Non-invasive continuous versus intermittent oscillometric arterial pressure monitoring and maternal hypotension during cesarean delivery: a randomized controlled trial

Abstract

Maternal hypotension frequently occurs after spinal anesthesia for cesarean delivery. We investigated whether non-invasive continuous finger-cuff arterial pressure monitoring reduces hypotension compared with intermittent oscillometric monitoring. Women undergoing planned cesarean delivery (n = 151) were randomized to the treatment (finger-cuff monitoring with blinded intermittent oscillometric monitoring) or control group (intermittent oscillometric monitoring with blinded finger-cuff monitoring). Both groups received prophylactic phenylephrine. The primary outcome was the incidence of hypotension, defined as systolic arterial pressure (SAP) < 80% of baseline SAP, from spinal anesthesia to neonatal delivery. Secondary outcomes included area under the curve (AUC), time-weighted average (TWA), and duration of SAP < 80% and < 70% of baseline. Exploratory analyses using various mean arterial pressure thresholds were also performed. Maternal adverse outcomes, phenylephrine consumption, and neonatal outcomes were assessed. The incidence of hypotension did not differ between groups (50.7% vs. 58.1%; P = 0.358). The median AUC for SAP < 80% of baseline was similar (5.0 vs. 5.2 mmHg & times; min, P = 0.467), as was the median TWA SAP < 80% of baseline (0.19 vs. 0.17 mmHg, P = 0.617). Secondary outcomes were not significantly different. Continuous finger-cuff monitoring did not significantly reduce maternal hypotension; however, the observed effect trend suggests that larger-scale trials are required to definitively determine its clinical utility.