Keeping the incubator very warm increases the loss of hemoglobin. Indigestion increases the anemia. The anemia increases as the stay in the incubator is prolonged. The administration of iron can only partially diminish the loss of iron. It is clear, then, to treat this anemia, in addition to the administration of iron, the infant should be removed from the incubator as soon as possible.
Premature infants show a remarkable predisposition to the appearance of edema.
It occurs especially in connection with anemia, but it may appear in those whose blood shows little diminution in hemoglobin. Indigestion and malnutrition favor its appearance in a marked degree. One observation made, appears to correlate very forcibly the fact established by Widal, etc., that an excess of sodium chloride in the blood favors the retention of serum in the tissues. In two cases, in which on account of an irritable stomach an insufficient supply of food was given and a 1 per cent solution of sodium chlorid was administered by the mouth and rectum, edema in a severe degree appeared. This disappeared promptly on the withdrawal of the salt.