Perioperative hypothermia in neonatal intensive care unit patients: effectiveness of a thermoregulation intervention and associated risk factors

Background: Hypothermia in neonatal intensive care unit patients is associated with morbidity. Perioperative normothermia is the standard of care. Aims: We hypothesized that a quality improvement intervention (transport protocol, transport education, ongoing monitoring) would decrease the incidence of perioperative hypothermia. Secondarily, we hypothesized that patients undergoing surgery at a postmenstrual age of <37 weeks or at a weight of <1.5 kg would be at higher risk for perioperative hypothermia. Methods: Lean Six Sigma methodology was used to institute a quality improvement intervention. In a retrospective chart review, we identified 708 cases for which the neonatal intensive care unit was the preoperative and postoperative destination and documented patient characteristics, including postoperative temperature. Cardiac surgical cases and cases with no postoperative temperature record were excluded. Results: Patients in the postintervention group had a statistically significant decrease in hypothermia compared to those in the preintervention group (P < 0.001; OR: 0.17; 95% CI: 0.09–0.31). The absolute risk of hypothermia was 23% in the preintervention group and 6% in the postintervention group. Weight <1.5 kg on day of surgery (P = 0.45; OR: 0.63; 95% CI: 0.16–2.24) and postmenstrual age (P = 0.91; OR: 1.07; 95% CI: 0.33–3.98) were not risk factors. Odds of hypothermia were increased in patients undergoing interventional cardiology procedures (P = 0.003; OR: 17.77; 95% CI: 2.07–125.7). Conclusions: Perioperative hypothermia is a challenge in the care of neonatal intensive care unit patients; however, a thermoregulation intervention can decrease the incidence with sustained results. Future studies can examine why certain procedures have a tendency toward increased perioperative hypothermia, determine the relative value of quality improvement interventions, and characterize the morbidity and mortality associated with perioperative hypothermia in neonatal intensive care unit patients.