Effect of pneumatic leg compression on phenylephrine dose for hypotension prophylaxis via variable rate infusion at cesarean delivery: an unblinded randomized controlled trial

Background

Phenylephrine infusion is recommended to prevent spinal hypotension during cesarean delivery (CD) but may be associated with dose-dependent side effects. We hypothesized that adding intermittent pneumatic compression (IPC) of the lower legs to a variable-rate phenylephrine infusion will reduce the dose of phenylephrine required during CD.

Methods

Seventy-six healthy women undergoing elective CD under combined spinal-epidural anesthesia were randomly assigned to IPC or control groups (n = 38 per group). After spinal anesthesia, IPC of the lower legs was initiated in the IPC group, and all women received a phenylephrine infusion starting at 25 μg·min⁻¹ and increasing by 16.7 μg·min⁻¹ for systolic blood pressure (SAP) < 90% baseline. If hypotension (SAP < 80% baseline) occurred, 100 μg phenylephrine bolus was administered. The primary outcome was the dose of phenylephrine per minute.

Results

The dose of phenylephrine per minute (34.4 ± 7.3 μg·min⁻¹ vs. 40.9 ± 9.5 μg·min⁻¹, P = 0.001; mean difference −6.6 μg·min⁻¹, 95% CI −10.5 to −2.7 μg·min⁻¹) and the incidence of hypotension (24% vs. 55%, P = 0.005) were lower in the IPC group than in the control group. There were no significant differences between the two groups in the total dose of phenylephrine (603.2 ± 217.1 μg vs. 706.2 ± 247.5 μg, P = 0.058; mean difference −102.9 μg, 95% CI −209.4 to 3.5 μg), maternal side effects, or neonatal outcomes.

Conclusions

Intermittent pneumatic compression combined with a variable-rate phenylephrine infusion reduced the phenylephrine dose per minute and the incidence of hypotension during CD under spinal anesthesia.