Blunt Abdominal Trauma, Splenectomy, and Post-Splenectomy Vaccination

BACKGROUND

Unlike penetrating abdominal injuries where the decision to operate is relatively straight forward, those combat casualties that sustain Blunt Abdominal Trauma (BAT) offer more of a diagnostic and clinical challenge. With the improvements in body armor, truncal injury has decreased despite increasingly more lethal weapon systems. With the advent of Improvised Explosive Devices (IEDs), however, more casualties are presenting with evidence of BAT. While Computed Tomography (CT) scans are available to assist the provider in decision making at a Role 3 facility, providers at far forward surgical units must decide to operate based on a physical and a focused assessment with sonography for trauma (FAST) exam.1

It is incumbent on the senior surgeon at each facility to ensure the staff understands their resource limitations and the inherent limitations associated with the use of the FAST exam to diagnose a hemoperitoneum. For hemodynamically unstable trauma patients with a positive FAST, exploratory laparotomy should be undertaken immediately. Rarely, patients with a positive FAST and/or CT scan may be managed non-operatively if they are already at a Role 3 facility that can ensure adequate clinical follow-up and evaluation. Patients who have a positive FAST exam and/or evidence of hemoperitoneum through CT at a surgical facility should not be transferred until any and all ongoing intraabdominal hemorrhage is completely assessed and controlled. The benefits of non-operative management do not outweigh the risks of an in-flight hemorrhagic emergency with no potential for therapeutic surgical intervention. Patients who evolve peritonitis by physical exam or continue to consume blood products in order to maintain blood pressure warrant exploratory laparotomy. An algorithmic approach to the blunt trauma patient is presented in Appendix A.

Splenic injury grading is presented in Table 1 below. All grade IV-V splenic injuries should undergo splenectomy due to the high risk of failure of non-operative management with or without splenic embolization2 and the need for prolonged transportation out of theater. Lacerated spleens of any grade with active hemorrhage encountered during laparotomy for any reason are best managed by splenectomy. If the tactical situation permits stable grade III splenic injuries without active extravasation, pseudo aneurysm, hemoperitoneum on CT scan or other indications for laparotomy that may include, but are not limited to associated injury may undergo attempt of non-operative management under the direct supervision of an experienced trauma surgeon.3 Ideally, patients undergoing attempted splenic salvage should be monitored in the Role 3 facility for at least 48 hours prior to strategic evacuation out of theater. In Role 3 facilities with interventional radiology capabilities, embolization of grade III splenic injuries may be considered as an adjunct to non-operative management. Embolization is not definitive treatment for splenic injuries so these patients must also be monitored for 48 hours following the procedure and prior to strategic aeromedical evacuation from theater.

A contrast CT scan should be obtained at 48 hours (and before aeromedical evacuation out of the Role 3 to assess for complications such as pseudonaneurysm formation on all patients undergoing non-operative management of splenic injury.4 Indicators of failure of non-operative management of the spleen include but are not limited to any need for blood transfusion and any hypotensive episode. For Grade I-III splenic injuries success rate of non-operative management with embolization reach 99-100%. Patients who fail non-operative management of the spleen require splenectomy at the Role 3 prior to aeromedical evacuation. It must be stressed that placing a patient in the aeromedical environment is akin to discharge from the facility without activity restriction and without the option of re-admission during the complete inter-facility transport between theaters which must be assumed to be a minimum of 12 hours. Additionally, the patient’s history should be discussed between the referring and accepting surgeons prior to evacuation. Patients with Grade III splenic injury and Traumatic Brain Injury (TBI) should undergo splenectomy due to the fact that hypotension with TBI will double mortality.5 Angiography and embolization for blunt injuries of other visceral organs may be used as an adjunctive procedure and should be determined on a case by case basis.