Page 28 - Journal of Special Operations Medicine - Spring 2017

the balloon; in this setting, the increase in BP above the conditions permissive of migration. The risk of migra-
balloon could theoretically increase the rate of blood loss. tion can be partially overcome by securing the catheter
Although this consideration is important, in the emergent at multiple points outside the body by direct sutures
setting of impending cardiovascular collapse, concerns or central-venous access-line clips. Ideally, a dedicated
about this possible morbidity (similar to concerns about provider would manipulate balloon volumes during the
resuscitative thoracotomy) must be weighed against the transitions in inflation and ensure against migration.
lifesaving potential of the procedure. In this case series,
no patients had clinical evidence of bleeding sources that REBOA Discontinuation and Sheath Removal
would be exacerbated by aortic occlusion, but appropri- REBOA discontinuation requires careful consideration
ate judgment must be used in each instance of REBOA of patient resuscitation status and ability to tolerate
for patients with penetrating thoracic injuries. reperfusion. In our report, ongoing team resuscitation
facilitated balloon deflation over approximately 5 min-
Arterial Access utes in each instance. Deflation efforts should be coor-
The ability to effectively obtain arterial access is manda- dinated. Failure to control surgical sources of bleeding
tory to perform REBOA, but it may prove challenging or adequately resuscitate the patient before a controlled
in the setting of profound shock. A variety of methods deflation may lead to refractory hemodynamic collapse.
to facilitate common femoral artery access exist, in-
cluding palpation, the use of external landmarks, ultra- Sheath removal should be undertaken conscientiously.
sound-guided access, and open cut-down. Among these The 7F sheath permits the holding of pressure to facili-
options, ultrasound-assisted access affords an attractive tate adequate seal of the arteriotomy site. In the setting
balance among the concepts of minimal invasiveness, of coagulopathy, however, pressure alone may prove
relative speed, and safety. inadequate, and suture closure may be prudent. Con-
versely, the active infusion of whole blood, FFP, and
Our experience demonstrates the effectiveness of the TXA may promote local conditions that, when com-
handheld ultrasound VScan dual probe. The functional- bined with partial flow limitations around a sheath,
ity of the VScan is multifaceted—a key utility in austere may result in local thrombosis of the vessel or distal
settings. Ultrasound enables assessment for hemotho- limb embolic events. Extreme vigilance of limb perfu-
rax, pneumothorax, and hemoperitoneum, and also ef- sion after sheath removal is justified for this reason. In
fectively facilitates percutaneous transfemoral access. As the described cases, a thoughtful, distal extremity vascu-
illustrated in this report, a particularly important and lar examination and handheld ultrasound device were
vigilant maneuver for which VScan can be used is to used to facilitate this vigilance.
assess femoral artery patency and extremity perfusion
after removal of the REBOA sheath from the femoral Study Limitations
artery. Although less detailed than a formal duplex ul- Although it is illustrative of the potential utility of
trasound performed in a vascular laboratory, this level REBOA as a lifesaving intervention after combat trauma
of caution, using ever-improving ultrasound technology, and hemorrhagic shock, our present series has limita-
is one important way in which the risk for access-related tions. This initial experience included a small number
complications may be mitigated. of patients managed by a well-trained team. Any at-
tempt to extrapolate the success outlined in this report
Balloon Positioning to other care scenarios should undertaken with caution.
Following sheath placement, effective REBOA requires More data are needed to define optimal REBOA use in
appropriate balloon positioning for insufflation. The a variety of settings. Additionally, although the present
ER-REBOA catheter can be introduced via a 7Fr sheath Joint Trauma System Guidelines provide some guidance
and has calibrated external markings that facilitate use on REBOA in combat theater hospitals, there remain
of external anatomic measurements to determine the important issues that require study of out-of-hospital
14
depth required for introduction. Placement can be un- use, including the appropriately applicable sets, kits,
dertaken without the need for plain chest radiograph or and outfits; cost-benefit analysis; and barriers to doc-
advanced imaging. 4 trinal enactment. These needs highlight the importance
of official registries like the DoD Trauma Registry and
Distal migration of the balloon catheter can occur, as the AORTA registry in capturing data on episodes of
illustrated in one case in our series. A known phenom- REBOA.
enon, migration is most prone to occur during transi-
4
tion from complete occlusion to partial occlusion or Conclusion
deflation. As the balloon is deflated, the release of fric-
tional forces between the aortic wall and the balloon, This report documents use of REBOA in the contem-
combined with increased proximal pressure, creates porary management of combat casualties in a forward

6 Journal of Special Operations Medicine Volume 17, Edition 1/Spring 2017