Delivery room oxygen physiology and respiratory interventions for newborns with cyanotic congenital heart disease. Thomas AR, Ma AL, Weinberg DD, Huber M, Ades A, Rychik J, Foglia EE. J Perinatol. 2021 Mar 23. doi: 10.1038/s41372-021-01029-2. PMID: 33758390
Take-Home Points:
- In a single-center retrospective study of neonates born with cyanotic congenital heart disease, a comparison was made of the trends of oxygen saturations for the first ten minutes after birth between three physiologies – single ventricle physiology with critical aortic obstruction, single or double ventricle physiology with pulmonary outflow obstruction, and those with transposition of great arteries physiology (TGA)
- Infants with TGA physiology had lower pulse oximetry levels at all recorded time points (up to 10 min) when compared to those with ductal dependent systemic and pulmonary circulation.
- Infants with TGA physiology received supplemental oxygen therapy and respiratory interventions more frequently than the other groups.
- Majority of the infants had stable cardiovascular status with initially recorded heart rates of more than 100 beats per minute.
Commentary from Dr. Venu Amula (Salt Lake City, UT, USA), section editor of Pediatric & Fetal Cardiology Journal Watch: Newborns with cyanotic congenital heart disease differ from normal neonates concerning oxygen saturations(SpO2). Their transition from fetal to neonatal physiology at birth is also different, and reference oxygen saturation trajectories and respiratory interventions needed have not been well established.
In this study by AR Thomas et al., the authors characterize and trend SpO2 values at birth in neonates with cyanotic congenital heart disease. They also report the frequency and intensity of delivery room respiratory interventions in neonates during the birth transition. This single-center, retrospective study of all infants born at > or = 32 weeks GA with a prenatal diagnosis of cyanotic congenital heart disease at a quaternary pediatric care center with a Level IV neonatal care nursery. Based on fetal echocardiogram – the infants were grouped into three categories – those with single ventricle physiology with critical aortic obstruction (SV-CAO )leading to ductal dependent systemic circulation, those with critical pulmonary outflow obstruction ( CPO) with either single ventricle or two ventricles but ductal dependent pulmonary flow and the third group with transposition physiology (TGA) where the systemic and pulmonary circulations are in parallel.
At birth for all infants, the standardized institution neonatal resuscitation guidelines were followed with anticipated goal saturations of 75-85% for neonates given their cyanotic heart lesion. The saturations were measured on the right hand to obtain preductal measurements. Interventions were indicated to maintain saturations in the goal range and provide supplemental oxygen therapy, continuous positive airway pressure, positive pressure ventilation, and endotracheal intubation.
Delivery room interventions and minute-to-minute SpO2 values were compared across and between three diagnostic groups using standard statistical tests. Of 208 infants ≥32 weeks gestation with eligible prenatally diagnosed cardiac lesions born during the study period, 196 infants were included in the analyses of oxygen saturation and respiratory intervention data. The TGA group had lower pulse SpO2 values at each time point. Comparing each group separately to TGA showed significant differences in SpO2 values at each minute (all p < 0.01 for CPO v TGA and all p < 0.02 for SV-CAO v TGA). No significant differences were found in pairwise comparison of the SV-CAO group to CPO group (p > 0.05) in SpO2 values at each minute after birth. Infants with TGA physiology received supplemental oxygen and non-invasive respiratory interventions more frequently than the infants in the SV-CAO and the CPO groups (Table 3). Significantly more infants with TGA physiology underwent endotracheal intubation in the resuscitation suite (53%) and occurred at a median of 24 (IQR 18–35) minutes after birth.
This study attempts to analyze the trends of target oxygen saturation in children with cyanotic congenital heart disease immediately after birth. These infants represent a heterogeneous group of neonates, and even within the same physiology group, the spectrum of disease dictates the target oxygen saturation achieved. The interventions were performed to achieve the goal target oxygen saturations of 75-85% – and represent the current practice in most institutions, although the optimal saturations are not well known. The goal is to accept some degree of hypoxia to maintain adequate systemic perfusion. Though the study represents a single-center practice, this information is valuable to guide physicians in providing resuscitation to babies with known cyanotic heart disease.
Smoothed conditional curves of the 25th, 50th, and 75th percentiles for pre-ductal SpO2 values for minutes 3–10 after birth were plotted for each diagnostic group and for comparison, the 25th, 50th, and 75th percentile values for SpO2 at each minute reported for infants without CCHD by Dawson et al.(1)
- Dawson JA, Kamlin COF, Vento M, Wong C, Cole TJ, Donath SM, et al. Defining the reference range for oxygen saturation for infants after birth. Pediatrics. 2010;125:e1340–7.
