Temperature changes during neonatal surgery.

My subject is temperature changes occurring during neonatal surgery. My interest in this subject was stimulated by the obvious cooling which occurred during neonatal operations, the absence in current practice at Great Ormond Street of any special measures to prevent this loss, and the varied methods of rewarming in practice. Also there occurred one or two cases of post-operative sclerema, and it seemed worth while to investigate this temperature loss more fully. In the past six months or so I have recorded the temperatures, at 10-minute intervals, of 25 infants during operation. Temperatures have been recorded in all cases by a Thermocouple calibrated against an alcohol thermometer reading over the range 20-40° C. and the lead has in all cases been placed in the rectum, except on the two occasions when this would have interfered with the operation. An oesophageal lead was then used. The oesophageal temperature has usually been found, on the occasions when both readings have been taken, to be somewhat higher than the rectal, but the same rate of drop has occurred. The infants are divided into two groups: in the first 14 the existing practice was followed, no measures being taken to prevent heat loss, and in the next 11 cases the limbs and trunk, apart from the operation site, were insulated with cotton wool held in position by crepe bandages. On later analysis of the type of operations performed it was found that these two groups could fairly be compared. The average time of operation was 80 minutes and the average temperature loss in the control group was 2 310 C. and in the insulated group 1 56° C. (Table 1). The following are some graphic records of these infants, all of whom were less than 7 days old. In the control group the greatest loss recorded was in a 6-day-old infant with a diaphragmatic