2021 Trauma/Critical Care Presentations

Derek Benham1; Matthew Carr, MD1; Lyndsey Wessels1; Joseph Lee2; Richard Calvo3; Andrew Schrader1; Torbjorg Holtestaul4; Daniel Lammers4; Ian Jones4; Jeffrey Connnor4; Jessica Weiss4; Eckert Matthew4; Michael Krzyzaniak1; Matthew Martin3; 1Naval Medical Center San Diego; 2Uniformed Services University of the Health Sciences; 3Scripps Mercy; 4Madigan Army Medical Center

Objectives: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is being increasingly used for noncompressible truncal hemorrhage, and has been used by the United States Military in austere operating environments. In emergency and lower resource or battlefield settings, the requirement for an arterial line setup and monitor is prohibitive. Our aim is to evaluate the accuracy and precision of the Centurion COMPASS device versus standard arterial pressure monitoring in a swine model using both standard ER-REBOA and partial REBOA (pREBOA).

Methods: 40 swine underwent a 4-phase validation/precision study (each phase using 5 ER-REBOAs and 5 pREBOAs). Phases I/II evaluated accuracy with ER-REBOA and pREBOA in uninjured animals. Phases III/IV duplicated the previous phases but in a severe hemorrhagic shock model. Carotid and femoral pressures were monitored with both arterial line and COMPASS device, vascular flow was measured by aortic and superior mesenteric arterial flow probes.

The hemorrhage model consisted of a 20% total blood volume (TBV) controlled hemorrhage, via a central line, followed by a iliac vein injury to create uncontrolled severe hemorrhagic shock.

A resuscitation algorithm was used consisting of a 250cc bolus of Hextend to all animals if their MAP fell below 40mmHg. If the MAP remained or fell below 40mmHg, then the previously preserved 20% TBV was transfused. The animal was euthanized if the MAP fell and stayed below 20mmHg.

Statistical analysis consisting of correlation and Bland-Altman analyses were performed.

Results: There was strong correlation in accuracy testing of proximal and distal COMPASS devices compared to standard arterial line monitoring (r=0.94, 0.8; p<.005) as well as during precision testing (r = .98, .89 p < .005) in the uninjured phases. Similar accuracy and reliability were demonstrated in hemorrhagic shock, with strong correlation for the proximal and distal COMPASS devices (r =.98, .97; p<.005), as well as during precision testing (r=.99, .95; p<.005) in both full and pREBOA scenarios. Bland-Altman analysis (Figures) showed extremely low bias between the COMPASS and arterial line for both proximal (bias=1.9) and distal (bias=0.8) pressure measurements.

Conclusion: The COMPASS provided accurate and precise measurements of both proximal and distal arterial pressures during standard and pREBOA in uninjured and shock conditions. This device may help extend REBOA capability to low resource or battlefield settings or even eliminate the need for arterial line setup in any emergency setting.