In the preceding section have been indicated briefly some of the principal causes of disease and the methods for their investigation or removal. We have now to consider some of the practical applications which may be made of the laws of etiology and prevention of disease in the treatment of the sick. While the removal of the cause of illness by no means always effects a cure, yet the importance of a knowledge of this cause as an aid to diagnosis, prognosis, and therapeutics is so evident as to require no proof.
To discuss with anything like completeness the practical applications of what would be commonly considered as hygienic rules in the treatment of disease would be to write a treatise on nursing, and would also include a large part of the practice of medicine, for regimen is the more important half of practical therapeutics. The hygienic requirements peculiar to each disease will be pointed out by the writers upon special subjects, and I shall only venture upon one or two general remarks in addition to the hints already given in speaking of the several causes.
In the acute stages of disease the sensations—or, if the term be preferred, the instincts—of the patient are usually the best guide to his regimen so far as they go. In most cases he desires quiet, shade, but not absolute darkness, and little or no food, although there is often a craving for drinks, especially of a cooling character. In the specific fevers which have a tolerably definite period and course it is important to keep up the nourishment even during the period of anorexia, in order to provide against the debility which is to follow. This nourishment is best given in the form of drink, and very frequently fresh milk is the type of what is required. The old notion that whatever a sick man desired must be hurtful, and therefore that the fever patient must be kept hot and refused cool water, has now almost entirely passed away.
In convalescence from acute disease and in many chronic cases, the sensations of the patient are not to be trusted as a guide in the choice of food. In such diseases as yellow fever and typhoid fever to allow the convalescent to follow the dictates of his appetite is to run great risk of a fatal result. In other cases the patient really has no wish in the matter, but it will often be found that one who can think of nothing which he desires to eat, and who will even refuse a dish which he has requested and been thinking about, will eat with enjoyment some unexpected dainty when presented at the right moment and properly served as a skilled nurse knows how to do. The manner of serving the food, independent of its cooking, is not a matter of such small importance that the physician can afford to overlook it, and he will succeed best as a practitioner who best appreciates the influence which cracked goblet, a chipped saucer, a soiled napkin, or, on the other hand, a hot plate or a touch of color in the shape of a leaf or flower, may have upon the capricious appetite of the sick. In ordering diet for convalescence it is not an uncommon error to select only those articles which are agreeable to the physician himself, forgetting the old proverb, that what is one man's meat may be another man's poison, and also that it is above all things desirable to avoid monotony. One doctor always orders chicken, another eggs, a third a mutton-chop, etc. The practice in this respect has probably been unduly influenced by the reports of Beaumont of the results of his observations on Alexis St. Martin, and we still find that the relative digestibility of various articles of food is estimated according to the scale laid down in these reports, with no allowance for individual peculiarities, previous habits, mode of cooking, etc. The secret of success in the diet of convalescence lies mainly in the simplicity of the individual dishes, in varying the different meals, in the manner of serving, and in carefully observing the effects on the sick person, and being guided by the results.
To promote appetite and digestion, and to secure refreshing sleep, one of the most important things is fresh air, but in many houses a sick person will obtain but a very limited allowance of this if the physician does not give special attention to the matter. Except in cases of contagious disease, the rules for managing which have been given in a previous section ([p. 201]), as soon as a patient is sufficiently recovered to be moved for a short time into another room his bedroom should be thoroughly aired and cleansed, and this should be done morning and evening thereafter.
In treating cases of contagious disease the question often arises as to means of individual prophylaxis to be used by those who must be exposed to the effects of the infected locality or of the presence of the sick. The attempts which have been made to secure this individual protection in the midst of an epidemic have been numerous and varied, ranging from the use of the "vinegar of the four thieves" of the Middle Ages to the employment of the sulphites and chlorates to make the blood unsuited to the growth and multiplication of the supposed germs, or of cotton-wool respirators to strain the infected air, or of supposed specifics for particular diseases, as belladonna for scarlet fever and vaccination against small-pox. As yet, there is little or no satisfactory evidence as to the value of individual precautions against those diseases whose contagion is conveyed through the air, small-pox alone excepted, but in case of diphtheria in one member of a family of children it might be well to try the use of chlorate of potash internally, combined with the local application of the tincture of the chloride of iron, as suggested by E. M. Hunt. The question is one to be investigated by careful observation and experiment; and, though it is improbable that any definite results will be obtained except in those diseases which are communicable to animals, and therefore susceptible of direct experiment, still, it is possible that some advance may be made. In rare and exceptional cases—as, for instance, in exploring a crowded, filthy, and intensely infected typhus-fever nest, as a tenement-house, or an infected yellow-fever ship—it may be worth while for the physician or inspector who is unprotected by a previous attack of these diseases to make use of a cotton-wool respirator, which is readily extemporized, and belongs to that exceedingly valuable and popular class of remedies which, "if they do no good, can do no harm." In epidemics of typhus, cholera, or yellow fever one of the most valuable prophylactics is to have a mind so occupied with other matters that it pays little or no attention to the danger, while in case of small-pox fear of the disease is indirectly the best prophylactic, since it leads to careful vaccination.
This branch of the subject is closed with the remark that it would be well if physicians, and especially the younger ones, gave more attention to the preservation of their own health than many of them do. The possession of a medical diploma does not prevent the evil effects of irregular and hurried meals, insufficient sleep, exposure to inclement weather, and lack of systematic and sufficient exercise; and too much tobacco, sometimes too much alcohol, and in exceptional cases too much study and literary work, so often combine with anxiety about individual patients or with pecuniary worries to damage the digestion and nervous system of the young practitioner that the wonder is that so many survive the ordeal. And, in fact, the mortality among physicians under the age of thirty is higher than that of any other profession during the same period of life.
III. Public Hygiene in its Relations to Physicians.
An important difference between man and animals is found in the extent to which he will sacrifice a present pleasure or convenience to secure a future good or to avoid a future evil. The savage will do this to only a very limited extent—little more, in fact, than the beaver or the squirrel—and the lesson is learned but slowly and by sad experience. This is especially the case as regards matters affecting health. When a man begins to take special precautions as to his diet or exercise, having in view rather his future health than his present comfort and tastes, he has in most cases already begun to suffer from the effects of his imprudence, and does not commence a hygienic course of life as a perfectly sound and healthy person. The same is true for a community. It will not usually submit to the burden of taxation necessary to secure drains and sewers or a proper registration of vital statistics, nor to the cost and inconvenience of the machinery necessary to limit the spread of contagious diseases, until the neglect of these things has resulted in such an amount of disease and death as to forcibly call attention to the matter. The result is, that the burden is far heavier than it would have been had the work been undertaken in proper season, and individuals may find it to their interest to leave the place and settle elsewhere rather than remain and meet their proportion of the expense.
When a state or municipality has so far advanced in civilization as to consider it desirable to take measures to protect the public health by preventing individuals from polluting the air or water liable to be used by their neighbors, etc., the services of the medical profession are always called upon. The foundation of public hygiene is information as to the occurrence of certain forms of disease, the cause of which can be referred with more or less precision to a certain limited locality. This information may be very imperfect, consisting of little more than rumor and opinions as to the existence of an undue amount of sickness or mortality in a certain place, or it may consist of precise reports setting forth the number of deaths from each cause, the proportion of each of these to the population by age, sex, occupation, etc., and of the whole to births—constituting what is commonly called the "vital statistics of a place"—and also of reports of the occurrence of certain preventable diseases; and between these two the information may be of various degrees of completeness, but, whatever there be, it is for the most part obtained either directly or indirectly from medical men. The reliability and completeness of the information thus obtained by the state determines to a great extent the direction and character of the work done in destroying or preventing the causes of disease, and it is also an important means of increasing our knowledge with regard to the nature of these causes.