Aspects of hepatoduodenal trauma and fluid therapy in hemorrhagic shock

Sammanfattning: Traumatic injury is the leading cause of death among young adults and children, accounting for 5 million deaths worldwide on an annual basis. In Sweden alone, 2500 individuals succumb to traumatic injuries yearly. Beyond the burden of death, injuries contribute to a large proportion of disability. Hemorrhagic shock and severe abdominal injuries are frequent causes of preventable death after trauma, whereas early recognition and proper treatment of these conditions improve survival considerably. The aim of this thesis is to review some aspects of abdominal injuries and fluid therapy in hemorrhagic shock. Paper I evaluated the population-based incidence and injury severity of the most frequently injured abdominal organ, the liver, in the County of Stockholm comprising 1.75 million inhabitants. Cases of liver injuries were retrieved from the National Board of Forensic Medicine and the Public Health and Medical Services Committee Register (in-patients register). The results show a relatively low incidence of liver injuries in the studied population (2.95/100,000). The hazard of liver injury in the County was calculated to be 0.003% per annum. Grade II and III injuries prevail. Nonoperative management was applied in 54% of patients. Only simple operative measures were employed in the 32% of surgically explored patients. No complex hepatic injuries were operated upon. The nonoperative management of liver injuries is mounting and is currently employed around the world. The objective of paper II was to describe a simplified surgical algorithm for the treatment of lowvelocity duodenal gunshot injuries currently in use in a large South African civilian trauma center and to verify its validity by measuring morbidity and mortality. Seventy-five consecutive patients with gunshot injuries to the duodenum were reviewed. Primary repair was performed in 86%, a resection and re-anastomosis in 11% and pancreatoduodenectomy in 3% of patients. The overall morbidity and mortality was 58% and 28%, respectively. Most civilian low-velocity duodenal gunshot injuries are treated with simple primary repair resulting in overall morbidity, mortality, and duodenum-related complication rates comparable to those in reports where more complex surgical procedures are employed. Primary repair is also applicable in the majority of combined pancreatic and duodenal gunshot wounds. Few previous studies have been conducted on prehospital management of hypotensive trauma patients in Stockholm County and therefore a retrospective review of these patients is discussed in paper III. We found that the mean time interval at the scene of injury (19 min) exceeded Prehospital Trauma Life Supports general guidelines (10 min). Most of the hypotensive trauma patients were fluidresuscitated on the scene of injury regardless of the type, mechanism, or severity of injury. A predefined fluid resuscitation regimen is not employed in hypotensive trauma victims with different types of injuries. The outcome was worsened by male gender, progressive age and an Injury Severity Score >20. In paper IV, we discuss an experimental study on a porcine model of near-lethal liver injury associated with hemorrhagic shock. We hypothesized that early intravenous fluid therapy does not improve shortterm survival, the volume of intraabdominal hemorrhage, and aortic and visceral hemodynamics. We found no differences in these parameters when animals were randomized into early or delayed resuscitation groups, receiving intravenous hypertonic saline dextran either 20 minutes or 40 minutes after trauma. We concluded that rebleeding after severe liver injury occurs infrequently; hepatic hemodynamics and short-term survival were not improved by the early initiation of fluid therapy.