Transcutaneous carbon dioxide pattern and trend over time in preterm infants.

BACKGROUND: Chronic lung disease remains a burden for extremely preterm infants. The changes in ventilation over time and optimal ventilatory management remains unknown. Newer, non-invasive technologies provide insight into these patterns. METHODS: This single-center prospective cohort study enrolled infants ≤32 0/7 weeks. We obtained epochs of transcutaneous carbon dioxide (TcCO2) measurements twice each week to describe the pattern of hypercarbia throughout their hospitalization. RESULTS: Patterns of hypercarbia varied based on birth gestational age and post-menstrual age (PMA) (p = 0.03), regardless of respiratory support. Infants receiving the most respiratory support had values 16-21 mmHg higher than those on room air (p < 0.001). Infants born at the youngest gestational ages had the greatest total change but the rate of change was slower (p = 0.049) compared to infants born at later gestational ages. All infants had TcCO2 values stabilize by 31-33 weeks PMA, when values were not significantly different compared to discharge. No rebound was observed when infants weaned off invasive support. CONCLUSIONS: Hypercarbia improves as infants approached 31-33 weeks PMA. Hypercarbia was the highest in the most immature infants and improved with age and growth despite weaning respiratory support. IMPACT: This study describes the evolution of hypercarbia as very preterm infants grow and develop. The pattern of ventilation is significantly different depending on the gestational age at birth and post-menstrual age. Average transcutaneous carbon dioxide (TCO2) decreased over time as infants became more mature despite weaning respiratory support. This improvement was most significant in infants born at the lowest gestational ages.

Intraventricular Hemorrhage and Patent Ductus Arteriosus Ligation Association with Infant Mortality.

BACKGROUND: Practice patterns for the management of patent ductus arteriosus (PDA) in premature infants are changing with advances in medical management. We sought to determine the increased mortality for premature infants who had a PDA ligation with a co-existing diagnosis of intraventricular hemorrhage (IVH). METHODS: Premature neonates (<1 y old with known gestational week ≤36 wk) with a diagnosis of IVH were identified within the Kids' Inpatient Database (KID) for the years 2006, 2009, and 2012. Diagnoses and procedures were analyzed by ICD-9 codes and stratified by a diagnosis of PDA and procedure of ligation. Case weighting was used to make national estimations. Multivariable logistic regression was performed to adjust for confounders. RESULTS: We identified 7567 hospitalizations for premature neonates undergoing PDA ligation. The population was predominately male (51.6%), non-Hispanic white (41.1%), were from the lowest income quartile (33.1%), had a gestational week of 25-26 wk (34.0%), and a birthweight between 500 and 749 g (37.3%). There was an increased mortality (10.7% versus 6.3%, P < 0.01) and an increased length of stay (88.2 d versus 74.4 d, P < 0.01) in those with any diagnosis of IVH compared with those without. Adjusted multivariable logistic regression demonstrated that high-grade IVH (III or IV) was associated with a significantly increased risk of mortality in those undergoing PDA ligation (aOR 2.59, P < 0.01). Specifically, grade III and IV were associated with an increased odds of in-hospital mortality (aOR 1.99 and 3.16, respectively, P < 0.01). CONCLUSIONS: Attitudes regarding the need for surgical intervention for PDA have shifted in recent years. This study highlights that premature neonates with grade III or IV IVH are at significantly increased risk of mortality if undergoing PDA ligation during the same hospitalization. LEVEL OF EVIDENCE: III.