Overview

Definition: REBOA is an endovascular technique used in emergency settings to temporarily occlude the descending thoracic aorta, aiming to redistribute blood flow to vital organs (brain, heart) and increase proximal aortic pressure in patients with severe hemorrhagic shock.
Epidemiology:
-Hemorrhagic shock remains a leading cause of preventable death in trauma patients
-REBOA is indicated in non-compressible torso hemorrhage (NCTH) where conventional resuscitation has failed or is insufficient
-Its adoption is increasing globally, with growing evidence supporting its efficacy in select patient populations.
Clinical Significance:
-REBOA offers a temporizing measure to stabilize hemodynamically unstable patients with life-threatening bleeding from truncal injuries
-It buys time for definitive hemorrhage control, whether surgical or interventional radiology-based, thereby improving outcomes and reducing mortality in this critical patient group
-It is an adjunct to, not a replacement for, source control.

Indications And Contraindications

Indications:
-Hemodynamic instability (systolic blood pressure < 90 mmHg, requiring ongoing resuscitation) despite standard measures
-Presence of non-compressible torso hemorrhage
-Failure or delay in definitive hemorrhage control
-Patients unsuitable for immediate thoracotomy/laparotomy or requiring transport to definitive care.
Contraindications:
-Known severe aortic valve disease or insufficiency
-Severe pre-existing coagulopathy refractory to correction
-Penetrating cardiac injury
-Blunt cardiac injury with significant contusion
-Prolonged aortic occlusion time (>90 minutes, absolute contraindication due to ischemia)
-Patient refusal or lack of capacity
-Expected mortality too high even with REBOA
-Injury distal to the diaphragm with bleeding that can be controlled non-invasively.

Diagnostic Approach

History Taking:
-Focus on mechanism of injury (blunt vs
-penetrating)
-Time of injury
-Vital signs at presentation and response to initial resuscitation
-Previous medical history, especially cardiac and vascular conditions
-Duration of hypotension
-Pre-hospital interventions.
Physical Examination:
-Assess for signs of hemorrhagic shock: hypotension, tachycardia, altered mental status, pallor, cool extremities
-Examine for obvious external bleeding
-Palpate peripheral pulses (diminished or absent distal to occluded segment)
-Auscultate heart sounds for murmurs suggestive of aortic regurgitation.
Imaging And Investigations:
-FAST (Focused Assessment with Sonography for Trauma) and eFAST scans to identify intra-abdominal or thoracic free fluid
-CT angiography of chest, abdomen, and pelvis for source identification once stabilized
-Complete blood count (Hb, Hct), coagulation profile (PT, aPTT, INR), lactate, arterial blood gases (ABGs)
-Electrocardiogram (ECG) to assess for cardiac injury.
Differential Diagnosis:
-Other causes of shock in trauma: neurogenic shock, septic shock (late), cardiogenic shock
-Hemorrhage from extremities or pelvic fractures
-Aortic dissection (may be a cause or complication)
-Tamponade.

Reboa Procedure

Access And Insertion:
-Percutaneous femoral artery access is most common, typically using a Seldinger technique with a guidewire
-A 5F-7F sheath is inserted
-A dedicated REBOA catheter with an inflatable balloon is advanced under fluoroscopic guidance.
Balloon Placement:
-The balloon is typically positioned in Zone I (distal to left subclavian artery, proximal to celiac artery) for truncal hemorrhage control
-Zone II (distal to left subclavian, proximal to renal arteries) may be used for lower abdominal injuries
-Accurate placement is crucial to avoid compromising cerebral or cardiac circulation.
Inflation And Monitoring:
-The balloon is inflated with sterile saline until adequate proximal aortic pressure is achieved (target systolic BP 100-120 mmHg) and distal pulses become absent
-Inflation should be intermittent (e.g., 15 minutes on, 5 minutes off) to minimize ischemic complications
-Continuous hemodynamic monitoring is essential.
Removal And Definitive Care:
-REBOA is a temporizing measure
-Definitive hemorrhage control (surgery or IR embolization) should be performed as soon as feasible
-Balloon removal is done after source control is achieved or when patient is hemodynamically stable
-Post-removal monitoring for complications is vital.

Complications

Early Complications:
-Ischemia and reperfusion injury to lower extremities, kidneys, bowel, and spinal cord (paraplegia)
-Aortic dissection or rupture
-Catheter-related thrombosis or embolization
-Bleeding at access site
-Myocardial ischemia or stunning
-Acute kidney injury.
Late Complications:
-Aortic aneurysm formation or pseudoaneurysm at the site of insertion or dissection
-Chronic limb ischemia
-Organ dysfunction due to prolonged ischemia-reperfusion
-Spinal cord injury leading to paraplegia (most feared).
Prevention Strategies:
-Strict adherence to indications and contraindications
-Minimize occlusion time and use intermittent inflation
-Accurate balloon placement
-Prompt definitive hemorrhage control
-Meticulous surgical technique for access and closure
-Careful patient selection and monitoring
-Utilize advanced imaging when available
-Consider anticoagulation judiciously if no contraindication.

Prognosis

Factors Affecting Prognosis: Severity of hemorrhage, time to REBOA placement, duration of occlusion, success of definitive hemorrhage control, pre-existing comorbidities, development of complications (especially spinal cord ischemia), and overall patient physiology.
Outcomes:
-When used appropriately as a temporizing measure, REBOA can significantly improve survival rates in patients with otherwise unsalvageable hemorrhagic shock
-It allows for transfer to definitive care and successful hemorrhage control
-However, significant morbidity can still occur if complications arise.
Follow Up:
-Close hemodynamic monitoring post-removal
-Serial assessment for signs of limb ischemia, abdominal compartment syndrome, or end-organ dysfunction
-Neurovascular checks are paramount
-Imaging of the aorta (e.g., CT angiography) may be required in the subsequent days to weeks to assess for late vascular complications.

Key Points

Exam Focus:
-REBOA is a temporizing endovascular technique for non-compressible torso hemorrhage
-Zone I occlusion for truncal injuries is standard
-Minimize occlusion time
-Complications include spinal cord ischemia and lower limb ischemia
-Definitive hemorrhage control is essential.
Clinical Pearls:
-Think REBOA when conventional resuscitation fails in a bleeding patient
-Always have a plan for definitive source control before initiating REBOA
-Monitor proximal and distal pulses closely
-Intermittent inflation is crucial to prevent ischemia
-The goal is time, not cure.
Common Mistakes:
-Using REBOA without a clear indication or when definitive care can be immediately provided
-Prolonged, continuous occlusion time
-Incorrect balloon placement leading to neurological deficits or inadequate resuscitation
-Failure to have a plan for source control
-Overlooking significant aortic pathology as a contraindication.