Effect on neonatal outcomes of maintenance of maternal blood pressure targets with noradrenaline after spinal anaesthesia for caesarean delivery: a multicentre, randomised, controlled trial.

Summary

In 1183 women undergoing cesarean under spinal anesthesia, targeting systolic BP within 90% (vs 80%) of baseline using noradrenaline boluses did not change mean umbilical artery pH but reduced the incidence of umbilical artery pH <7.2. Maternal hypotension, severe hypotension, and nausea/vomiting were significantly less frequent in the 90% target group.

Key Findings

• Mean umbilical artery pH was similar between SBP-90% and SBP-80% targets (7.33 vs 7.33).
• Umbilical artery pH <7.2 was less frequent with the 90% target (0.5% vs 2.2%; p=0.020).
• Maternal hypotension (<80% baseline), severe hypotension (<60%), and nausea/vomiting were all significantly reduced with the 90% target.
• Achieving the 90% target required more noradrenaline boluses (median 2 vs 1).

Clinical Implications

For cesarean delivery under spinal anesthesia, maintaining systolic BP ≥90% of baseline with noradrenaline boluses may reduce neonatal acidaemia and maternal hypotension-related symptoms. Protocols should consider higher BP targets while monitoring for vasopressor overuse.

Limitations

• Noradrenaline bolus regimen may limit generalizability to other vasopressors or infusion strategies
• Short-term neonatal outcomes emphasized; longer-term outcomes not reported

Future Directions

Compare continuous vs bolus vasopressor strategies and evaluate long-term neonatal neurodevelopment under different BP targets; assess applicability in emergency cesarean and high-risk populations.