Extremely Low Birth Weight Preterm Infants Lack Vasomotor Response in Relationship to Cold Body Temperatures at Birth

OBJECTIVE: This study evaluated peripheral vasoconstriction in ELBW infants when body temperature decreased during the first 12-hours of life. DESIGN: An exploratory, within-subjects design with 10 ELBW infants. Abdominal and foot temperatures were measured every minute. Peripheral vasoconstriction (abdominal > peripheral temperature by 2° C) and abdominal-peripheral temperature difference were also evaluated. RESULTS: Abdominal and peripheral temperatures were significantly correlated within each infant. One 880 g infant exhibited isolated peripheral vasoconstriction; a 960 g infant had abdominal temperatures more than 1° C higher than peripheral temperatures. Eight smaller infants exhibited no peripheral vasoconstriction and spent most of their observations with peripheral greater than abdominal temperatures. In 8 infants, mean temperature difference was significantly higher when abdominal temperature was less than 36.5° C. CONCLUSION: Most ELBW infants did not exhibit peripheral vasoconstriction during their first 12-hours of life, despite low temperatures. ELBW infants’ vasomotor control may be immature during this period.