Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) is a specialized medical procedure used in emergency settings to control catastrophic internal bleeding. This technique employs a long, flexible catheter with an inflatable balloon at its tip, designed to be placed within the body’s largest artery, the aorta. REBOA provides temporary control over severe hemorrhage that cannot be stopped by external pressure, often called non-compressible bleeding. By physically blocking the flow of blood, the device helps maintain circulation to the heart and brain, buying time for the patient to reach the operating room for definitive surgical repair.
The Mechanism of Aortic Occlusion
The REBOA device achieves hemorrhage control through a minimally invasive, endovascular approach. The procedure begins with the insertion of a catheter, typically through the common femoral artery in the groin, using a technique similar to standard arterial line placement. The catheter is then threaded backward, or retrograde, up the iliac artery and into the aorta.
Once positioned, the balloon at the tip is inflated, causing a complete or partial blockage of blood flow in the aorta. This physical occlusion creates a temporary internal tourniquet, stopping blood from reaching the bleeding site below the balloon. This action stabilizes the patient’s blood pressure by reducing blood loss and redirecting flow to the upper body, specifically the coronary and cerebral arteries.
The precise positioning of the balloon is determined by the injury location, utilizing three anatomical segments known as REBOA Zones. Zone 1, the descending thoracic aorta, is used for major bleeding within the chest or upper abdomen, such as from the liver or spleen. Zone 3, positioned in the infrarenal abdominal aorta, is reserved for hemorrhage originating in the pelvis or groin, often due to severe pelvic fractures.
The distinction between these zones is important because placement dictates which organs lose blood flow. Zone 2, situated between the arteries supplying the celiac trunk and the lowest renal artery, is generally avoided. Inflation in Zone 2 carries a significant risk of obstructing blood flow to vital abdominal organs.
Critical Situations Requiring REBOA
REBOA is reserved for patients suffering from life-threatening hemorrhagic shock due to non-compressible torso hemorrhage. This bleeding originates deep within the chest, abdomen, or pelvis, making it impossible to apply direct pressure. These scenarios often arise from high-energy trauma, such as car accidents or falls, or from penetrating injuries.
A common indication for REBOA is massive internal bleeding from a severe pelvic fracture. The pelvis is highly vascular, and fractures can cause rapid hemorrhage difficult to manage externally. Occluding the aorta in Zone 3 temporarily halts blood flow to the lower extremities and damaged pelvic vessels, stabilizing the patient’s circulation.
Major abdominal trauma involving solid organs like the liver or spleen frequently necessitates a Zone 1 REBOA deployment. Rapid blood loss into the abdominal cavity can quickly lead to cardiovascular collapse. Inflating the balloon in the chest prevents blood from traveling down and feeding the injury, isolating the bleeding site from the main circulatory volume.
REBOA serves as a rapid bridge to definitive care. Its success is measured by its capacity to stabilize a patient near death, increasing blood pressure to a survivable level. This temporary stabilization provides the window needed to safely transport the patient to a surgical suite for permanent repair.
REBOA vs. Traditional Surgical Intervention
Before REBOA, the standard method for rapid aortic occlusion in the emergency department was Emergency Department Thoracotomy (EDT). This surgical procedure required a large incision in the chest to manually clamp the aorta, a process known as aortic cross-clamping. EDT is complex, carries substantial risks, and is highly invasive.
REBOA offers a less invasive alternative for temporary hemorrhage control below the diaphragm. Instead of open-chest surgery, REBOA uses a small puncture in the groin, allowing the trauma team to control bleeding with a catheter. This difference in invasiveness often results in a faster procedure time, which is crucial when a patient is hemorrhaging rapidly.
REBOA deployment may be associated with a higher mean systolic blood pressure after occlusion compared to surgical cross-clamping. Maintaining better pressure enhances perfusion to the heart and brain, organs sensitive to a lack of oxygenated blood. REBOA is a temporary measure that creates the necessary physiological conditions for the patient to endure transfer and definitive operation.
The endovascular placement causes less physiological stress on the compromised patient than the trauma of an open thoracotomy. EDT remains necessary for specific indications, such as suspected bleeding within the chest or the need for open-chest cardiac massage. However, REBOA provides a modern, less destructive method to achieve aortic occlusion for injuries below the diaphragm.
Potential Risks and Time Constraints
While REBOA is life-saving, the procedure carries substantial risks inherent in stopping blood flow to a large portion of the body. The most significant limitation is the risk of ischemia, or tissue death, in the organs and limbs below the occlusion. Since the balloon prevents blood flow, tissues distal to the occlusion are deprived of necessary oxygen and nutrients.
Medical protocols impose strict time limits on how long the balloon can remain inflated to mitigate this damage. For a Zone 1 occlusion, which affects the entire lower body and abdominal organs, the maximum inflation time is often around 30 minutes. In Zone 3, which spares the abdominal organs, the tolerable time may extend closer to 60 minutes, though survival decreases with prolonged times.
A major risk is reperfusion injury, which occurs when blood flow is restored after a period of blockage. The sudden return of blood carries accumulated acidic waste products and inflammatory mediators from the ischemic tissues back into the main circulation. This influx can potentially lead to cardiac arrest or multi-organ failure, with acute kidney injury being a frequently documented systemic complication.
Local complications at the insertion site are also a concern, as the catheter requires the placement of a large access sheath in the femoral artery. Vascular access complications include arterial dissection, pseudoaneurysm formation, or the development of blood clots. The procedure is a race against time, requiring rapid deployment and immediate transfer to definitive care to avoid these severe, time-dependent complications.