The Reaction of the Child's Organism upon the short survey we have just given of the commonest sources of infec tion and of their usual habitat we readily understand how easily they may enter into the cellular structure of the body. Small breaks in the skin, as the hair follicles, suffice for their entrance; disturbances in the mucous membrane or thermic or mechanical irritation (refrigeration) reduce the resistance of the mucous membrane sufficiently to permit the transmigration of micro-organisms.
The mucous membranes on which they usually live have adapted themselves to their lodgers, and their plentiful blood-supply is without doubt an added means of protection, which is further aided by the secre tion of mucus. Granulating wounds are also protected against bacterial invasion so long as they remain uninjured (NOtzel). Scratching and sloughing disturb the protective layer.
When the bacteria have once entered through a breach in the tis sues then will follow that fight which we call inflammation, from the close observation of which Bier has evolved his ingenious method of treatment. We must never forget when we are treating an infectious process that the inflammation is nature's attempt at walling it in, that the fever is an indication of the fight, and that we are, as a rule, not justified in interfering except when specially indicated We possess an excellent means of watching the general condition of the system in the temperature curve. Especially in the child's body
will we observe that the reaction is a considerable one and may easily make us apprehensive; on the other hand, we must always remember that the child's heart is still sound and only rarely affected by chronic poisoning and that it will therefore usually surmount severe suppura tions easier than the adult (purulent peritonitis, multiple suppuration of joints in infants). We must, however, guard against any extensive trauma and profound shock, as these may suddenly reduce the life energy to its lowest ebb, owing to the ever-present danger of the lym phatic diathesis.
Thus we will observe that children do not stand relatively large wounds well, extensive opening of infected cavities filled with purulent exudate (pleurisy, peritonitis), nor a long-continued narcosis which might be required for the surgical measure.
Neither do children, especially small ones, stand considerable loss of liquid, be it blood or exudates of any considerable amount; they dry up, as we may say, under the hands of the physician (see Empyema).