Prospective cohort study examining the use of regional anesthesia for early pain management after combat-related extremity injury

Background: No studies have examined the long-term benefits of regional anesthesia (RA) for pain management after combat-related injury. The objective of this prospective cohort study was to examine the relationship between RA administration and patient-reported pain-related outcomes among Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) service members sustaining a combat-related extremity injury.

Methods: Between 2007 and 2013, n=358 American military personnel injured in OEF/OIF were enrolled at two military treatment facilities. Individuals were followed for up to 2 years after injury. Cohorts were defined based on whether participants were administered RA within 7 days after sustaining a combat-related injury, or not. Linear mixed effects models examined the association between RA and average pain intensity. Secondary outcomes included pain relief, pain interference, neuropathic pain symptoms, treatment outcomes related to pain management, and mental health symptoms.

Results: Receiving early RA was associated with improved average pain over the first 6 months after injury (β=-0.57; p=0.012) adjusting for injury severity and length of stay at the primary treatment facility. This difference was observed up to 24 months after injury (β=-0.36; p=0.046). Individuals receiving early RA reported greater pain relief, improved neuropathic pain intensity, and higher satisfaction with pain outcomes; however, by 24 months, mean scores did not significantly differ between cohorts.

Conclusion: Findings indicate that when administered soon after traumatic injury, RA is a valuable pain management intervention. Future longitudinal studies investigating the timely delivery of RA for optimal pain management in civilian trauma settings are needed.

Trial registration number: NCT00431847.