Abstract

AIM To determine ranges for skin temperatures in infants weighing under 1000 g in the first five days of life.

METHOD Abdominal skin and foot temperatures were automatically collected each second, averaged over 1 minute and stored on computer. A computer program analysed the data in 83 babies weighing under 1000 g at birth over the first five days of life and expressed the temperatures as means and standard deviation. The temperature patterns seen in these babies were also visually analysed. The relation between an increasing abdominal skin-foot temperature difference and other signs of hypovolaemia was also studied.

RESULTS These babies all had similar temperature patterns. Just after birth there was little ability to vasoconstrict in the presence of cold stress and the babies behaved more like poikilothermic animals. Vasomotor tone developed in the first three days, resulting in a stabilisation of the abdominal skin temperature to a mean of 36.9⁰C and a widening of the central-peripheral temperature difference (Td) to a mean of 1.0⁰ C. A Td of > 2⁰ C was associated with other evidence of hypovolaemia for only 11% of the time.

CONCLUSIONS Infants weighing under 1000 g have poor vasomotor control at birth and are at increased risk from cold stress. After the first two to three days of life, monitoring the central-peripheral temperature difference gives an early indication of cold stress.