Background: Midazolam, a short-acting benzodiazepine, is administered preoperatively and intraoperatively for amnesia and anxiolysis. Subsequently, patients often do not recall events which occurred while they were sedated. Recent studies have also reported retrograde facilitation after midazolam exposure. Posttraumatic stress disorder PTSD is based on memory of a traumatic event. Because of the concern that midazolam may enhance memory of the traumatic event in which soldiers were injured, we investigated the prevalence of PTSD in those burned soldiers who received perioperative midazolam and those who did not. We also investigated the intensity of the memories related to the traumatic event.
Methods: After institutional review board approval, all charts of US soldiers who completed the PTSD Checklist-Military (PCL-M) screening tool (2004-2008) after admission to US Army Institute of Surgical Research were reviewed to determine the number of operations, the anesthetic regime, total body surface area (TBSA) burned, and Injury Severity Score (ISS).
Results: The PCL-M was completed by 370 burned soldiers from Operation Iraqi Freedom/Operation Enduring Freedom. During surgery, 142 received midazolam, whereas 69 did not. The prevalence of PTSD was higher in soldiers receiving midazolam as compared with those who did not (29% vs. 25%) (p = 0.481). Both groups had similar injuries based on TBSA and ISS. Patients who received midazolam also had similar scores on PCL-M questions related to memory of the event.
Conclusions: Rates of PTSD are not statistically different in combat casualties receiving midazolam during intraoperative procedures. Intraoperative midazolam is not associated with increased PTSD development or with increased intensity of memory of the traumatic event. Patients receiving midazolam had similar injuries (TBSA and ISS) and underwent a similar number of operations as those not receiving midazolam.