Pre-Incisional Intravenous Low-Dose Ketamine Does Not Cause Pre- Emptive Analgesic Effect Following Caesarean Section under Spinal Anaesthesia

Abstract

Background: Adequate postoperative pain relief is one of the commonest challenges faced by women who deliver by caesarean section.Aim: This study was aimed at finding out the effect of pre-incisional administration of low dose intravenous ketamine on the post-operative analgesia demand time. Patients and Methods:Following approval from the Hospital's Ethical Committee, a prospective, randomised double-blind study was carried out to evaluate the pre-emptive effect of low-dose ketamine on women undergoing elective caesarean section under plain bupivacaine/fentanyl spinal anaesthesia.Results: Eighty women completed (83.33%) the study. The results were comparable in both groups for maternal age, weight, height, gestational age and parity. There was no statistical difference in the patient characteristics between the two groups under study.The mean time taken to achieve a maximal sensory level was 9.3±0.91 mins in Group-A and in Group-B 8.35±1.49 mins, p=0.260. The regression time to two segments was also the same in the two groups of women. The mean in the Group-A was 28.1±1.52 mins while the Group-B had 27.6±2.10 mins, p=0.161.The time to first analgesic request in the Ketamine Group was 193.44±26.53 mins while that for the Placebo group was 140.14±22.34 mins. The difference in the duration was statistically significant, p=0.0001. Conclusion:It is concluded that the pre-incisional administration of low-dose intravenous ketamine only demonstrated a delayed time to first analgesic request in the women who had plain bupivacaine/fentanyl spinal anaesthesia and not a pre-emptive analgesic effect.