Effect of preoperative pregabalin on post-caesarean delivery analgesia: a dose-response study.

Introduction: We hypothesised that preoperative administration of a single-dose of pregabalin would be associated with lower morphine consumption after uncomplicated caesarean delivery.

Methods: After Institutional Ethics Committee approval, 135 parturients scheduled for elective caesarean delivery under spinal anaesthesia were randomly allocated to receive either placebo, or oral pregabalin 150mg or 300mg, one hour before induction of anaesthesia. Maternal cumulative morphine requirement at 24h, pain scores, sedation scores, nausea and vomiting, pruritus, pregabalin-related adverse effects, Apgar scores, Neurologic and Adaptive Capacity scores and umbilical cord acid-base status were recorded.

Results: Compared with placebo or pregabalin 150mg, the use of a preoperative dose of pregabalin 300mg resulted in significantly lower cumulative morphine consumption at 24h (mean dose: placebo 12.9mg [95% CI 11.6 to 14.2]; pregabalin 150mg 11.9mg; [95% CI 10.7 to 13.1]; pregabalin 300mg 6mg [95% CI 5.4 to 7.3]; P<0.001). Pregabalin 300mg resulted in lower pain scores at 4h and 6h after delivery (P<0.001), and fewer instances of nausea, vomiting and pruritus (P<0.009). Dizziness and abnormal vision were observed most frequently in the pregabalin 300mg group (P<0.05 and P<0.009, respectively). The three groups were similar in terms of maternal sedation, Apgar scores, Neurologic and Adaptive Capacity scores and umbilical cord acid-base status. Three babies in the pregabalin 300mg group (6.7%) experienced short-term poor latching-on for breastfeeding.

Conclusion: In our study, preoperative administration of pregabalin 300mg reduced postoperative morphine consumption and early postoperative pain in parturients undergoing elective caesarean delivery, although maternal side effects were more common.