Intravenous lidocaine relieves severe pain: results of an inpatient hospice chart review.

BACKGROUND: Parenteral lidocaine has been reported to relieve neuropathic pain and/or pain refractory to opioid therapy.

METHOD: A retrospective chart review of 768 consecutive patients acutely admitted to a hospice inpatient unit was performed to assess the efficacy and tolerability of parenteral lidocaine for pain relief.

RESULTS: Eighty-two patients (approximately 11%) received parenteral lidocaine. Typically, a patient received a parenteral bolus and pain relief was evaluated 30 minutes later. If there was an effect, a continuous infusion was started. Sixty-one patients receiving lidocaine were evaluable for pain relief response. Fifty patients (82% of evaluable patients) reported a major response of their pain to lidocaine. Five patients (8% of evaluable patients) reported a partial response. Six (10% of evaluable patients) reported no benefit.

DISCUSSION: Evaluable patients in an opioid refractory class had a 91% major response rate to lidocaine. Overall, lidocaine was well tolerated. Approximately 30% of evaluable patients reported some adverse event; the most common being lethargy. However, the effect was not clearly related to lidocaine.

CONCLUSION: Parenteral lidocaine appears to be rapidly effective for opioid refractory pain and is well tolerated. A randomized controlled trial is needed to confirm these impressive but preliminary uncontrolled results.