Rib fractures are associated with increased mortality, particularly in the elderly. While opiate-based pain regimens remain the cornerstone of rib fracture management, issues related to opioids have driven research into alternative analgesics. Adjunctive ketamine use in lieu of opioids continues to increase but little evidence exists to support its efficacy or safety within the elderly trauma population.
A prospective, randomized, double-blind placebo-controlled trial of elderly patients (age, ≥65 years) with three or more rib fractures admitted to a Level I trauma center was conducted. Exclusion criteria included Glasgow Coma Scale score less than 14, and chronic opiate use. Groups were randomized to either low-dose ketamine (LDK) at 2 μg·kg−1·min−1 or an equivalent rate of 0.9% normal saline. The primary outcome was reduction in numeric pain scores (NPS). Secondary outcomes included oral morphine equivalent (OME) utilization, epidural rates, pulmonary complications, and adverse events.
Thirty (50.8%) of 59 were randomized to the experimental arm. Groups were similar in makeup. Low-dose ketamine failed to reduce 24-hour NPS or OME totals. Subgroup analysis of 24 patients with Injury Severity Score greater than 15 demonstrated that LDK was associated with a reduction in OME utilization the first 24-hours (25.6 mg vs. 42.6 mg, p = 0.04) but at no other time points. No difference in other secondary outcomes or adverse events was noted.
Low-dose ketamine failed to affect NPS or OME within the overall cohort, but a decrease in OME was observed in those with an Injury Severity Score greater than 15. Additional studies are necessary to confirm whether LDK benefits severely injured elderly patients.
Therapeutic, level I.
From the Division of Trauma and Acute Care Surgery, Department of Surgery (N.W.K., T.W.C., W.J.P., K.B., L.B.S.), Medical College of Wisconsin, Milwaukee; Division of Critical Care Pharmacy, Department of Pharmacy, (J.J.), Froedtert Memorial Lutheran Hospital, Wauwatosa; Division of Regional Anesthesia and Acute Pain Management, Department of Anesthesia (K.M.D.), Division of Biostatistics (A.S., L.R.), Medical College of Wisconsin, Milwaukee, Wisconsin; Division of General Surgery, Department of Surgery, (J.S.P.), University of New Mexico, Albuquerque, New Mexico.
Submitted: February 15, 2019, Revised: July 20, 2019, Accepted: July 28, 2019, Published online: August 14, 2019.
Meeting Presentation: 49th Annual Meeting of the Western Trauma Association March 3–8, 2019, in Snowmass, CO.
Address for reprints: Thomas W Carver MD, FACS, Division of Trauma and Acute Care Surgery, Department of Surgery, AAST Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226; email: email@example.com.
Online date: August 16, 2019