Renal Effects of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Therapy Following Traumatic Hemorrhagic Shock

摘要

Trauma-induced hemorrhagic shock is a leading cause of preventable death in the battlefield. The use of body armor by war fighters provides protection to the thorax, increasing the focus of research on other trauma patterns, mostly injuries to the extremities and the abdomen. Severe abdominal injuries may lead to major tissue disruption and non-compressible torso hemorrhage (NCTH). Resuscitative thoracotomy (RT) is a last resort intervention to control hemorrhage via chest opening and aortic cross clamping. RT is poorly suited for out-of-hospital scenarios and associated with a poor outcome. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as a promising replacement to RT, via the expansion of a balloon at various levels (or Zones) of the aorta to interrupt blood flow. Zone 1, 2, and 3 is comprised of the aortic segments between the subclavian and celiac arteries, between the celiac most distal renal artery, and between the distal renal artery and aortic bifurcation, respectively. While REBOA allows for hemorrhage control and augmentation of blood pressure proximal to the balloon, it also exposes distal tissue beds to ischemia and reperfusion injury. In opposition to RT, REBOA has the potential to be utilized in austere environments and would satisfy the current demand of prolonged field care. REBOA has also proven its value for civilian applications. Aware of the limitations of complete REBOA, scientists have expanded knowledge in the field of partial REBOA, whereby a minimal amount of blood flow is allowed past the balloon following a short period of complete REBOA.;The goals of this dissertation were several folds. First, we discussed the challenges posed by NCTH, including the benefits and complications associated with RT and REBOA. Second, we performed a systematic review of the evidence linking REBOA and AKI. We thoroughly reviewed studies of REBOA in both trauma patients and porcine models, and outlined the need for more consistent report of renal function in REBOA studies. Third, we established that partial REBOA could decrease the magnitude of AKI in a porcine model of traumatic exsanguination. We also reported an increase in serum angiotensin concentration which may explain those findings via preservation of renal blood flow. Fourth, we established that occlusion in Zone 3 of the aorta following Zone 1 occlusion did not provide a significant benefit to renal function. Finally, preliminary results have shown that some REBOA practices may be associated with life-threatening hyperkalemia. To maintain REBOA's relevance to the demands of prolonged field care, we validated a novel method of extracorporeal treatment of hyperkalemia compatible with austere conditions, in an anephric porcine model of hyperkalemia.;In conclusion, while REBOA is an important asset for the management of trauma patients with NCTH, complete REBOA is associated with a significant risk of AKI, which can be mitigated by new approaches such as partial REBOA. Future work should expand on the study of additional mechanisms behind AKI in NCTH patients treated with REBOA. Additionally, investigations of medical interventions, such as antioxidant drugs or extracorporeal blood purification, might prove beneficial to improve endovascular trauma patient management.