pelvic and junctional hemorrhage have been reported in-hospital and
in combat theaters. Prehospital Zone III REBOA has been reported
and implementation of prehospital Zone I REBOA is forthcoming.
The use of REBOA for hemorrhage control in nontraumatic
conditions, such as severe peripartum obstetrical hemorrhage, has
also been increasing with favorable outcomes reported. Strategies
for intermittent and graded partial aortic occlusion are maturing
and offer the prospect of extending aortic balloon hemorrhage
control while limiting distal ischemia.
The use of aortic balloon occlusion to augment coronary
perfusion pressure during CPR chest compressions has been
studied in laboratory models and evidence of increased coronary
perfusion pressure has been reported. Clinical trials to investigate
REBOA in medical cardiac arrest are being pursued.
Selective Aortic Arch Perfusion (SAAP)
Selective Aortic Arch Perfusion (SAAP) involves the use of a
large-lumen thoracic aortic balloon catheter to provide relatively
isolated perfusion to the heart and brain during cardiac arrest.
The perfusate is initially an exogenous oxygen carrier, such as
allogeneic blood or a hemoglobin-based oxygen carrier (HBOC),
but autologous blood can subsequently be used, if needed, in a
manner similar to extracorporeal life support (ECMO/ECLS).
SAAP was initially described in 1992 as a resuscitation
technique for treating nontraumatic/medical cardiac arrest with
the prehospital setting in mind. 2 Preclinical studies in models of
ventricular fibrillation demonstrated improved rates of return
of spontaneous circulation (ROSC) compared to standard
resuscitation therapies. The physiologic effects of SAAP were
characterized and perfusion parameters were optimized.
The potential for SAAP balloon hemorrhage control in trauma
and rapid volume repletion in hemorrhage-induced hypovolemia was
also recognized. In a 2001 preclinical report, SAAP with oxygenated
HBOC-201 showed consistent ROSC in a model of liver trauma with
exsanguination-induced cardiac arrest. 3 (See Figure 1.)
Subsequently, SAAP with allogeneic whole blood and red
blood cells, have been studied given the lack of a commercially
approved non-blood oxygen carrier. Translation into clinical
use is presently being pursued with clinical trial preparations
underway to investigate blood product and HBOC perfusates
in both hemorrhage-induced traumatic cardiac arrest and nontraumatic/medical cardiac arrest.
At the current time, data are limited for the use of SAAP and
REBOA in humans in cardiac arrest. In the future, this therapeutic
approach may play a vital role in the treatment of traumatic and
refractory cardiac arrest. ✚
Crews from the London
Ambulance Service work
through a simulation
with a patient requiring
occlusion of the aorta
(REBOA) to manage
pelvic, or lower extremity
PHOTO T WI T TER.COM/ TONYJO Y81
Figure 1: Selective aortic arch perfusion (SAAP) data from pig
studies shows potential3