Post-operative pain after elective Cesarean section under spinal anesthesia: primary versus repeat
Abstract Number: OP2-1
Abstract Type: Original Research
In the US, 1.4 million cesarean sections (CS) are performed annually out of which 30% are elective repeat CS (1). In a retrospective analysis, analgesic consumption after an elective CS with a spinal anesthetic was similar to that after an unplanned CS under epidural anesthesia (2). There is some suggestion that central sensitization may occur with repeated surgical procedures (3), which may suggest that women undergoing a repeat CS will require increased pain medication. To the best of our knowledge, pain outcomes and analgesic requirements in healthy women undergoing a primary elective CS have not been compared to those in women undergoing a repeated procedure under the same standardized spinal anesthetic with multimodal analgesia.
451 women scheduled for an elective CS were enrolled in this prospective longitudinal study. Spinal anesthesia was standardized (bupivacaine 12mg, fentanyl 25µg & morphine 100µg). Post-op analgesia included acetaminophen and diclofenac, iv morphine in PACU and oxycodone or tramadol for breakthrough pain. Post-op pain scores (12h, 24h, 48h) at rest, while sitting, uterine cramping and wound hyperalgesia at 48h were recorded. Pain at 8 weeks and 6 months was assessed by phone interview using brief pain inventory (BPI). Statistical analysis included t-test for equality of means (p<0.05).
304 women had a primary and 147 a repeat CS (Table). There was a trend for all pain outcomes to be higher in women undergoing a repeat CS, but only pain at rest at 48h was statistically significantly higher (p=0.05); analgesic consumption was however similar in both groups. Although pain at 6m was overall uncommon, women in the primary group reported their worst pain during the last wk as 3.0 ± 2.5 vs 4.6 ± 2.5 in women in the repeat CS group (p=0.13) (Table).
This is the first prospective report comparing pain outcomes in healthy women undergoing an elective primary or repeat CS under spinal anesthesia with multimodal post-operative analgesia. While there was a trend towards higher pain scores overall in women undergoing a repeat CS, with up to 7% of women reporting moderate pain at 6 months, the only significant difference in pain outcomes was pain scores at rest 48h. Based on these findings, women undergoing a repeat CS are unlikely to require different post-op pain management.
1 Zhang, AJOG 2010
2 Carvalho, IJOA 2010
3 Cabañero, Anesthesiol 2009