Evaluation of the concurrent use of lidocaine and ketamine infusions as adjunctive analgesia in the intensive care unit

Abstract

The purpose of this study was to determine the safety and effectiveness of ketamine and lidocaine infusions for the management of pain in surgical critically ill patients. This is a retrospective case series with a total of seven patients aged 18 years or older, had ICU stay at least 24 hours, and received concurrent use of systemic lidocaine and ketamine infusions as an adjunct therapy for pain management were enrolled between March 2014 to August 2015. The primary outcomes included the time measurement to achieve a 20% reduction in pain scores after the initiation of lidocaine and ketamine and the difference in opioid requirements pre and post concurrent pain therapies. Secondary outcomes include development of adverse events while on dual therapy. The median time to achieve a 20% pain score reduction was 2 hours. The median opioid requirements was reduced comparing prior to the ketamine and lidocaine infusions and 24 hours while on dual therapy (morphine dose equivalent 90.33 mg vs. 56 mg). Two neurological adverse events were noted. The results of this study suggest that low-dose lidocaine and ketamine infusions can be a safe and effective adjunctive treatment option for selected ICU patients with severe pain. However, future studies need to be conducted to determine the safety and effectiveness of concurrent use of lidocaine and ketamine infusions aside from surgical ICU patients.