Effect of Continuous Lidocaine Infusion for the Management of Cancer Pain in the Patients with Terminal Gastrointestinal Carcinoma

Abstract

Introduction: In patients with terminal gastrointestinal carcinoma, even high amounts of opioid injection may not relieve pain, resulting in neuropathic cancer pain or side effect of morphine. We conducted continuous lidocaine hydrochloride infusion and assessed the effect of pain relief and safety. Methods: From March 1999 to December 2000, 32 patients with terminal gastrointestinal carcinoma were treated with continuous infusion of 10% lidocaine hydrochloride. Those with neuropathic pain do not gain adequate pain relief using the analgesic ladder. These include patients whose opioids had to be reduced because of side effects. The effect of pain relief was assessed by reduction on the Verbal Rating Scale. Results: Average initial doses of lidocaine were 645 ± 258 mg/day, ranging from 200 to 988 mg/day. The average maintenance dose of lidocaine were 911 ± 411 mg/day, ranging from 200 to 1,440 mg/day. Lidocaine infusion lasted 30 ± 34 days, ranging from 5 to 158 days. After lidocaine infusion, 28 patients (87.5%) experienced significant pain relief, but, the effect did not last 2 weeks in 4 patients and required continuous epidural or spinal block. Skin redness was the minimum side effect obvious in all patients who underwent subcutaneous lidocaine infusion. Mental confusion or delirium visible in 4 patients was resolved after decreasing the rate of lidocaine infusion was reduced. Patients undergoing lidocaine infusion required less morphine or shorter sedation. The average morphine maintenance dose was 86 ± 84 mg/day, ranging from 10 to 345 mg/day. In 19 patients (76%), pain relief was obtained by morphine of less than 100 mg/day. Conclusion: Continuous lidocaine infusion is useful in managing cancer pain in patients with terminal gastrointestinal carcinoma, but, may not be effective in all patients. Combined pain relief including continuous epidural or spinal block may be required in patients with neuropathic cancer pain.