Embolization in Splenic Trauma

Splenic preservation rates are improved for participants with high-grade splenic injuries
(defined as Grade III-V injuries by the AAST guidelines) when non-operative management is
supplemented by image-guided, trans-catheter splenic artery embolization (SAE). SAE is
currently the standard of care for hemodynamically stable participants with high-grade
splenic injuries. In proximal SAE (pSAE), the mid-splenic artery is embolized between the
origins of the dorsal pancreatic artery and pancreaticomagna artery with either VPs or coils.
This reduces the intra-splenic arterial pressure which allows the parenchyma time to heal.
Splenic perfusion is maintained via a collateral pathway consisting of flow from the splenic
artery proximal to the site of embolization through the smaller dorsal pancreatic artery to
the transverse pancreatic artery to the pancreaticomagna artery which then delivers a slower,
smaller amount of blood to the splenic artery distal to the site of embolization.
Additionally, collateral supply from the short gastric and gastroepiploic arteries helps to
protect the spleen from infarction and/or abscess formation.

pSAE is most often accomplished using either coils or VPs as the embolic agent, both of which
are FDA-approved and clinically-available. Coils have a long history of efficacy and safety
for embolization and are thus familiar embolic agents to most endovascular specialists.
Further, coils large enough to embolize the mid-splenic artery can be deployed through a
standard micro-catheter, which means they can be used in even the most tortuous splenic
arteries. However, multiple coils may need to be deployed in the same patient to achieve
hemostasis in the mid-splenic artery that may increase their overall cost, iodinated contrast
use, procedural time, and the radiation exposure to the participant and medical staff.
Additionally, given the high-flow nature of the splenic artery, even an appropriately sized
coil may migrate distally. A typical pSAE using coils will involve the deployment of one
helical coil followed by multiple packing coils until hemostasis is achieved. VPs attempt to
overcome the limitations of coils. For example, the deployment of a single VP can typically
provide hemostasis in the mid-splenic artery which theoretically reduces procedural time,
contrast load, and radiation exposure. Despite this, VPs are more expensive than coils on a
per unit basis and are usually less familiar devices to endovascular specialists. Another
drawback of VPs is that they cannot be deployed through a standard micro-catheter but rather
require the advancement of a larger, stiffer 0.035 inch system into the mid-splenic artery.
This may limit their use in very tortuous splenic arteries. Currently, the selection of
embolic agent for pSAE is primarily based on operator experience and preference. The embolic
efficacy, technical success, and cost of using coils compared to VPs has been evaluated in
other diseases; yet, to the best of our knowledge, these embolic agents have never been
compared for their use in pSAE, much less in a randomized, prospective fashion.

Inclusion Criteria:

- Patients presenting to UAB emergency room requiring embolization of the splenic artery