Thoracic Trauma — Non-Aortic Embolization

1

Indications & Contraindications

Bleeding sources, hemothorax thresholds, surgical vs IR triage

▾

Indications

Intercostal artery hemorrhage — rib fractures (blunt), penetrating chest wall injury, iatrogenic (chest tube / thoracentesis / biopsy)
Internal mammary artery (IMA) injury — sternal fracture, penetrating parasternal trauma, central line placement complication
Bronchial artery hemorrhage — traumatic hemoptysis; massive hemoptysis >100 mL/h or >500 mL/24 h
Subclavian / axillary artery injury — pseudoaneurysm, arteriovenous fistula, focal laceration amenable to endovascular repair
Chest wall bleeding — lateral thoracic, phrenic artery, or other chest wall vessel injury with active extravasation on CTA
Hemothorax with ongoing chest tube output — >200 mL/h for 2–4 h or >1,500 mL initial output indicating arterial source amenable to embolization

Contraindications

Massive hemothorax requiring thoracotomy — hemodynamically unstable unresponsive to resuscitation; ATLS criteria: >1,500 mL initial drainage or >250 mL/h for 3 consecutive hours
Cardiac tamponade / hemopericardium — mandate surgical intervention, not embolization
Hemodynamic instability refractory to resuscitation — patient not stable enough for angiography suite
Total or subtotal vessel transection — axillosubclavian injuries with long-segment disruption are contraindicated for endovascular repair
Relative: venous or pulmonary parenchymal bleeding source (will not respond to arterial embolization — consider surgical management)

Hemothorax Triage Guide

Volume / Output	Classification	Management
<400 mL	Minimal	Conservative — serial CXR every 4–6 h then daily
400–1,000 mL	Medium	Chest tube drainage; CTA to identify arterial source; consider embolization
>200 mL/h × 2–4 h	Ongoing arterial bleed	Emergent angiography and embolization
>1,500 mL initial	Massive	Thoracotomy — NOT embolization

2

Pre-Procedure Planning

CTA review, resuscitation, surgical backup

▾

Imaging & Labs

CTA chest — identify bleeding source: arterial blush / extravasation, pseudoaneurysm, vessel cutoff; localize to intercostal level, IMA, bronchial, or subclavian/axillary territory
Multidetector CT with arterial phase — coronal/sagittal reformats to map intercostal artery anatomy and identify collateral pathways
Labs: CBC, PT/INR, BMP, type & crossmatch; monitor serial hemoglobin
Chest X-ray at baseline — assess hemothorax volume, lung aeration, mediastinal shift

Patient Preparation

Chest tube in place — monitor hourly output; ensures continued drainage during angiography
Massive transfusion protocol (MTP) activated if indicated — 1:1:1 PRBC:FFP:platelets
Cardiothoracic surgery consultation — on standby for conversion to thoracotomy if embolization fails or patient decompensates
Large-bore IV access ×2; arterial line for continuous BP monitoring
Airway secured if hemoptysis (bronchial bleeding) — single-lumen ETT or double-lumen for lung isolation

CTA reviewed. Active extravasation identified and localized. Bleeding vessel(s) mapped. Intercostal level(s), IMA, bronchial, or subclavian territory determined.

Chest tube in place and functioning. Hourly output being monitored. Baseline drainage volume documented.

Resuscitation initiated. MTP activated if needed. Blood products available. Hemoglobin and coagulation trending.

Cardiothoracic surgery notified. On standby for operative backup. Thoracotomy tray available.

Hemothorax volume assessed. If >1,500 mL initial output → thoracotomy, not embolization. Confirmed embolization is appropriate.

Airway plan for bronchial bleeding. Anesthesia aware; lung isolation strategy discussed if hemoptysis is the presentation.

3

Relevant Anatomy

Intercostal arteries, IMA, bronchial arteries, subclavian/axillary branches, spinal artery concern

▾

Intercostal Arteries

Posterior intercostal arteries arise from the posterior aorta (T3–T11); T1–T2 from costocervical trunk (subclavian branch)
Course along the inferior margin of each rib in the costal groove (neurovascular bundle: vein, artery, nerve from superior to inferior)
Spinal branch — each posterior intercostal artery gives off a dorsal branch with a spinal (radicular) artery; the artery of Adamkiewicz (great anterior radiculomedullary artery) most commonly arises from a left intercostal artery at T9–T12
Rich collateral supply between anterior and posterior intercostal systems — may require embolization of levels above and below the injury

Internal Mammary Artery (IMA)

Originates from the subclavian artery (inferior surface)
Descends along the pleural surface, lateral to the sternum
Vulnerable to sternal fractures and penetrating parasternal trauma
Average blood flow ~150 mL/min — can rapidly produce life-threatening hemorrhage
Expendable vessel — rich mediastinal collateral network prevents tissue infarction after embolization

Bronchial Arteries

Typically originate from the descending aorta at T5–T6 vertebral level
Anomalous origins exist outside T5–T6 — must search for variant anatomy on CTA and aortography
Responsible for ~90% of hemoptysis cases (most commonly chronic disease, but also traumatic)
Same spinal artery concern as intercostal embolization — bronchial arteries may give rise to spinal branches

Subclavian / Axillary Arteries

Subclavian artery branches: vertebral, IMA, thyrocervical trunk, costocervical trunk
Axillary artery: continuation of subclavian beyond first rib; branches include thoracoacromial, lateral thoracic, subscapular
3–9% of all vascular injuries; mortality up to 40%
Proximity to brachial plexus — neurovascular injury risk with both surgical and endovascular approaches
40–50% of axillosubclavian injuries treatable with endovascular interventions (covered stents)

4

Technique

Access, catheter selection, embolics, covered stent placement

▾

1

Arterial Access

Common femoral artery (CFA) access, typically right. 5F sheath. For subclavian/axillary interventions, ipsilateral brachial or CFA approach depending on injury location and planned intervention. Ensure hemostasis plan (manual compression or closure device) given likely coagulopathy.

2

Catheter Selection & Aortography

Intercostal / bronchial selection: 5F Cobra 2 or Mikaelson catheter for selective intercostal and bronchial artery catheterization from the descending aorta. Consider flush aortogram to map anatomy if CTA findings are equivocal. IMA: 5F internal mammary catheter or Cobra from ipsilateral subclavian. Subclavian/axillary: 5F diagnostic catheter for arteriography followed by stiff guidewire exchange for intervention.

3

Selective Angiography

Selective angiogram of the involved territory guided by CTA findings. For intercostal arteries: catheterize at the level of injury and one level above and below. Look for: active extravasation, pseudoaneurysm, hypervascularity, tortuous/enlarged arteries (>3 mm). CRITICAL: Before embolizing any intercostal artery, identify the spinal branch and look for the artery of Adamkiewicz. Use DSA with adequate magnification.

4

Embolization — Intercostal & IMA

Intercostal PSA / active bleed: Microcoils preferred (detachable fibered coils) — allows precise placement distal and proximal to the injury site (front door–back door technique to address retrograde collateral flow). Avoid particles to minimize reflux risk into spinal artery. IMA injury: Microcoil embolization; pushable or detachable coils; Gelfoam slurry as adjunct. IMA is expendable — complete occlusion acceptable. May need to embolize levels above and below the injured intercostal due to rich collateral supply.

5

Embolization — Bronchial Artery

For bronchial artery hemorrhage (traumatic hemoptysis): Gelfoam pledgets or calibrated PVA particles (300–500 µm) are most commonly used. Microspheres also acceptable (less clumping than PVA). Avoid very small particles (<300 µm) to reduce nontarget embolization risk. Same spinal artery precaution as intercostal embolization. Superselective catheterization with microcatheter before embolization.

6

Covered Stent — Subclavian / Axillary

For subclavian/axillary artery injury with appropriate anatomy (focal laceration, pseudoaneurysm, AV fistula): covered stent graft placement to exclude the injury while maintaining arterial patency. Self-expanding covered stent sized to vessel diameter. Contraindicated if long-segment disruption, total transection, or insufficient proximal/distal fixation points. Guidewire must cross the lesion — failure to cross mandates surgical repair.

7

Completion Angiography

Post-embolization or post-stent arteriogram to confirm: cessation of extravasation, occlusion of pseudoaneurysm, preserved flow in parent vessel (for stent cases). Evaluate collateral reconstitution of the bleed — if persistent filling, embolize additional feeding vessels. Check adjacent intercostal levels.

Community Cards

Browse Card Library →

Sign in to view and create community cards

5

Key Landmarks

Arterial origins, vertebral levels, catheter targets

▾

Intercostal Artery Origins

Arise from the posterior aorta at each vertebral level (T3–T11)
T1–T2 from costocervical trunk (subclavian branch)
Catheter directed posterolaterally from descending aorta
Artery of Adamkiewicz: most commonly left T9–T12

IMA Origin

Arises from the inferior surface of the subclavian artery, medial to the thyrocervical trunk
Descends 1–2 cm lateral to the sternal border
Bifurcates into musculophrenic and superior epigastric arteries at ~6th intercostal space

Bronchial Artery Level

Typically originate from descending aorta at T5–T6 vertebral level
Variant origins above or below T5–T6 common — search on aortogram
Look for right intercostobronchial trunk (ICBT) — shared origin with intercostal artery

6

Troubleshooting

Intraoperative problems and solutions

▾

Critical

Spinal Artery Identified Arising from Intercostal Artery

Do NOT embolize with particles or distally in that intercostal artery. Use coils placed proximal and distal to the spinal branch origin to isolate the bleeding segment while preserving spinal supply (sandwich technique). If the spinal branch cannot be safely spared, consider superselective microcatheter positioning beyond the spinal branch takeoff before embolizing. If not technically feasible, abort embolization of that level and consult surgery. Same principle applies to bronchial artery embolization.

Multiple Rib Fractures

Bleeding from Multiple Intercostal Levels

May need to catheterize and embolize multiple intercostal arteries. Systematically work through each level identified on CTA. Check one level above and below each fracture site. Use the front door–back door embolization technique at each level to prevent retrograde collateral reconstitution. Anticipate prolonged procedure time; communicate with anesthesia and trauma team.

Ongoing Hemothorax Despite Embolization

Persistent Chest Tube Output After Technically Successful Embolization

Consider venous bleeding source (intercostal vein, pulmonary vein) or pulmonary parenchymal injury — these will not respond to arterial embolization. Reassess with CTA if patient stable. If venous or parenchymal source confirmed, surgical management (VATS or thoracotomy) is required. Communicate with cardiothoracic surgery team immediately.

Vasospasm

Catheter-Induced Spasm of Small Intercostal or Bronchial Artery

Administer nitroglycerin 100–200 mcg intra-arterial through the catheter. Wait 2–3 minutes for resolution. If spasm persists, withdraw catheter to the aorta and re-engage gently. Do not mistake vasospasm for successful embolization — spasm will resolve and bleeding may recur. Some patients may have persistent spasm even after nitroglycerin.

Cannot Cross Lesion

Guidewire Fails to Cross Subclavian/Axillary Injury

Inability to pass a guidewire across a subclavian or axillary lesion is a contraindication to endovascular therapy. Convert to surgical management. Communicate findings to the surgical team and facilitate operative planning based on angiographic roadmap.

7

Complications

Recognized risks and management

▾

Serious Complications

Spinal cord ischemia / paraplegia — reflux of embolic material into radicular artery (artery of Adamkiewicz) supplying the anterior spinal artery; mitigated by using coils (not particles), superselective positioning, and identifying spinal branches before embolizing
Continued hemothorax — venous or pulmonary parenchymal source not addressed by arterial embolization; requires surgical intervention
Non-target embolization — embolic material reaching unintended territories; particularly concerning in bronchial artery embolization (esophageal necrosis, bronchial wall ischemia)
Stent thrombosis / migration — covered stent in subclavian/axillary territory; may require antiplatelet therapy or surgical revision

Other Complications

Chest wall necrosis — ischemia from extensive intercostal embolization; rare due to collateral supply
Access site complications — hematoma, pseudoaneurysm at CFA; higher risk in coagulopathic trauma patients
Rebleeding — recurrence rates of 10–55% for bronchial artery embolization; intercostal rebleeding from collateral reconstitution if front door–back door technique not used
Post-embolization chest pain / dysphagia — particularly after bronchial artery embolization; usually self-limited

8

Pearls & Pitfalls

Critical safety points, clinical decision-making, technical tips

▾

✦

Same spinal artery concern as BAE. Always identify the spinal branch before embolizing any intercostal or bronchial artery. The artery of Adamkiewicz (typically left T9–T12) supplies the anterior spinal artery — reflux of embolic material causes devastating spinal cord infarction.

✦

IMA injury: think sternal fracture or central line. IMA hemorrhage is commonly associated with sternal fractures from blunt deceleration injuries or iatrogenic injury from central venous catheter placement. The IMA is expendable — embolize without concern for downstream ischemia.

✦

Hemothorax >1,500 mL initial = thoracotomy, not embolization. ATLS guidelines are clear: massive hemothorax with >1,500 mL initial drainage mandates surgical management. Do not delay thoracotomy for angiography in this setting.

✦

Embolize above and below. Intercostal arteries have rich collateral supply between the anterior (IMA-fed) and posterior (aortic) systems. Embolizing only the bleeding level may fail — always use the front door–back door technique and consider embolizing one level above and below the injury.

✦

Coils for intercostals, particles for bronchials. Use coils for intercostal PSA and IMA injury (precise, no reflux risk into spinal artery). Use Gelfoam/PVA/microspheres for bronchial artery bleeding (need to embolize diffuse microvasculature). Avoid particles in intercostal arteries with spinal branches.

!

Do not mistake vasospasm for successful embolization. Catheter-induced spasm of small intercostal arteries can mimic cessation of flow. Spasm will resolve and bleeding will recur. Administer intra-arterial nitroglycerin and wait before concluding the procedure.

!

Persistent hemothorax after embolization = think venous. Arterial embolization will not address intercostal vein, pulmonary vein, or lung parenchymal bleeding. If chest tube output persists after technically successful embolization, escalate to surgery.

!

Delayed IMA bleeding. IMA may retract and temporarily achieve hemostasis from arterial spasm and hypotension after complete transection. Delayed hemorrhage has been documented from 4 hours to 4 weeks post-trauma — maintain high suspicion even with initial hemostasis.

9

References & Resources

Primary sources and related procedures

▾

Key Outcomes

Intercostal artery TAE: 85–100% procedural success rate; 21–37.5% 30-day mortality (reflects severity of underlying trauma)
IMA embolization: 91.6% success rate vs 66% for surgical ligation
Bronchial artery embolization: >90% technical success, 73–99% clinical success; 10–55% recurrence requiring retreatment
Axillosubclavian covered stent: shorter operative time, less blood loss, comparable 1-year patency vs open repair

Primary References

Higgins MCSS, Shi J, Bader M, Kohanteb PA, Brahmbhatt TS. Role of interventional radiology in the management of non-aortic thoracic trauma. Semin Intervent Radiol. 2022;39(3):312–328. DOI: 10.1055/s-0042-1753482
Stampfl U, Sommer CM, Engel H, et al. Intercostal artery embolization for traumatic bleeding: review of indications, technique, and outcomes. Cardiovasc Intervent Radiol.
Tamburini N, Fiorelli A, Fiorentino M, et al. Transarterial embolization of intercostal arteries for refractory hemothorax. J Thorac Dis.
ATLS Subcommittee, American College of Surgeons Committee on Trauma. Advanced Trauma Life Support. 10th ed. Chicago, IL: ACS; 2018.
Carrillo EH, Heniford BT, Senler SO, et al. Embolization therapy as an alternative to thoracotomy in vascular injuries of the chest wall. Am Surg. 1998;64(12):1142–1148.