Objective: To evaluate the relationship between systolic (SBP), diastolic (DBP), mean (MBP) blood pressures and pulse pressure (PP), and left ventricular output (LVO), a surrogate of systemic blood flow.
Study design: This retrospective study included neonates who underwent targeted neonatal echocardiography (TNE) in 3-tertiary NICUs over 2 years. Associations between LVO and BP components were investigated. Analysis was adjusted for relevant covariates.
Result: 1060 studies from 485 neonates were included, with a mean GA of 28.4 ± 4.6 weeks and birth weight of 1234 ± 840 grams. LVO was associated positively with SBP and PP, and negatively with GA. PP demonstrated the highest predictive value for identifying infants with LVO < 150 ml/kg/min (area under the curve 0.75 [95% CI 0.68, 0.82]). MBP and DBP demonstrated no correlation with LVO.
Conclusion: BP parameters correlate poorly with LVO, irrespective of GA and underlying etiology. Narrow PP may be more reflective of low LVO than low SBP.