heat stroke

Introduction

Introduction to heat stroke Heatstroke is a serious adverse reaction caused by the human body in a high temperature environment. The body temperature of a normal person is managed by the thermoregulatory centers of the cerebral cortex, the diencephalon, the medulla, and the hypothalamus. The heat generated by the human body is lost through conduction, radiation, convection and evaporation to maintain proper body temperature. When the outside temperature is too high, heat is prevented when heat is blocked for a long time, such as sun exposure, hot heat, or high temperature environment where air does not circulate. basic knowledge The proportion of illness: 0.023% Susceptible people: no specific population Mode of infection: non-infectious Complications: disturbance of consciousness coma brain edema respiratory failure shock acute renal failure heart failure headache

Cause

Cause of heat stroke

Ambient temperature is too high (20%):

The human body receives heat from the external environment, and in the environment with elevated atmospheric temperature (>32 °C), high humidity (>60%) and no wind, long-term work or strong physical labor, and lack of adequate heatstroke prevention measures, lack of Heatstroke is prone to heatstroke.

Increased body heat production (20%):

Such as heavy physical labor, fever, hyperthyroidism and the application of certain drugs (amphetamine), these factors can lead to heat stroke disease.

Heat dissipation barrier (10%):

Such as high humidity, obesity or poor ventilation.

Sweat gland dysfunction (20%):

Found in patients with systemic sclerosis, extensive skin burns, scar formation or congenital sweat gland deficiency.

Prevention

Heat stroke prevention

Prevention of heat stroke should fundamentally improve labor and living conditions, isolate heat sources, reduce workshop temperature, adjust schedules, supply 0.3% salty soft drinks, and promote prevention and treatment of heat stroke, especially early symptoms of heat stroke, and cardiovascular diseases. , high blood pressure, central nervous system diseases, obvious breathing, digestive or endocrine system diseases and liver and kidney disease patients should be listed as a contraindication to high temperature workshop employment.

Complication

Heat stroke complications Complications conscious disorder coma cerebral edema respiratory failure shock acute renal failure heart failure headache

1, cerebral edema consciousness disorder, coma is often one of the main symptoms of the elderly heat stroke treatment, severe pathological changes in the brain for the brain is congestion, edema and bleeding (fusion, diffuse or sputum). Cerebral edema in the case of clear consciousness or shallow disturbance of consciousness, clinical manifestations of intracranial hypertension, headache, often progressive, severe headache, vomiting and headache, can be sprayed, headache can be temporarily relieved after vomiting Visual papilledema, fundus vein blood stasis, pulsation disappeared, retinal edema, exudation, bleeding and other changes. In addition, double vision, slow pulse, increased blood pressure and disturbance of consciousness. Changes in vital signs are different levels of disturbance of consciousness, such as irritability, lethargy, and even coma, the deeper the coma, the worse the prognosis; respiratory difficulties, respiratory failure: circulatory disorders, shock, heart failure, persistent high fever, various cooling measures Invalid, central high fever. Indicates serious damage to the central nervous system.

Severe heat stroke, high fever, coma, after effective cooling measures, patients often get rid of coma within 4h, 24 hours after returning to normal rationality, if the patient's response to cooling measures is very small or unstable, always coma, suggesting that brain damage has been Reach an irreparable degree.

2, heart failure.

3. Respiratory failure.

4, acute renal failure severe heatstroke kidney damage, pathological changes for renal congestion accompanied by subcapsular, renal pelvis, renal interstitial hemorrhage. Clinical manifestations of less urine, urine routine protein, transparent cast and granular cast, pus cells and red blood cells. Shock and water, electrolytes and acid-base imbalance shock have a great impact on the prognosis of patients with severe heat stroke, especially in elderly patients. The occurrence of shock in heatstroke patients is related to brain edema, heart failure, respiratory failure, infection and hypovolemia. On the contrary, shock also increases the damage and failure of various organ functions.

Symptom

Heatstroke symptoms Common symptoms Fatigue Heat resistance Reduce skin Dryness Heat and heat failure Cold sweating Sweating Reduces dizziness and sputum

Heatstroke is divided into:

1, aura of heat stroke: under high temperature or sun exposure, dizziness, tinnitus, chest tightness, sweating, thirst, nausea and other symptoms, then as long as the environment is improved, rest, the symptoms will soon improve.

2, mild heat stroke: when the body temperature is higher than 38.5 ° C, in addition to the symptoms of aura of heat, there may be early symptoms of respiratory and circulatory failure. After timely processing, it will soon improve.

3, severe heatstroke: In addition to the above symptoms, body temperature can be as high as 40 ° C, and there are coma, paralysis and respiratory, circulatory failure, but also enthusiasm, leading to low blood sodium, low blood chlorine, low blood calcium and vitamin deficiency.

Examine

Heatstroke check

1, blood routine, urine routine, fecal routine.

2. Liver function, renal function, electrolyte and inorganic element detection.

3. Cardiovascular examination.

4. CT examination.

5. Detection of blood gas and acid-base balance indicators.

Diagnosis

Heatstroke diagnosis

diagnosis

The diagnosis of heat stroke can be based on the rise of body temperature, muscle spasm and/or syncope during labor and life in a high temperature environment, and should be diagnosed after excluding other diseases. The disease that needs special identification with heat-radiation disease is encephalitis, organic phosphorus. Pesticide poisoning, toxic pneumonia, bacillary dysentery, malaria. Heat exhaustion should be differentiated from gastrointestinal bleeding or ectopic pregnancy, hypoglycemia. Heat and abdominal pain should be differentiated from various acute abdomen.

According to China's "Diagnostic Standards for Occupational Heatstroke" (GB11508-89), heatstroke can be divided into the following three levels:

1. Aura of heatstroke is a symptom of normal dizziness, headache, thirst, sweating, general fatigue, palpitations, inattention, incoordination, etc. after a certain period of labor in a high temperature environment. The body temperature is normal or slightly elevated. .

2, mild heat stroke, in addition to the symptoms of threatened heat stroke, the appearance of flushing, a lot of sweating, rapid pulse and other performance, body temperature rose to above 38.5 °C.

3, severe heat stroke, including heat shock, enthusiasm and heat exhaustion.

The typical clinical manifestations of heat-induced disease are high fever (above 41 °C), no sweat and disturbance of consciousness, often working in high temperature environment for several hours or old age, and frail, patients with chronic diseases have heatstroke after several days of high temperature, and the symptoms of the pioneers are all over the body. Weakness, fatigue, dizziness, headache, nausea, reduced sweating, followed by rapid rise in body temperature, drowsiness, paralysis or coma, dry skin, burning, no sweat, flushing or paleness. Peripheral circulatory failure is purpura, rapid pulse, wide pulse pressure, low blood pressure, arrhythmia, fast and shallow breathing, Chen-Shi's breathing in the late stage, twitching of limbs and whole body muscles, pupil dilation, later expansion Responsive or disappeared to light, severe patients with shock, heart failure, pulmonary edema, cerebral edema, or liver, renal failure, disseminated intravascular coagulation, laboratory examination of increased white blood cell count and neutrophil ratio, urine Protein and cast, blood urea nitrogen, alanine and aspartate aminotransferase, lactate dehydrogenase, creatine phosphokinase and erythrocyte superoxide dismutase (SOD) increased, blood pH decreased, blood sodium, potassium decreased The electrocardiogram has arrhythmia and myocardial damage.

The enthusiasm often occurs in high-temperature environment after strong physical labor, patients often have a lot of sweating, then limb muscles, abdominal wall muscles, and even gastrointestinal smooth muscles have paroxysmal spasms and pain, laboratory tests for blood sodium and chloride Lower, creatinine increased.

Heat exhaustion often occurs when the patient is not suitable for heat. There is often no excessive heat accumulation in the body. The patient has headache, dizziness, nausea, thirst, chest tightness, pale face, cold sweat, weak pulse or slow, low blood pressure. There is syncope, and there are hands, foot convulsions, severe circulatory failure, laboratory tests for low sodium and low potassium.

The main pathogenesis and clinical manifestations of heat-induced disease, enthalpy and heat failure vary, but there are two or three clinical coexistences that cannot be completely distinguished.

Late proof of physical labor at high temperatures, before the clinical symptoms of heat stroke, a group of acute phase response proteins that reflect stress in the body - -acid glycoprotein, haptoglobin, copper Protein and alpha-antitrypsin have increased, suggesting that the body has been affected by heat.

Differential diagnosis

1, senile pneumonia often coexist with heat stroke, its clinical manifestations are diverse, and even lack of breathing and other symptoms, such as cough, sputum, etc., more lack of typical pneumonia signs. Can be expressed as loss of appetite, disturbance of consciousness or mental abnormalities, some manifested as palpitations, chest tightness, tachycardia arrhythmia (atrial premature beats, ventricular premature beats) and other fever, body temperature is below 39 ° C, individual can be no fever only Excessive sweating, peripheral blood, white blood cells normal or elevated, classification with neutral increase is obvious, easy to merge with water, electrolyte imbalance and acid-base balance disorders, shock, arrhythmia and respiratory failure, heart failure, early respiratory sounds weakened, There may be a little wet voice, more common in one part of the local lung at the bottom, which occurs on the basis of chronic bronchitis, and there may be a variety of dry and wet voices in both lungs. The above lung signs can provide clues to pneumonia, and X-ray examination can confirm the diagnosis.

2, cerebral hemorrhage often with heatstroke coexistence of the disease onset, sudden symptoms, vomiting, progressive speech and coma, snoring, urinary incontinence, may have convulsions, thalamic hemorrhage involving the lower thalamus, cerebral hemorrhage is characterized by high fever , coma, head CT can be clearly diagnosed.

3, high blood sugar, the elderly impaired glucose tolerance, the incidence of diabetes over 50 years old increased significantly, the incidence rate of 50 years or older is as high as 40%, and patients lack of symptoms, urine sugar is often negative. Heat stroke will make the condition worse, and the cause of recessive diabetes will be affected. The stress state of severe heatstroke can also increase blood sugar, but generally does not exceed 15-20 mmol/L.

4, diabetic ketoacidosis and non-ketotic hyperosmolar coma in the disease induced by the infection in the first place, fever is one of the main symptoms, infection is more common in lung infection, heat stroke is also one of the predisposing factors . Often seen in a coma, loss of water, shock. Non-ketotic hyperosmolar coma is mostly seen in the elderly, and half of them have no history of diabetes. Laboratory tests can confirm the diagnosis.

Was this article helpful?

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.