Long-term intrathecal morphine and bupivacaine in "refractory" cancer pain. I. Results from the first series of 52 patients.

Neither epidural (EDA) or intrathecal (IT) morphine nor EDA opiate + bupivacaine provides acceptable relief of some types of cancer pain, e.g. pain originating from mucocutaneous ulcers, deafferentation pain, continuous and intermittent visceral and ischaemic pain, and that occurring with body movement as a result of a fracture. To improve pain relief in such conditions, we gave combinations of morphine and bupivacaine through open IT-catheters to 52 patients with "refractory", severe (VAS 7-10 out of 10), complex cancer pain (Edmonton Stage-3), for periods of 1-305 (median = 23) days. The efficacy of the treatment was estimated from: 1) daily dosage (intraspinal and total opiates, and intraspinal bupivacaine), and 2) scores of non-opiate analgesic and sedative consumption, gait and daily activities, and amount and pattern of sleep. Forty-four patients obtained continuous and acceptable pain relief (VAS 0-2), 26 of them with daily doses of IT-bupivacaine of less than or equal to 30 mg/day (less than or equal to 1.5 mg/h). Higher IT-bupivacaine doses (greater than 60-305 mg/day), not always giving acceptable pain relief, were necessary in 13 patients with deafferentation pain from the spinal cord or brachial or lumbosacral plexuses or pain from the coeliac plexus, or from large, ulcerated mucocutaneous tumours. By combining IT-bupivacaine with IT-morphine, it was possible to use relatively low IT-morphine doses (10-25 mg/day during the first 2 months of treatment) in more than half of the patients. The IT-treatment significantly decreased the total (all routes) opiate consumption and significantly improved sleep, gait and daily activities. For the whole period of observation (6 months), the IT-treatment was assessed as adequate in 3.8%, good in 23.1%, very good in 59.6% and excellent in 13.5% of the cases. Adverse effects of the IT-bupivacaine (paraesthesiae, paresis, gait impairment, urinary retention, anal sphincter disturbances and orthostatic hypotension) did not occur with doses of 2.5-3.0 mg/h (approx. 60-70 mg/day).