Bi-manual proximal external aortic compression after major abdominal-pelvic trauma and during ambulance transfer: A simulation study.
BACKGROUND
Applying manual pressure after hemorrhage is intuitive, cost-free, and logistically-simple. When direct abdominal-pelvic compression fails, clinicians can attempt indirect proximal-external-aortic-compression (PEAC), while expediting transfer and definitive rescue. This study quantifies the sustainability of simulated bi-manual PEAC both immediately on scene and during subsequent ambulance transfer. The goal is to understand when bi-manual PEAC might be clinically-useful, and when to prioritize compression-devices or endovascular-occlusion.


METHODS
We developed a simulated central vessel compression model utilizing a digital scale and Malbrain intra-abdominal pressure monitor inside a cardiopulmonary resuscitation mannequin. Twenty prehospital health care professionals (HCPs) performed simulated bimanual PEAC i) while stationary and ii) inside an 80km/h ambulance on a closed driving-track. Participants compressed at "the maximal effort they could maintain for 20min". Results were measured in mmHg applied-pressure and kilograms compressive-weight. The Borg scale of perceived-exertion was used to assess sustainability, with <16 regarded as acceptable.


RESULTS
While stationary all participants could maintain 20min of compressive pressure/weight: within five-percent of their starting effort, and with a Borg-score <16. Participants applied 88-300mmHg compression pressure; (mean 180mmHg), 14-55kg compression-weight (mean 33kg), and 37-66% of their bodyweight (mean 43%). In contrast, participants could not apply consistent or sustained compression in a moving ambulance: Borg Score exceeded 16 in all cases.


CONCLUSIONS
Survival following major abdominal-pelvic hemorrhage requires expedited operative/interventional rescue. Firstly, however, we must temporize pre-hospital exsanguination both on scene and during transfer. Despite limitations, our work suggests PEAC is feasible while waiting for, but not during, ambulance-transfer. Accordingly, we propose a chain-of-survival that cautions against over-reliance on manual PEAC, while supporting pre-hospital devices, endovascular occlusion, and expeditious but safe hospital-transfer.
Royal Alexandra Hospital Emergency Department, Alberta Health Services, Canada. Electronic address: matthew.douma@albertahealthservices.ca.
M J
MJ
Douma
Edmonton Zone Emergency Departments, Alberta Health Services, Canada.
D
D
O'Dochartaigh
Department of Critical Care Medicine, University of Alberta Hospital, Edmonton, Alberta, Canada. Electronic address: peter.brindley@ahs.ca.
P G
PG
Brindley
D000007:Abdominal Injuries / Q000628:therapy*; D000328:Adult; D000552:Ambulances; D001012:Aorta, Abdominal / Q000293:injuries*; D001835:Body Weight / Q000502:physiology; D002170:Canada; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D018592:Cross-Over Studies; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D006470:Hemorrhage / Q000517:prevention & control*; D006489:Hemostatic Techniques / Q000295:instrumentation; D006801:Humans; D008297:Male; D008348:Manikins; D016544:Patient Simulation; D010360:Patient Transfer; D011312:Pressure; D011446:Prospective Studies; D055815:Young Adult
Junctional hemorrhage; Noncompressible torso hemorrhage; Prehospital care