Organ ischemia during partial resuscitative endovascular balloon occlusion of the aorta: Dynamic 4D Computed tomography in swine

Abstract

Resuscitative endovascular balloon occlusion of the aorta (ReBoA) increases proximal pressure, and simultaneously induces distal ischemia. We aimed to evaluate organ ischemia during partial ReBoA (p-ReBoA) with computed tomography (ct) perfusion in a swine model. the maximum balloon volume was recorded as total ReBoA when the distal pulse pressure ceased. the animals (n = 4) were scanned at each 20% of the maximum balloon volume, and time-density curve (TDC) were analysed at the aorta, portal vein (pV), liver parenchyma, and superior mesenteric vein (SMV, indicating mesenteric perfusion). the area under the tDc (AUtDc), the time to peak (ttp), and four-dimensional volumerendering images (4D-VR) were evaluated. The TDC of the both upper and lower aorta showed an increased peak and delayed ttp. the tDc of the pV, liver, and SMV showed a decreased peak and delayed TTP. The dynamic 4D-CT analysis suggested that organ perfusion changes according to balloon volume. The AUTDC at the PV, liver, and SMV decreased linearly with balloon inflation percentage to the maximum volume. 4D-VR demonstrated the delay of the washout in the aorta and retrograde flow at the inferior vena cava in the highly occluded status. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been recently accepted as a feasible method of resuscitation in patients with refractory haemorrhagic shock 1-3. REBOA increases proximal blood pressure through the minimally invasive aortic occlusion 4. However, it induces distal ischaemia of the visceral organs and lower extremities, which causes inflammatory sequelae 5 and may be life threatening or limb threatening 6-8. Thus, investigating organ ischaemia during REBOA is essential, and a better understanding may contribute to the safer resuscitation of patients with haemorrhagic shock. Currently, partial REBOA (P-REBOA) is believed to mitigate distal ischaemia and to extend survival 9-12. To evaluate the degree of P-REBOA, computed tomography (CT) imaging has been employed in a swine model 13-15. The widest cross-sectional area of the balloon and the proximal or distal pressure were also used to define the degree of P-REBOA 16. However, despite recent studies, the association between the degree of P-REBOA and distal organ ischaemia has not been evaluated yet. Proximal and distal pressures are clinically measurable; however, arterial pressure may not necessarily indicate blood flow or organ ischaemia. To avoid organ dysfunction, organ ischaemia during REBOA should be investigated. Recent advancements in CT scan technology have enabled visualising organ ischaemia, and this modality has been utilised in cerebral, myocardial, or visceral organs 17-20. The objective of this study was to investigate organ ischaemia during staged P-REBOA. We analysed the time-density curve (TDC) of dynamic four dimensional

Partial Resuscitative Endovascular Balloon Occlusion of the Aorta: A Systematic Review of the Preclinical and Clinical Literature

“…17 Partial aortic occlusion demonstrates clear advantages over complete aortic occlusion in clinical and preclinical literature despite differences in study designs (including the degree of shock induced, comorbid injuries, how partial REBOA was achieved, duration of occlusion, and degree of occlusion). The literature shows that partial REBOA can reduce ongoing hemorrhage compared with no REBOA 25 preserve distal blood flow, 17,21,24,26,31,32,37 reduce ischemia or organ injury 20,24,26,31e33,37,40 extend occlusion time 20,25,49 reduce proximal hypertension 20,31,37,38 reduce resuscitation requirements compared with cREBOA 31,33,54 improve survival compared with either no REBOA or cREBOA. 20,25,26 In the animal literature, combined controlled and uncontrolled hemorrhage models are more common in the recent publications, with all but one published in 2019 and 2020.…”

Is cerebral perfusion maintained during full and partial resuscitative endovascular balloon occlusion of the aorta in hemorrhagic shock conditions?

“…Previous studies have modeled the flow distally past the pREBOA, 16 the diminished ischemic injuries to distal organs, 17,19,20 and the ease of titrating the pREBOA to modify flow when compared with the ER-REBOA. 15 This is the first study that examined the changes to proximal perfusion in a severe hemorrhagic shock model using pREBOA.…”

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) in Non-Traumatic Cardiac Arrest: A Narrative Review of Known and Potential Physiological Effects

“…Regarding the ischemia below the balloon, in the context of hemorrhage, noticeable results have been achieved by partial occlusion (p-REBOA) [39,40], which limits the bleeding allowing a minimum but sufficient perfusion of the splanchnic organs [41]. This technique is not practicable during NTCA but could be useful when ROSC is achieved.…”