The management of major trauma has a long history of failures found along a road of good intention. From Military Anti-Shock Trousers (MAST) to aggressive crystalloid administration, we’ve seen management strategies come and go over the years, after the reality of the practice didn’t measure up to the expectation of improved outcomes.
Today, we have several novel concepts being implemented across the world to try to move the needle for trauma resuscitation. Tranexamic acid (TXA), blood product administration, and simple (finger) thoracostomy are a few of the advances that seem to be gaining interest in EMS. Although these developments are still “state of the art” practice in EMS, many are wondering what the next stop is on the road to trauma management.
The next stop may be resuscitative endovascular balloon occlusion of the aorta (REBOA) for hemorrhagic shock with uncontrolled abdominal, pelvic, or lower extremity bleeding.
What Is REBOA?
The procedure involves first performing a chest X-ray to ensure that there’s no widened mediastinum indicating thoracic aortic dissection. Then a 7 cm French sheath is inserted into the femoral artery through ultrasound-guided percutaneous technique or cut-down. The REBOA catheter is then measured using landmarks for Zone 1 insertion to address abdominal hemorrhage, or Zone 3 insertion to address isolated pelvis or lower extremity hemorrhage.
The balloon is introduced to the desired length and a second chest X-ray is performed to confirm appropriate positioning. Finally, the balloon is filled with saline to occlude the aorta and stop distal blood flow.
Though trials are ongoing, many believe that this procedure is the therapeutic equivalent of cross-clamping the aorta during emergency thoracotomy. However, with innovation comes controversy–and there’s no shortage of controversy about this procedure.
Trauma surgeons have claimed this as a surgeon-only procedure, with a caveat that emergency medicine (EM) physicians could also perform it if they have additional training and experience in critical care. Much to the chagrin of the EM and EMS community, this position was endorsed by the American College of Emergency Physicians (ACEP).
Even though the more invasive procedure of emergency thoracotomy is an essential skill for training and board certification, this less-invasive procedure is somehow too complicated. This dispute is ongoing, but unlike blood products, TXA, and simple thoracostomy, it hasn’t cleared the hurdle of entry into EM with REBOA “¦ Yet!
Challenges & Concerns
Although I disagree with the ACEP’s position statement, I do agree that there are a number of challenges and concerns regarding REBOA and its practical application in EM and EMS.
First, we’re not yet sure how long the balloon can be inflated before catastrophic ischemia and the associated cascade of metabolic disasters occur.
Second, we’re not yet sure if the procedure should be aimed at complete occlusion or partial occlusion, which would effectively lower the blood pressure distal to the balloon to allow for stemming of the hemorrhage and perhaps clot development to occur.
Third, correct positioning of the balloon should be confirmed with imaging prior to inflation, which may be a challenge in the field. This is an essential step to ensure that the balloon is in the appropriate zone of the aorta. If the balloon is too high or too low, it could rupture the aorta or obstruct the vasculature of the abdominal organs, which could be fatal for the patient.
Finally, the patient will need immediate access to a surgeon or interventional radiologist to definitively manage the source of the bleeding. Of course, we’ll have trouble defining “immediate” in this context. That won’t happen until we have answers to the first three questions.
These challenges are significant in the critical and perimortem trauma patient, however, they seem much less controversial in traumatic cardiac arrest (TCA). The reason behind this is that our current practice of rushing TCA patients to the trauma center yields abysmal outcomes, with a survival rate of approximately 1%. If you’re across the street from the Level 1 facility, that’s probably still the best answer. If you’re farther away, another strategy may be more appropriate.
A Pit Crew Approach for Trauma
Just as we’ve found with medical cardiac arrest, TCA may be better managed by bringing the resources of the ED to the patient–rather than bringing the patient to the ED. Adherence to this antiquated strategy means we’ve missed out on opportunities to save the lives of our most severely injured patients. It’s time to turn this strategy on its head.
REBOA may turn out to be a critical component of a pit crew approach to traumatic cardiac arrest. Those components include high-quality CPR, oxygenation, and ventilation, like the traditional pit crew approach for medical cardiac arrest.
It would include whole blood administration, which has shown to be logistically feasible in the ground EMS setting. It would also include simple thoracostomy to address tension pneumothorax, and perhaps tube thoracostomy to manage tension hemothorax. It would also likely include ultrasound-guided pericardiocentesis and REBOA as potentially less invasive procedures to substitute for an ED thoracotomy.
Although the entire bundle of care approach to TCA may be some years out, it’s critical that we continue to challenge the status quo.
As we see increased field response of EM physicians across the country, we’ll also see increased advocacy for bringing advanced procedures like REBOA to the field and, subsequently, move them into the field for paramedics so that we can finally move the needle on survival from out-of-hospital TCA.