Induced Hypothermia for Infants With Hypoxic- Ischemic Encephalopathy Using a Servo-Controlled Fan: An Exploratory Pilot Study

Abstract

Servo-controlled fan cooling with room-temperature air, combined with servo-controlled radiant warming, was an effective, simple, and safe method of inducing and maintaining rectal temperatures of 33 degrees C to 34 degrees C in sedated infants with hypoxic-ischemic encephalopathy. After induction of hypothermia, a low fan speed facilitated accurate temperature control, and warmer-controlled rewarming at 0.2 degrees C increments every 30 minutes resulted in more appropriate rewarming than when 0.5 degrees C increments every hour were used.

A Comparison of Cooling Methods Used in Therapeutic Hypothermia for Perinatal Asphyxia

“…29 Recently described is a custom-made servo-controlled fan used in conjunction with a servo-controlled radiant warmer. 10 Three fans that normally are used to cool desktop computers direct room temperature air cephalocaudally over the infant. They achieved a mean Trec of 33.6°C with an SD of 0.1 to 0.2°C in a pilot study of 10 infants.…”

“…Although the principles of cooling infants remain the same, the method of cooling has differed greatly both within and outside the trial setting. [1][2][3][4][5][6][7][8][9][10] Since these trials have been completed, newer technologies that are currently in clinical use have emerged, yet many questions regarding the differences between the methods that are being used remain to be answered. The CoolCap trial used a water-filled cap (Olympic Medical Cool Care System [Olympic Medical, Seattle, WA]) applied to the infant's head to induce selective head cooling combined with radiant heating while maintaining core temperature at 34.5°C.…”

Neuroprotection and Hypothermia in Infants and Children

“…Furthermore, insulin sensitivity can increase during rewarming, leading to hypoglycemia, if the patient has been treated with insulin. Finally, experimental and clinical data show that rapid rewarming may produce loss of the protective effects of TH [49,54,55].…”

“…When rewarming speeds are high it is possible to detect a relapse of the destructive cellular processes [49,54]. A slower servo-controlled rewarming (0.2°C vs 0.5°C increments every 30 minutes) has been found to be more appropriate in term neonates with HIE [55].…”

Consenso sobre manejo integral del neonato con encefalopatía hipóxico isquémica

“…Deben ser utilizados dispositivos de hipotermia moderada, equipados con una manta base de temperatura servocontrolada. Están descritos otros dispositivos, tales como botellas de agua 21,22 , ventilador de aire 23 , bolsas de gel refrigerado 6 .…”