LO93: A single center randomized control trial of intravenous lidocaine for the management of traumatic rib fractures

Abstract

Introduction: Traumatic rib fractures (RF) are a common occurrence with 10% incidence in all trauma patients and are associated with significant morbidity and mortality. Adequate analgesia is paramount for preventing pulmonary complications and reducing morbidity and mortality. There is evidence of intravenous (IV) lidocaine's effectiveness and safety in the post-operative thoracic and abdominal surgical patient and we hypothesize that it may be ideal in trauma patients with RF. We evaluated IV lidocaine's analgesic efficacy in this population. Methods: A single-centre, double-blind, randomized control trial comparing a 72-96 hour IV lidocaine infusion plus standard analgesics to placebo infusion plus standard analgesics. Participants were adult trauma patients diagnosed with two or more RFs requiring hospital admission. A total of 36 patients were enrolled over 5 months in 2019. The study was powered to detect a 20% reduction in pain scores, which is determined to be clinically significant. Results: The primary outcome was mean pain score at rest and with movement, as measured on the Visual Analog Scale (VAS). There were consistent trends toward reduced VAS pain scores at rest and with movement in the lidocaine group as compared to placebo group with mean scores of 3.49 [SD 2.02 95% CI] and 7.08 [SD 1.71 95% CI] in the lidocaine group and 3.83 [SD 1.93 95% CI] and 8.03 [SD 1.44 95% CI] in the placebo group, at rest (p value 0.624) and with movement (p value 0.110), respectively . Secondary outcomes were patient satisfaction as measured on the VAS which demonstrated a score of 7.79 [SD 1.82 95% CI] in the lidocaine group and 6.63 [SD 1.77 95% CI] (p = 112) in the placebo group, and total morphine equivalents (ME) used (including breakthrough doses) that demonstrated a trend towards a reduction in the lidocaine group with 210.9 mg [SD 180.0 95% CI] compared to the placebo with total ME used of 309.9 mg [SD 221.8 95% CI]. Other secondary outcomes were protocol adherence, incidence of respiratory failure, hospital and ICU length of stay, mortality, incidence of lidocaine toxicity, and treatment regimens (non-opioid analgesics). Conclusion: These results demonstrate a trend towards lidocaine's analgesic benefit during rest and the critical times of patient movement and mobility, which has been demonstrated to be paramount in the reduction of respiratory complications from rib fractures. The results also tend towards a reduction in morphine equivalents, although the trial was not powered to demonstrate this