A novel method of polytrauma with traumatic brain injury and hemorrhage in swine

Traumatic brain injury (TBI) is a leading cause of death in polytrauma; however, conflicting treatment guidelines indicate a need for further research on optimal resuscitation strategies for TBI and hemorrhage polytrauma. While large animal models are commonly used due to their physiological similarities to humans, few models demonstrate both TBI and uncontrolled abdominal hemorrhage simultaneously, which requires animals to be positioned supine. This study aimed to develop a reproducible swine model of TBI in the setting of uncontrolled abdominal hemorrhage, using an electronically controlled cortical impactor (eCCI) to induce TBI and facilitate concurrent liver injury via laparotomy. A custom stereotactic frame and impactor mount were built to accommodate the unique supine positioning. An electromotive force sensor built into the custom impactor tip was used to establish the impactor set point at the dural border. In 11 swine, eCCI readings showed a mean TBI impact velocity of 3.46 m/s (SD 0.041) and depth of 10.77 mm (SD 0.042) compared to programmed values of 4.0 m/s and 10.99 mm respectively. This model effectively produced reproducible TBI eCCI calibration and impact measurements, demonstrating the feasibility of inducing concurrent injuries in a supine TBI polytrauma swine model.