NORMAL PEOCESSES OF ENERGY METABOLISM 631 



TABLE 26 

 RESPIRATORY QUOTIENTS THE FIRST EIGHT DAYS (Benedict and Talbot) 



is resorted to, the modern infant is doomed to almost complete starvation 

 for the first three days, although it is clear, even from the average R. Q. 

 in the observations made at Boston, that glycogen is present in sufficient 

 quantity to prevent starvation acidosis the first day. When milk comes 

 in sufficient quantity on the fourth day, the average respiratory quotient 

 responds noticeably and on the fifth and sixth days mounts to a level 

 which indicates a satisfactory state of nutrition. 



The question has often arisen whether the newboni infant is capable 

 at once of digesting and metabolizing a sufficient quantity of breast milk 

 even if it were present, to prevent loss of weight. The answer to this 

 question must be sought by means of the respiration apparatus. The mat- 

 ter will be discussed in its quantitative aspects at greater length beyond. 

 Meantime, it may be noted that Hasselbalch has tested the capacity of 

 the newborn to absorb and metabolize grape and milk sugar and that per- 

 fectly satisfactory evidence was obtained from the respiratory quotient 

 that this capacity is developed by the end of the second day. 



Infants born prematurely may have a high R. Q. within the first few 

 hours after birth but by the fifteenth hour the supply of glycogen, or the 

 hyperglycsemia due to labor or anesthesia or both, has been considerably 

 reduced and the child may be already on a nearly pure fat metabolism. 

 When an adult mammal already well nourished is giver even a small quan- 

 tity of an easily absorbed sugar, the effect upon the R. Q. may be seen 

 within the first half hour. When, on the other hand, fat is given in large 

 amount, the effect upon the quotient may not be seen until the third to 

 sixth hour. We may expect then that in feeding an infant with milk, 

 whether mother's or cow's milk, it is the sugar of milk which is burned 

 first and the fat will only be absorbed in sufficient quantity to affect the 

 R. Q. after several hours. 



The work of Hasselbalch demonstrates these points very clearly. After 

 feeding infants 2 and 4 days of age with breast milk, he found the high- 

 est quotient (.92 and .93) l 1 /^ hours after the meal. In one case he was 

 able to show that an experiment begun 2 hours after a feeding gave a 

 quotient 4 points lower than an immediately succeeding period begun only 

 one hour after a similar -feeding. Apparently in Hasselbalch's experi- 

 ments, as in those of Bailey and Murlin, it is much easier to secure this 

 rise of quotient with infants five days or more of age than it is with 

 those of 2 days or less. The explanation clearly is that unless artificial 



