Continuous thoracic extradural 0.5% bupivacaine with or without morphine: effect on quality of blockade, lung function and the surgical stress response.

Twenty-two patients undergoing upper abdominal surgery were entered into a randomized, double-blind study to receive extradural (T7-T8) 0.5% bupivacaine 9 ml followed by 25 mg h-1 with or without additional extradural morphine (bolus 4 mg plus 0.5 mg h-1), for 16 h after operation. Addition of morphine was associated with total alleviation of pain, and a stable level of sensory analgesia, but not with changes in blood glucose and cortisol concentrations or postoperative impairment of lung function (PEFR, FEV1, FVC). Two patients were withdrawn because of hypotension or respiratory depression.