Induced Moderate Hypothermia in Aortic Rupture With Retroperitoneal Bleeding: A Randomized Porcine Study.

OBJECTIVE: Induced hypothermia improves outcome in aortic arch surgery, neonatal neurointensive care, and transplant surgery for example. In contrast, spontaneous hypothermia has been associated with worse outcomes in patients suffering from hemorrhagic shock, mostly explained by its adverse effects on the coagulation system. We investigated if induced hypothermia would impair short-term survival in experimental aortic rupture with retroperitoneal bleeding. METHODS: Anesthetized pigs were randomized into 2 groups: hypothermia by peritoneal lavage of ice-cold Ringer's acetate and external cooling (n = 10) and normothermia (n = 10). Aortic rupture with retroperitoneal bleeding was induced by endovascular means creating a 6 mm hole in the retroperitoneal portion of abdominal aorta. Survival (primary outcome), hemodynamics, and arterial blood gases including lactate were collected and analyzed up to 180 min after aortic rupture. RESULTS: The body temperature (mean ± standard deviation) in the hypothermic group was 31.5 ± 1.0 °C and 38.7 ± 0.4 °C in the normothermic group at the time for aortic rupture. Survival up to 180 min after the retroperitoneal bleeding was significantly higher in the hypothermic compared with the normothermic group (P = 0.023). CONCLUSIONS: Induced hypothermia did not impair survival in this experimental retroperitoneal aortic bleeding model in anesthetized pigs. This finding may indicate a minor role for the coagulation system in this type of bleeding.

Intestinal Fatty Acid-Binding Protein as a Potential Biomarker for Gastrointestinal Complications after Complex Endovascular Aortic Surgery.

BACKGROUND: This study aimed to investigate the association between intestinal fatty acid-binding protein (I-FABP), acute gastrointestinal injury (AGI) grade, and gastrointestinal (GI) complications after fenestrated or branched endovascular aortic aneurysm repair. METHODS: A total of 17 patients undergoing endovascular aortic repair for thoracoabdominal, juxtarenal, suprarenal, or pararenal aneurysm between May 2017 and September 2018 were enrolled. Blood samples were collected preoperatively and during postoperative intensive care. The blood samples were analyzed for I-FABP with enzyme-linked immunosorbent assay. Gastrointestinal function was assessed according to the AGI grade every day during postoperative intensive care. RESULTS: Higher concentrations of I-FABP at 24 hr and 48 hr correlated to higher AGI grade on postoperative days 1, 2, and 3 (P = 0.032 and P = 0.048, P = 0.040 and P = 0.018, and P = 0.012 and P = 0.016, respectively). Patients who developed a GI complication within 90 days postoperatively had a higher overall AGI grade than those who did not develop a GI complication (P < 0.001), as well as higher concentrations of I-FABP at 48 hrs (P = 0.019). Patients developing GI dysfunction (AGI grade ≥2) had a higher frequency of complications (P = 0.009) and longer length of stay in the intensive care unit (P = 0.008). CONCLUSIONS: In patients undergoing endovascular aortic repair for complex aneurysm increased postoperative plasma I-FABP concentrations and postoperative GI dysfunction, evaluated using the AGI grade, were associated with GI complications, indicating that these measures may be useful in the postoperative management of these patients.

Multicenter parallel randomized trial evaluating incisional negative pressure wound therapy for the prevention of surgical site infection after lower extremity bypass.

OBJECTIVE: Incisional negative pressure wound therapy (iNPWT) applied over all incisions after lower extremity bypass in the prevention of surgical site infections (SSIs) is unclear. The primary and secondary aims of this study were to investigate if prophylactic iNPWT after the elective lower extremity bypass prevents SSI and other surgical wound complications. METHODS: This was a multicenter, parallel, randomized controlled trial. Patients undergoing elective lower extremity bypass in 3 hospitals were randomized to either iNPWT or standard dressings. SSIs or other wound complications were assessed within the first 90 days by wound care professionals blinded to the randomized result. The validated Additional treatment, Serous discharge, Erythema, Purulent exudate, Separation of deep tissues, Isolation of bacteria, and Stay (ASEPSIS) score was used to objectively assess the wounds. ASEPSIS score ≥21 is defined as an SSI. Unilateral and bilateral groups were analyzed with the Fisher exact test and the McNemar test, respectively. RESULTS: In the unilateral group (n = 100), the incidence of SSI in the iNPWT group was 34.9% (15/43), compared with 40.3% (23/57) in the control group, according to the ASEPSIS score (P = .678). In the bilateral group (n = 7), the SSI rate was 14.3% (1/7) in the iNPWT group compared with 14.3% (1/7) in the control group (P = 1.00). In the unilateral group, there was a higher wound dehiscence rate in the control group (43.9%) compared with the iNPWT group (23.3%) (P = .0366). No serious iNPWT-related adverse events were recorded. CONCLUSIONS: There was no reduction of SSI rates in leg incisions with iNPWT compared with standard dressings in patients undergoing elective lower extremity bypass, whereas iNPWT reduced the incidence of wound dehiscence.

A 12-year experience of endovascular repair for ruptured abdominal aortic aneurysms in all patients.

OBJECTIVE: Endovascular aneurysm repair (EVAR) has been increasingly performed for ruptured abdominal aortic aneurysms (rAAAs). However, multiple randomized trials have failed to demonstrate a survival benefit compared with open aortic surgery. During a 12-year period, 100% of patients without a history of aneurysm surgery had undergone EVAR for a rAAA at Örebro University Hospital, with no emergent open aortic surgery performed. In the present study, we evaluated the mortality and technical success during this "EVAR-only" period. METHODS: A single-center, retrospective observational study was conducted. We identified all patients who had presented to Örebro University Hospital with a rAAA between October 2009 and September 2021. Patients with isolated iliac artery, thoracic, and thoracoabdominal aortic ruptures were not included. Patients who had received previous aortic interventions (open or endovascular) and patients who had received palliative treatment instead of surgical intervention were also excluded. The patient characteristics, perioperative and postoperative data, and mortality rate were investigated. RESULTS: EVAR had been performed in 100 patients. Preoperative hemodynamic instability had been present in 54 patients (54%), and 18 (18%) had undergone aortic balloon occlusion. The aneurysm location was infrarenal in 89 patients (89%). Bifurcated stent grafts had been used in 97 patients (97%), and adjunct endovascular techniques had been used for 27 patients (27%). Of 98 patients, EVAR had been performed with the patient under local anesthesia for 62 patients (63%). Peri- and postoperative complications at 30 days had occurred in 20 of 100 patients (20%) and 22 of 79 patients (28%), respectively. The overall mortality at 30 days was 27% (27 of 100 patients), and the mortality for those with an isolated infrarenal rAAA was 24% (21 of 89 patients). The overall mortality at 1 year was 39% (39 of 100 patients) and for those with an isolated infrarenal rAAA was 37% (33 of 89 patients). The presence of preoperative hemodynamic instability and the use of ABO were statistically significantly and independently associated with increased 30-day mortality on multivariate logistic regression analysis. CONCLUSIONS: All 100 patients who had undergone surgery for a rAAA had been treated using EVAR and endovascular adjuncts, with a relatively low mortality rate, thus continuing the "EVAR-only" approach. A low proportion of rAAA patients were considered surgically unsuitable. These findings support the applicability of EVAR for the treatment of all rAAAs at suitable centers.

Negative Pressure Wound Therapy for the Prevention of Surgical Site Infections Using Fascia Closure After EVAR-A Randomized Trial.

BACKGROUND: Surgical site infections (SSI) in the groin after vascular surgery are common. The aim of the study was to evaluate the effect of negative pressure wound therapy (NPWT) on SSI incidence when applied on closed inguinal incisions after endovascular aneurysm repair (EVAR). METHODS: A multicenter randomized controlled trial (RCT). Between November 2013 and December 2020, 377 incisions (336 bilateral and 41 unilateral) from elective EVAR procedures with the primary intent of fascia closure were randomized and included, receiving either NPWT or a standard dressing. In bilateral incisions, each incision randomly received the opposite dressing of the other side, thereby becoming each other's control. The primary endpoint was SSI incidence at 90 days postoperatively, analyzed on an intention-to-treat basis. Uni and bilaterally operated incisions were analyzed separately, and their respective p-values combined using Fisher's method for combining P-values. Study protocol (NCT01913132). RESULTS: The SSI incidence at 90 days postoperatively in bilateral incisions was 1.8% (n = 3/168) in the NPWT and 4.8% (n = 8/168) in the standard dressing group, and in unilateral incisions 13.3% (n = 2/15) and 11.5% (n = 3/26), respectively (combined p = 0.49). In all SSIs, bacteria were isolated from incisional wound cultures. No additional SSIs were diagnosed between 90 days and 1 year follow-up. CONCLUSIONS: No evidence of difference in SSI incidence was seen in these low-risk inguinal incisions when comparing NPWT with standard dressings after EVAR with the primary intent of fascia closure. CLINICAL TRIALS: NCT01913132.

Novel Experimental Technique to Create Size-Controlled Retroperitoneal Bleeding in the Infrarenal Aorta of Anesthetized Pigs.

OBJECTIVE: Rupture of abdominal aortic aneurysm (rAAA) with a contained retroperitoneal hematoma is potentially fatal. Physiological studies are difficult to perform in patients suffering from life-threatening conditions such as rAAA. A translational model of the condition is therefore needed. The aim was to develop and validate an endovascular animal model for retroperitoneal bleeding of the abdominal aorta with contained hematoma. METHODS: In anesthetized pigs, a puncture hole was made in the posterolateral portion of the infrarenal aorta by an Outback re-entry catheter device. The hole was gradually enlarged using angioplasty balloons to a specific diameter of either 4 mm (n = 6), 6 mm (n = 7), or 8 mm (n = 6). Onset of bleeding was verified by angiography and macroscopically examined on completion of the experiments. Survival up to 180 min was the primary outcome. Hemodynamic and metabolic markers in arterial blood were secondary outcomes. RESULTS: Aortic injury with a contained retroperitoneal hematoma was achieved in all animals. Survival rate at 180 min after onset of bleeding was higher in the 4 mm group compared to the 6 mm (P = 0.021) and 8 mm groups (P = 0.002), but not when comparing the 6 mm and 8 mm groups. Systemic hypotension, arterial acidosis, and lactatemia were provoked in the 6 mm and 8 mm groups but not in the 4 mm group. CONCLUSIONS: A porcine model for a controlled contained left posterolateral retroperitoneal bleeding was created using endovascular methods and validated. This model makes it possible to study the pathophysiology of a retroperitoneal hematoma.

Aortic balloon occlusion (REBOA) in pelvic ring injuries: preliminary results of the ABO Trauma Registry.

EndoVascular and Hybrid Trauma Management (EVTM) has been recently introduced in the treatment of severe pelvic ring injuries. This multimodal method of hemorrhage management counts on several strategies such as the REBOA (resuscitative endovascular balloon occlusion of the aorta). Few data exist on the use of REBOA in patients with a severely injured pelvic ring. The ABO (aortic balloon occlusion) Trauma Registry is designed to capture data for all trauma patients in hemorrhagic shock where management includes REBOA placement. Among all patients included in the ABO registry, 72 patients presented with severe pelvic injuries and were the population under exam. 66.7% were male. Mean and median ISS were respectively 43 and 41 (SD ± 13). Isolated pelvic injuries were observed in 12 patients (16.7%). Blunt trauma occurred in 68 patients (94.4%), penetrating in 2 (2.8%) and combined in 2 (2.8%). Type of injury: fall from height in 15 patients (23.1%), traffic accident in 49 patients (75.4%), and unspecified impact in 1 patient (1.5%). Femoral access was gained pre-hospital in 1 patient, in emergency room in 43, in operating room in 12 and in angio-suite in 16. REBOA was positioned in zone 1 in 59 patients (81,9%), in zone 2 in 1 (1,4%) and in zone 3 in 12 (16,7%). Aortic occlusion was partial/periodical in 35 patients (48,6%) and total occlusion in 37 patients (51,4%). REBOA associated morbidity rate: 11.1%. Overall mortality rate was 54.2% and early mortality rate (≤ 24 h) was 44.4%. In the univariate analysis, factors related to early mortality (≤ 24 h) are lower pH values (p = 0.03), higher base deficit (p = 0.021), longer INR (p = 0.012), minor increase in systolic blood pressure after the REBOA inflation (p = 0.03) and total aortic occlusion (p = 0.008). None of these values resulted significant in the multivariate analysis. In severe hemodynamically unstable pelvic trauma management, REBOA is a viable option when utilized in experienced centers as a bridge to other treatments; its use might be, however, accompanied with severe-to-lethal complications.

Outcome After Endovascular Repair of Ruptured Descending Thoracic Aortic Aneurysm: A National Multicentre Study.

OBJECTIVE: The purpose of this multicentre study was to analyse the outcome of thoracic endovascular aortic repair (TEVAR) in patients with ruptured descending thoracic aortic aneurysm (rDTAA). METHODS: This is a nationwide retrospective study including all patients who underwent TEVAR for rDTAA at six major vascular university centres in Sweden between January 2000 and December 2015. Outcome measures were analysed using Kaplan-Meier estimator and multivariable Cox regression. RESULTS: There were 140 patients (age [mean ± SD] 74.1 ± 8.8 years; 56% men; aneurysm size 64.8 ± 19 mm), with rDTAA. In 53 patients (37.9%), the left subclavian artery was covered, and in 25 patients (17.9%) arch vessel revascularisation was performed. In total, 61/136 patients (45%) had a major complication within 30 days post TEVAR. Stroke (n = 20; 14.7%) was the most common complication, followed by paraplegia (n = 13; 9.6%) and major bleeding (n = 13; 9.6%). TEVAR related complications during follow up included endoleaks 22.1% (30/136; 14 type 1a, six type 1b, 10 not defined). In total, re-interventions (n = 31) were required in 27/137 (19.7%) patients. The median follow up time was 17.0 months (range 0-132 months). The Kaplan-Meier estimated survival was 80.0% at one month, 71.7% at three months, 65.3% at one year, 45.9% at three years, and 31.9% at five years. Age (HR 1.03; 95% CI 1.00-1.07; p = .046), history of stroke (HR 2.35; 95% CI 1.19-4.63; p = .014), previous aortic surgery (HR 2.11; 95% CI 1.15-3.87; p = .016) as well as post-operative major bleeding (HR 4.40; 95% CI 2.20-8.81; p = .001), stroke (HR 2.63; 95% CI 1.37-5.03; p = .004), and renal failure (HR 8.25; 95% CI 2.69-25.35; p = .001) were all associated with mortality. CONCLUSIONS: This nationwide multicentre study of patients with rDTAA undergoing TEVAR showed acceptable short- but poor long-term survival. Adequate proximal and distal aortic sealing zones are important for technical success. High risk patients and post-operative complications need to be further addressed in an effort to improve outcome.

Nationwide Study on Treatment of Mycotic Thoracic Aortic Aneurysms.

OBJECTIVE: Mycotic aortic aneurysms are rare, life threatening, and complex. This nationwide study aimed to assess outcome after repair of mycotic thoracic aortic aneurysms (MTAAs). METHODS: Patients treated in Sweden for MTAAs between 2000 and 2016 were identified in the Swedish vascular registry (2010-16) and local patient registries (2000-09). Primary outcome was survival, and secondary outcomes included surgical strategy, rate of infection related complications (IRC), and re-operations. RESULTS: Fifty-two patients (median age 71 ± 8.1 years; 28 [54%] men, 13 [25%] ruptured) were identified (3.6% of all thoracic aortic aneurysm repairs in Sweden). Aneurysm location was aortic arch (n = 6; 11%), descending aorta (n = 42; 81%), and multiple locations (n = 4; 8%). Twenty-nine (56%) patients had positive cultures; the most prevalent agent was Staphylococcus aureus (n = 16; 31%). Operative techniques included thoracic endovascular aortic repair (TEVAR; n = 35 [67%]), fenestrated/branched TEVAR (n = 8; 15%), hybrid repair (n = 7; 14%), and open patch repair (n = 2; 4%). Survival was 92% (95% confidence interval [CI] 88-96) at 30 days, 88% (95% CI 84-93) at three months, 78% (73-84) at one year, and 71% (64-77) at five years. The mean follow up among survivors (> 90 days) was 45 months (range 4-216 months). Antibiotics were administered for a median of 15 weeks (range 0-220 weeks). IRCs occurred in nine patients (17%): sepsis (n = 3), graft infection (n = 3), recurrent mycotic aneurysm (n = 1), aorto-oesophageal/bronchial fistula (n = 2). Six (67%) IRCs were fatal; 80% occurred within the first year. Re-operations were performed in nine patients (17%). CONCLUSIONS: TEVAR was often used as treatment for MTAAs, with acceptable short- and long-term survival when compared with open cohorts in the literature. IRCs are of concern and warrant follow up and long-term antibiotic treatment.

Use of Resuscitative Endovascular Balloon Occlusion of the Aorta in a Multidisciplinary Approach.

The usage of resuscitative endovascular balloon occlusion of the aorta, also known as aortic balloon occlusion, is an emerging method for bleeding control as a bridge to definitive treatment in trauma management. We describe a trauma case where resuscitative endovascular balloon occlusion of the aorta was used as part of the EndoVascular hybrid Trauma and bleeding Management concept to facilitate transient hemorrhage control and thereby to permit damage control surgery. The case is an illustration of the adoption of a multidisciplinary approach.

EndoVascular and Hybrid Trauma Management (EVTM) for Blunt Innominate Artery Injury with Ongoing Extravasation.

Innominate artery (IA) traumatic injuries are rare but life-threatening, with high mortality and morbidity. Open surgical repair is the treatment of choice but is technically demanding. We describe a case of blunt trauma to the IA with ongoing bleeding, treated successfully by combined (hybrid) endovascular and open surgery. The case demonstrates the immediate usage of modern endovascular and surgical tools as part of endovascular and hybrid trauma management.

Endovascular treatment of mycotic aortic aneurysms: a European multicenter study.

BACKGROUND: Mycotic aortic aneurysm (MAA) is a rare and life-threatening disease. The aim of this European multicenter collaboration was to study the durability of endovascular aortic repair (EVAR) of MAA, by assessing late infection-related complications and long-term survival. METHODS AND RESULTS: All EVAR treated MAAs, between 1999 and 2013 at 16 European centers, were retrospectively reviewed. One hundred twenty-three patients with 130 MAAs were identified. Mean age was 69 years (range 39-86), 87 (71%) were men, 58 (47%) had immunodeficiency, and 47 (38%) presented with rupture. Anatomic locations were ascending/arch (n=4), descending (n=34), paravisceral (n=15), infrarenal aorta (n=63), and multiple (n=7). Treatments were thoracic EVAR (n=43), fenestrated/branched EVAR (n=9), and infrarenal EVAR (n=71). Antibiotic was administered for mean 30 weeks. Mean follow-up was 35 months (range 1 week to 149 months). Six patients (5%) were converted to open repair during follow-up. Survival was 91% (95% confidence interval, 86% to 96%), 75% (67% to 83%), 55% (44% to 66%), and 41% (28% to 54%) after 1, 12, 60, and 120 months, respectively. Infection-related death occurred in 23 patients (19%), 9 after discontinuation of antibiotic treatment. A Cox regression analysis demonstrated non-Salmonella-positive culture as predictors for late infection-related death. CONCLUSIONS: Endovascular treatment of MAA is feasible and for most patients a durable treatment option. Late infections do occur, are often lethal, and warrant long-term antibiotic treatment and follow-up. Patients with non-Salmonella-positive blood cultures were more likely to die from late infection.