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Hyperthermia Zhang Yinglan MD, Associate chief physician Emergency Department Longhua Hospital Affiliated Shanghai University of TCM What is hyperthermia? It is an acute heat injury disease resulting from prolonged exposure to high environmental temperature which causes a dysfunction of the temperature-regulating mechanism and excessive loss of water-electrolyte of the body. Causitive Factors high temperature climate dry-heat working condition and high humid-warm environment dysfunction of the temperature-regulating mechanism • increased heat production • poor heat adaptation • impedient heat dissipation Causitive Factors High temperature condition temperature>32℃ humidity> 60% poor ventilation Long time or high-intensitive work Etiological Factors Obtain excessive external heat Increased heat production Iimpedient heat dissipation Dysfunction of the sweat gland Severe potassium deficiency pathogenesis Heat production Oxidative metabolism Muscle contraction Heat dissipation (15-25℃) Radiation 60% Evaporation 25% Convection 12% Conduction 3% Regulation of heat production and dissipation Radiation Convection & •the major way of heat dissipation •depends on the difference between the body surface and environmental temperature( 15-25℃ →60%, 33℃ →0% ) the most heat dissipation part of the body is head(50%), then hands and feet •depends on the air flow rates •the conduction power of water is 240 times than the air Conduction Evaporation •1g water evaporation for 2.4kj(0.58kcal)heat dissipation •more humidity less evaporation The influence of hyperthermia on the human body central nervous system inhibiting effect • inattention • slow in reacting • decreased accuracy and Coordination of action dysfunction • delirium、 mania • coma cardiovascular system arrhythmia heart failure decreased cardiac output respiratory system respiratory alkalosis ARDS water-electrolyte metabolism loss of water and sodium and chlorinum urinary system reduction in renal blood flow and glomerular filtration rate • proteinuria and cylindruria rhabdomyolysis(横纹肌溶解) • myoglobinuria(肌红蛋白尿) • acute renal failure Diagnosis Severe heatstroke Mild heatstroke Premonitory heatstroke Prodrome High temperature environment Thirsty、fatigue、 excessive sweating、 dizziness、 headache、palpitation、nausea… The body temperature is about normal or slightly high Mild Hyperthermia The exacerbation of premonitory hyperthermia The early stage of dysfunction of the circulation: flushed face or pale complexion、 dysphoria or apathia 、nausea and vomiting 、 sweating 、 clammy skin, 、thin and rapid pulse、 hypotension 、 increased heart rate The body temperature is slightly increased Severe Hyperthermia type heat cramps heat exhaustion heat stroke high temperature heat cramps sweating a lot excessive loss of water and salinity supply more water but less salinity hyponatremia and hypochloremia muscle cramp、pain(water loss > salinity loss) excessive expansion of peripheral vascular heat exhaustion collapse、shock temperature>42℃ → protein denaturation body temperature>50℃ → all cell death a few minutes later during the autopsy, pathological change can be seen in the brain、 neurocyte 、 cardiomyocytes 、lung、liver、kidney and hemorrhagic spots can be found in the pleura、 peritoneum 、small intestine,etc body heat stroke Clinical symptoms of severe hyperthermia Heat cramps it refers to a severe muscle cramp and contraction pain (the muscle of four limbs and abdomen) it happens at the beginning of the hot season and before the heat adaptation of the body young people who do manual work under the high temperature circumstance and sweat a lot Heat exhaustion acute onset dizziness, headache, suddenly faint , pale complexion , cold sweat in the skin, weak or slow pulse, hypotension but with normal pulse pressure awake after lie on the back or leave the high temperature environment old people or individuals with heat intolerance Heat stroke typical symptoms:hyperpyrexia , anidrosis , disturbance of consciousness prodrome:fatigue, dizziness, headache, nausea, sweat reduced body temperature increases rapidly(>41℃) → somnolence, apathy, coma hot and dry skin ,no sweat, flushed or pale skin , or even cyanosis Heat stroke pulse quicken , increased pulse pressure , decreased blood pressure arrhythmia fast and shallow breathing ,Chyne-Stokes respiration muscle twitches pupil contraction ,pupillary light reflex disappear Heat stroke shock heat stroke heatfailure arrhythmia pulmonary edema cerebral edema liver and kidney failure ARDS gastrointestinal bleeding DIC… Laboratory examination Heat cramps blood natrium ↓ blood chlorine ↓ ucre urine creatine ↑ Heat exhaustion hematocrit (HCT) ↑ hyponatremia 、 hypokalemia 、slight azotemia or abnormal liver function Heat stroke hyperkalemia, hypercalcemia, hemoconcentration, leukocytosis , thrombocytopenia Cr、BUN、AST、ALT、LDH、CPK ↑ proteinuria , cylindruria, myoglobinuria , acidosis EKG Diagnosis Heat cramps or exhaustion exposure history to high temperature environment symptoms:sweat a lot, muscle cramps, postural syncope , transient fall of blood pressure laboratory examination Heat stroke three characteristics • hyperpyrexial fever dry and hot skin severe central nervous system symptoms • • acute onset causitive factors Differential diagnosis diseases cause high fever and coma • cerebral malaria Japanese encephalitis meningitis acute cerebrovascular disease organic phosphorus pesticide poisoning … • • • • • Evaluation of vital signs 1 causes duration of the injury start time of rescue evaluate 2 severity body temperature disturbance of water and electrolyte evaluate 3 consciousness pulse respiratory bloodpressure muscular tension urine volume observation Treatment On-site treatment leave the high temperature environment immediately have a quiet rest in a shelter, loosen the clothing drink some cold salty water NS、GS、KCL ivgtt (for a circulatory failure patient) no massage for the muscle cramp and contraction pain electrolyte supplement a positive rescue for a heat sroke patient Hypothermia therapy lower the temperature of environment cool and ventilated place indoor temperature <20 oC lower the temperature of the body surface rub the body surface put the ice bag on the main artery(head, bilateral carotid artery, armpit, groin) avoid shivering cold bath lower the temperature of the central body temperature 5%GS 1000~2000mlivgtt (4-10oC) 10%GNS 1000ml enema (4-10oC) inject cold NS into the gastric tube drug hypothermia chlorpromazine 氯丙嗪 naloxone 纳洛酮 lower lower the body temperature till 38oC (rectal temperature) maintain the systolic pressure>90mmHg Emergency treatment a cool and ventilated environment cold salty drink Chinese patent medicine(rendan mini-pills, “ 10 drops ”, Huoxiangzhengqi tablets) acupoint massage with essential balm ( Taiyang(EX-HN5),Hegu(L14)) cold compress, alcohol bath 5%GNS1000-2000 ml ivgtt Prodrome & mild 急救处理 热 痉 挛 在补足体液情况下,仍有四肢肌肉抽搐和痉 挛性疼痛,可缓慢静注10%葡萄糖酸钙 10ml+维生素C 0.5。 Emergency treatment circulation collapse 5%GNS2000-3000ml ivgtt quickly vasopressor( dopamine, aramine) maintain the systolic pressure>90mmHg Emergency treatment heart stroke physical hypothermia drug hypothermia(chlorpromazine) naloxone treatment(naloxone 0.8mg +25% GS20ml iv) symptomatic and supportive treatment prevent from cerebral edema fluid infusion oxygen Emergency treatment ventilation low temperature hypothermia comprehensive and supportive treatment symptomatic treatment respiratory function circulatory function cerebral edema renal dysfunction hepatic dysfunction DIC water-electrolyte and acid-base balance intensive nursing prevention and treatment of multiple organs failure lower the central body temperature as soon as possible decrease the metabolic rate complication treatment Prognosis mortality:20% -70% the worst type:heat stroke sequela • mild neural dysfunction • several weeks of muscular weakness • permanent brain damage Prevention TCM treatment Heat-clearing drinks hawthorn tea(山楂汤) hawthorn 100g, dark plum 50g, feverfew20g iced water melon juice sweet mung bean soup and plum juice(绿豆酸梅汤) lotus leaf tea fresh lotus leaf10g, baizhu10g, huoxiang6g, gancao6g lonicera japonica tea(金银花汤) Chinese patent medicine mini-pills 人丹 “10 drops”(a popular medicine for summer aliments) 十滴水 essential balm清凉油 Rendan thank you!