Study population
We retrospectively reviewed all patients referred to our hospital for MB who were treated by TAE, based on clinical decisions in emergency and computed tomography (CT) images, between January 2010 and March 2021. MB was defined as mesenteric hematoma and contrast extravasation and/or pseudoaneurysm visible on pre-operative CT scan.
The inclusion criteria were as follows: (1) age 18 or over (2) patients suffering from acute arterial isolated MB and treated by TAE (3) active bleeding and/or pseudoaneurym on preoperative CT scan. Our exclusion criteria were (1) patients with no available pre-operative CT scan, (2) patients without available biological data, (3) patients with isolated retroperitoneal bleeding (4) patients with both mesenteric and gastro intestinal bleeding.
Clinical data
We retrospectively reviewed clinical presentations at baseline, CT findings, cause of bleeding details of the embolization procedure, such as the angiographic findings and embolic materials used, procedure-related complications, and outcomes after TAE, including technical and clinical success and 30-day mortality rates. Patients who met one of the following criteria at patients’ initial presentation were classified in the coagulopathy group: international normalized ratio ≥ 1.5, platelet count less than 80G/L, and prothrombin ratio ≤ 50%. Hemodynamic instability was defined as PAS < 90 mmHg and/or a decreased in systolic pressure despite pharmacological support.
All patients underwent an abdominal CT scan (SOMATOM SENSATION before September and SOMATOM Siemens AG, Medical solutions, Erlangen, Germany). An unenhanced CT scan was first performed, followed by at least arterial and parenchymal phase and sometimes delayed phase. Patients received ≥90 ml contrast medium (Xenetix 350®, Guerbet, Villepinte, France) with a flow rate ≥ 3 ml/s.
Angiography and embolization procedure
Angiographies and embolizations were performed by 8 interventional radiologists whom experience in TAE ranged from 2 to 30 years, after decisions made with the surgeon and the clinician. After local anaesthesia with 5 ml of Lidocaïne, the most common approach was through the right femoral artery. Celiac, superior mesenteric, and/or inferior mesenteric angiograms were performed to determine the focus of mesenteric injury using a 4F catheter and a hydrophilic guidewire (Terumo, Tokyo, Japan). All procedures were performed using fluoroscopy and/or roadmap technique. Supraselective catheterism was systematically performed, using a 2.7F microcatheter (Progreat, Terumo, Tokyo, Japan). The choice of embolic agent depended on the presence of pseudoaneurysm and/or active bleeding, the presence of collaterals, the location of the feeding artery, the clinical condition of the patient, and the habits of the physician. Embolization as close as possible to the point of bleeding was routinely performed to limit the risk of bowel ischemia. In case of visible collaterals, the coil trapping embolization technique using coils was performed. In case of embolization with NBCA, the microcatheter was flushed with 5% dextrose solution followed by injection of NBCA in a solution of ethiodized oil (Lipiodol, Guerbet, Villepinte, France) with 1/3 proportion. Embolizations were performed using fibered microcoils (Interlock Boston scientific, MA, USA), N-butyl-2-cyanoacrylate (NBCA)(Glubran)(Glubran2®, GEM, Viareggio, Italy), gelatin sponge (Gelitaspon®, Gelita Medical GmbH, Eberbach, Germany) or microparticles (Embosphere® Microspheres, BioSphere Medical, Rockland, MA). After the procedure, complete angiograms were performed to confirm that bleeding had been successfully controlled.
Patient follow-up
After TAE, all patients were monitored closely for clinical signs and symptoms that were potentially suggestive of ischemic complication or recurrent bleeding until discharge or death. These clinical findings were supplemented by laboratory studies. The long-term outcome of the patients, specifically incidence of rebleeding, mortality and procedure-related complications were determined by chart review. CT scan following embolization was not a routine practice in the hospital unit during this period.
Study endpoints
Technical success was defined as the cessation of angiographic extravasation, the absence of pseudoaneurysm filling immediately after embolization, based on the angiographic findings. Clinical success was defined as no rebleeding within 30 days after TAE or recurrence of bleeding that required only medical treatment or repeat TAE. Clinical failure was defined as haemorrhagic related-death or rebleeding that required emergency surgery during the 30-day follow-up.
Rebleeding events were classified as early events if they occurred within 30-days of embolization and as late rebleeding events if they occurred after 30 days of embolization.
Complications were defined as complications during the TAE and post-procedure complications during the follow-up period. Complications have been classified as minor or major according to the Clavien-Dindo classification (Dindo et al., 2004; GmbH A, n.d.). Grade I and II complications do not require treatment or only medical treatment and are classified as minor complications. Grade III, IV and V complications require endoscopic or surgical treatment, are life-threatening or result in death, and are classified as major complications.
Statistical analysis
Qualitative variables are expressed as frequencies and percentages and quantitative variables, as means and standard deviation. Statistical analyses were conducted in STATA software.
Ethical considerations
This study was approved by the Ethic committee of our institute (IRBN112021).