104 



PHYSIOLOGY OF THE NEW-BORN INFANT. 



day. In an attempt to study the heat-production more closely, the 

 chart has been so plotted as to show the values obtained on each half 

 day. We find but little difference between the first and last halves of 

 the first day, however, as the number of observations in the second 12 

 hours of life were relatively few. As a matter of fact, all values below 

 520 calories per square meter of body-surface were obtained inside of 

 the first 12 hours of life. 



From figures 7, 8, and 9, therefore, it is evident that in our problem 

 of studying the metabolism of infants during the first week of post- 

 natal life we have two distinct phases to consider: (1) the metabolism 

 on the first day of birth, and (2) the metabolism on the remaining 5 or 

 6 days of the first week. While all of the charts thus far studied 



Calories per Kilo, per 24 Hours 



FIG. 8. Minimum heat-production of new-born infants per kilogram of 

 body-weight per 24 hours referred to age. 



indicate clearly that there is no approximation to uniformity shown 

 in the metabolism of new-born infants during the first week of life, the 

 analysis just made shows that a large part, if not indeed the greater 

 part, of the extreme values found in our observations may be attributed 

 to the measurements obtained during the first 24 hours of life. Hence 

 our general conclusion with regard to the metabolism of new-born 

 infants holds true, particularly for the first day of life, namely, that 

 there is no relationship between the total metabolism and either the 

 body-weight or the body-surface. We have to consider, therefore, if, 

 after eliminating the first day of post-natal life, in which there is 

 admittedly a profound physiological readjustment inside the organism, 

 any tendency towards uniformity may be noted in the remaining days 

 of the week. 



