The Precision Between Transcutaneous Carbon Dioxide Versus PaCO2 in Infants Undergoing Therapeutic Hypothermia

BACKGROUND

Infants with hypoxic-ischemic encephalopathy are often treated with therapeutic hypothermia and high-frequency ventilation. Fluctuations in PaCO2 during therapeutic hypothermia are associated with poor neurodevelopmental outcomes. Transcutaneous CO2 monitors offer a noninvasive estimate of PaCO2 represented by transcutaneously measured partial pressure of carbon dioxide (PtcCO2 ). We aimed to assess the precision between PtcCO2 and PaCO2 values in neonates undergoing therapeutic hypothermia.

METHODS

This was a retrospective chart review of 10 neonates who underwent therapeutic hypothermia requiring respiratory support over 2 y. A range of 2-27 simultaneous PtcCO2 and PaCO2 pairs of measurements per neonate were analyzed via linear mixed models and a Bland-Altman plot for multiple observations per neonate.

RESULTS

A linear mixed-effect model demonstrated that PtcCO2 and PaCO2 (controlling for sex) were similar. The 95% CI of the mean difference ranged from -2.3 to 5.7 mm Hg (P = .41). However, precision was poor as the PtcCO2 ranged from > 18 mm Hg to < 13 mm Hg than PaCO2 values for 95% of observations.

CONCLUSIONS

The neonates' PtcCO2 was as much as 18 mm Hg higher to 13 mm Hg lower than the PaCO2 95% of the time. Transcutaneous CO2 monitoring may not be a good trending tool, nor is it appropriate for estimating PaCO2 in patients undergoing therapeutic hypothermia.

Neonatal outcomes of non-vigorous neonates with meconium-stained amniotic fluid before and after change in tracheal suctioning recommendation

OBJECTIVE

To evaluate the short-term outcomes of non-vigorous infants born through meconium-stained amniotic fluid (MSAF) before and after implementation of no-tracheal suctioning guidelines.

STUDY DESIGN

Single-center retrospective study of ≥36-week gestation neonates with MSAF.

RESULTS

During routine-suction era (9/2013-12/2014), 280/2306 neonates (12%) were born through MSAF and 39 (14%) were non-vigorous. Thirty (77%) of non-vigorous infants underwent tracheal suctioning. In the no-suction era (1/2017-12/2018), 282/2918 neonates (9.7%) were born through MSAF and 30 (10.6%) were non-vigorous and one needed intubation. Admissions for meconium aspiration syndrome (15% vs 53%) and respiratory distress (18% vs 57%) were significantly higher among non-vigorous infants in the no-suction era.

CONCLUSIONS

In this single-center study, non-vigorous infants born through MSAF without routine-tracheal suctioning had a higher incidence of NICU admission for MAS and respiratory distress compared to the routine-suction era. Multicenter randomized trials evaluating tracheal suction in non-vigorous infants with MSAF are warranted.