Long-Term Intrathecal (IT) Administration of Opioid and Bupivacaine Relieved Intractable Pain in a Patient with Familial Amyloidosis Polyneuropathy: A Case Report

Abstract

Introduction. At the present time, there is no reliable method or drug for effective relief of the severe pain caused by the amyloldotic polyneuropathy (AP). Objective. To explore the possibility of relieving this type of pain by intrathecal (IT) infusion of opioid (morphine or buprenorphine), with or without bupivacaine. Patients, Materials and Methods. A 49-year-old male AP patient with Intractable pain in the low back, lower abdomen, and lower extremities. Opioids (up to 20 mg parenteral morphine-eq/day), and epidural injections of morphine (up to 36 mg/day) failed to provide long-term satisfactory pain relief. Therefore, an IT catheter was inserted via the L3-L4 interspace with its tip located at the L1-L2 intervertebral disk. Results. Intermittent IT injections of morphine from 5 to 30 mg per day, for 124 days, and continuous IT infusion of morphine (2-4 mg/ml), combined with bupivacaine (1.0-2.0 mg/ml), in daily rates from 2 to 12 ml (median = 9.5) for another 67 days, were associated with occurrence of seizures, suspected to be caused by the IT morphine. Therefore, the IT morphine was replaced with IT buprenorphine. Thereafter, the pain was treated with IT infusion of buprenorphine (0.06 mg/ml) and bupivacaine (1.25 mg/ml) in daily rates from 4 to 13 ml (median = 5) for another 676 days, until the patient's death, for reasons unrelated to the IT treatment. He experienced satisfactory pain relief with daily doses of IT opioid from 4.5 to 39 mg morphine-eq (median = 19.6 mg) and IT bupivacaine from 0 to 20 (median = 12.5). The mean visual Analog Scores (VASmean), decreased from 7 to 0 (out of 10), the gait improved; and nocturnal sleep increased from 1 to 7-8 hours. Respiratory insufficiency (attributed to an an IT daily dose of ∼ 5 mg morphine) and orthostatic hypotension, pareses, and urinary retention occurring at low doses of (12-18 mg/day) of IT bupivacaine were recorded. The patient had the IT treatment for 867 days, of which 777 days (> 90%) were spent at home. Conclusion. Long-term IT administration of opioid and bupivacaine provided satisfactory long-term pain relief in a patient with refractory pain due to AP.