Improved survival at the cost of more chronic lung disease? Current management and outcomes in extremely preterm infants born in New South Wales and the Australian Capital Territory: 2010-2020.

BACKGROUND: Since 2010, most tertiary care hospitals in Australia have changed how they care for extremely premature infants. However, in-hospital and longer-term outcome data have suggested unchanged or even worse health outcomes in later epochs, especially respiratory outcomes. This study examined the trend in outcomes since these changes were introduced, particularly the prevalence of chronic neonatal lung disease (CLD). METHODS: This is a retrospective cross-sectional analysis of data from the Neonatal Intensive Care Units' (NICUS) database of all perinatal intensive care units in New South Wales and the Australian Capital Territory, including infants born at ≥ 24 and ≤ 28 weeks of gestational age in tertiary perinatal units between January 1, 2010, and December 31, 2020. Temporal trends and changes in primary outcome were examined by linear and adjusted multivariable logistic regression models. RESULTS: This study included 3258 infants. We saw significant changes in antenatal magnesium sulfate (75% increase), delayed cord clamping (66% increase), delivery room intubations (30% decrease), any time (20% decrease), duration on mechanical ventilation (100-hour decrease), and hours on noninvasive ventilation (200-hour increase). Mortality decreased from 17% to 6%. The incidence of CLD increased significantly even when adjusted for confounders (15% increase). Any time and mean hours spent on mechanical ventilation significantly increased the odds of CLD. This study could not find a significant association of any of the protective antenatal treatments on CLD. CONCLUSIONS: The last decade saw a significant improvement in survival and survival to discharge without major morbidity. There was increased use of magnesium sulfate, delayed cord clamping, and less invasive respiratory management of extremely preterm infants. The avoidance of mechanical ventilation may impact the incidence of CLD.

Noninvasive assessment of the early transitional circulation in healthy term infants.

BACKGROUND: The early neonatal circulatory transition usually occurs smoothly but occasionally it is incomplete or reverts to the fetal state of high pulmonary vascular resistance, resulting in significant neonatal morbidity. OBJECTIVE: To define the normal values for echocardiographic parameters during the early transitional circulation in term infants. METHODS: Two-dimensional, M-mode, pulsed and color flow Doppler echocardiography was used to assess healthy term infants in the first 4 h of life. Left and right ventricular outputs (LVO and RVO) and myocardial performance indices (MPI), left ventricular fractional shortening, end-systolic diameter and end-diastolic diameter, ductal size, shunt and peak velocities, tricuspid regurgitation and left pulmonary artery diastolic velocities were documented. RESULTS: A total of 21 normal term infants were assessed with median gestation of 39 weeks, birth weight of 3,470 g and postnatal age of 3 h and 22 min. The median echocardiographic values were LVO 193 ml/kg/min, RVO 216 ml/kg/min, left MPI 0.41, right MPI 0.63, and fractional shortening 29%. The ductus was patent in all 21 infants with a median size of 2.3 mm; ductal flow was bidirectional in 86% with median peak left-to-right velocity of 1.07 m/s. The median left pulmonary artery diastolic velocity was 0.31 m/s and physiological tricuspid regurgitation was present in all infants. CONCLUSION: This study defines normal values for echocardiographic measurements in healthy term infants during the first 4 h after birth. These normative data may be useful in early identification of infants with abnormal circulatory transition, allowing more rapid determination of cardiovascular dysfunction.