The appetite fails at once, or, more frequently, after a few days, in the acute fevers, and with this failure the amount of food taken is diminished. With the disappearance of the adipose tissue, and the ema ciation of the muscular and osseous systems, if the quantity of water taken is diminished, a certain drying out of the organism occurs; but this is much more the case when, with a decreased intake, there is an increase in the consumption of fluid by the body. While, as a rule, in the acute febrile diseases, a plentiful supply of fluids seems to be indi cated to maintain the secretions of the glands and to prevent a stasis of the excretions from the intestines and kidneys, it is not always a good policy to try to prevent loss of weight by increasing the quantity of food, even aside from the fact that a full (het is unpleasant to the patient and but poorly tolerated. A temporary loss of weight within certain limits in a previously well nourished child is hardly a disadvantage, since clur ing convalescence the appetite will be so much greater that the loss will be more than compensated. There is no necessity, therefore, in pneu monia, scarlet fever, or measles, for urging and bothering a child to take nourishment; whereas, in typhoid, cerebrospinal meningitis, or suppura tive processes generally, where the duration of the disease is uncertain, a good nourishing diet is demanded from the outset. It is hardly neces sary to discuss the fact that an afebrile disease unaccompanied by wasting, such, for example, as depends upon some surgical, mental, or nervous condition, requires a moderate rather than a full diet, inasmuch as rest in a warm bed is accompanied by a diminished expenditure of energy. A full diet is not always indicated or of use in the chronic dis eases, even though it is frequently advised in a theoretical consideration of the subject. Omitting from consideration that form of idiocy which is characterized by an excess of fat, abundant nutrition cannot bring about an improvement in organic nervous diseases, in neurasthenia, hysteria, or other functional diseases, excepting when the nervous con dition is caused or increased by bodily inanition. A highly nutritious diet (suitably planned) forms an essential part of the treatment. in a few of the chronic diseases; i.e., infantile atrophy, exhaustion, the nutri tional disturbances of older children, and in scrofulo-tuberculosis. It is not to he expected that an immediate curative effect will be obtained in such affections as, for instance, rickets, syphilis, and diseased condi tions of the blood. Moreover, the final aim of the treatment has not been attained with overfeeding alone (as shown by an increase in weight). Now and again, however, this is a favorable prognostic sign, since the possibility of increasing the weight usually bespeaks the absence of a serious condition whose outcome will be unfavorable. There are, how ever, exceptions to this rule.
We will not consider here the question of nourishment in diseases of time gastro-intestinal tract or in the atrophic condition of infancy, but will discuss more minutely the indications for a full diet and the quantity and quality of the food of which it should consist.
Whereas, in diseased states characterized by slow progress and ab sence of fever the digestive powers may he considered almost normal, excepting when accompanied by gastro-intestinal complications (e.g., tuberculosis); in other conditions, particularly the fevers, the function of the gastro-intestinal tract is probably faulty from lack of glandular action. Practically everything depends upon the functionating power of the gastro-intestinal tract; this manifests itself with greater or less certainty through the condition of the appetite.
The appetite as such, as well as its variations, represents an instinc tive guide, which, like so many other instincts, has a deep physiological meaning, although it may fail under certain abnormal conditions, or if improper food is used. Frequently enough, however, it remains correct even when opposed to theory (particularly of a chemico-physiological character), from which we must infer that there is a relationship between appetite and the needs of the Daly for food. From the investigations of Pawlow, we know that the appetite, as such, lip to a certain degree insures digestion by stimulating the secretion of gastric juice, the gas tric digestion in turn starting intestinal digestion. Only very few sub
stances have a similar power without the assistance of the appetite, e.g., milk and broths, We can, then, virtually ignore the appetite only when it is a question of supplying fluids containing sugar, salts, acids, etc., while it is hardly possible to dispense with a supply of nourishment which must first be digested in the stomach. The most natural stimu lus to the taking of nourishment is healthy hunger, which, in many dis eased conditions, especially those accompanied by fever, is waited for in vain, ill spite of au empty stomach, reappearing only with the begin ning of convalescence. Loss of appetite due to constipation, a frequent enemy, is the most readily removed.
Where the appetite has failed, there are many ways of stimulating and increasing it, the knowledge of which is of great practical importance. Above all, it is necessary to prepare the food properly and offer it in such variety and at such intervals that it will be taken with relish. Appetizing, stimulating, and nourishing foods should be used, and should be combined with due regard for the individual taste, and for the vaga ries of appetite prompted by illness. In this way, it is often possible to give more nourishment than when the diet is arranged upon a purely theoretical basis.without taking the patient's tastes into consideration. The well known influence of the mental state upon digestion should be remembered, and an effort be made to awaken cheerful thoughts during the meal, as mental depression from pain, mourning, and particularly from homesickness, hinders it. It is often possible, in the nursery or at the sick bed, to arouse the appetite by a variety of methods; sometimes severe disciplinary measures lead to a quicker and better result than can be obtained by other means. Finally, the use of drugs for improving the appetite is invaluable. As we will explain below, the body weight can be favorably influenced by improving the appetite without changing the diet in any respect.
How the normal child should be fed at the various periods of its life will be considered in another place. The nourishment of the sick child should approximate as closely as possible to that of the healthy one. This is least feasible in the acute febrile diseases, as the food must be greatly diluted and ntacerated so that the digestive juices may act upon it readily. Vegetables rich in cellulose, meat rich in fats and con nective tissue, and fats in solid or liquid form, are to he avoided. Aside from the particular indications for this nourishment in diseases of the intestines (e.g., typhoid fever), it is also of value in prolonged febrile. conditions, in which, if the fever is absent for hours or days, these pe riods free from fever may be utilized for the administration of stronger nourishment and perhaps of solid food. Moreover, in that most fre quent di.sease of childhood, scrofulo-tuberculosis, if the temperature is carefully taken for periods of weeks and months it will very often be found that the maximum temperature for the day lies at the upper limit of the normal, or it may be suhfebrile. A fall in the temperature in such a ease will be accompanied by an increase in appetite. It may perhaps be chronic intoxication from the poison of tuberculosis which, in the various forms of scrofulo-tuberculosis and outspoken tuber culosis, lowers the appetite or renders it capricious. Here it is necessary to stimulate the appetite by the use of drugs and by the particular kind of food suitable for the purpose, the consistency and composition of the food not being too unlike that required by a normal child. Of all foods, milk whether raw, pasteurized, or boiled, holds a most important place in febrile diseases, especially as it can be digested in the absence of appe tite, owing to its fluid form and its composition. and because it can be obtained in large quantities. In the absence of fever, however, milk should be withdrawn if it interferes too much with the administration of a normal mixed diet (which is to be desired), or if it leads to severe constipation; then cream, or, better still, butter, is to be preferred.