Mild controlled hypothermia for necrotizing enterocolitis treatment to preterm neonates: low technology technique description and safety analysis

We performed a quality improvement project to necrotizing enterocolitis (NEC) and published our results about the initiative in 2021. However, aspects on the safety of the cooling and how to do therapeutic hypothermia with low technology to preterm infants are not described in this previous reporter. Thus, we aim to describe the steps and management to apply hypothermia in preterm infants using low technology and present the safety aspects regarding the initiative. We performed a quality improvement project to NEC in a reference hospital for neonatology (intensive care unit). Forty-three preterm infants with NEC (modified Bell's stage II/III) were included: 19 in the control group (2015-2018) and 24 in the hypothermic group (2018-2020). The control group received standard treatments. The hypothermia group received standard treatment and underwent passive cooling (35.5 degrees C, used for 48 h after NEC diagnosis). We reported cooling safety to NEC, assessing hematological and gasometrical parameters, coagulation disorders, clinical instability, and neurological disorders. We described how to perform cooling to preterm infants using incubators' servo-control and the occurrence and management of dysthermia during the cooling. We turn-off the incubator and used the esophageal probe to monitor the temperature every 15 min; if the temperature dropped, the incubator was turned on with a rewarming speed of 0.5 degrees C/h. The participants' average weights and gestational ages were 1186 g and 32 weeks, respectively. There were no differences among hematological indices, serum parameters (sodium, potassium, creatinine, lactate, and bicarbonate), pH, pCO2, and pO2/FiO2 between the groups during treatment and after rewarming. We did not observe dysthermia, bradycardia, hemodynamic instability, apnea, seizure, bleeding, peri-intraventricular hemorrhage, or any alterations in ventilatory parameters due to the cooling technique in preterm babies. This simple technique was performed without intercurrences through a rigorous team evaluation, with a target cooling speed of 0.5 degrees C/h. The target temperature was successfully reached between the second and third hours of life with the incubator control in 21 children; ice bags were used in only three cases. The temperature was maintained at the expected level during the programmed cooling period. Conclusion: Mild controlled hypothermia for preterm infants with NEC is safe. The cooling of preterm infants could be performed through passive methods, using the servo-control of the incubators for temperature management.

Automated summary

This study describes the steps and management of applying hypothermia in preterm infants using low technology and presents the safety aspects of the initiative. The results show that controlled hypothermia for preterm infants with NEC is safe when performed through passive methods with incubator servo-control for temperature management.