Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging technology to augment proximal blood pressure during the resuscitation of patients with noncompressible torso hemorrhage. Currently, placement choice, supraceliac (Zone 1) versus infrarenal (Zone 3) aorta, depends on injury patterns, but remains a highly debated topic. We sought to compare the proximal hemodynamic support provided by Zone 1 versus Zone 3 REBOA placement and the degree of hemodynamic instability upon reperfusion following intervention.
Eighteen anesthetized swine underwent controlled hemorrhage of 25% total blood volume, followed by 45 minutes of Zone 1 REBOA, Zone 3 REBOA, or no intervention (control). They were then resuscitated with shed blood, aortic balloons were deflated, and 5 hours of critical care ensued prior to euthanasia. Physiologic parameters were recorded continuously, and blood was drawn for analysis at specified intervals. Significance was defined as p < 0.05.
There were no significant differences between groups at baseline or during the initial 30 minutes of hemorrhage. During the intervention period, average proximal MAP was significantly greater in Zone 1 animals when compared with Zone 3 animals (127.9 ± 1.3 vs. 53.4 ± 1.1 mm Hg) and greater in Zone 3 animals when compared with control animals (42.9 ± 0.9 mm Hg). Lactate concentrations were significantly higher in Zone 1 animals (9.6 ± 0.4 mmol/L) when compared with Zone 3 animals (5.1 ± 0.3 mmol/L) and control animals (4.2 ± 0.8 mmol/L).
In our swine model of hemorrhagic shock, Zone 3 REBOA provided minimal proximal hemodynamic support when compared with Zone 1 REBOA, albeit with less ischemic burden and instability upon reperfusion. In cases of impending hemodynamic collapse, Zone 1 REBOA placement may be more efficacious regardless of injury pattern, whereas Zone 3 should be reserved only for relatively stable patients with ongoing distal hemorrhage.
From the Clinical Investigation Facility, David Grant USAF Medical Center, Travis Air Force Base, California (E.M.T., G.L.H., M.A.S., A.J.D., E.S.D., E.R.F., L.P.N., J.K.G., T.K.W); Department of General Surgery, David Grant USAF Medical Center, Travis Air Force Base, California (E.M.T., A.J.D., E.S.D.); Department of Surgery, University of California Davis Medical Center, Sacramento, California (E.M.T., M.A.S., A.J.D., E.S.D., J.J.D.); Heart, Lung, and Vascular Center, David Grant USAF Medical Center, Travis Air Force Base, California (M.A.S., J.J.D., T.K.W.); Department of Surgery, University of Maryland Medical Center, Baltimore, Maryland (J.J.D.); Department of Surgery, Emory University Hospital, Atlanta, Georgia (L.P.N.); Department of Surgery, Wake Forest Baptist Medical Center, Winston-Salem, North Carolina (T.K.W.); Department of Emergency Medicine, University of California Davis Medical Center, Sacramento, California (M.A.J.).
Submitted: November 28, 2017, Revised: January 18, 2018, Accepted: January 31, 2018, Published online: February 27, 2018.
Address for reprints: Emily M. Tibbits, MD, 2315 Stockton Blvd, OP512, Sacramento, CA 95817; email: email@example.com.
Funding for this study was provided by the Clinical Investigation Facility, David Grant USAF Medical Center, Travis Air Force Base, California.
These findings were presented at the 31st Annual Scientific Assembly of the Eastern Association for the Surgery of Trauma, January 9 to 13, 2018, in Lake Buena Vista, Florida.
The animals involved in this study were procured, maintained, and used in accordance with the Laboratory Animal Welfare Act of 1966, as amended, and NIH 80-23, Guide for the care and Use of Laboratory Animals, National Research Council. The views expressed in this material are those of the authors and do not reflect the official policy of the US Government, the Department of Defense, the Department of the Air Force, or the University of California Davis. The work reported herein was performed under US Air Force Surgeon General–approved Clinical Investigation No. FDG20160026A and FDG20170005A.