Double-blind evaluation of buprenorphine hydrochloride for post-operative pain

Abstract

IN A PREVIOUS STUDY it was found that buprenorphine hydrochloride is a potent analgesic and that severe post-operative pain is relieved appreciably for at least six hours by 0.4 mg or less. 1 This confirmed impressions gained from studies on animals and man currently in progress abroad. 2'3The purpose of this study was to compare the analgesic activity of buprenorphine hydrochloride 0.2 mg and 0.4 mg against each other and also against the usual standard, morphine sulphate 5 mg and 10 mg, each of which was given as a single intramuscular injection following selected major surgical procedures associated with severe post-operative pain. METHODA double-blind randomly assigned comparison was done of four groups of 40 patients, each of whom gave written informed consent agreeing to participate in the evaluation by accepting one intramuscular dose of either buprenorphine (0.2 or 0.4 mg) or morphine (5 or 10 mg) from identical serially numbered vials, if moderate to severe pain occurred in the recovery room after awakening from anaesthesia following abdominal surgery. A patient was admitted to this comparative study provided pre-operative laboratory studies were within normal limits, the investigator agreed that the patient was having severe pain post-operatively and the patient requested medication for the pain. Exclusions were specified to eliminate women of childbearing age, patients undergoing narcotic maintenance treatment or who had a history of tolerance or addiction to analgesic drugs, neurosurgery, cardiac surgery and any patient who had severe disease of vital organs, endocrine disease or haematologic disease. Those who had limited mental competence or difficulty in answering questions at the initial interview were also excluded. Patients excluded from the study received medication for pain according to standard procedures in the recovery room.No other analgesic medication was given to a patient once medicated in the test, unless severe pain was not relieved or unless severe pain recurred within two hours.Pain intensity was scored as 0 = none; 1 = mild; 2 = moderate; 3 = severe; and 4 = very severe. Pain relief was scored as 0 = no relief; 1 = slight relief; 2 = moderate relief; 3 = good relief; and 4 = complete relief. 4-r Scoring was done routinely at 30 minutes and then hourly for six hours. If no additional medication was required, the patient was kept under direct surveillance for 12 hours. Patients From:

Buprenorphine added to the local anesthetic for brachial plexus block to provide postoperative analgesia in outpatients

“…[20][21][22][23] Thus, an intramuscular injection of 0.3 mg of buprenorphine is equipotent to 10 mg of morphine, but the analgesia produced by buprenorphine lasts significantly longer. [21][22][23] This prolonged duration appears to be due to the fact that buprenorphine seems to dissociate very slowly from opioid receptors, so that the usual duration of action is about 8 hours following parenteral administration.…”

Buprenorphine as an adjuvant in supraclavicular brachial plexus block.

“…A variety of opioids have been studied for brachial plexus blockade including buprenorphine hydrochloride 5 . Buprenorphine is more potent than morphine sulphate with substantially longer duration of action and fewer side effects 6,7 . The present study was planned with the aim to evaluate and compare the effects of addition of buprenorphine in regard to the block characteristics, the quality of postoperative pain relief and the duration of analgesia, when given along with bupivacaine in supraclavicular brachial plexus block for upper limb orthopaedic surgeries.…”

Efficacy of Buprenorphine Added 2 % Lignocaine 1:80000 in Postoperative Analgesia After Minor Oral Surgery

“…• Buprenorphine hydrochloride is at least 50 times more potent than morphine sulphate and has substantially longer duration of action [11][12][13].…”