Post-operative analgesic effect of dexmedetomidine administration in wound infiltration for abdominal hysterectomy: A randomised control study

BACKGROUND AND AIMS: Local infiltration of the surgical wound is one of the important components of multimodal analgesia for post-operative pain relief. This study determines the post-operative analgesic effect of addition of dexmedetomidine to bupivacaine for local infiltration of the surgical wound. METHODS: Sixty women belonging to American Society of Anesthesiologists’ Grade 1 or 2 posted for abdominal hysterectomy were randomly allocated to Group I (control group) where patients received wound infiltration with 30 mL 0.25% bupivacaine at the end of surgery, or Group II, where patients received wound infiltration with 1.0 μg/kg dexmedetomidine diluted in 30 mL 0.25% bupivacaine. The primary objective of the study was to assess post-operative pain scores. Number of patients requiring rescue analgesia and total morphine consumption during 24 h after surgery were also recorded. Statistical significance for analgesic requirement was determined by one-way analysis of variance. RESULTS: Pain scores were lower at rest for 12 h and on cough for 6 h in Group II (<0.01). All patients in Group I required supplemental morphine compared to only 3 patients in Group II (P < 0.003). Post-operative analgesia requirement was significantly less in patients receiving dexmedetomidine in wound infiltration compared to patients receiving bupivacaine alone (P < 0.001). CONCLUSIONS: Wound infiltration of dexmedetomidine with bupivacaine provides superior pain relief compared to bupivacaine alone.