POSTOPERATIVE ANALGESIA

A COMPARISON OF SUBLINGUAL BUPRENORPHINE AND INTRAMUSCULAR MORPHINE FOR PAIN RELIEF AFTER ABDOMINAL HYSTERECTOMY

Abstract

Objective: To determine the effectiveness of sublingual buprenorphine
in terms of duration of action, quality of analgesia, convenience of administration and safety, as compared to
intramuscular morphine for postoperative analgesia after abdominal hysterectomy. Design: Prospective,
randomized and comparative study. Place and duration of study: Combined Military Hospital Jhelum, from
January, 2001 to October, 2003. Subjects and methods: Women undergoing abdominal hysterectomy were
randomly assigned to receive postoperative analgesia with sublingual buprenorphine 0.007 mg/kg body weight
or intramuscular morphine 0.2 mg/kg body weight. No analgesic was used before or during anaesthesia. First
dose of analgesic was given when patients complained of pain after recovery and doses repeated on required
basis. Main outcome measures was effectiveness of analgesia as measured by modified VAS and four point
verbal rating scale. Secondary outcome measures were degree of sedation, respiratory rate and blood pressure.
Results: Both drugs provided effective postoperative analgesia but buprenorphine provided slightly better pain
relief for a much longer duration and thus required fewer doses (p=.ooo as determined by Pearson chi-square
test ). Onset of action was slower for buprenorphine (36.8±5.7 mins) as compared to morphine (12.2±2.7 mins).
Mean arterial blood pressure remained stable in buprenorphine group but slightly decreased in morphine group.
Respiratory rate slightly reduced in both groups. The incidence of adverse reactions like nausea, vomiting and
drowsiness were slightly more common in buprenorphine as compared to morphine group. Conclusion: Both
drugs provide equally effective postoperative analgesia. Ease of administration and longer duration of action
of sublingual buprenorphine make it a more acceptable option.