HEAT SYNCOPE AND HEAT STROKE 391 



cold skin, temperature normal or sub-normal, partial or complete 

 unconsciousness. Headache is common. 



Death is the exception. 



There are usually no after symptoms. 



TREATMENT. 



Open air, apply cold water to the face, loosen the clothing about 

 the chest. Ammonia salts to the nose. Brandy to drink. Injection 

 of strychnine when necessary. 



Bed, hot bottles and stimulants if the temperature is sub-normal. 



(2) HEAT STROKE (Sunstroke). 



(A) Direct. 

 DEFINITION. 



A febrile condition resulting from exposure to the direct rays of 

 the sun accompanied by pulmonary congestion, convulsions, coma, 

 recovery or death. 



iETIOLOGY. 



A dog shaved and exposed to the direct rays of the sun, dies. If 

 it is covered with coloured glass, nothing happens. 



This variety is common in Persia and India, but may occur any- 

 where if the temperature is high enough. 



The theories as to the causation are : — 



(i) Caloric, a hyperpyrexia! condition. 



(2) Actinic, due to the sun's chemical rays. 



(3) Microbic, due to some germ (Sambon). 



(4) Toxic, due to poisons generated by the excessive heat. 

 Manson's classification is as follows : — 



(a) Superheating of the blood. 

 (h) Paralysis of the thermic centres causing: — 

 (i) Excessive production of heat. 



(2) Retention of body heat. 



(3) Expansion of cerebro-spinal fluid causing pressure on tb,e 



brain. 



(4) Vasomotor paralysis. ^ 



(5) Paresis of heart ganglia. 



(6) Excess of carbon dioxide in the blood. 



(7) Coagulation of the mvosin. 



(8) vSuppression of sweat. 



(9) Deficient serositv of the blood. 



The thick skull and black skin of negroes are protective. 



