Pre-incisional caudal epidural blockade and the relief of pain after lumbar spine operations.

We report the effect of pre-incisional caudal epidural injection of a mixture of 20 ml 0.25% bupivacaine and 0.1 mg buprenorphine performed under general anaesthesia for relieving wound pain after posterior interbody fusion and laminotomy for spinal stenosis. Pain was compared in groups with and without blockade: 24 and 23 patients with fusion, and 30 and 28 with laminotomy respectively. In the first 12 h after each operation, the group with blockade required additional analgesics less frequently and had a lower visual analogue scale score than those without blockade. In, and after, the second 24 h patients with hypotension of 10 mm Hg, or more, after the blockade required additional analgesics less frequently than those without blockade for both operations and had a lower visual analogue score than those without blockade for laminotomy, but not for fusion. This is a simple procedure for relieving wound pain and in patients with hypotension caused by the block, the effect continued even after the analgesic action had disappeared.