Abstract 1345 Neonatology: Clinical Investigation Platform, Monday, 5/3

There are no data available on the optimal skin temperature set point for the full term infant cared for under a radiant warmer. These infants are occasionally observed to become hyperthermic when their skin temperature is servo-controlled at ≥ 36.5° C.

Objective: The purpose of this study was to determine the optimal skin temperature set point for full term infants kept under radiant warmers.

Method: 13 stable full term infants (GA 40 wks, BW 3319g, postnatal age 48.3 hrs) were studied after feedings and during normal sleep. They were placed in the supine position under a radiant warmer with proportional heater output (Air-Shields Health Dyne Company, Hatboro Penn Model RM 78-1) only dressed with a diaper. Skin temperature measured in the upper left abdomen with a thermistor covered with a heat reflecting patch, was servo-controlled at 36.5, 36.0 or 35.5° C in random sequence for 1.5 to 2.0 hrs each. Oxygen consumption (V′ O2), and CO2 production (V′CO2) were measured with an open flow system. Ambient, skin, axillary, peripheral (right big toe) and rectal temperatures were recorded with thermistors for at least one hour after all temperatures had stabilized following each change in set point. (Table) As expected by study design, skin T was significantly different between the three set points. Peripheral T also increased with increases in set point. However, rectal T did not change significantly and stayed within the normal range. Metabolic rate was lowest at 36.5° C and increased significantly at 35.5° C. No hyperthermia developed in any of the infants.

Table 1 No caption available
Full size table

Conclusion: Radiant warmers provide a thermoneutral environment for full term infants who are servo-controlled at skin temperatures between 36.0° C and 36.5° C.