SUNSTROKE.
The terms “sunstroke,” “insolation,” “coup de soleil,” are applied to conditions induced, not alone by exposure to the rays of the sun, but rather by a combination of great heat with other exciting causes. They are used to designate attacks occurring in very hot weather after exposure to solar or other sources of extreme heat. The striking and usual phenomena are exhaustion, unconsciousness, stertorous respiration, and death, occurring by syncope, within a few moments or hours. In a number of cases the symptoms of cerebral apoplexy with death by coma are present.
In others, the condition seems one of complete exhaustion. The majority of cases seem to be a combination of these several conditions, with death resulting from syncope.
The ordinary phenomena of the attack are pain in the head, hurried respiration sometimes stertorous, violent beating of the heart with failing of its power, oppression within the chest and, occasionally, nausea and vomiting. The pupils are sometimes dilated and sometimes contracted, but in all cases exhibit lessened sensitiveness to light. The suddenness of the attack modifies the symptoms developed.
Pathological Conditions.
These are exhaustion with syncopic tendency and a rapid rise in the temperature of the body to a point destructive to the activity of the nervous centres. This is accompanied by an abnormal condition of the blood, resulting from loss of its watery portions, with retention of effete products and impaired aeration. A tendency to general stasis, specially marked by congestions of the lungs and brain, is present. The change in the blood is a very important factor. In some cases, not fatal at the outset, this induces a septic condition.
The greatly elevated temperature of the body undoubtedly produces certain modifications which type it, in some respects, as a febrile disease; but this, with the septic tendency due to blood changes, is not sufficient to designate it as a purely “thermal fever,” as some have claimed. It is something more than this.
Sunstroke occurs more commonly in tropical than temperate climates;[694] and usually in the day-time, at the period of greatest solar activity, those attacked being engaged in labor involving considerable exertion. It occasionally, though rarely, occurs at night. The military service affords abundant opportunity for observation. Here the seizures are on the march, rarely in camp. Fatigue, prolonged and extreme exertion, ill-adjusted clothing and accoutrements, with the deprivation of cool water, are fully as active factors as the heat of the sun. The death-rate ranges between forty and fifty per cent, the mild cases being excluded. Death in some cases is marked by syncope, in others by apnœa, though the majority seem to die by a combination of both, as in most cases the pulmonary congestion is more or less pronounced. Undoubtedly the character of the symptoms and mode of death are influenced, in many cases, by individual tendencies leading to apoplectic conditions or to cardiac or other complications.
Treatment.
This must be adjusted to the pathological conditions of the patient. As already indicated, two classes of cases are met: one marked by exhaustion, with tendency to death by syncope; the other, a state of or tendency to cerebral congestion or apoplectic conditions. Exactly opposite methods of treatment are demanded. In the first, frequency and feebleness of the heart’s action, with faintness of the heart sounds and embarrassment of respiration, indicate the tendency to death by nervous exhaustion, and must be met by placing the patient in a condition of absolute rest and quiet in a cool place. Stimulants must be promptly administered, though cautiously on account of the tendency to nausea and vomiting. Hypodermic injections of alcohol or ether, or rectal enemata of turpentine, alcohol, or other stimulants, afford means of securing speedy effects when the stomach is irritable. Carbonate of ammonia and other cardiac stimulants are recommended. Depleting agents, or such as prove depressing, are to be avoided. In some cases, hypodermic injections of small doses of morphine prove beneficial. Individual cases must modify therapeutic procedures.
In the second class of cases the tendency to cerebral congestion indicates sedative and depleting procedures. Blood-letting has been recommended by some authors, if employed with extreme judgment and discrimination.[695] Cold applied to the head and also to the whole body by rubbing with ice[696] or by effusion and the wet sheet, or other means, is indicated if the temperature is high (104° to 105° F.). Active catharsis, by promptly acting purgative enemata, is also to be resorted to in most cases. The convulsions occurring in some cases are successfully modified and controlled by inhalations of small quantities of chloroform.
Post-Mortem Appearances.
These, though not clearly characteristic, are pronounced. In some cases no distinct conditions are found.[697] Local congestions are present in nearly all cases. Upon the skin are found petechial and livid spots, pallor being occasionally noted. Ecchymoses and subserous hemorrhages are also common. These conditions have been described as resembling those of spotted typhus (Levick).
Rigor mortis is marked and occurs early, putrefaction beginning soon after death. The lungs are highly congested and often œdematous, and effusions of serum are frequently found in the pleural cavities.[698]
The heart is usually changed in color and consistence, with the left ventricle contracted and the aorta empty, while the right ventricle and pulmonary arteries are dilated and engorged. The blood is fluid and dark.[699] The large vessels of the pia and dura are full of dark blood. Congestion of the cerebral mass is not always noted. The ventricles contain serum; and extravasations of blood into the cervical sympathetic ganglia and vagus are sometimes found. The kidneys are usually moist and œdematous; the liver and spleen congested and dry.