Evaluation of continuous intraspinal narcotic analgesia for chronic pain from benign causes.

Intraspinal narcotic analgesia (INA) has been used for chronic pain from nonmalignant causes with moderate success. To ascertain the efficacy of the morphine pump, we reviewed the 2-year results of continuous INA in 18 patients with failed back syndrome or arachnoiditis and intractable, debilitating pain that was unrelieved by conventional means. All patients underwent a trial screening of single-dose intrathecal narcotics with good pain relief. After 2 years, 8 pumps were still functioning, 8 patients had the pump removed or turned off, and 2 patients were lost to follow-up. Our patients averaged 1.4 additional procedures or hospitalizations after initial pump insertion. Overall, only 4 patients had objective evidence of benefit from INA, for a success rate of 25%. Results of this review suggest INA should not be used for the long-term management of chronic pain from nonmalignant causes.