A novel animal model of abdominal aortic aneurysm by mechanical injury.

The present study established a novel and reproducible animal model to study abdominal aortic aneurysms. In total, 22 adult Lewis rats underwent a procedure to produce mechanical injuries at the infrarenal aorta which was opened temporarily. The aortas were injured 6 times and repaired. Those rats were divided into 2 groups and the aortic aneurysm tissue was harvested after 42 (6-week group) or 63 (9-week group) days and evaluated for the progression of aortic aneurysms. In the 6-week group, changes in the aneurysm were observed in 6/10 (60%) rats and the mean maximum diameter of the aorta demonstrated a 119% increase in size from the baseline measurement. In the 9-week group, changes in the aneurysm were observed in 8/11 (88%) rats and the mean maximum diameter of aorta demonstrated a 133% increase in size. Additional findings from the aortic aneurysm tissue were found microscopically, including the destruction of the tunica media and the elastic fiber. The present study demonstrated that this novel animal model for the development of abdominal aortic aneurysms (AAAs) produced by mechanical injury may have high reproducibility and similar gross and microscopic morphology to humans. This model could be helpful to investigate the treatment of AAAs.

Renal function-adjusted contrast medium volume is a major risk factor in the occurrence of acute kidney injury after endovascular aneurysm repair.

ABSTRACT: Acute kidney injury (AKI) is a complication that can occur during endovascular aneurysm repair (EVAR), increasing postoperative mortality and disease-related death. We therefore evaluated the incidence of AKI after elective EVAR, as well as related factors affecting AKI occurrence, investigating the volume of contrast medium (CV)/estimated glomerular filtration rate (eGFR) ratio as a predictive factor.We retrospectively reviewed the data of patients who underwent EVAR for infrarenal abdominal aorta aneurysm at a single center between April 2011 and December 2018. AKI was defined according to the Kidney Disease: Improving Global Outcomes criteria. We evaluated the occurrence of AKI within the first 7 days postoperatively, comparing serum creatinine levels, eGFR, CV, CV/eGFR ratio, fluid input and output, and morbidity between the AKI and no-AKI groups.The data of 147 patients were analyzed, of which 131 (89.1%) were males (mean age: 72.10±7.40 years); the incidence of AKI was 4.1% (6/147 patients). The mean dose of contrast agents used was greater in the AKI group than in the no-AKI group (249.17 ±â€Š83.21 mL vs 179.43 ±â€Š84.32 mL, respectively; P = .05). The baseline eGFR was 42.69 ±â€Š22.08 mL/kg/1.73 m2 in the AKI group and 77.96 ±â€Š18.92 mL/kg/1.73 m2 in the no-AKI group (P = .001). The CV/eGFR ratio was significantly higher in the AKI group (8.21 ±â€Š6.13 vs 2.46 ±â€Š1.44; P = 0.003). Baseline eGFR (odds ratio [OR] = 0.922, P = .001) and the CV/eGFR ratio (OR = 2.049, P = .008) were observed to be factors related to the occurrence of AKI in the logistic regression analysis for patients' characteristics, operation-related factors, and renal outcomes. In the receiver operating characteristic curve analysis, the area under the curve of the CV/eGFR ratio was 0.856, indicating the greatest influence. A CV/eGFR ratio cutoff value of 3.84 was considered the most appropriate, with an 83.3% sensitivity and 83.0% specificity.The CV/eGFR ratio, rather than the absolute amount of contrast agents, was associated with the development of AKI after EVAR. The CV/eGFR ratio could be used as a possible indicator to limit the amount of contrast media required for the procedure.

Efficacy of Regional Anesthesia in Secondary Procedures or Revisions of Arteriovenous Fistula.

BACKGROUND: Several factors affect the outcomes of arteriovenous fistula (AVF) and end-stage renal disease (ESRD). This study aimed to evaluate the efficacy of regional anesthesia in secondary procedures or revisions of AVF. METHODS: Medical records of patients who underwent treatment for AVF secondary procedures or revisions under brachial plexus block (BPB) between March 2016 and June 2019 were retrospectively analyzed. Patient characteristics and clinical outcomes were evaluated. RESULTS: In total, 375 patients (mean age 65.6 ± 12.74; males 210, 56.0%) were enrolled in the study and 770 procedures were performed under BPB for AVF secondary procedures or revisions. The procedures included endovascular treatment (385, 50.0%), surgical treatment (105, 13.6%), and hybrid treatment (280, 36.4%). In 180 procedures (23.4%) for AVF lesions, the operative field included a single segment of the arm, whereas in 590 procedures (76.6%), the operative field included multiple segments. In total, 37 (4.8%) cases of 30-day postoperative complications were observed, of which 33 (4.3%) were surgery-related complications, 2 (0.3%) were BPB-related complications (neurapraxia), and 2 (0.3%) were contrast agent allergic reactions; 34 (4.4%) reinterventions of the total 201 (26.1%) reinterventions were performed within 30 days postoperatively. The mean operation time was 87.5 ± 55.35 min. The pain score for all patients was 0 (no pain), and no patient demanded opioids postoperatively. CONCLUSIONS: Ultrasound-guided BPB is safe and effective for AVF secondary procedures or revisions in ESRD patients.

Endovascular Stenting for a Crush Injury of the Common Femoral Artery Followed by Open Repair of Unveiled External Iliac Vein Injury after a Horse Fall.

Accurate diagnosis and management of a femoral vascular injury is important as it is a life-threatening injury with high morbidity and mortality. This is the case of a 75-year-old man admitted to the emergency room with trauma to the right groin due to a horse fall. Computed tomography showed active bleeding of the femoral artery without pelvic or femoral fracture. We inserted a stent-graft, but hypotension persisted. Exploration of the groin was completed, and the bleeding from the external iliac vein was identified and repaired. In conclusion, vascular injury is rare in groin trauma without associated fracture, however, arterial and venous injury should not be completely ruled out. Endovascular therapy is worth recommending as a quicker and safer management than surgery in patients with active bleeding in the femoral artery. However, the possibility of combined injury of the femoral vein should be suspected in case of ongoing hemodynamic instability.