Comparison of Two Techniques of Superior Vena Cava Flow Measurement in Preterm Infants With Birth Weight <1,250 g in the Transitional Period-Prospective Observational Cohort Study

Objectives: Superior Vena Cava (SVC) flow in neonates measured by the standard approach has been validated by different groups around the world. The modified SVC flow measurement technique was recently suggested. The aim of our study was to evaluate standard and modified technique of echocardiography SVC flow measurement in a cohort of extremely preterm neonates in the immediate postnatal period. Methods: Prospective, observational cohort study in a level III neonatal center. Infants with birth weight <1,250 g were eligible for enrolment. SVC flow was measured by echocardiography using standard and modified methods at 6, 18 and 36 h of age. Our primary outcome was equivalency (using raw bounds of -20 to +20 mL/kg/min difference between the paired measurements), agreement and correlation between standard and modified methods of the SVC flow measurements. Results: Thirty-nine infants were enrolled. The mean gestational age of the cohort was 27.4 (SD 2.1) weeks of postmenstrual age, the mean birth weight was 0.95 kg (SD 0.2). The measurements at 6 and 36 h of age were equivalent as defined in the design of the study (p = 0.003 and p = 0.004 respectively; raw bounds -20 to +20 mL/kg/min). At 6 h of age the mean difference (bias) between the measurements was -0.8 mL/kg/min with 95% limits of agreement -65.0 to 63.4 mL/kg/min. At 18 h of age, the mean difference (bias) between the measurements was +9.5 mL/kg/min, with 95% limits of agreement -79.6 to 98.7 mL/kg/min. At 36 h of age the mean difference (bias) between the measurements was -2.2 mL/kg/min with 95% limits of agreement -73.4 to 69.1 mL/kg/min. There was a weak, but statistically significant correlation between the standard and modified method at 6 h of age (r = 0.39, p = 0.04). Conclusion: Both SVC flow echocardiography measurement techniques yielded clinically equivalent results, however due to wide limits of agreement and poor correlation they do not seem to be interchangeable.

Delivery room dextrose gel for preterm hypoglycaemia (the GEHPPI study): a randomised placebo-controlled trial

OBJECTIVE

Early hypoglycaemia at the time of neonatal intensive care unit (NICU) admission is common in very/extreme preterm infants. This study aimed to determine whether buccal dextrose gel in the delivery room (DR) would improve rates of early hypoglycaemia in this population.

DESIGN

Randomised, blinded, placebo-controlled trial.

SETTING

Four level-3 and one level-2 neonatal units.

PATIENTS

Inborn infants≤32+0 weeks gestational age (GA).

INTERVENTIONS

Infants were randomised to 40% dextrose or placebo gel in the DR (≤29+0 GA: 0.5 mL gel, ≥29+1 GA: 1 mL gel).

MAIN OUTCOME MEASURE

Hypoglycaemia (<1.8 mmol/L) measured at the time of first intravenous access at NICU admission.

RESULTS

Between November 2020 and August 2022, the recruitment rate was slow (impacted by the requirement for antenatal consent). This fact, coupled with finite research resources, led to a decision to end recruitment early. Data analysis of 169 newborns (33% of target sample size) showed no significant difference in the frequency of the primary outcome between dextrose 24/84 (29%) and placebo 25/85 (29%) groups (OR 0.95; 95% CI 0.49 to 1.86; p=0.88). A post-hoc analysis indicated that the trial had a low (47% conditional power) chance of detecting a statistically significant benefit from the intervention (had the target sample been achieved).

CONCLUSIONS

This study showed no evidence of benefit of 40% dextrose gel on rates of hypoglycaemia at NICU admission. Management of these vulnerable newborns should continue to focus on vascular access and commencement of dextrose-containing intravenous fluids as early as possible.

TRIAL REGISTRATION NUMBER

NCT04353713.