“Beyond saving lives”: Current perspectives of interventional radiology in trauma

Table 1 Embolizing agents used in traumatic injuries

Embolizing agent	Indications	Advantages	Demerits
Permanent
Coil (covered with thrombogenic fibers) (Size of coil should be 20%-30% more than the target vessel size)	Active contrast extravasation Pseudoaneurysm	Rapid and effective control of bleeding Agent of choice when site of bleeding can be approached superselectively Relatively cheap (standard coils)	Reduced effectiveness in coagulopathy which hampers effective thrombosis Limited utility when target site can not be selectively approached
Non-absorbable particles (e.g., Polyvinyl alcohol)	Injury to terminal vessels	Permanent control of bleeding Adjunct to gelfoam	Tendency to clump and aggregate at the catheter site leading to proximal embolization, catheter block Non targeted embolization due to small size Tissue necrosis No added benefit over gelfoam, incurs additional cost
Liquid embolic agent [e.g., glue(N-butyl cyanoacrylate)]	As an alternative to coil especially in rebleeding	Rapid control of bleeding in hemodynamically unstable patients	Expertise for controlled delivery at target site Propensity for non targeted distal embolization leading to infarct or necrosis Rarely glue embolization of pulmonary circulation
Amplatzer vascular plug (AGA Medical Corporation, Plymouth, MN, United States) Available in various sizes	Large caliber vessel or large AVF (large size plug)	Single device (mesh shaped metal coil): Deployed with much greater accuracy and replaces the need of multiple coils	Costly Less beneficial in cases of distal vascular injury with good collateralization as it is deployed in proximal larger branch
Temporary
Gelatin sponge (CuraMedical, Assendelft, the Netherlands) Either in the form of pledgets (cut from gelfoam sheet) or slurry (non- ionic iodinated contrast mixed with gelfoam)	Cornerstone of IR in trauma: Controls majority of haemorrhage	Rapid, effective temporary occlusion of bleeding site Easily available and cheap Can be easily refashioned to the size of target artery	Non-targeted embolization to proximal branches can occur in case of rapid injection Resorbed after 3 wk: Potential risk of delayed haemorrhage Reduced effectiveness in impaired hemostasis Small risk of infection due to entrapped air during preparation
Autologous clot	Nonselective and rapid control of haemorrhage	Easy availability No cost	Clot dissolution in cases of coagulopathy and hemodilution
Starch microparticles	Usually complete reperfusion after 60 min, less tissue damage	Temporary occlusion is usually complete Uniform distribution	Allergic, non-target embolization

Table 2 Embolizing agents precluded in traumatic injuries[6-10]

Embolizing agent	Reason
Powdered form gelatin sponge	Obliteration of small caliber vessels: May lead to infarction or abscess Large caliber vessels: Risk of rebleeding due to potential collateralization from neighboring undamaged parenchyma
Non absorbable particles of small size (e.g., polyvinyl alcohol), liquid embolic agents (glue)	Difficult to handle: Striking balance between selective embolization vs optimizing end point of embolization an issue Non-targeted embolization: Irreversible unwanted tissue damage
Alcohol	Extensive tissue necrosis Difficult to the handle while delivering at the target site

Table 3 Endovascular interventions in renal artery injury[27]

Vascular injury
Site and type of injury	Endovascular management	Comments
Main renal artery-dissection, laceration, contrast extravasation	Stent graft	Preserves flow across the site of injury if negotiated safely and successfully
Main renal artery occlusion	Intra-arterial thrombolysis using urokinase or tissue plasminogen activator	Salvages kidney if administered within 6 h of injury
Intra-renal haemorrhage or pseudoaneurysm	Superselective embolization via microcatheter system and microcoils	Targeted embolization: Preserves functioning renal parenchyma
Arterio-venous or arterio-calyceal fistula	Embolization just proximal to fistulous site	Targeted embolization: Preserves functioning renal parenchyma

Table 4 Permanent embolization in peripheral vascular injury[4]

Indication	Contraindication
Non vital branches	Major vessels like axillary, brachial, superficial femoral and popliteal arteries due to risk of critical limb ischemia
Proximal non-axial branches, e.g., profunda brachii and profunda femoris