological disorders following head injury including memory disorders and other cognitive ones are common. The best known are psychiatric disturbances of various kind after lesions of frontal lobes. Cognitive, behavioural and emotional disorders are not usually seen in patients with bilateral temporal lesions. In our Department of Neurotraumatology we observed 4 patients with post-traumatic lesions localized bitemporally. They developed Kluver-Bucy syndrome--rarity in human pathology--with combination of three or more the following syndromes: increased oral activity, hypersexuality, hypermetamorphosis, memory disorders, placidity, loss of people recognition, bulimia. Several symptoms responded dramatically to carbamazepine. We conclude that it may be a useful agent in treatment of this unusual syndrome. PMID: 9444580 [PubMed - indexed for MEDLINE] Am Fam Physician 1998 Sep 1;58(3):749-56, 759 Related Articles, Books, LinkOut Heat-related illnesses. Barrow MW, KA. State University School of Medicine, Dayton, Ohio, USA. Heat-related illnesses cause 240 deaths annually. Although common in athletes, heat-related illnesses also affect the elderly, persons with predisposing medical conditions and those taking a variety of medications. Symptoms range from mild weakness, dizziness and fatigue in cases of heat edema, to syncope, exhaustion and multisystem complications, including coma and death, in cases of heat stroke. Milder heat-related symptoms can be treated with hydration, rest and removal from the hot environment. Heat stroke, a life-threatening problem, must be treated emergently. Prompt recognition is critical since rapid cooling is the cornerstone of treatment and must not be delayed. Fluid resuscitation with dextrose and normal or half-normal saline is also important. These therapies should be instituted while the patient is being stabilized. Heat illness may be prevented by recognizing which individuals are at risk, using appropriate hydration and paying attention to acclimatization and environmental conditions. Preventive care should include drinking plenty of fluids before, during and after activities, gradually increasing the time spent working in the heat and avoiding exertion during the hottest part of the day. Publication Types: Review Review, Tutorial PMID: 9750542 [PubMed - indexed for MEDLINE] http://abcnews.go.com/sections/living/Healthology/heatwave_dangers.html Heat Wave Dangers A. Finkel, MD, Massachusetts General Hospital Most often, heat-related illnesses are preventable conditions. However, they can have significant consequences, including death, if left untreated. The illnesses are traditionally divided into two main categories-heat exhaustion and heat stroke. These conditions can overlap in many ways and exist on a continuum of severity. As a patient's body temperature rises, heat exhaustion can rapidly progress to heat stroke. Heat Exhaustion and Heat Stroke Heat exhaustion develops when the body encounters excessively high temperatures that it is not used to managing. It occurs at body temperatures that are very high, but usually less than 40 degrees Celsius, or 104 degrees Fahrenheit. The symptoms of heat exhaustion are not very specific, but ultimately relate to a state of dehydration, which is the condition's primary characteristic. Symptoms may include weakness, headache, and nausea. Heat stroke is severe injury from high body temperatures that causes damage to many organs, particularly the central nervous system, which include the brain and spinal cord. In contrast to heat exhaustion, patients suffering from heat stroke will have temperatures that are usually greater 104 degrees. Heat stroke may be divided into two categories-exertional and classic. Exertional heat stroke Exertional heat stroke patients are usually people who are exercising in excessively warm conditions. Their bodies cannot manage the stress of the physical activity and the hot environment together. Classic heat stroke Classic heat stroke patients are often elderly or debilitated people who are in warm environments for too long. The elderly are especially vulnerable to the heat, as the body is less and less able to handle heat as it ages. Elderly people may also have pre-existing illnesses that make them more susceptible to heat stroke, or they make take medications that affect the body's ability to manage hot temperatures. Elderly people, who, for economic reasons, are not able to get out of the heat, are at great risk for heat stroke. Heat Transfer In order to understand heat-related illnesses you need to know something about the way the body normally gets rid of heat. There are four ways the body transfers heat: radiation, evaporation, conduction, and convection. Radiation Radiation occurs when the body turns heat into electromagnetic waves. In other words, waves of heat can escape from the body directly into the surrounding air. This is the primary way that human beings are able to lose heat from their bodies in very hot environments. Evaporation Evaporation is the transfer of heat that occurs during the transformation of liquid to gas. Evaporation of sweat (even of sweat you cannot feel, called insensiblelosses) is another significant method that the body uses to cool down. Convection and conduction Convection and conduction are secondary ways for the body to lose heat after radiation and evaporation. Convection is the passage of heat into the air and into the vapor that surrounds the body. It is different from evaporation in that the heat does not transform to the gas phase, as it does in evaporation. Conduction is the transfer of heat through physical contact. What Happens When it Gets Too Hot In hot environments, the body initiates several processes to lose heat. First, the anterior hypothalamus, the body's thermostat in the brain, signals the body to open up blood vessels near the skin's surface so that heat can be transferred outside by the methods listed above. This vessel dilation is possible because blood is shunted away from the body's core. The hypothalamus also mediates sweating and tells the body to respond to the heat by taking off clothes and seeking a cooler environment. When it becomes too hot, however, the body's ability to cool down becomes overwhelmed. Symptoms like fatigue, headache, muscle aches, confusion, and even coma can occur, depending on the severity of the condition. This overwhelming of the body's means of handling heat can be caused by a very warm environment or excessive exercising in the heat, as discussed before. Also, though, patients may get overheated because of certain illnesses like hyperthyroidism (high thyroid hormone level) or infections causing fever. Additionally, some medications can cause high body temperatures. A class of drugs called anticholinergics can decrease the body's ability to sweat and, therefore, to lose heat. Other drugs called sympathomimetics can decrease skin vessel dilation. There are other classes of drugs that may also interfere with body temperature regulation through various, sometimes complicated, mechanisms. Symptoms and Signs There are a variety of symptoms associated with heat-related illnesses. Heat exhaustion patients may have vague complaints of symptoms that come on slowly. These can include: • Headache • Weakness • Lightheadedness • Muscle aches • Muscle cramps • Agitation Heat stroke patients can have the same complaints as heat exhaustion patients, but they also suffer central nervous system problems, which can include: • Confusion hallucinations • Bizarre behavior • Seizure • Coma It was once thought that heat stroke patients did not sweat, but this inability to sweat is variable, and often strikes the patient at the latest stages of the condition. Heat stroke patients, because of the resulting multi-organ damage, may also complain of blood in the urine or stool, decline in the amount of urine produced and shortness of breath, among other problems. Other symptoms There are secondary categories of heat-related illnesses to watch out for: • Heat syncope occurs when a person overheats and then faints. • Heat cramps are muscle contractions associated with electrolyte or mineral abnormalities caused by the heat. • Heat edema is characterized by swelling in the arms and legs because of the heat. • Prickly heat is a heat rash that is red and very itchy. Treatment There is a lot that you can do for a person suffering from a heat-related illness. If you see someone who appears to be suffering from a heat-related illness, you should call for help immediately. In the most rare, severe cases, you should start cardiopulmonary resuscitation (CPR), if necessary. If the person is not a trauma patient (has not been in an accident, fight, or fall), you should move the individual from the hot environment to a cooler location. Next you can sprinkle lukewarm water on the skin and fan the patient; this will encourage evaporation. You can also apply ice packs to the neck, underarms, and groin. In the emergency room Once a patient has been taken to the emergency room, the cooling process will be continued. The doctor may use a cooling blanket and some other more aggressive methods, but in general, treatment is similar to the methods that should be initiated immediately, including fanning and ice packs. The doctor may order tests to assess organ damage. These tests can include electrolytes or minerals, blood-clotting tests, a urine analysis, creatine phosphokinase (a muscle enzyme quantification), and a head computed tomography (CT or cat) scan. Heat stroke patients are admitted to the intensive care unit. Heat exhaustion patients are admitted to a regular floor bed in the hospital. When patients are released from the hospital, they should have a place to go to avoid the heat, and they must be able to rehydrate themselves. If caretakers are aggressive with these cooling techniques before delivering the patient to the hospital, and the emergency department is able to treat any related organ damage, then there is a good possibility that the prognosis will be excellent. Prevention Heat-related illnesses are often preventable. When hot weather is expected, the elderly and debilitated must be ensured access to cool, air-conditioned shelter. People should be encouraged to wear light-colored, loose clothing and bathe in tepid water. Also, hydration is critical, and people in hot weather should increase their fluid intake substantially. To avoid exertional heat stroke, athletes should not exercise in extreme heat, and coaches should be aware of the symptoms of heat-related illnesses. Athletes also must stay well-hydrated. Summary Heat-related illnesses are a continuum of conditions but have traditionally been divided into heat exhaustion-characterized by dehydration-and heat stroke, in which organs, particularly the central nervous system, are damaged. Heat exhaustion patients may have vague complaints like weakness, nausea and headache, whereas heat stroke patients often have these symptoms plus confusion or hallucinations. Heat-related illnesses present a potentially severe-even fatal-set of conditions that can often be prevented if treated early and aggressively. Learning about the symptoms and preventive care can help you help someone else. Can You Handle the Heat? Copyright 2001 Healthology, Inc. All rights reserved. This material may not be published, broadcast, rewritten or redistributed http://www.merck.com/pubs/mmanual/section20/chapter279/279b.htm Heatstroke (Sunstroke; Thermic Fever; Siriasis) Inadequacy or failure of heat loss mechanisms resulting in dangerous hyperpyrexia. Symptoms and Signs An abrupt onset is sometimes preceded by headache, vertigo, and fatigue. Sweating is usually decreased, and the skin is hot, flushed, and usually dry. The pulse rate increases rapidly and may reach 160 to 180 beats/min; respirations usually increase, but BP is seldom affected. Disorientation may briefly precede unconsciousness or convulsions. The temperature climbs rapidly to 40 to 41° C (104 to 106° F), causing a feeling of burning up. Circulatory collapse may precede death; after hours of extreme hyperpyrexia, survivors are likely to have permanent brain damage. Diagnosis and Prognosis Sudden development of hot, dry, flushed skin with a body temperature > 40° C (> 104° F), a rapid pulse, and confusion or unconsciousness in a person exposed to a hot environment are usually enough to distinguish heatstroke from food, chemical, or drug poisoning. An acute infection (eg, septicemia, meningitis) and toxic shock must be excluded. Drugs (see above) that may have precipitated the episode should be considered. 1998-2002 On-line Medical Dictionary http://cancerweb.ncl.ac.uk/cgi-bin/omd?query=disseminate & action=Search+OMD Article 1. Heat Intolerance Induced by Antidepressants Disseminate To scatter or distribute over a considerable area. (18 Nov 1997) intravascular Within a vessel or vessels. Origin: L. Vasculum = vessel (18 Nov 1997) coagulation 1. <haematology> The process of clot formation. 2. <chemistry> The solidification of a sol into a gelatinous mass, an alteration of a disperse phase or of a dissolved solid which causes the separation of the system into a liquid phase and an insoluble mass called the clot or curd. Coagulation is usually irreversible. 3. <surgery> The disruption of tissue by physical means to form an amorphous residuum, as in electrocoagulation and photocoagulation. Origin: L. Coagulatio (18 Nov 1997) Article 3. Heat Intolerance in Patients… Maintained with Antipsychotic Drugs “Patients maintained on antipsychotic drugs exhibit impaired heat tolerance.” febrile <symptom> Pertaining to or characterised by fever. Origin: L. Febrilis (18 Nov 1997) catatonia <neurology, psychiatry> A syndrome of psychomotor disturbances seen in schizophrenic disorders characterised by periods of either muscular rigidity, excitement or stupor. (16 Mar 1998) neuroleptic <pharmacology> A term coined to refer to the effects on cognition and behaviour of antipsychotic drugs, which produce a state of apathy, lack of initiative and limited range of emotion and in psychotic patients cause a reduction in confusion and agitation and normalisation of psychomotor activity. Origin: Gr. Lepsis = a taking hold (18 Nov 1997) malignant <oncology> Tending to become progressively worse and to result in death. Having the properties of anaplasia, invasion and metastasis, said of tumours. Origin: L. Malignans = acting maliciously (18 Nov 1997) heatstroke A severe and often fatal illness produced by exposure to excessively high temperatures, especially when accompanied by marked exertion. It can manifest by elevated body temperature, lack of sweating, hot dry skin, and neurologic symptoms; unconsciousness, paralysis, headache, vertigo, confusion. In severe cases very high fever, vascular collapse, and coma develop. Synonym: heat apoplexy, heat hyperpyrexia, malignant hyperpyrexia, thermic fever. (05 Mar 2000) vertigo <neurology, symptom> An illusion of movement, a sensation as if the external world were revolving around the patient (objective vertigo) or as if he himself were revolving in space (subjective vertigo). The term is sometimes erroneously used to mean any form of dizziness. Origin: L. Vertigo (18 Nov 1997) heat apoplexy -->heatstroke A severe and often fatal illness produced by exposure to excessively high temperatures, especially when accompanied by marked exertion. It can manifest by elevated body temperature, lack of sweating, hot dry skin, and neurologic symptoms; unconsciousness, paralysis, headache, vertigo, confusion. In severe cases very high fever, vascular collapse, and coma develop. Synonym: heat apoplexy, heat hyperpyrexia, malignant hyperpyrexia, thermic fever. (05 Mar 2000 apoplexy <clinical sign, neurology> Haemorrhage into the brain. A stroke. It is usually associated with loss of consciousness and paralysis of various parts of the body. (27 Sep 1997) hyperpyrexia <clinical sign> Exceptionally high fever either in comparison of the fever usually accompanying a particular disease or absolutely (as in heatstroke). (18 Nov 1997) thermic fever -->heatstroke A severe and often fatal illness produced by exposure to excessively high temperatures, especially when accompanied by marked exertion. It can manifest by elevated body temperature, lack of sweating, hot dry skin, and neurologic symptoms; unconsciousness, paralysis, headache, vertigo, confusion. In severe cases very high fever, vascular collapse, and coma develop. Synonym: heat apoplexy, heat hyperpyrexia, malignant hyperpyrexia, thermic fever. (05 Mar 2000) Article 6. Psychiatric Drugs as Risk Factor in Fatal Heat Stroke anaemia <haematology> Too few red blood cells in the bloodstream, resulting in insufficient oxygen to tissues and organs. Origin: Gr. Haima = blood (16 Dec 1997) thrombopenia -->thrombocytopenia <haematology> A decrease in the number of platelets in the blood, resulting in the potential for increased bleeding and decreased ability for clotting. Origin: Gr. Penia = poverty (18 Nov 1997) renal failure Chronic renal failure represents a slow decline in kidney function over time. Chronic renal failure may be caused by a number of disorders which include long-standing hypertension, diabetes, congestive heart failure, lupus or sickle cell anaemia. If renal function declines to a low enough level (end-stage renal disease) kidney dialysis may be necessary. A sudden decline in renal function may be triggered by a number of acute disease processes. Examples include sepsis (infection), shock, trauma, kidney stones, kidney infection, drug toxicity (aspirin or lithium), poisons or toxins (drug abuse) or after injection with an iodinated contrast dye (adverse effect). Both forms of renal failure result in a life-threatening metabolic derangement. (27 Sep 1997) “The set point of the temperature regulation centre can be elevated by the antidopaminergic activity of antipsychotics” antidopaminergic Preventing or counteracting (the effects of) dopamine. (18 Nov 1997) anticholinergenic <pharmacology> Refers to an agent that inhibits parasympathetic neural activity by blocking the neurotransmitter acetylcholine. Origin: Gr. Gennan = to produce (09 Oct 1997) parasympathetic Pertaining to a division of the autonomic nervous system. See: autonomic nervous system. (05 Mar 2000) acetylcholine <chemical, neurology, physiology> A chemical found in vertebrate neurons that carries information across the synaptic cleft, the space between two nerve cells. (06 May 1997) “It is recommended to point out the danger of unusually high outdoor temperatures to patients using this medication.” Article 9. Cerebellar Syndrome Following Neuroleptic Induced Heat Stroke cerebellar syndrome <syndrome> The signs and symptoms of cerebellar deficiency: dysmetria, dysarthria, asynergia, nystagmus, ataxia, staggering gait, and adiadochokinesia. (05 Mar 2000) dysmetria An aspect of ataxia, in which the ability to control the distance, power, and speed of an act is impaired. Usually used to describe abnormalities of movement caused by cerebellar disorders. See: hypermetria, hypometria. Origin: dys-+ G. Metron, measure (05 Mar 2000) hypermetria Ataxia characterised by overreaching a desired object or goal; usually seen with cerebellar disorders. Compare: hypometria. Origin: hyper-+ G. Metron, measure (05 Mar 2000) hypometria Ataxia characterised by underreaching an object or goal; seen with cerebellar disease. Compare: hypermetria. Origin: hypo-+ G. Metron, measure (05 Mar 2000) dysarthria <clinical sign, neurology> Imperfect articulation of speech due to disturbances of muscular control which result from damage to the central or peripheral nervous system. Origin: Gr. Arthroun = to utter distinctly (18 Nov 1997) asynergia Synonym: asynergy. Origin: G. A-priv. + syn, with, + ergon, work (05 Mar 2000) asynergy Lack of coordination among various muscle groups during the performance of complex movements, resulting in loss of skill and speed. When severe, results in decomposition of movement, wherein complex motor acts are performed in a series of isolated movements; caused by cerebellar disorders. Synonym: asynergia. (05 Mar 2000) nystagmus <neurology> An involuntary, rapid, rhythmic movement of the eyeball, which may be horizontal, vertical, rotatory or mixed, i.e., of two varieties. Origin: Gr. Nystagmos = drowsiness, from nystazein = to nod (18 Nov 1997) ataxia <neurology> Failure of muscular coordination, irregularity of muscular action. Origin: Gr. Taxis = order (16 Dec 1997) adiadochocinesis -->adiadochokinesis Inability to perform rapid alternating movements. One of the clinical manifestations of cerebellar dysfunction. See: dysdiadochokinesia. Compare: diadochokinesia. Synonym: adiadochocinesia, adiadochocinesis, dysdiadochokinesis. Origin: G. A-priv. + diadochos, successive, + kinesis, movement (05 Mar 2000) rhabdomyolysis <pathology> The destruction of skeletal muscle cells. Often the result of electrical injury, alcoholism, injury (or laying in one position for an extended period of time), drug side effects or toxins. (27 Sep 1997) Results for: pancerebellar 1 results found, sorted by relevance 1-1 THE MERCK MANUAL, Sec. 14, Ch. 179, Disorders Of Movement Disorders of the cerebellum and its inflow or outflow pathways produce deficits in the rate, range, and force of movement. ... size 26.0K Cerebellar And Spinocerebellar Disorders Disorders of the cerebellum and its inflow or outflow pathways produce deficits in the rate, range, and force of movement. Anatomically, the cerebellum has three subdivisions. The archicerebellum (vestibulocerebellum) comprises the flocculonodular lobe, helps maintain equilibrium and coordinate eye-head-neck movements, and is closely interconnected with the vestibular nuclei. The midline vermis (paleocerebellum) helps coordinate movement of the trunk and legs. Vermis lesions result in abnormalities of stance and gait. The lateral hemispheres, which make up the neocerebellum, control ballistic and finely coordinated limb movements, predominantly of the arms. Signs of cerebellar disease are listed in Table 179-3. STRUCTURAL LESIONS OF THE CEREBELLUM Articles 15 – 17. Kulver-Bucy Syndrome Following Heat Stroke Results for: Kluver-Bucy syndrome 621 results found, top 500 sorted by relevance 1-10 THE MERCK MANUAL, Sec. 14, Ch. 171, Delirium And Dementia lists many of the known causes of dementia. Dementia may occur at any age and can affect young people as the result of injury or hypoxia ... size 55.1K Dementia A chronic deterioration of intellectual function and other cognitive skills severe enough to interfere with the ability to perform activities of daily living. Complications Behavioral complications include hostility, agitation, wandering, and uncooperativeness. Psychiatric complications include depression, anxiety, and paranoid reactions. True psychosis (paranoia, delusions, and hallucinations) probably occurs in about 10% of patients with Alzheimer's disease. In addition, perhaps 80% of family members or caregivers develop depression over time. Metabolic problems (eg, dehydration, infection, drug toxicity) can worsen cognitive impairment and make patient management more difficult. Other complications include falls, incontinence, and confusion at dusk (sundowning). The drugs commonly used to treat Alzheimer's disease (especially antipsychotics for behavior disorders) can cause a parkinsonian movement disorder and orthostatic hypotension. Tricyclic drugs with anticholinergic side effects can cause constipation, urinary retention, glaucoma, and seizures. Nonprescription antihistamines can lead to worsened confusion. These complications put the patient at risk of premature institutionalization and should be avoided or quickly treated, because many can be controlled or reversed. Many drugs adversely affect the CNS, increasing confusion and lethargy. Sedatives, such as benzodiazepines, should be avoided when possible. Anticholinergic drugs, such as some tricyclic antidepressants, antihistamines, antipsychotics, and benztropine, should be avoided Article 18. Heat-Related Illnesses edema -->oedema <clinical sign> The presence of abnormally large amounts of fluid in the intercellular tissue spaces of the body, usually applied to demonstrable accumulation of excessive fluid in the subcutaneous tissues. Oedema may be localised, due to venous or lymphatic obstruction or to increased vascular permeability or it may be systemic due to heart failure or renal disease. Collections of oedema fluid are designated according to the site, for example ascites (peritoneal cavity), hydrothorax (pleural cavity) and hydropericardium (pericardial sac). Massive generalised oedema is called anasarca. Origin: Gr. Oide ma = swelling (18 Nov 1997) syncope <clinical sign> A temporary suspension of consciousness due to generalised cerebral ischaemia, a faint or swoon. (19 Jan 1998) Ann N Y Acad Sci 1997 Mar 15;813:553-8 Related Articles, Books, LinkOut Heat intolerance induced by antidepressants. Epstein Y, Albukrek D, Kalmovitc B, Moran DS, Shapiro Y. Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. A case in which prescription medications induced heat intolerance which led to heat stroke is presented. A subject who suffered from depression and was treated with fluoxetine HCL (prozac) and lithium carbonate was engaged in mild intermittent work for 4 hours under hot/dry climatic conditions (Ta = 37 degrees C, rh = 15%). The subject lost consciousness, was hyperthermic and suffered from disseminated intravascular coagulation. A year later residual cerebellar symptoms were still evident and severe atrophy of the cerebellar tissue was demonstrated in a CT scan. It is suggested that drug-induced heat intolerance was the predisposing factor that reduced the patient ability to sustain exercise-heat stress, and under the favorable environmental circumstances led to excessive heat accumulation which ultimately caused heat stroke. This is the first description, to our knowledge, of heat intolerance of a patient treated by a combination of fluoxetine and lithium carbonate. PMID: 9100934 [PubMed - indexed for MEDLINE] Hosp Community Psychiatry 1982 Jun;33(6):474-6 Related Articles, Books, LinkOut The prevention and treatment of heatstroke in psychiatric patients. Bark NM. Heatstroke is a serious medical condition that affects people in all climates. There is some preliminary evidence that psychiatric patients and those on psychotropic drugs are particularly susceptible. The author discusses the signs and symptoms of heatstroke, the factors that lead to it, and the appropriate preventive and treatment measures that should be taken. He concludes that heatstroke in psychiatric patients is totally preventable, but that should heatstroke occur, quick recognition and treatment can prevent death. PMID: 6124500 [PubMed - indexed for MEDLINE] Am J Psychiatry 2000 Aug;157(8):1327-9 Related Articles, Books, LinkOut Heat intolerance in patients with chronic schizophrenia maintained with antipsychotic drugs. Hermesh H, Shiloh R, Epstein Y, Manaim H, Weizman A, Munitz H. Geha Psychiatric Hospital, Petah Tiqva, Israel. hermesh@... OBJECTIVE: Schizophrenia may be associated with hyperthermic syndromes such as febrile catatonia, neuroleptic malignant syndrome, and heatstroke. The authors hypothesized that an exercise-heat tolerance test would disclose abnormal thermoregulation in schizophrenic patients. METHOD: Seven male schizophrenic outpatients in remission maintained on depot antipsychotic treatment and eight healthy comparison subjects completed a heat tolerance test that consisted of two 50-minute bouts of walking a motor-driven treadmill at 40xC (relative humidity=40%). RESULTS: A significantly higher rise in rectal and skin temperatures was observed in the patient group. No differences in heart rate, blood pressure, or perspiration were detected. CONCLUSIONS: Schizophrenic patients maintained on antipsychotic drugs exhibit impaired heat tolerance. Possible explanations are a reduced ability to convey heat from the body's core to the periphery with or without excessive heat production. The hyperthermic response to the heat tolerance test may reflect a dysfunction associated with schizophrenia, a neuroleptic-induced side effect, or both. PMID: 10910799 [PubMed - indexed for MEDLINE] Lancet 1996 Apr 13;347(9007):1016 Related Articles, Books, LinkOut A depressed workman with heatstroke. Albukrek D, Moran DS, Epstein Y. IDF Medical Corps, Institute of Military Physiology; and Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. PMID: 8606565 [PubMed - indexed for MEDLINE] Prog Brain Res 1998;115:193-204 Related Articles, Books, LinkOut The effects of drugs on thermoregulation during exposure to hot environments. Lomax P, Schonbaum E. School of Medicine, University of California, Los Angeles 90024, USA. Publication Types: Review Review, Tutorial PMID: 9632937 [PubMed - indexed for MEDLINE] Ned Tijdschr Geneeskd 1995 Jul 8;139(27):1391-3 Related Articles, Books, LinkOut Comment in: • Ned Tijdschr Geneeskd. 1996 Feb 17;140(7):388. [Psychiatric drugs as risk factor in fatal heat stroke] [Article in Dutch] Fijnheer R, van de Ven PJ, Erkelens DW. Afd. Interne Geneeskunde, Academisch Ziekenhuis, Utrecht. Two men aged 33 and 31 years suffered a fatal heat stroke on a warm summer day. One of them used pimozide and clomipramine, the other zuclopenthixol, dexetimide, droperidol, promethazine and propranolol as psychiatric medication. Both of them had a body temperature > 42.3 degrees C, without perspiring. At first only a comatose situation with practically normal laboratory values existed; this was rapidly followed by massive liver damage, disseminated intravascular coagulation, anaemia, thrombopenia and acute renal failure. In spite of adequate and rapid treatment these complications were fatal. Both patients used medication with an antidopaminergic and anticholinergic (side) effect. The set point of the temperature regulation centre can be elevated by the antidopaminergic activity of antipsychotics. Use of anticholinergic medication can disturb the thermoregulation via inhibition of the parasympathicomimetically mediated sweat secretion. It is recommended to point out the danger of unusually high outdoor temperatures to patients using this medication. PMID: 7617062 [PubMed - indexed for MEDLINE] : Ned Tijdschr Geneeskd 1995 Aug 26;139(34):1759-60 Related Articles, Books, LinkOut Comment on: Ned Tijdschr Geneeskd. 1995 Jul 8;39(27):1391-3 [Psychiatric medication as risk factor for fatal heat collapse] [Article in Dutch] Conemans JM. Publication Types: Comment Letter PMID: 7566248 [PubMed - indexed for MEDLINE] Chest 1981 Aug;80(2):244-5 Related Articles, Books, LinkOut Heat stroke related to psychotropic medications and prior history of heat stroke. Caldroney RD. Publication Types: Letter PMID: 7249779 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1983 Feb;46(2):183-5 Related Articles, Books, LinkOut Cerebellar syndrome following neuroleptic induced heat stroke. Lefkowitz D, Ford CS, Rich C, Biller J, McHenry LC Jr. We report a patient in whom extreme hyperthermia, rhabdomyolysis, acute renal failure and a residual pancerebellar syndrome occurred while taking a combination of perphenazine and amitriptyline. We postulate that impaired thermoregulation due to psychotropic drugs was responsible for the development of heat stroke and that the cerebellar syndrome resulted directly from the elevated temperature. PMID: 6842224 [PubMed - indexed for MEDLINE] Minn Med 1977 Feb;60(2):103-6 Related Articles, Books, LinkOut Heat stroke associated with medications having anticholinergic effects. BE, Manoguerra AS, Lilja GP, Long RS, Ruiz E. PMID: 840206 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1987 Jul;50(7):937-8 Related Articles, Books, LinkOut Heat stress and neuroleptic drugs. Tacke U, Venalainen E. Publication Types: Letter PMID: 2887638 [PubMed - indexed for MEDLINE] J Clin Psychiatry 1982 Sep;43(9):377-80 Related Articles, Books, LinkOut Heatstroke in psychiatric patients: two cases and a review. Bark NM. Two fatal cases of heatstroke in psychiatric patients are described. A literature search revealed published reports of heatstroke involving 51 psychiatric patients, 22 of whom died. The mean age of these patients was 44 years; the majority has schizophrenia. Almost all were male and were taking antipsychotic or other drugs with anticholinergic effects. The implications for prevention, recognition, and treatment are discussed. PMID: 6126476 [PubMed - indexed for MEDLINE] Ann Anesthesiol Fr 1979;20(8):709-16 Related Articles, Books, LinkOut [Heatstroke among psychiatric patients under neuroleptic therapy. Apropos of 2 fatal cases] [Article in French] Ducrot P, Jouan JC, Sala JP, Mathon J. Heat stroke is uncommon in temperate climates but may be favourised by drug treatment. A report of two cases of fatal hyperthermia occuring in patients treated with neuroleptic drugs and during a heat wave is followed by a discussion of the characteristics which may be used to differentiate heat stroke from the hyperthermia of malignant twenty cases. It indicated that high degree of severity of this type of heat stroke, in great part related to the high prevalence of massive inhalation. The action of neuroleptics is very probably central by an effect upon the thermostat and also by changes in behaviour. The role of associated anti-parkinsonian agents is discussed. A review of treatment emphasises its difficulties. Publication Types: Review PMID: 44988 [PubMed - indexed for MEDLINE] 1: Gen Hosp Psychiatry 1985 Oct;7(4):361-3 Related Articles, Books, LinkOut Heatstroke in a chronic schizophrenic patient treated with high-potency neuroleptics. Lazarus A. A fatal case of heatstroke occurred in a chronic schizophrenic patient treated with high-potency neuroleptics. The author differentiates heatstroke from other hyperthermic syndromes related to treatment with major tranquilizers and suggests that an awareness of factors that predispose psychiatric patients to the development of heatstroke may aid in its prevention. PMID: 2866145 [PubMed - indexed for MEDLINE] Pitt DC, Kriel RL, Wagner NC, Krach LE. Related Articles Kluver-Bucy syndrome following heat stroke in a 12-year-old girl. Pediatr Neurol. 1995 Jul;13(1):73-6. PMID: 7575855 [PubMed - indexed for MEDLINE] Pediatr Neurol 1987 May-Jun;3(3):162-5 Related Articles, Books, LinkOut Kluver-Bucy syndrome in children. Tonsgard JH, Harwicke N, Levine SC. Department of Pediatrics, University of Chicago, IL 60637. Kluver-Bucy syndrome is an uncommon syndrome of behavioral abnormalities following bilateral temporal lobe injury. Only four children have been reported previously with this syndrome. We report three additional pediatric patients who developed Kluver-Bucy syndrome following hypoxic insults. In two patients, features of the syndrome were transient. Problems in intermediate memory were present in each patient. Behavioral abnormalities did not respond to the medications administered. Our experience suggests that Kluver-Bucy syndrome may occur more commonly in children than was suspected previously, especially following hypoxia. PMID: 3508062 [PubMed - indexed for MEDLINE] J Neurosurg Sci 1997 Sep;41(3):269-72 Related Articles, Books, LinkOut The Kluver-Bucy syndrome. Goscinski I, Kwiatkowski S, Polak J, Orlowiejska M, Partyk A. Jagiellonian University, Medical Faculty, Department of Neurotraumatology, Krakow, Poland. Evolution of psychological disorders following head injury including memory disorders and other cognitive ones are common. The best known are psychiatric disturbances of various kind after lesions of frontal lobes. Cognitive, behavioural and emotional disorders are not usually seen in patients with bilateral temporal lesions. In our Department of Neurotraumatology we observed 4 patients with post-traumatic lesions localized bitemporally. They developed Kluver-Bucy syndrome--rarity in human pathology--with combination of three or more the following syndromes: increased oral activity, hypersexuality, hypermetamorphosis, memory disorders, placidity, loss of people recognition, bulimia. Several symptoms responded dramatically to carbamazepine. We conclude that it may be a useful agent in treatment of this unusual syndrome. PMID: 9444580 [PubMed - indexed for MEDLINE] Am Fam Physician 1998 Sep 1;58(3):749-56, 759 Related Articles, Books, LinkOut Heat-related illnesses. Barrow MW, KA. State University School of Medicine, Dayton, Ohio, USA. Heat-related illnesses cause 240 deaths annually. Although common in athletes, heat-related illnesses also affect the elderly, persons with predisposing medical conditions and those taking a variety of medications. Symptoms range from mild weakness, dizziness and fatigue in cases of heat edema, to syncope, exhaustion and multisystem complications, including coma and death, in cases of heat stroke. Milder heat-related symptoms can be treated with hydration, rest and removal from the hot environment. Heat stroke, a life-threatening problem, must be treated emergently. Prompt recognition is critical since rapid cooling is the cornerstone of treatment and must not be delayed. Fluid resuscitation with dextrose and normal or half-normal saline is also important. These therapies should be instituted while the patient is being stabilized. Heat illness may be prevented by recognizing which individuals are at risk, using appropriate hydration and paying attention to acclimatization and environmental conditions. Preventive care should include drinking plenty of fluids before, during and after activities, gradually increasing the time spent working in the heat and avoiding exertion during the hottest part of the day. Publication Types: Review Review, Tutorial PMID: 9750542 [PubMed - indexed for MEDLINE] http://abcnews.go.com/sections/living/Healthology/heatwave_dangers.html Heat Wave Dangers A. Finkel, MD, Massachusetts General Hospital Most often, heat-related illnesses are preventable conditions. However, they can have significant consequences, including death, if left untreated. The illnesses are traditionally divided into two main categories-heat exhaustion and heat stroke. These conditions can overlap in many ways and exist on a continuum of severity. As a patient's body temperature rises, heat exhaustion can rapidly progress to heat stroke. Heat Exhaustion and Heat Stroke Heat exhaustion develops when the body encounters excessively high temperatures that it is not used to managing. It occurs at body temperatures that are very high, but usually less than 40 degrees Celsius, or 104 degrees Fahrenheit. The symptoms of heat exhaustion are not very specific, but ultimately relate to a state of dehydration, which is the condition's primary characteristic. Symptoms may include weakness, headache, and nausea. Heat stroke is severe injury from high body temperatures that causes damage to many organs, particularly the central nervous system, which include the brain and spinal cord. In contrast to heat exhaustion, patients suffering from heat stroke will have temperatures that are usually greater 104 degrees. Heat stroke may be divided into two categories-exertional and classic. Exertional heat stroke Exertional heat stroke patients are usually people who are exercising in excessively warm conditions. Their bodies cannot manage the stress of the physical activity and the hot environment together. Classic heat stroke Classic heat stroke patients are often elderly or debilitated people who are in warm environments for too long. The elderly are especially vulnerable to the heat, as the body is less and less able to handle heat as it ages. Elderly people may also have pre-existing illnesses that make them more susceptible to heat stroke, or they make take medications that affect the body's ability to manage hot temperatures. Elderly people, who, for economic reasons, are not able to get out of the heat, are at great risk for heat stroke. Heat Transfer In order to understand heat-related illnesses you need to know something about the way the body normally gets rid of heat. There are four ways the body transfers heat: radiation, evaporation, conduction, and convection. Radiation Radiation occurs when the body turns heat into electromagnetic waves. In other words, waves of heat can escape from the body directly into the surrounding air. This is the primary way that human beings are able to lose heat from their bodies in very hot environments. Evaporation Evaporation is the transfer of heat that occurs during the transformation of liquid to gas. Evaporation of sweat (even of sweat you cannot feel, called insensiblelosses) is another significant method that the body uses to cool down. Convection and conduction Convection and conduction are secondary ways for the body to lose heat after radiation and evaporation. Convection is the passage of heat into the air and into the vapor that surrounds the body. It is different from evaporation in that the heat does not transform to the gas phase, as it does in evaporation. Conduction is the transfer of heat through physical contact. What Happens When it Gets Too Hot In hot environments, the body initiates several processes to lose heat. First, the anterior hypothalamus, the body's thermostat in the brain, signals the body to open up blood vessels near the skin's surface so that heat can be transferred outside by the methods listed above. This vessel dilation is possible because blood is shunted away from the body's core. The hypothalamus also mediates sweating and tells the body to respond to the heat by taking off clothes and seeking a cooler environment. When it becomes too hot, however, the body's ability to cool down becomes overwhelmed. Symptoms like fatigue, headache, muscle aches, confusion, and even coma can occur, depending on the severity of the condition. This overwhelming of the body's means of handling heat can be caused by a very warm environment or excessive exercising in the heat, as discussed before. Also, though, patients may get overheated because of certain illnesses like hyperthyroidism (high thyroid hormone level) or infections causing fever. Additionally, some medications can cause high body temperatures. A class of drugs called anticholinergics can decrease the body's ability to sweat and, therefore, to lose heat. Other drugs called sympathomimetics can decrease skin vessel dilation. There are other classes of drugs that may also interfere with body temperature regulation through various, sometimes complicated, mechanisms. Symptoms and Signs There are a variety of symptoms associated with heat-related illnesses. Heat exhaustion patients may have vague complaints of symptoms that come on slowly. These can include: • Headache • Weakness • Lightheadedness • Muscle aches • Muscle cramps • Agitation Heat stroke patients can have the same complaints as heat exhaustion patients, but they also suffer central nervous system problems, which can include: • Confusion hallucinations • Bizarre behavior • Seizure • Coma It was once thought that heat stroke patients did not sweat, but this inability to sweat is variable, and often strikes the patient at the latest stages of the condition. Heat stroke patients, because of the resulting multi-organ damage, may also complain of blood in the urine or stool, decline in the amount of urine produced and shortness of breath, among other problems. Other symptoms There are secondary categories of heat-related illnesses to watch out for: • Heat syncope occurs when a person overheats and then faints. • Heat cramps are muscle contractions associated with electrolyte or mineral abnormalities caused by the heat. • Heat edema is characterized by swelling in the arms and legs because of the heat. • Prickly heat is a heat rash that is red and very itchy. Treatment There is a lot that you can do for a person suffering from a heat-related illness. If you see someone who appears to be suffering from a heat-related illness, you should call for help immediately. In the most rare, severe cases, you should start cardiopulmonary resuscitation (CPR), if necessary. If the person is not a trauma patient (has not been in an accident, fight, or fall), you should move the individual from the hot environment to a cooler location. Next you can sprinkle lukewarm water on the skin and fan the patient; this will encourage evaporation. You can also apply ice packs to the neck, underarms, and groin. In the emergency room Once a patient has been taken to the emergency room, the cooling process will be continued. The doctor may use a cooling blanket and some other more aggressive methods, but in general, treatment is similar to the methods that should be initiated immediately, including fanning and ice packs. The doctor may order tests to assess organ damage. These tests can include electrolytes or minerals, blood-clotting tests, a urine analysis, creatine phosphokinase (a muscle enzyme quantification), and a head computed tomography (CT or cat) scan. Heat stroke patients are admitted to the intensive care unit. Heat exhaustion patients are admitted to a regular floor bed in the hospital. When patients are released from the hospital, they should have a place to go to avoid the heat, and they must be able to rehydrate themselves. If caretakers are aggressive with these cooling techniques before delivering the patient to the hospital, and the emergency department is able to treat any related organ damage, then there is a good possibility that the prognosis will be excellent. Prevention Heat-related illnesses are often preventable. When hot weather is expected, the elderly and debilitated must be ensured access to cool, air-conditioned shelter. People should be encouraged to wear light-colored, loose clothing and bathe in tepid water. Also, hydration is critical, and people in hot weather should increase their fluid intake substantially. To avoid exertional heat stroke, athletes should not exercise in extreme heat, and coaches should be aware of the symptoms of heat-related illnesses. Athletes also must stay well-hydrated. Summary Heat-related illnesses are a continuum of conditions but have traditionally been divided into heat exhaustion-characterized by dehydration-and heat stroke, in which organs, particularly the central nervous system, are damaged. Heat exhaustion patients may have vague complaints like weakness, nausea and headache, whereas heat stroke patients often have these symptoms plus confusion or hallucinations. Heat-related illnesses present a potentially severe-even fatal-set of conditions that can often be prevented if treated early and aggressively. Learning about the symptoms and preventive care can help you help someone else. Can You Handle the Heat? Copyright 2001 Healthology, Inc. All rights reserved. This material may not be published, broadcast, rewritten or redistributed _________________________________________________________________ Send and receive Hotmail on your mobile device: http://mobile.msn.com Quote Link to comment Share on other sites More sharing options...
Guest guest Posted July 1, 2002 Report Share Posted July 1, 2002 Dear Group, Anyone taking Prozac, or any other SSRI, and the weather is warm, must be very careful not to overheat. The body's ability to cool its core temperature is damaged. noticed that there is a HOT MED policy in place where those on Prozac and the like are restricted to air-conditioned rooms when the temp approaches 90 degrees. Here is the reason why: Ann N Y Acad Sci 1997 Mar 15;813:553-8 Related Articles, Books, LinkOut Heat intolerance induced by antidepressants. Epstein Y, Albukrek D, Kalmovitc B, Moran DS, Shapiro Y. Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. A case in which prescription medications induced heat intolerance which led to heat stroke is presented. A subject who suffered from depression and was treated with fluoxetine HCL (prozac) and lithium carbonate was engaged in mild intermittent work for 4 hours under hot/dry climatic conditions (Ta = 37 degrees C, rh = 15%). The subject lost consciousness, was hyperthermic and suffered from disseminated intravascular coagulation. A year later residual cerebellar symptoms were still evident and severe atrophy of the cerebellar tissue was demonstrated in a CT scan. It is suggested that drug-induced heat intolerance was the predisposing factor that reduced the patient ability to sustain exercise-heat stress, and under the favorable environmental circumstances led to excessive heat accumulation which ultimately caused heat stroke. This is the first description, to our knowledge, of heat intolerance of a patient treated by a combination of fluoxetine and lithium carbonate. PMID: 9100934 [PubMed - indexed for MEDLINE] Hosp Community Psychiatry 1982 Jun;33(6):474-6 Related Articles, Books, LinkOut The prevention and treatment of heatstroke in psychiatric patients. Bark NM. Heatstroke is a serious medical condition that affects people in all climates. There is some preliminary evidence that psychiatric patients and those on psychotropic drugs are particularly susceptible. The author discusses the signs and symptoms of heatstroke, the factors that lead to it, and the appropriate preventive and treatment measures that should be taken. He concludes that heatstroke in psychiatric patients is totally preventable, but that should heatstroke occur, quick recognition and treatment can prevent death. PMID: 6124500 [PubMed - indexed for MEDLINE] Am J Psychiatry 2000 Aug;157(8):1327-9 Related Articles, Books, LinkOut Heat intolerance in patients with chronic schizophrenia maintained with antipsychotic drugs. Hermesh H, Shiloh R, Epstein Y, Manaim H, Weizman A, Munitz H. Geha Psychiatric Hospital, Petah Tiqva, Israel. hermesh@... OBJECTIVE: Schizophrenia may be associated with hyperthermic syndromes such as febrile catatonia, neuroleptic malignant syndrome, and heatstroke. The authors hypothesized that an exercise-heat tolerance test would disclose abnormal thermoregulation in schizophrenic patients. METHOD: Seven male schizophrenic outpatients in remission maintained on depot antipsychotic treatment and eight healthy comparison subjects completed a heat tolerance test that consisted of two 50-minute bouts of walking a motor-driven treadmill at 40xC (relative humidity=40%). RESULTS: A significantly higher rise in rectal and skin temperatures was observed in the patient group. No differences in heart rate, blood pressure, or perspiration were detected. CONCLUSIONS: Schizophrenic patients maintained on antipsychotic drugs exhibit impaired heat tolerance. Possible explanations are a reduced ability to convey heat from the body's core to the periphery with or without excessive heat production. The hyperthermic response to the heat tolerance test may reflect a dysfunction associated with schizophrenia, a neuroleptic-induced side effect, or both. PMID: 10910799 [PubMed - indexed for MEDLINE] Lancet 1996 Apr 13;347(9007):1016 Related Articles, Books, LinkOut A depressed workman with heatstroke. Albukrek D, Moran DS, Epstein Y. IDF Medical Corps, Institute of Military Physiology; and Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. PMID: 8606565 [PubMed - indexed for MEDLINE] Prog Brain Res 1998;115:193-204 Related Articles, Books, LinkOut The effects of drugs on thermoregulation during exposure to hot environments. Lomax P, Schonbaum E. School of Medicine, University of California, Los Angeles 90024, USA. Publication Types: Review Review, Tutorial PMID: 9632937 [PubMed - indexed for MEDLINE] Ned Tijdschr Geneeskd 1995 Jul 8;139(27):1391-3 Related Articles, Books, LinkOut Comment in: • Ned Tijdschr Geneeskd. 1996 Feb 17;140(7):388. [Psychiatric drugs as risk factor in fatal heat stroke] [Article in Dutch] Fijnheer R, van de Ven PJ, Erkelens DW. Afd. Interne Geneeskunde, Academisch Ziekenhuis, Utrecht. Two men aged 33 and 31 years suffered a fatal heat stroke on a warm summer day. One of them used pimozide and clomipramine, the other zuclopenthixol, dexetimide, droperidol, promethazine and propranolol as psychiatric medication. Both of them had a body temperature > 42.3 degrees C, without perspiring. At first only a comatose situation with practically normal laboratory values existed; this was rapidly followed by massive liver damage, disseminated intravascular coagulation, anaemia, thrombopenia and acute renal failure. In spite of adequate and rapid treatment these complications were fatal. Both patients used medication with an antidopaminergic and anticholinergic (side) effect. The set point of the temperature regulation centre can be elevated by the antidopaminergic activity of antipsychotics. Use of anticholinergic medication can disturb the thermoregulation via inhibition of the parasympathicomimetically mediated sweat secretion. It is recommended to point out the danger of unusually high outdoor temperatures to patients using this medication. PMID: 7617062 [PubMed - indexed for MEDLINE] : Ned Tijdschr Geneeskd 1995 Aug 26;139(34):1759-60 Related Articles, Books, LinkOut Comment on: Ned Tijdschr Geneeskd. 1995 Jul 8;39(27):1391-3 [Psychiatric medication as risk factor for fatal heat collapse] [Article in Dutch] Conemans JM. Publication Types: Comment Letter PMID: 7566248 [PubMed - indexed for MEDLINE] Chest 1981 Aug;80(2):244-5 Related Articles, Books, LinkOut Heat stroke related to psychotropic medications and prior history of heat stroke. Caldroney RD. Publication Types: Letter PMID: 7249779 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1983 Feb;46(2):183-5 Related Articles, Books, LinkOut Cerebellar syndrome following neuroleptic induced heat stroke. Lefkowitz D, Ford CS, Rich C, Biller J, McHenry LC Jr. We report a patient in whom extreme hyperthermia, rhabdomyolysis, acute renal failure and a residual pancerebellar syndrome occurred while taking a combination of perphenazine and amitriptyline. We postulate that impaired thermoregulation due to psychotropic drugs was responsible for the development of heat stroke and that the cerebellar syndrome resulted directly from the elevated temperature. PMID: 6842224 [PubMed - indexed for MEDLINE] Minn Med 1977 Feb;60(2):103-6 Related Articles, Books, LinkOut Heat stroke associated with medications having anticholinergic effects. BE, Manoguerra AS, Lilja GP, Long RS, Ruiz E. PMID: 840206 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1987 Jul;50(7):937-8 Related Articles, Books, LinkOut Heat stress and neuroleptic drugs. Tacke U, Venalainen E. Publication Types: Letter PMID: 2887638 [PubMed - indexed for MEDLINE] J Clin Psychiatry 1982 Sep;43(9):377-80 Related Articles, Books, LinkOut Heatstroke in psychiatric patients: two cases and a review. Bark NM. Two fatal cases of heatstroke in psychiatric patients are described. A literature search revealed published reports of heatstroke involving 51 psychiatric patients, 22 of whom died. The mean age of these patients was 44 years; the majority has schizophrenia. Almost all were male and were taking antipsychotic or other drugs with anticholinergic effects. The implications for prevention, recognition, and treatment are discussed. PMID: 6126476 [PubMed - indexed for MEDLINE] Ann Anesthesiol Fr 1979;20(8):709-16 Related Articles, Books, LinkOut [Heatstroke among psychiatric patients under neuroleptic therapy. Apropos of 2 fatal cases] [Article in French] Ducrot P, Jouan JC, Sala JP, Mathon J. Heat stroke is uncommon in temperate climates but may be favourised by drug treatment. A report of two cases of fatal hyperthermia occuring in patients treated with neuroleptic drugs and during a heat wave is followed by a discussion of the characteristics which may be used to differentiate heat stroke from the hyperthermia of malignant twenty cases. It indicated that high degree of severity of this type of heat stroke, in great part related to the high prevalence of massive inhalation. The action of neuroleptics is very probably central by an effect upon the thermostat and also by changes in behaviour. The role of associated anti-parkinsonian agents is discussed. A review of treatment emphasises its difficulties. Publication Types: Review PMID: 44988 [PubMed - indexed for MEDLINE] 1: Gen Hosp Psychiatry 1985 Oct;7(4):361-3 Related Articles, Books, LinkOut Heatstroke in a chronic schizophrenic patient treated with high-potency neuroleptics. Lazarus A. A fatal case of heatstroke occurred in a chronic schizophrenic patient treated with high-potency neuroleptics. The author differentiates heatstroke from other hyperthermic syndromes related to treatment with major tranquilizers and suggests that an awareness of factors that predispose psychiatric patients to the development of heatstroke may aid in its prevention. PMID: 2866145 [PubMed - indexed for MEDLINE] Pitt DC, Kriel RL, Wagner NC, Krach LE. Related Articles Kluver-Bucy syndrome following heat stroke in a 12-year-old girl. Pediatr Neurol. 1995 Jul;13(1):73-6. PMID: 7575855 [PubMed - indexed for MEDLINE] Pediatr Neurol 1987 May-Jun;3(3):162-5 Related Articles, Books, LinkOut Kluver-Bucy syndrome in children. Tonsgard JH, Harwicke N, Levine SC. Department of Pediatrics, University of Chicago, IL 60637. Kluver-Bucy syndrome is an uncommon syndrome of behavioral abnormalities following bilateral temporal lobe injury. Only four children have been reported previously with this syndrome. We report three additional pediatric patients who developed Kluver-Bucy syndrome following hypoxic insults. In two patients, features of the syndrome were transient. Problems in intermediate memory were present in each patient. Behavioral abnormalities did not respond to the medications administered. Our experience suggests that Kluver-Bucy syndrome may occur more commonly in children than was suspected previously, especially following hypoxia. PMID: 3508062 [PubMed - indexed for MEDLINE] J Neurosurg Sci 1997 Sep;41(3):269-72 Related Articles, Books, LinkOut The Kluver-Bucy syndrome. Goscinski I, Kwiatkowski S, Polak J, Orlowiejska M, Partyk A. Jagiellonian University, Medical Faculty, Department of Neurotraumatology, Krakow, Poland. Evolution of psychological disorders following head injury including memory disorders and other cognitive ones are common. The best known are psychiatric disturbances of various kind after lesions of frontal lobes. Cognitive, behavioural and emotional disorders are not usually seen in patients with bilateral temporal lesions. In our Department of Neurotraumatology we observed 4 patients with post-traumatic lesions localized bitemporally. They developed Kluver-Bucy syndrome--rarity in human pathology--with combination of three or more the following syndromes: increased oral activity, hypersexuality, hypermetamorphosis, memory disorders, placidity, loss of people recognition, bulimia. Several symptoms responded dramatically to carbamazepine. We conclude that it may be a useful agent in treatment of this unusual syndrome. PMID: 9444580 [PubMed - indexed for MEDLINE] Am Fam Physician 1998 Sep 1;58(3):749-56, 759 Related Articles, Books, LinkOut Heat-related illnesses. Barrow MW, KA. State University School of Medicine, Dayton, Ohio, USA. Heat-related illnesses cause 240 deaths annually. Although common in athletes, heat-related illnesses also affect the elderly, persons with predisposing medical conditions and those taking a variety of medications. Symptoms range from mild weakness, dizziness and fatigue in cases of heat edema, to syncope, exhaustion and multisystem complications, including coma and death, in cases of heat stroke. Milder heat-related symptoms can be treated with hydration, rest and removal from the hot environment. Heat stroke, a life-threatening problem, must be treated emergently. Prompt recognition is critical since rapid cooling is the cornerstone of treatment and must not be delayed. Fluid resuscitation with dextrose and normal or half-normal saline is also important. These therapies should be instituted while the patient is being stabilized. Heat illness may be prevented by recognizing which individuals are at risk, using appropriate hydration and paying attention to acclimatization and environmental conditions. Preventive care should include drinking plenty of fluids before, during and after activities, gradually increasing the time spent working in the heat and avoiding exertion during the hottest part of the day. Publication Types: Review Review, Tutorial PMID: 9750542 [PubMed - indexed for MEDLINE] http://abcnews.go.com/sections/living/Healthology/heatwave_dangers.html Heat Wave Dangers A. Finkel, MD, Massachusetts General Hospital Most often, heat-related illnesses are preventable conditions. However, they can have significant consequences, including death, if left untreated. The illnesses are traditionally divided into two main categories-heat exhaustion and heat stroke. These conditions can overlap in many ways and exist on a continuum of severity. As a patient's body temperature rises, heat exhaustion can rapidly progress to heat stroke. Heat Exhaustion and Heat Stroke Heat exhaustion develops when the body encounters excessively high temperatures that it is not used to managing. It occurs at body temperatures that are very high, but usually less than 40 degrees Celsius, or 104 degrees Fahrenheit. The symptoms of heat exhaustion are not very specific, but ultimately relate to a state of dehydration, which is the condition's primary characteristic. Symptoms may include weakness, headache, and nausea. Heat stroke is severe injury from high body temperatures that causes damage to many organs, particularly the central nervous system, which include the brain and spinal cord. In contrast to heat exhaustion, patients suffering from heat stroke will have temperatures that are usually greater 104 degrees. Heat stroke may be divided into two categories-exertional and classic. Exertional heat stroke Exertional heat stroke patients are usually people who are exercising in excessively warm conditions. Their bodies cannot manage the stress of the physical activity and the hot environment together. Classic heat stroke Classic heat stroke patients are often elderly or debilitated people who are in warm environments for too long. The elderly are especially vulnerable to the heat, as the body is less and less able to handle heat as it ages. Elderly people may also have pre-existing illnesses that make them more susceptible to heat stroke, or they make take medications that affect the body's ability to manage hot temperatures. Elderly people, who, for economic reasons, are not able to get out of the heat, are at great risk for heat stroke. Heat Transfer In order to understand heat-related illnesses you need to know something about the way the body normally gets rid of heat. There are four ways the body transfers heat: radiation, evaporation, conduction, and convection. Radiation Radiation occurs when the body turns heat into electromagnetic waves. In other words, waves of heat can escape from the body directly into the surrounding air. This is the primary way that human beings are able to lose heat from their bodies in very hot environments. Evaporation Evaporation is the transfer of heat that occurs during the transformation of liquid to gas. Evaporation of sweat (even of sweat you cannot feel, called insensiblelosses) is another significant method that the body uses to cool down. Convection and conduction Convection and conduction are secondary ways for the body to lose heat after radiation and evaporation. Convection is the passage of heat into the air and into the vapor that surrounds the body. It is different from evaporation in that the heat does not transform to the gas phase, as it does in evaporation. Conduction is the transfer of heat through physical contact. What Happens When it Gets Too Hot In hot environments, the body initiates several processes to lose heat. First, the anterior hypothalamus, the body's thermostat in the brain, signals the body to open up blood vessels near the skin's surface so that heat can be transferred outside by the methods listed above. This vessel dilation is possible because blood is shunted away from the body's core. The hypothalamus also mediates sweating and tells the body to respond to the heat by taking off clothes and seeking a cooler environment. When it becomes too hot, however, the body's ability to cool down becomes overwhelmed. Symptoms like fatigue, headache, muscle aches, confusion, and even coma can occur, depending on the severity of the condition. This overwhelming of the body's means of handling heat can be caused by a very warm environment or excessive exercising in the heat, as discussed before. Also, though, patients may get overheated because of certain illnesses like hyperthyroidism (high thyroid hormone level) or infections causing fever. Additionally, some medications can cause high body temperatures. A class of drugs called anticholinergics can decrease the body's ability to sweat and, therefore, to lose heat. Other drugs called sympathomimetics can decrease skin vessel dilation. There are other classes of drugs that may also interfere with body temperature regulation through various, sometimes complicated, mechanisms. Symptoms and Signs There are a variety of symptoms associated with heat-related illnesses. Heat exhaustion patients may have vague complaints of symptoms that come on slowly. These can include: • Headache • Weakness • Lightheadedness • Muscle aches • Muscle cramps • Agitation Heat stroke patients can have the same complaints as heat exhaustion patients, but they also suffer central nervous system problems, which can include: • Confusion hallucinations • Bizarre behavior • Seizure • Coma It was once thought that heat stroke patients did not sweat, but this inability to sweat is variable, and often strikes the patient at the latest stages of the condition. Heat stroke patients, because of the resulting multi-organ damage, may also complain of blood in the urine or stool, decline in the amount of urine produced and shortness of breath, among other problems. Other symptoms There are secondary categories of heat-related illnesses to watch out for: • Heat syncope occurs when a person overheats and then faints. • Heat cramps are muscle contractions associated with electrolyte or mineral abnormalities caused by the heat. • Heat edema is characterized by swelling in the arms and legs because of the heat. • Prickly heat is a heat rash that is red and very itchy. Treatment There is a lot that you can do for a person suffering from a heat-related illness. If you see someone who appears to be suffering from a heat-related illness, you should call for help immediately. In the most rare, severe cases, you should start cardiopulmonary resuscitation (CPR), if necessary. If the person is not a trauma patient (has not been in an accident, fight, or fall), you should move the individual from the hot environment to a cooler location. Next you can sprinkle lukewarm water on the skin and fan the patient; this will encourage evaporation. You can also apply ice packs to the neck, underarms, and groin. In the emergency room Once a patient has been taken to the emergency room, the cooling process will be continued. The doctor may use a cooling blanket and some other more aggressive methods, but in general, treatment is similar to the methods that should be initiated immediately, including fanning and ice packs. The doctor may order tests to assess organ damage. These tests can include electrolytes or minerals, blood-clotting tests, a urine analysis, creatine phosphokinase (a muscle enzyme quantification), and a head computed tomography (CT or cat) scan. Heat stroke patients are admitted to the intensive care unit. Heat exhaustion patients are admitted to a regular floor bed in the hospital. When patients are released from the hospital, they should have a place to go to avoid the heat, and they must be able to rehydrate themselves. If caretakers are aggressive with these cooling techniques before delivering the patient to the hospital, and the emergency department is able to treat any related organ damage, then there is a good possibility that the prognosis will be excellent. Prevention Heat-related illnesses are often preventable. When hot weather is expected, the elderly and debilitated must be ensured access to cool, air-conditioned shelter. People should be encouraged to wear light-colored, loose clothing and bathe in tepid water. Also, hydration is critical, and people in hot weather should increase their fluid intake substantially. To avoid exertional heat stroke, athletes should not exercise in extreme heat, and coaches should be aware of the symptoms of heat-related illnesses. Athletes also must stay well-hydrated. Summary Heat-related illnesses are a continuum of conditions but have traditionally been divided into heat exhaustion-characterized by dehydration-and heat stroke, in which organs, particularly the central nervous system, are damaged. Heat exhaustion patients may have vague complaints like weakness, nausea and headache, whereas heat stroke patients often have these symptoms plus confusion or hallucinations. Heat-related illnesses present a potentially severe-even fatal-set of conditions that can often be prevented if treated early and aggressively. Learning about the symptoms and preventive care can help you help someone else. Can You Handle the Heat? Copyright 2001 Healthology, Inc. All rights reserved. This material may not be published, broadcast, rewritten or redistributed http://www.merck.com/pubs/mmanual/section20/chapter279/279b.htm Heatstroke (Sunstroke; Thermic Fever; Siriasis) Inadequacy or failure of heat loss mechanisms resulting in dangerous hyperpyrexia. Symptoms and Signs An abrupt onset is sometimes preceded by headache, vertigo, and fatigue. Sweating is usually decreased, and the skin is hot, flushed, and usually dry. The pulse rate increases rapidly and may reach 160 to 180 beats/min; respirations usually increase, but BP is seldom affected. Disorientation may briefly precede unconsciousness or convulsions. The temperature climbs rapidly to 40 to 41° C (104 to 106° F), causing a feeling of burning up. Circulatory collapse may precede death; after hours of extreme hyperpyrexia, survivors are likely to have permanent brain damage. Diagnosis and Prognosis Sudden development of hot, dry, flushed skin with a body temperature > 40° C (> 104° F), a rapid pulse, and confusion or unconsciousness in a person exposed to a hot environment are usually enough to distinguish heatstroke from food, chemical, or drug poisoning. An acute infection (eg, septicemia, meningitis) and toxic shock must be excluded. Drugs (see above) that may have precipitated the episode should be considered. 1998-2002 On-line Medical Dictionary http://cancerweb.ncl.ac.uk/cgi-bin/omd?query=disseminate & action=Search+OMD Article 1. Heat Intolerance Induced by Antidepressants Disseminate To scatter or distribute over a considerable area. (18 Nov 1997) intravascular Within a vessel or vessels. Origin: L. Vasculum = vessel (18 Nov 1997) coagulation 1. <haematology> The process of clot formation. 2. <chemistry> The solidification of a sol into a gelatinous mass, an alteration of a disperse phase or of a dissolved solid which causes the separation of the system into a liquid phase and an insoluble mass called the clot or curd. Coagulation is usually irreversible. 3. <surgery> The disruption of tissue by physical means to form an amorphous residuum, as in electrocoagulation and photocoagulation. Origin: L. Coagulatio (18 Nov 1997) Article 3. Heat Intolerance in Patients… Maintained with Antipsychotic Drugs “Patients maintained on antipsychotic drugs exhibit impaired heat tolerance.” febrile <symptom> Pertaining to or characterised by fever. Origin: L. Febrilis (18 Nov 1997) catatonia <neurology, psychiatry> A syndrome of psychomotor disturbances seen in schizophrenic disorders characterised by periods of either muscular rigidity, excitement or stupor. (16 Mar 1998) neuroleptic <pharmacology> A term coined to refer to the effects on cognition and behaviour of antipsychotic drugs, which produce a state of apathy, lack of initiative and limited range of emotion and in psychotic patients cause a reduction in confusion and agitation and normalisation of psychomotor activity. Origin: Gr. Lepsis = a taking hold (18 Nov 1997) malignant <oncology> Tending to become progressively worse and to result in death. Having the properties of anaplasia, invasion and metastasis, said of tumours. Origin: L. Malignans = acting maliciously (18 Nov 1997) heatstroke A severe and often fatal illness produced by exposure to excessively high temperatures, especially when accompanied by marked exertion. It can manifest by elevated body temperature, lack of sweating, hot dry skin, and neurologic symptoms; unconsciousness, paralysis, headache, vertigo, confusion. In severe cases very high fever, vascular collapse, and coma develop. Synonym: heat apoplexy, heat hyperpyrexia, malignant hyperpyrexia, thermic fever. (05 Mar 2000) vertigo <neurology, symptom> An illusion of movement, a sensation as if the external world were revolving around the patient (objective vertigo) or as if he himself were revolving in space (subjective vertigo). The term is sometimes erroneously used to mean any form of dizziness. Origin: L. Vertigo (18 Nov 1997) heat apoplexy -->heatstroke A severe and often fatal illness produced by exposure to excessively high temperatures, especially when accompanied by marked exertion. It can manifest by elevated body temperature, lack of sweating, hot dry skin, and neurologic symptoms; unconsciousness, paralysis, headache, vertigo, confusion. In severe cases very high fever, vascular collapse, and coma develop. Synonym: heat apoplexy, heat hyperpyrexia, malignant hyperpyrexia, thermic fever. (05 Mar 2000 apoplexy <clinical sign, neurology> Haemorrhage into the brain. A stroke. It is usually associated with loss of consciousness and paralysis of various parts of the body. (27 Sep 1997) hyperpyrexia <clinical sign> Exceptionally high fever either in comparison of the fever usually accompanying a particular disease or absolutely (as in heatstroke). (18 Nov 1997) thermic fever -->heatstroke A severe and often fatal illness produced by exposure to excessively high temperatures, especially when accompanied by marked exertion. It can manifest by elevated body temperature, lack of sweating, hot dry skin, and neurologic symptoms; unconsciousness, paralysis, headache, vertigo, confusion. In severe cases very high fever, vascular collapse, and coma develop. Synonym: heat apoplexy, heat hyperpyrexia, malignant hyperpyrexia, thermic fever. (05 Mar 2000) Article 6. Psychiatric Drugs as Risk Factor in Fatal Heat Stroke anaemia <haematology> Too few red blood cells in the bloodstream, resulting in insufficient oxygen to tissues and organs. Origin: Gr. Haima = blood (16 Dec 1997) thrombopenia -->thrombocytopenia <haematology> A decrease in the number of platelets in the blood, resulting in the potential for increased bleeding and decreased ability for clotting. Origin: Gr. Penia = poverty (18 Nov 1997) renal failure Chronic renal failure represents a slow decline in kidney function over time. Chronic renal failure may be caused by a number of disorders which include long-standing hypertension, diabetes, congestive heart failure, lupus or sickle cell anaemia. If renal function declines to a low enough level (end-stage renal disease) kidney dialysis may be necessary. A sudden decline in renal function may be triggered by a number of acute disease processes. Examples include sepsis (infection), shock, trauma, kidney stones, kidney infection, drug toxicity (aspirin or lithium), poisons or toxins (drug abuse) or after injection with an iodinated contrast dye (adverse effect). Both forms of renal failure result in a life-threatening metabolic derangement. (27 Sep 1997) “The set point of the temperature regulation centre can be elevated by the antidopaminergic activity of antipsychotics” antidopaminergic Preventing or counteracting (the effects of) dopamine. (18 Nov 1997) anticholinergenic <pharmacology> Refers to an agent that inhibits parasympathetic neural activity by blocking the neurotransmitter acetylcholine. Origin: Gr. Gennan = to produce (09 Oct 1997) parasympathetic Pertaining to a division of the autonomic nervous system. See: autonomic nervous system. (05 Mar 2000) acetylcholine <chemical, neurology, physiology> A chemical found in vertebrate neurons that carries information across the synaptic cleft, the space between two nerve cells. (06 May 1997) “It is recommended to point out the danger of unusually high outdoor temperatures to patients using this medication.” Article 9. Cerebellar Syndrome Following Neuroleptic Induced Heat Stroke cerebellar syndrome <syndrome> The signs and symptoms of cerebellar deficiency: dysmetria, dysarthria, asynergia, nystagmus, ataxia, staggering gait, and adiadochokinesia. (05 Mar 2000) dysmetria An aspect of ataxia, in which the ability to control the distance, power, and speed of an act is impaired. Usually used to describe abnormalities of movement caused by cerebellar disorders. See: hypermetria, hypometria. Origin: dys-+ G. Metron, measure (05 Mar 2000) hypermetria Ataxia characterised by overreaching a desired object or goal; usually seen with cerebellar disorders. Compare: hypometria. Origin: hyper-+ G. Metron, measure (05 Mar 2000) hypometria Ataxia characterised by underreaching an object or goal; seen with cerebellar disease. Compare: hypermetria. Origin: hypo-+ G. Metron, measure (05 Mar 2000) dysarthria <clinical sign, neurology> Imperfect articulation of speech due to disturbances of muscular control which result from damage to the central or peripheral nervous system. Origin: Gr. Arthroun = to utter distinctly (18 Nov 1997) asynergia Synonym: asynergy. Origin: G. A-priv. + syn, with, + ergon, work (05 Mar 2000) asynergy Lack of coordination among various muscle groups during the performance of complex movements, resulting in loss of skill and speed. When severe, results in decomposition of movement, wherein complex motor acts are performed in a series of isolated movements; caused by cerebellar disorders. Synonym: asynergia. (05 Mar 2000) nystagmus <neurology> An involuntary, rapid, rhythmic movement of the eyeball, which may be horizontal, vertical, rotatory or mixed, i.e., of two varieties. Origin: Gr. Nystagmos = drowsiness, from nystazein = to nod (18 Nov 1997) ataxia <neurology> Failure of muscular coordination, irregularity of muscular action. Origin: Gr. Taxis = order (16 Dec 1997) adiadochocinesis -->adiadochokinesis Inability to perform rapid alternating movements. One of the clinical manifestations of cerebellar dysfunction. See: dysdiadochokinesia. Compare: diadochokinesia. Synonym: adiadochocinesia, adiadochocinesis, dysdiadochokinesis. Origin: G. A-priv. + diadochos, successive, + kinesis, movement (05 Mar 2000) rhabdomyolysis <pathology> The destruction of skeletal muscle cells. Often the result of electrical injury, alcoholism, injury (or laying in one position for an extended period of time), drug side effects or toxins. (27 Sep 1997) Results for: pancerebellar 1 results found, sorted by relevance 1-1 THE MERCK MANUAL, Sec. 14, Ch. 179, Disorders Of Movement Disorders of the cerebellum and its inflow or outflow pathways produce deficits in the rate, range, and force of movement. ... size 26.0K Cerebellar And Spinocerebellar Disorders Disorders of the cerebellum and its inflow or outflow pathways produce deficits in the rate, range, and force of movement. Anatomically, the cerebellum has three subdivisions. The archicerebellum (vestibulocerebellum) comprises the flocculonodular lobe, helps maintain equilibrium and coordinate eye-head-neck movements, and is closely interconnected with the vestibular nuclei. The midline vermis (paleocerebellum) helps coordinate movement of the trunk and legs. Vermis lesions result in abnormalities of stance and gait. The lateral hemispheres, which make up the neocerebellum, control ballistic and finely coordinated limb movements, predominantly of the arms. Signs of cerebellar disease are listed in Table 179-3. STRUCTURAL LESIONS OF THE CEREBELLUM Articles 15 – 17. Kulver-Bucy Syndrome Following Heat Stroke Results for: Kluver-Bucy syndrome 621 results found, top 500 sorted by relevance 1-10 THE MERCK MANUAL, Sec. 14, Ch. 171, Delirium And Dementia lists many of the known causes of dementia. Dementia may occur at any age and can affect young people as the result of injury or hypoxia ... size 55.1K Dementia A chronic deterioration of intellectual function and other cognitive skills severe enough to interfere with the ability to perform activities of daily living. Complications Behavioral complications include hostility, agitation, wandering, and uncooperativeness. Psychiatric complications include depression, anxiety, and paranoid reactions. True psychosis (paranoia, delusions, and hallucinations) probably occurs in about 10% of patients with Alzheimer's disease. In addition, perhaps 80% of family members or caregivers develop depression over time. Metabolic problems (eg, dehydration, infection, drug toxicity) can worsen cognitive impairment and make patient management more difficult. Other complications include falls, incontinence, and confusion at dusk (sundowning). The drugs commonly used to treat Alzheimer's disease (especially antipsychotics for behavior disorders) can cause a parkinsonian movement disorder and orthostatic hypotension. Tricyclic drugs with anticholinergic side effects can cause constipation, urinary retention, glaucoma, and seizures. Nonprescription antihistamines can lead to worsened confusion. These complications put the patient at risk of premature institutionalization and should be avoided or quickly treated, because many can be controlled or reversed. Many drugs adversely affect the CNS, increasing confusion and lethargy. Sedatives, such as benzodiazepines, should be avoided when possible. Anticholinergic drugs, such as some tricyclic antidepressants, antihistamines, antipsychotics, and benztropine, should be avoided Article 18. Heat-Related Illnesses edema -->oedema <clinical sign> The presence of abnormally large amounts of fluid in the intercellular tissue spaces of the body, usually applied to demonstrable accumulation of excessive fluid in the subcutaneous tissues. Oedema may be localised, due to venous or lymphatic obstruction or to increased vascular permeability or it may be systemic due to heart failure or renal disease. Collections of oedema fluid are designated according to the site, for example ascites (peritoneal cavity), hydrothorax (pleural cavity) and hydropericardium (pericardial sac). Massive generalised oedema is called anasarca. Origin: Gr. Oide ma = swelling (18 Nov 1997) syncope <clinical sign> A temporary suspension of consciousness due to generalised cerebral ischaemia, a faint or swoon. (19 Jan 1998) Ann N Y Acad Sci 1997 Mar 15;813:553-8 Related Articles, Books, LinkOut Heat intolerance induced by antidepressants. Epstein Y, Albukrek D, Kalmovitc B, Moran DS, Shapiro Y. Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. A case in which prescription medications induced heat intolerance which led to heat stroke is presented. A subject who suffered from depression and was treated with fluoxetine HCL (prozac) and lithium carbonate was engaged in mild intermittent work for 4 hours under hot/dry climatic conditions (Ta = 37 degrees C, rh = 15%). The subject lost consciousness, was hyperthermic and suffered from disseminated intravascular coagulation. A year later residual cerebellar symptoms were still evident and severe atrophy of the cerebellar tissue was demonstrated in a CT scan. It is suggested that drug-induced heat intolerance was the predisposing factor that reduced the patient ability to sustain exercise-heat stress, and under the favorable environmental circumstances led to excessive heat accumulation which ultimately caused heat stroke. This is the first description, to our knowledge, of heat intolerance of a patient treated by a combination of fluoxetine and lithium carbonate. PMID: 9100934 [PubMed - indexed for MEDLINE] Hosp Community Psychiatry 1982 Jun;33(6):474-6 Related Articles, Books, LinkOut The prevention and treatment of heatstroke in psychiatric patients. Bark NM. Heatstroke is a serious medical condition that affects people in all climates. There is some preliminary evidence that psychiatric patients and those on psychotropic drugs are particularly susceptible. The author discusses the signs and symptoms of heatstroke, the factors that lead to it, and the appropriate preventive and treatment measures that should be taken. He concludes that heatstroke in psychiatric patients is totally preventable, but that should heatstroke occur, quick recognition and treatment can prevent death. PMID: 6124500 [PubMed - indexed for MEDLINE] Am J Psychiatry 2000 Aug;157(8):1327-9 Related Articles, Books, LinkOut Heat intolerance in patients with chronic schizophrenia maintained with antipsychotic drugs. Hermesh H, Shiloh R, Epstein Y, Manaim H, Weizman A, Munitz H. Geha Psychiatric Hospital, Petah Tiqva, Israel. hermesh@... OBJECTIVE: Schizophrenia may be associated with hyperthermic syndromes such as febrile catatonia, neuroleptic malignant syndrome, and heatstroke. The authors hypothesized that an exercise-heat tolerance test would disclose abnormal thermoregulation in schizophrenic patients. METHOD: Seven male schizophrenic outpatients in remission maintained on depot antipsychotic treatment and eight healthy comparison subjects completed a heat tolerance test that consisted of two 50-minute bouts of walking a motor-driven treadmill at 40xC (relative humidity=40%). RESULTS: A significantly higher rise in rectal and skin temperatures was observed in the patient group. No differences in heart rate, blood pressure, or perspiration were detected. CONCLUSIONS: Schizophrenic patients maintained on antipsychotic drugs exhibit impaired heat tolerance. Possible explanations are a reduced ability to convey heat from the body's core to the periphery with or without excessive heat production. The hyperthermic response to the heat tolerance test may reflect a dysfunction associated with schizophrenia, a neuroleptic-induced side effect, or both. PMID: 10910799 [PubMed - indexed for MEDLINE] Lancet 1996 Apr 13;347(9007):1016 Related Articles, Books, LinkOut A depressed workman with heatstroke. Albukrek D, Moran DS, Epstein Y. IDF Medical Corps, Institute of Military Physiology; and Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. PMID: 8606565 [PubMed - indexed for MEDLINE] Prog Brain Res 1998;115:193-204 Related Articles, Books, LinkOut The effects of drugs on thermoregulation during exposure to hot environments. Lomax P, Schonbaum E. School of Medicine, University of California, Los Angeles 90024, USA. Publication Types: Review Review, Tutorial PMID: 9632937 [PubMed - indexed for MEDLINE] Ned Tijdschr Geneeskd 1995 Jul 8;139(27):1391-3 Related Articles, Books, LinkOut Comment in: • Ned Tijdschr Geneeskd. 1996 Feb 17;140(7):388. [Psychiatric drugs as risk factor in fatal heat stroke] [Article in Dutch] Fijnheer R, van de Ven PJ, Erkelens DW. Afd. Interne Geneeskunde, Academisch Ziekenhuis, Utrecht. Two men aged 33 and 31 years suffered a fatal heat stroke on a warm summer day. One of them used pimozide and clomipramine, the other zuclopenthixol, dexetimide, droperidol, promethazine and propranolol as psychiatric medication. Both of them had a body temperature > 42.3 degrees C, without perspiring. At first only a comatose situation with practically normal laboratory values existed; this was rapidly followed by massive liver damage, disseminated intravascular coagulation, anaemia, thrombopenia and acute renal failure. In spite of adequate and rapid treatment these complications were fatal. Both patients used medication with an antidopaminergic and anticholinergic (side) effect. The set point of the temperature regulation centre can be elevated by the antidopaminergic activity of antipsychotics. Use of anticholinergic medication can disturb the thermoregulation via inhibition of the parasympathicomimetically mediated sweat secretion. It is recommended to point out the danger of unusually high outdoor temperatures to patients using this medication. PMID: 7617062 [PubMed - indexed for MEDLINE] : Ned Tijdschr Geneeskd 1995 Aug 26;139(34):1759-60 Related Articles, Books, LinkOut Comment on: Ned Tijdschr Geneeskd. 1995 Jul 8;39(27):1391-3 [Psychiatric medication as risk factor for fatal heat collapse] [Article in Dutch] Conemans JM. Publication Types: Comment Letter PMID: 7566248 [PubMed - indexed for MEDLINE] Chest 1981 Aug;80(2):244-5 Related Articles, Books, LinkOut Heat stroke related to psychotropic medications and prior history of heat stroke. Caldroney RD. Publication Types: Letter PMID: 7249779 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1983 Feb;46(2):183-5 Related Articles, Books, LinkOut Cerebellar syndrome following neuroleptic induced heat stroke. Lefkowitz D, Ford CS, Rich C, Biller J, McHenry LC Jr. We report a patient in whom extreme hyperthermia, rhabdomyolysis, acute renal failure and a residual pancerebellar syndrome occurred while taking a combination of perphenazine and amitriptyline. We postulate that impaired thermoregulation due to psychotropic drugs was responsible for the development of heat stroke and that the cerebellar syndrome resulted directly from the elevated temperature. PMID: 6842224 [PubMed - indexed for MEDLINE] Minn Med 1977 Feb;60(2):103-6 Related Articles, Books, LinkOut Heat stroke associated with medications having anticholinergic effects. BE, Manoguerra AS, Lilja GP, Long RS, Ruiz E. PMID: 840206 [PubMed - indexed for MEDLINE] J Neurol Neurosurg Psychiatry 1987 Jul;50(7):937-8 Related Articles, Books, LinkOut Heat stress and neuroleptic drugs. Tacke U, Venalainen E. Publication Types: Letter PMID: 2887638 [PubMed - indexed for MEDLINE] J Clin Psychiatry 1982 Sep;43(9):377-80 Related Articles, Books, LinkOut Heatstroke in psychiatric patients: two cases and a review. Bark NM. Two fatal cases of heatstroke in psychiatric patients are described. A literature search revealed published reports of heatstroke involving 51 psychiatric patients, 22 of whom died. The mean age of these patients was 44 years; the majority has schizophrenia. Almost all were male and were taking antipsychotic or other drugs with anticholinergic effects. The implications for prevention, recognition, and treatment are discussed. PMID: 6126476 [PubMed - indexed for MEDLINE] Ann Anesthesiol Fr 1979;20(8):709-16 Related Articles, Books, LinkOut [Heatstroke among psychiatric patients under neuroleptic therapy. Apropos of 2 fatal cases] [Article in French] Ducrot P, Jouan JC, Sala JP, Mathon J. Heat stroke is uncommon in temperate climates but may be favourised by drug treatment. A report of two cases of fatal hyperthermia occuring in patients treated with neuroleptic drugs and during a heat wave is followed by a discussion of the characteristics which may be used to differentiate heat stroke from the hyperthermia of malignant twenty cases. It indicated that high degree of severity of this type of heat stroke, in great part related to the high prevalence of massive inhalation. The action of neuroleptics is very probably central by an effect upon the thermostat and also by changes in behaviour. The role of associated anti-parkinsonian agents is discussed. A review of treatment emphasises its difficulties. Publication Types: Review PMID: 44988 [PubMed - indexed for MEDLINE] 1: Gen Hosp Psychiatry 1985 Oct;7(4):361-3 Related Articles, Books, LinkOut Heatstroke in a chronic schizophrenic patient treated with high-potency neuroleptics. Lazarus A. A fatal case of heatstroke occurred in a chronic schizophrenic patient treated with high-potency neuroleptics. The author differentiates heatstroke from other hyperthermic syndromes related to treatment with major tranquilizers and suggests that an awareness of factors that predispose psychiatric patients to the development of heatstroke may aid in its prevention. PMID: 2866145 [PubMed - indexed for MEDLINE] Pitt DC, Kriel RL, Wagner NC, Krach LE. Related Articles Kluver-Bucy syndrome following heat stroke in a 12-year-old girl. Pediatr Neurol. 1995 Jul;13(1):73-6. PMID: 7575855 [PubMed - indexed for MEDLINE] Pediatr Neurol 1987 May-Jun;3(3):162-5 Related Articles, Books, LinkOut Kluver-Bucy syndrome in children. Tonsgard JH, Harwicke N, Levine SC. Department of Pediatrics, University of Chicago, IL 60637. Kluver-Bucy syndrome is an uncommon syndrome of behavioral abnormalities following bilateral temporal lobe injury. Only four children have been reported previously with this syndrome. We report three additional pediatric patients who developed Kluver-Bucy syndrome following hypoxic insults. In two patients, features of the syndrome were transient. Problems in intermediate memory were present in each patient. Behavioral abnormalities did not respond to the medications administered. Our experience suggests that Kluver-Bucy syndrome may occur more commonly in children than was suspected previously, especially following hypoxia. PMID: 3508062 [PubMed - indexed for MEDLINE] J Neurosurg Sci 1997 Sep;41(3):269-72 Related Articles, Books, LinkOut The Kluver-Bucy syndrome. Goscinski I, Kwiatkowski S, Polak J, Orlowiejska M, Partyk A. Jagiellonian University, Medical Faculty, Department of Neurotraumatology, Krakow, Poland. Evolution of psychological disorders following head injury including memory disorders and other cognitive ones are common. The best known are psychiatric disturbances of various kind after lesions of frontal lobes. Cognitive, behavioural and emotional disorders are not usually seen in patients with bilateral temporal lesions. In our Department of Neurotraumatology we observed 4 patients with post-traumatic lesions localized bitemporally. They developed Kluver-Bucy syndrome--rarity in human pathology--with combination of three or more the following syndromes: increased oral activity, hypersexuality, hypermetamorphosis, memory disorders, placidity, loss of people recognition, bulimia. Several symptoms responded dramatically to carbamazepine. We conclude that it may be a useful agent in treatment of this unusual syndrome. PMID: 9444580 [PubMed - indexed for MEDLINE] Am Fam Physician 1998 Sep 1;58(3):749-56, 759 Related Articles, Books, LinkOut Heat-related illnesses. Barrow MW, KA. State University School of Medicine, Dayton, Ohio, USA. Heat-related illnesses cause 240 deaths annually. Although common in athletes, heat-related illnesses also affect the elderly, persons with predisposing medical conditions and those taking a variety of medications. Symptoms range from mild weakness, dizziness and fatigue in cases of heat edema, to syncope, exhaustion and multisystem complications, including coma and death, in cases of heat stroke. Milder heat-related symptoms can be treated with hydration, rest and removal from the hot environment. Heat stroke, a life-threatening problem, must be treated emergently. Prompt recognition is critical since rapid cooling is the cornerstone of treatment and must not be delayed. Fluid resuscitation with dextrose and normal or half-normal saline is also important. These therapies should be instituted while the patient is being stabilized. Heat illness may be prevented by recognizing which individuals are at risk, using appropriate hydration and paying attention to acclimatization and environmental conditions. Preventive care should include drinking plenty of fluids before, during and after activities, gradually increasing the time spent working in the heat and avoiding exertion during the hottest part of the day. Publication Types: Review Review, Tutorial PMID: 9750542 [PubMed - indexed for MEDLINE] http://abcnews.go.com/sections/living/Healthology/heatwave_dangers.html Heat Wave Dangers A. Finkel, MD, Massachusetts General Hospital Most often, heat-related illnesses are preventable conditions. However, they can have significant consequences, including death, if left untreated. The illnesses are traditionally divided into two main categories-heat exhaustion and heat stroke. These conditions can overlap in many ways and exist on a continuum of severity. As a patient's body temperature rises, heat exhaustion can rapidly progress to heat stroke. Heat Exhaustion and Heat Stroke Heat exhaustion develops when the body encounters excessively high temperatures that it is not used to managing. It occurs at body temperatures that are very high, but usually less than 40 degrees Celsius, or 104 degrees Fahrenheit. The symptoms of heat exhaustion are not very specific, but ultimately relate to a state of dehydration, which is the condition's primary characteristic. Symptoms may include weakness, headache, and nausea. Heat stroke is severe injury from high body temperatures that causes damage to many organs, particularly the central nervous system, which include the brain and spinal cord. In contrast to heat exhaustion, patients suffering from heat stroke will have temperatures that are usually greater 104 degrees. Heat stroke may be divided into two categories-exertional and classic. Exertional heat stroke Exertional heat stroke patients are usually people who are exercising in excessively warm conditions. Their bodies cannot manage the stress of the physical activity and the hot environment together. Classic heat stroke Classic heat stroke patients are often elderly or debilitated people who are in warm environments for too long. The elderly are especially vulnerable to the heat, as the body is less and less able to handle heat as it ages. Elderly people may also have pre-existing illnesses that make them more susceptible to heat stroke, or they make take medications that affect the body's ability to manage hot temperatures. Elderly people, who, for economic reasons, are not able to get out of the heat, are at great risk for heat stroke. Heat Transfer In order to understand heat-related illnesses you need to know something about the way the body normally gets rid of heat. There are four ways the body transfers heat: radiation, evaporation, conduction, and convection. Radiation Radiation occurs when the body turns heat into electromagnetic waves. In other words, waves of heat can escape from the body directly into the surrounding air. This is the primary way that human beings are able to lose heat from their bodies in very hot environments. Evaporation Evaporation is the transfer of heat that occurs during the transformation of liquid to gas. Evaporation of sweat (even of sweat you cannot feel, called insensiblelosses) is another significant method that the body uses to cool down. Convection and conduction Convection and conduction are secondary ways for the body to lose heat after radiation and evaporation. Convection is the passage of heat into the air and into the vapor that surrounds the body. It is different from evaporation in that the heat does not transform to the gas phase, as it does in evaporation. Conduction is the transfer of heat through physical contact. What Happens When it Gets Too Hot In hot environments, the body initiates several processes to lose heat. First, the anterior hypothalamus, the body's thermostat in the brain, signals the body to open up blood vessels near the skin's surface so that heat can be transferred outside by the methods listed above. This vessel dilation is possible because blood is shunted away from the body's core. The hypothalamus also mediates sweating and tells the body to respond to the heat by taking off clothes and seeking a cooler environment. When it becomes too hot, however, the body's ability to cool down becomes overwhelmed. Symptoms like fatigue, headache, muscle aches, confusion, and even coma can occur, depending on the severity of the condition. This overwhelming of the body's means of handling heat can be caused by a very warm environment or excessive exercising in the heat, as discussed before. Also, though, patients may get overheated because of certain illnesses like hyperthyroidism (high thyroid hormone level) or infections causing fever. Additionally, some medications can cause high body temperatures. A class of drugs called anticholinergics can decrease the body's ability to sweat and, therefore, to lose heat. Other drugs called sympathomimetics can decrease skin vessel dilation. There are other classes of drugs that may also interfere with body temperature regulation through various, sometimes complicated, mechanisms. Symptoms and Signs There are a variety of symptoms associated with heat-related illnesses. Heat exhaustion patients may have vague complaints of symptoms that come on slowly. These can include: • Headache • Weakness • Lightheadedness • Muscle aches • Muscle cramps • Agitation Heat stroke patients can have the same complaints as heat exhaustion patients, but they also suffer central nervous system problems, which can include: • Confusion hallucinations • Bizarre behavior • Seizure • Coma It was once thought that heat stroke patients did not sweat, but this inability to sweat is variable, and often strikes the patient at the latest stages of the condition. Heat stroke patients, because of the resulting multi-organ damage, may also complain of blood in the urine or stool, decline in the amount of urine produced and shortness of breath, among other problems. Other symptoms There are secondary categories of heat-related illnesses to watch out for: • Heat syncope occurs when a person overheats and then faints. • Heat cramps are muscle contractions associated with electrolyte or mineral abnormalities caused by the heat. • Heat edema is characterized by swelling in the arms and legs because of the heat. • Prickly heat is a heat rash that is red and very itchy. Treatment There is a lot that you can do for a person suffering from a heat-related illness. If you see someone who appears to be suffering from a heat-related illness, you should call for help immediately. In the most rare, severe cases, you should start cardiopulmonary resuscitation (CPR), if necessary. If the person is not a trauma patient (has not been in an accident, fight, or fall), you should move the individual from the hot environment to a cooler location. Next you can sprinkle lukewarm water on the skin and fan the patient; this will encourage evaporation. You can also apply ice packs to the neck, underarms, and groin. In the emergency room Once a patient has been taken to the emergency room, the cooling process will be continued. The doctor may use a cooling blanket and some other more aggressive methods, but in general, treatment is similar to the methods that should be initiated immediately, including fanning and ice packs. The doctor may order tests to assess organ damage. These tests can include electrolytes or minerals, blood-clotting tests, a urine analysis, creatine phosphokinase (a muscle enzyme quantification), and a head computed tomography (CT or cat) scan. Heat stroke patients are admitted to the intensive care unit. Heat exhaustion patients are admitted to a regular floor bed in the hospital. When patients are released from the hospital, they should have a place to go to avoid the heat, and they must be able to rehydrate themselves. If caretakers are aggressive with these cooling techniques before delivering the patient to the hospital, and the emergency department is able to treat any related organ damage, then there is a good possibility that the prognosis will be excellent. Prevention Heat-related illnesses are often preventable. When hot weather is expected, the elderly and debilitated must be ensured access to cool, air-conditioned shelter. People should be encouraged to wear light-colored, loose clothing and bathe in tepid water. Also, hydration is critical, and people in hot weather should increase their fluid intake substantially. To avoid exertional heat stroke, athletes should not exercise in extreme heat, and coaches should be aware of the symptoms of heat-related illnesses. Athletes also must stay well-hydrated. Summary Heat-related illnesses are a continuum of conditions but have traditionally been divided into heat exhaustion-characterized by dehydration-and heat stroke, in which organs, particularly the central nervous system, are damaged. Heat exhaustion patients may have vague complaints like weakness, nausea and headache, whereas heat stroke patients often have these symptoms plus confusion or hallucinations. Heat-related illnesses present a potentially severe-even fatal-set of conditions that can often be prevented if treated early and aggressively. Learning about the symptoms and preventive care can help you help someone else. Can You Handle the Heat? Copyright 2001 Healthology, Inc. All rights reserved. This material may not be published, broadcast, rewritten or redistributed _________________________________________________________________ Send and receive Hotmail on your mobile device: http://mobile.msn.com Quote Link to comment Share on other sites More sharing options...
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