062 - Association of low superior vena cava flow among preterm neonates during perinatal transition and neonatal outcomes: A systematic review and meta-analysis.

Publication Number: 62.3593

Nishkal Persad, University of Toronto Temerty Faculty of Medicine, Mississauga, ON, Canada; Dwayne Mascarenhas, The Hospital for Sick Children, Toronto, ON, Canada; Catherine Devion, Sunnybrook Health Sciences Centre, Toronto, ON, Canada; Bonny Jasani, The Hospital for Sick Children, Toronto, ON, Canada; Poorva Deshpande, Mount Sinai Hospital, Toronto, ON, Canada; Prakesh S. Shah, Mount Sinai Hospital, Toronto, ON, Canada; Dany E. Weisz, University of Toronto, Toronto, ON, Canada

Background: Survival with normal neurodevelopment is the primary goal of contemporary neonatal intensive care. Cerebral haemorrhage is a common, primary contributor to neurodevelopmental impairment and may occur, in part, due to low cerebral blood flow. Identifying preterm neonates at risk of intraventricular haemorrhage (IVH) and/or mortality may permit interventions to improve these critical outcomes. Low superior vena cava flow (SVCF) on echocardiography in the first 24-48 hours after birth has been variably associated with adverse outcomes.

Objective: To evaluate the association of low superior vena cava flow (SVCF), diagnosed on echocardiography in the first 48 hours after birth, with adverse morbidity and mortality, among very preterm neonates.

Design/Methods: A systematic review and meta-analysis of relevant studies was conducted to examine the association between low SVCF in the first 48 hours after birth and morbidity and mortality in preterm neonates < 32 weeks gestational age. PROSPERO, OVID Medline, EMBASE, Cochrane Library, CNKI and Google scholar were searched from inception to November 2023. Screening, selection and data extraction of eligible studies was conducted independently by two study authors. Odds ratios for the primary outcome of IVH (any and severe) as well as secondary outcomes such as mortality, PVL, NDI and NEC were generated by pooling unadjusted estimates using a random effects meta-analysis. Risk of bias for each individual outcome was assessed using QUIPS tool. The certainty of evidence was evaluated using the GRADE System for prognostic studies.

Results: Seventeen studies enrolling 1717 patients were included (444 with low SVCF and 1273 with normal SVCF). For the primary outcome of IVH (any and severe), 11 and 10 studies were included in the meta-analyses respectively. Low SVCF was associated with statistically significant increased odds of any IVH (OR 3.00, 95% CI 1.84-4.91, 11 studies, n=1122, I2=28%, moderate certainty) ); severe IVH (OR 4.83 95% CI 2.54 - 9.19, 10 studies, n=996, I2= 19%, moderate certainty) in the first seven days after birth and all-cause mortality prior to discharge from hospital (OR 4.17, 95% CI 1.80 - 9.66, 6 studies, n=724, I2 = 39%, low certainty). There were no differences between groups for the other secondary outcomes. The certainty of evidence was rated as moderate for the primary outcome and low to very low for secondary outcomes.

Conclusion(s): Low SVCF in the first 48 hours of life for preterm infants born < 32 weeks is associated with increased odds of any and severe IVH as well as increased mortality before discharge.

Figure 1. Forest plot for outcome of any IVH
Pooled OR of unadjusted estimate for the outcome of IVH: OR 3.00; 95% CI[1.84 - 4.91]; p -value < 0.001

Figure 2. Forest plot for outcome of severe IVH
Pooled OR of unadjusted estimate for the outcome of severe IVH: OR 4.83; 95% CI [2.54 - 9.19]; p-value <0.001

Figure 3. Forest plot for the outcome of all-cause mortality
Pooled OR of unadjusted estimate for outcome of mortality: OR 4.17; 95% CI [1.80 – 9.66]; p-value 0.0072

Figure 1. Forest plot for outcome of any IVH
Pooled OR of unadjusted estimate for the outcome of IVH: OR 3.00; 95% CI[1.84 - 4.91]; p -value < 0.001

Figure 2. Forest plot for outcome of severe IVH
Pooled OR of unadjusted estimate for the outcome of severe IVH: OR 4.83; 95% CI [2.54 - 9.19]; p-value <0.001

Figure 3. Forest plot for the outcome of all-cause mortality
Pooled OR of unadjusted estimate for outcome of mortality: OR 4.17; 95% CI [1.80 – 9.66]; p-value 0.0072