Heat-exhaustion, then, is one form of what, when the subject of it happens at the time to be exposed to the sun, is called "sun-stroke," or when the patient happens to be at the time under cover, is called " heat-stroke." In nine cases out of ten this sun-stroke, or heat-stroke, simply means syncope; syncope caused by solar or atmospheric heat, or a combination of these, acting on a body whose resistance has been impaired by disease, or by trying, unphysiological conditions. This form of heat-stroke, consequently, has no special geographical distribution and no special morbid anatomy or pathology. For obvious reasons it is most apt to occur in warm weather, and in tropical climates; and on this account its recognition, prevention, and treatment have special claims on the student of tropical medicine.
Symptoms.— When attacked with heat-exhaustion the patient feels giddy, and perhaps staggers and. falls. He is pale; his pulse is small, soft, and perhaps fluttering; his breathing is shallow, perhaps sighing, never stertorous; his pupils are dilated; his skin is cold; his temperature is subnormal; and he may be partially, more rarely wholly, unconscious. Usually after a short time he gradually recovers; very likely with a splitting headache and feelings of prostration. In a small proportion of cases the faint is not recovered from, and death ensues.
Treatment.— In syncopal heat-stroke the patient should be laid at once on his back in a cool, airy, and shaded place. His clothes should be loosened, a little water dashed on his face and chest, and ammonia held to his nostrils. If necessary, a stimulant may be given by the mouth, or injected into the rectum or hypodermically. It is a mistake to douche these cases too freely. The object is rather to stimulate than to depress.
SIRIASIS
Definition.— An acute disease developing in the presence of high atmospheric temperature, and characterized by sudden incidence of hyperpyrexia, coma, and extreme pulmonary congestion.
