Risk factors for ischaemic colitis after surgery for abdominal aortic aneurysm: a systematic review and observational meta-analysis

Identification of Perioperative Procedural and Hemodynamic Risk Factors for Developing Colonic Ischemia after Ruptured Infrarenal Abdominal Aortic Aneurysm Surgery: A Single-Centre Retrospective Cohort Study

(1) Background: This retrospective study evaluated perioperative and intensive care unit (ICU) variables to predict colonic ischemia (CI) after infrarenal ruptured abdominal aortic aneurysm (RAAA) surgery. (2) Materials and Methods: We retrospectively analyzed the data of the patients treated for infrarenal RAAA from January 2011 to December 2020 in our hospital. (3) Results: A total of 135 (82% male) patients were admitted to ICU after treatment of infrarenal RAAA. The median age of all patients was 75 years (IQR 68-81 years). Of those, 24 (18%) patients developed CI, including 22 (92%) cases within the first three postoperative days. CI was found more often after open repair compared to endovascular treatment (22% vs. 5%, p = 0.021). Laboratory findings in the first seven PODs revealed statistically significant differences between CI and non-CI patients for serum lactate, minimum pH, serum bicarbonate, and platelet count. Norepinephrine (NE) was used in 92 (68%) patients during ICU stay. The highest daily dose of norepinephrine was administered to CI patients at POD1. Multivariable analysis revealed that NE > 64 µg/kg (RD 0.40, 95% CI: 0.25-0.55, p < 0.001), operating time ≥ 200 min (RD 0.18, 95% CI: 0.05-0.31, p = 0.042), and pH < 7.3 (RD 0.21, 95% CI: 0.07-0.35, p = 0.019), significantly predicted the development of CI. A total of 23 (17%) patients died during the hospital stay, including 8 (33%) patients from the CI group and 15 (7%) from the non-CI group (p = 0.032). (4) Conclusions: CI after RAAA is a sever complication occurring most frequently within the first 3 postoperative days. Our study identified many surrogate markers associated with colonic ischemia after aortic RAAA, including norepinephrine dose > 64 µg/kg, operating time ≥ 200 min, and PH < 7.3. Future studies are needed to support these results.

Arteriocolonic fistula of inferior mesenteric artery aneurysm: A case with lower gastrointestinal and intra-abdominal hemorrhage

Introduction

Arteriocolonic fistula of Inferior Mesenteric Artery Aneurysm (IMAA) refers to a spontaneous formation of pathological communication between the artery and the adjacent gastrointestinal tract. It is a rare, life-threatening condition primarily manifesting as abdominal pain, gastrointestinal bleeding, abdominal pulsating masses. However, its clinical manifestations are usually atypical with a difficult diagnosis and treatment.

Case presentation

We report a rare case of a 50-year-old male with a hemorrhagic shock due to primary arteriocolonic fistula of IMAA. Instead of sigmoidectomy, super selective transcatheter arterial embolization (TAE) was performed after diagnostic angiography. Postoperatively, dynamic contrast-enhanced abdominal computed tomography (CT) demonstrated no recanalization of the aneurysm, absence of abnormal collateral vessels, no active hemorrhage. The patient was discharged uneventfully after 2 weeks without abdominal pain or tension.

Discussion

Colorectal tumor rupture is a major cause of lower gastrointestinal bleeding (LGIB), with IMAA being an uncommon etiology. Because of the high mortality of explorative laparotomy with an unclear bleeding site, diagnostic angiography and therapeutic TAE are viable options for diagnosing hemodynamic instability.

Conclusion

Arteriocolonic fistulas commonly occur secondary to a pseudoaneurysm formed at the anastomosis of the transplanted blood vessel after an artery surgery, which ruptures and penetrates into the intestine. We reported a unique case of primary arteriocolonic fistula of IMAA: aneurysm rupture and bleeding from the abdomen into the hematochezia. After multidisciplinary consultations, our patient obtained the best outcome using the most minimally invasive surgical methods. With an abdominal artery aneurysm presenting with colorectal hemorrhage, arteriocolonic fistula of IMAA should be suspected.

Open Surgery for Abdominal Aortic Aneurysm: 980 Consecutive Patient Outcomes from a High-Volume Centre in the United Kingdom

BACKGROUND

Controversy persists regarding the optimal treatment for large abdominal aortic aneurysm (AAA), highlighted by the publication of the National Institute for Health and Care Excellence (NICE) guideline (NG156) on March 2020. The pendulum of opinion swings once more from endovascular to open surgical treatment. We report our experience over the last 15 years in treating consecutive AAA by open surgery.

METHODS

A retrospective review of a prospectively collected vascular database of all patients undergoing infra-renal open abdominal aortic aneurysm repair (OR) repair from 2004 to 2019 at the largest aneurysm centre in the United Kingdom. OR for elective and emergency (ruptured and symptomatic) outcomes included early morbidity and 30-day mortality, and long-term survival.

RESULTS

1017 patients underwent OR between 2004-2019, on application of our inclusion-criteria 994 patients formed our cohort for analysis (81.2% male) with a mean age 73.6 ± 7.8 years treated by OR for AAA. In that group 672 were elective and 308 were emergency (for ruptured or symptomatic). Overall 30 day mortality was 11.3%, elective 30 day mortality was 2.5%, and emergency 30 day mortality was 29.9%. 30 day re-intervention rate was 9.5%, (elective 7.0%, emergency 15.9%). Survival at 1000 days for elective repair was 72 v 46.7% for emergency and at 2000 days was 43.4% for elective v 25% for emergency.

CONCLUSION

Our data confirm that open surgery for AAA can be performed in large volume centres quite safely. Elective and Emergency surgery does affect early 30 day mortality but does not influence long-term outcome.

MiR-30c-1-3p targets matrix metalloproteinase 9 involved in the rupture of abdominal aortic aneurysms

Abstract

Abdominal aortic aneurysm (AAA) can be fatal if ruptured, but there is no predictive biomarker. Our aim was to evaluate the prognostic potential of microRNAs (miRNAs/miRs) in an AAA mouse model and patients with unruptured AAA (URAAA) and ruptured AAA (RAAA). Among the 64 miRNAs differentially expressed in mice with AAA compared to control, miR-30c-1-3p, miR-432-3p, miR-3154, and miR-379-5p had high homology with human miRNAs. MiR-30c-1-3p plasma levels were significantly lower in patients with RAAA than in those with URAAA or control and tended to negatively correlate with the maximum aortic diameter (r =  −0.3153, P = 0.06109). MiR-30c-1-3p targeted matrix metalloproteinase (MMP)-9 mRNA through the coding region and downregulated its expression in vitro. MMP-9 plasma concentrations were significantly higher in the RAAA group than in the URAAA group (P < 0.001) and were negatively associated with miR-30c-1-3p levels (r =  −0.3671, P = 0.01981) and positively–with the maximal aortic diameter (r = 0.6251, P < 0.0001). The optimal cutoff values for MMP-9 expression and the maximal aortic diameter were 461.08 ng/ml and 55.95 mm, with areas under the curve of 0.816 and 0.844, respectively. Our results indicate that plasma levels of miR-30c-1-3p and MMP-9 may be candidate biomarkers of AAA progression.

Key messages

Downregulation of miR-30c-1-3p expression and upregulation of its potential target MMP-9 are predictors of the devastation of AAA.

Downregulation of miR-30c-1-3p expression and its downstream impact on MMP-9 have a potential on predicting the development and rupture of AAA.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00109-022-02230-2.

A, Thondamala V, Onuchukwu CV, Mohammed L. Emphasis on Early Identification of Risk Factors to Curtail High Mortality Involved With Ischemic Colitis (IC) After Abdominal Aortic Aneurysm (AAA) Repair

Ischemic colitis (IC) is one of the most feared complications after abdominal aortic aneurysm (AAA) repair. Though the complication is seen in only a handful of total repairs, the mortality rates after IC is very high. Due to infrequent presentation, attending doctors may overlook this possibility leading to a delay in diagnosis. Open repair and endovascular aneurysm repair (EVAR) are the two most common methods used for repairing aneurysms and both of these procedures have their implications in the development of IC. While the incidence of IC was greater after open repair, it also harbored more patients with ruptured aneurysms, emergency repairs, and patients in shock. Similarly, a significant proportion of patients having ruptured aneurysms developed IC. Controlling minor variables like acidosis, hypothermia, hypovolemia, and clamp time duration can play a cumulative role in diminishing this hazardous complication. Medical advancements and minimally invasive technologies have improved the quality of care and operation success considerably, but researchers have not identified a statistically significant association in the prevention of postoperative IC. Therefore, early diagnosis and prompt management become crucial in reducing mortality rates. This can be achieved by being aware of impending signs and symptoms especially in patients with risk factors and being proactive in medical management.

Ischaemic colitis: practical challenges and evidence-based recommendations for management

Ischaemic colitis (IC) is a common condition with rising incidence, and in severe cases a high mortality rate. Its presentation, severity and disease behaviour can vary widely, and there exists significant heterogeneity in treatment strategies and resultant outcomes. In this article we explore practical challenges in the management of IC, and where available make evidence-based recommendations for its management based on a comprehensive review of available literature. An optimal approach to initial management requires early recognition of the diagnosis followed by prompt and appropriate investigation. Ideally, this should involve the input of both gastroenterology and surgery. CT with intravenous contrast is the imaging modality of choice. It can support clinical diagnosis, define the severity and distribution of ischaemia, and has prognostic value. In all but fulminant cases, this should be followed (within 48 hours) by lower gastrointestinal endoscopy to reach the distal-most extent of the disease, providing endoscopic (and histological) confirmation. The mainstay of medical management is conservative/supportive treatment, with bowel rest, fluid resuscitation and antibiotics. Specific laboratory, radiological and endoscopic features are recognised to correlate with more severe disease, higher rates of surgical intervention and ultimately worse outcomes. These factors should be carefully considered when deciding on the need for and timing of surgical intervention.

Abdominal aortic aneurysms part two: Surgical management, postoperative complications and surveillance

Large, symptomatic and ruptured abdominal aortic aneurysms are usually treated surgically if patients are deemed fit enough. This may be achieved through endovascular or open surgical repair. The type of treatment that a patient receives is dependant on many factors, such as the rupture status of the aneurysm. Each approach is also associated with different risks and postoperative complications. Multiple guidelines exist to inform the surgical management of abdominal aortic aneurysms. This literature review combines these recommendations and explores the evidence upon which they are based. In addition, it highlights the key perioperative considerations that need to be considered in cases of unruptured and ruptured abdominal aortic aneurysms.

Predictors of mortality following emergency open colectomy for ischemic colitis: a single-center experience

Background

Ischemic colitis (IC) is a severe emergency in gastrointestinal surgery. The aim of the present study was to identify the predictors of postoperative mortality after emergent open colectomy for IC treatment. Additionally, we compared postoperative outcomes of patients undergoing emergent colectomy due to aortic surgery-related IC (AS-IC group) vs. other IC etiologies (Other-IC group).

Methods

We analyzed records of consecutive patients who underwent emergency open colectomy for IC between 2008 and 2019. Logistic regression analysis was performed to identify clinical and operative parameters associated with postoperative mortality. The AS-IC and Other-IC groups were compared for mortality, morbidity, ICU stay, hospital stay, and survival.

Results

During the study period, 94 patients (mean age, 67.4 ± 13.7 years) underwent emergent open colectomy for IC. In the majority of cases, IC involved the entire colon (53.2%) and vasopressor agents were required preoperatively (63.8%) and/or intraoperatively (78.8%). Thirty-four patients underwent surgery due to AS-IC, whereas 60 due to Other-IC causes. In the AS-IC group, 9 patients had undergone endovascular aortic repair and 25 open aortic surgery; 61.8% of patients needed aortic surgery for ruptured abdominal aortic aneurism (AAA). Overall, 66 patients (70.2%) died within 90 days from surgery. The AS-IC and Other-IC groups showed similar operative outcomes and postoperative complication rates. However, the duration of the ICU stay (19 days vs. 11 days; p = 0.003) and of the total hospital stay (22 days vs. 16 days; p = 0.016) was significantly longer for the AS-IC group than for the Other-IC group. The rate of intestinal continuity restoration at 1 year after surgery was higher for the Other-IC group than for the AS-IC group (58.8% vs. 22.2%; p = 0.05). In the multivariate model, preoperative increased lactate levels, a delay between signs/symptoms’ onset and surgery > 12 h, and the occurrence of postoperative acute kidney injury were statistically associated with postoperative mortality. Neither IC etiology (aortic surgery vs. other etiology) nor ruptured AAA was associated with postoperative mortality.

Conclusion

Emergency open colectomy for IC is associated with high postoperative mortality, which appears to be unrelated to the IC etiology. Preoperative lactate levels, > 12-h delay to surgery, and postoperative acute kidney injury are independent predictors of postoperative mortality.

Value of Routine Flexible Sigmoidoscopy and Potential Predictive Factors for Colonic Ischemia after Open Ruptured Abdominal Aortic Aneurysm Repair

Background and Objectives: colonic ischemia (CI) after ruptured abdominal aortic aneurysm (rAAA) repair is associated with increased morbidity and mortality. CI may be detected by using flexible sigmoidoscopy, but routine use of flexible sigmoidoscopy after rAAA is not clearly proven. The objective of this study was to evaluate the efficacy of routine flexible sigmoidoscopy in detecting CI after rAAA repair, and to identify potential hemodynamic, biochemical, and clinical variables that can predict the development of CI in the patients who underwent rAAA surgery. Materials and Methods: we retrospectively included all rAAA cases treated in Viborg hospital from 1 April 2014 until 31 August 2017, recorded the findings on flexible sigmoidoscopy, and the incidence of CI. We collected specific hemodynamic, biochemical, and clinical variables, measured pre- and perioperatively, and the first three postoperative days. The association between CI and possible predictors was analyzed in a logistic regression model. Results: a total of 80 patients underwent open rAAA repair during the study period. Flexible sigmoidoscopy was performed in 58 of 80 patients (73.5%) who survived at least 24 h after open rAAA surgery. Perioperative variables lowest arterial pH (p = 0.02) and types of operations—aortobifemoral bypass vs. straight graft (p = 0.04) showed statistically significant differences between CI groups. The analysis of the postoperative variables showed statistically significant difference in highest lactate on postoperative day 1 (p = 0.01), and lowest hemoglobin on postoperative day 2 (p = 0.04) comparing CI groups. Logistic regression model revealed that postoperative hemoglobin and lactate turned out to be independent risk factors for the development of CI (respectively OR = 0.44 (95% CI = 0.29–0.67) and OR = 1.91 (95% CI = 1.2–3.05)). Conclusions: flexible sigmoidoscopy can identify patients being at higher risk of mortality after open rAAA repair. The postoperative lactate and hemoglobin were found to be independent risk factors for the development of CI after open rAAA repair. Further larger studies are warranted to demonstrate these findings.

Outcomes Following Inferior Mesenteric Artery Reimplantation During Elective Aortic Aneurysm Surgery

BACKGROUND

The role of inferior mesenteric artery (IMA) reimplantation during open aortic reconstruction is debated. We assessed outcomes after inferior mesenteric artery reimplantation (IMAR) for aortic aneurysmal disease to help shed light on this question.

METHODS

A single-center retrospective review of all IMARs performed during open aortic surgery over a 10-year period between 2000 and 2009 was carried out. The primary outcome was patency, while secondary outcomes included colonic ischemia and overall survival. Analysis was performed using Cox models and Kaplan-Meier estimates.

RESULTS

Of 840 patients who underwent elective abdominal aortic aneurysm (AAA) reconstructions during this period, 70 underwent IMAR. Indications for IMAR included intraoperative colonic ischemia (n = 24), poor back bleeding (n = 52), large IMA (n = 5), internal iliac disease (n = 5), and prior colon surgery (n = 1). Follow-up imaging studies were available in 35 of 70 patients (computed tomography in 30 [86%] and duplex in 5 [14%]). Patency was confirmed in 32 of 35 patients (91%) over a median follow-up of 98 months. Both losses in patency were at 4 months and did not require an operation. One patient underwent left colon resection on postoperative day 9 because of ischemia. (Patency could not be confirmed.) No statistically significant predictor of patency was noted. Incidence of colonic ischemia was 1.4% in patients undergoing IMAR. The overall mortality was 51% in patients undergoing IMAR over the median follow-up period. The overall 10-year survival was 30% in patients undergoing IMAR for aortic aneurysmal disease. The nature of aneurysm (juxtarenal or higher juxta renal abdominal aortic aneurysm [JRAAA]) was associated with mortality, with a hazard ratio of 1.8 (P = 0.08) approaching significance. Ten-year survival was worse if IMAR was performed for intraoperative colonic ischemia (26% vs 34%) or in JRAAA (19.0% vs 38%; P = 0.03). Age per year at the time of repair was the only statistically significant predictor of survival (P < 0.001).

CONCLUSION

IMAR for AAA remains necessary for select patients. Reimplantation is associated with excellent long-term patency and low risk of colonic ischemia.

Ischemic colitis following infrarenal abdominal aortic aneurysm treatment: Results from a tertiary medical center

OBJECTIVE

The aim of this study was to investigate the effects of ruptured aneurysm on morbidity and mortality in patients with ischemic colitis (IC) and resection following infrarenal abdominal aortic aneurysms (AAA) surgery.

METHODS

Between January 2012 and December 2016, patients who underwent resection for ischemic colitis in our clinic were retrospectively reviewed. Data on the ruptured condition of the aneurysm, the emergency or elective form of aneurysm surgery, treatment method for the aneurysm (EVAR-open) were obtained. The patients were compared and divided into two groups as those with ruptured aneurysm and those without.

RESULTS

A total of 275 infrarenal AAA cases were treated by the cardiovascular surgery clinic between January 2012 and December 2016. Fourteen patients (5%) developed ischemic colitis requiring resection. Four (1.8%) patients with EVAR and 10 (17.5%) patients with open surgery were operated because of IC. No statistically significant difference was observed between the two groups in terms of demographic data and surgical procedures. The intergroup comparison did not reveal any statistically significant difference among gastrointestinal (GIS) symptoms, the time period until surgery, the involved colon segment, and the surgical procedures performed. The mortality rate in ruptured AAA group was 83.3%, while it was 62.5% in the non-ruptured AAA group. In spite of the fact that the mortality rate was high in the ruptured group, it was not statistically significant (p=0.393).

CONCLUSION

IC is a complication of AAA surgery with a high mortality rate. Rupture in abdominal aortic aneurysm increasing mortality in IC patients. This complication with a high mortality rate following open AAA surgery should be noted by surgeons and we believe that the liberal utilization of laparotomy and early intervention in suspected cases will decrease mortality rates.

Inferior mesenteric artery replantation does not decrease the risk of ischemic colitis after open infrarenal abdominal aortic aneurysm repair

BACKGROUND

Ischemic colitis after an open abdominal aortic aneurysm (AAA) repair remains a serious complication with a nationally reported rate of 1% to 6% in elective cases and up to 60% after an aneurysmal rupture. To prevent this serious complication, inferior mesenteric artery (IMA) replantation is performed at the discretion of the surgeon based on his or her intraoperative findings, despite the lack of clear evidence to support this practice. The purpose of this study was to determine whether replantation of the IMA reduces the risk of ischemic colitis and improves the overall outcome of AAA repair.

METHODS

Patients who underwent open infrarenal AAA repair were identified in the multicenter American College of Surgeons National Surgical Quality Improvement Program Targeted AAA Database from 2012 to 2015. Emergency cases, patients with chronically occluded IMAs, ruptured aneurysms with evidence of hypotension, and patients requiring visceral revascularization were excluded. The remaining elective cases were divided into two groups: those with IMA replantation (IMA-R) and those with IMA ligation. We measured the 30-day outcomes including mortality, morbidity, and perioperative outcomes. A multivariable logistic regression model was used for data analysis, adjusting for clinically relevant covariates.

RESULTS

We identified 2397 patients who underwent AAA repair between 2012 and 2015, of which 135 patients (5.6%) had ischemic colitis. After applying the appropriate exclusion criteria, there were 672 patients who were included in our study. This cohort was divided into two groups: 35 patients with IMA-R and 637 patients with IMA ligation. There were no major differences in preoperative comorbidities between the two groups. IMA-R was associated with increased mean operative time (319.7 ± 117.8 minutes vs 242.4 ± 109.3 minutes; P < .001). Examination of 30-day outcomes revealed patients with IMA-R had a higher rate of return to the operating room (20.0% vs 7.2%; P = .006), a higher rate of wound complications (17.1% vs 3.0%; P = .001), and a higher incidence of ischemic colitis (8.6% vs 2.4%; P = .027). There were no significant differences in mortality, pulmonary complications, or renal complications between the two groups. In multivariable analysis, IMA-R was a significant predictor of ischemic colitis and wound complications.

CONCLUSIONS

These data suggest that IMA-R is not associated with protection from ischemic colitis after open AAA repair. The role of IMA-R remains to be identified.

Incidence, Predictors, and Outcomes of Colonic Ischaemia in Abdominal Aortic Aneurysm Repair

OBJECTIVE/BACKGROUND

Colonic ischaemia (CI) is a severe complication following abdominal aortic aneurysm (AAA) repair, leading to high morbidity and mortality. The aim of the study was to determine the incidence, predictors, and outcomes of CI following AAA repair.

METHODS

National claims from Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate CI after intact (iAAA) and ruptured (rAAA) AAA repairs. Patients undergoing endovascular (EVAR) or open surgical (OSR) repairs between January 2008 and December 2017 were included in the study.

RESULTS

There were 9145 patients (8248 iAAA and 897 rAAA) undergoing EVAR or OSR procedures and the median follow up was 2.28 years. Most patients were male (79.2% iAAA, 79.3% rAAA); the median age was 73.0 years (iAAA group) and 76.0 years (rAAA group). Overall, CI occurred 97 (1.2%) times after iAAA and 95 (10.6%) after rAAA. In univariable analyses CI occurred less often after EVAR than after OSR (0.6% vs. 3.7%; p < .001). Acute post-operative renal and respiratory insufficiencies were also related to the occurrence of CI (p < .001). CI was associated with greater in hospital mortality (42.2% vs. 2.7% for iAAA, 64.2% vs. 36.3% for rAAA; p < .001) and lower long-term survival for iAAA (Kaplan-Meier analysis). In multivariable analyses, rAAA (odds ratio [OR] 5.59), and higher van Walraven comorbidity score (OR 1.09) were independently associated with greater risk of CI occurrence. EVAR use (OR 0.30) was protective. EVAR use remained protective in stratified analyses within iAAA (OR 0.32) and rAAA (OR 0.26).

CONCLUSION

Post-operative CI after AAA repair is not common but is associated with worse in hospital outcomes and lower long-term survival. EVAR was protective after both rAAA and iAAA repairs. When discussing the treatment of AAA with patients the protective effect of EVAR should be considered. Future studies should validate predictive scores and advance preventive strategies.

Elective Repair of Abdominal Aortic Aneurysm and the Risk of Colonic Ischaemia: Systematic Review and Meta-Analysis

INTRODUCTION

Colon ischaemia (CI) is a significant complication of open (OR) and endovascular (EVAR) repair of abdominal aortic aneurysm (AAA). With a rapid increase in EVAR uptake, contemporary data demonstrating the differing rates and outcomes of CI between EVAR and OR, particularly in the elective setting, are lacking. The aim was to characterise the risk and consequences of CI in elective AAA repair comparing EVAR with OR.

METHODS

A systematic review and meta-analysis of the literature was performed using the Cochrane collaboration protocol and reported according to the PRISMA guidelines. PubMed, MedLine, and EMBASE were searched for studies reporting CI rates after elective AAA repair. Ruptured AAAs were excluded from analysis.

RESULTS

Thirteen studies reporting specific outcomes of CI after elective AAA repair, containing 162,750 evaluable patients (78,151 EVAR and 84,599 OR) were included. All studies found a higher risk of CI with OR than with EVAR. Three studies performed confounder adjustment with CI rates of 0.5-1% versus 2.1-3.6% (EVAR vs. OR) and combined odds ratio of 2.7 (2.0-3.5) for the development of CI with OR versus EVAR. The majority of cases of CI occurred within 30 days and were associated with variable mortality (0-73%) and re-intervention rates (27-54%). GRADE assessment of evidence strength was very low for all outcomes. There was a high degree of heterogeneity between studies both methodologically and in terms of CI rates, re-intervention, mortality, and time to development of CI.

CONCLUSIONS

EVAR is associated with a reduced incidence of CI compared with OR.

Accuracy of Routine Endoscopy Diagnosing Colonic Ischaemia After Abdominal Aortic Aneurysm Repair: A Meta-analysis

BACKGROUND

Colonic ischaemia (CI) is a devastating complication after abdominal aortic aneurysm (AAA) surgery. The aim of this review was to evaluate the diagnostic test accuracy of routine endoscopy in diagnosing CI after treatment for elective and acute AAA.

PATIENTS AND METHODS

The Pubmed and Embase database searches resulted in 1188 articles. Prospective studies describing routine post-operative colonoscopy or sigmoidoscopy after elective or emergency AAA repair were included. The study quality was assessed with the QUADAS-2 tool. Sensitivity and specificity forest plots were drawn. Diagnostic odds ratios were calculated by a random effect model.

RESULTS

Twelve articles were included consisting of 718 AAA patients of whom 44% were treated electively, 56% ruptured and, 6% by endovascular repair. Of all patients, 20.8% were identified with CI (all grades), and 6.5% of patients had Grade 3 CI. The pooled diagnostic odds ratio for all grades of CI on endoscopy was 26.60 (95% CI 8.86-79.88). The sensitivity and specificity of endoscopy for detection of Grade 3 CI after AAA repair was 0.52 (95% CI, 0.31-0.73) and 0.97 (95% CI 0.95-0.99) respectively. The positive post-test probability is up to 60% in all kinds of AAA patients and 68% in ruptured AAA patients.

CONCLUSION

Routine endoscopy is highly accurate for ruling out CI after AAA repair. Clinicians should be aware that endoscopy is less accurate in diagnosing the presence of the clinically relevant transmural CI. Endoscopy is a safe diagnostic test to use routinely as none of the studies reported adverse events.

Low mortality rates after endovascular aortic repair expand use to high-risk patients

OBJECTIVE

The 2010 endovascular aneurysm repair (EVAR) trial 2 (EVAR 2) reported that patients with comorbidity profiles rendering them unfit for open aneurysm repair who underwent EVAR did not experience a survival advantage compared with those who did not undergo intervention. These patients experienced a 30-day mortality of 7.3%, whereas reports from similar cohorts reported far lower mortality rates. The primary objective of our study was to compare the incidence of 30-day mortality in low- and high-risk patients undergoing EVAR in a contemporary data set, using patient risk stratification criteria from EVAR 2. Secondarily, we sought to identify risk factors associated with a disproportionate contribution to 30-day mortality risk.

METHODS

Data were obtained from the 2005 to 2013 American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) Participant Use Data Files (N = 24,813). Patients were included in the high-risk cohort with the presence of renal, respiratory, or cardiac preoperative criteria alone or in combination. Renal impairment criteria were defined as dialysis and creatinine concentration >2.26 mg/dL. Respiratory impairment criteria included history of chronic obstructive pulmonary disease and preoperative ventilator support. Cardiac impairment criteria included history of myocardial infarction, congestive heart failure, angina, and prior coronary intervention. Patient and procedural characteristics and 30-day postoperative outcomes were compared using Pearson χ2 tests for categorical variables and Wilcoxon rank sum tests for continuous variables.

RESULTS

Among 24,813 patients undergoing EVAR, 12,043 (48%) patients were characterized as high risk (at least one impairment criterion); 12,770 (52%) patients were stratified as low risk. The 30-day mortality rate was 1.9% in the high-risk cohort compared with the 7.3% reported by EVAR 2, and it was higher in the high-risk cohort compared with the low-risk cohort (1.9% vs 0.9%; P < .001). Whereas the presence of each comorbidity increased the odds of 30-day mortality (respiratory odds ratio [OR], 1.62; 95% confidence interval [CI], 1.16-2.26; P = .005; cardiac OR, 1.55; 95% CI, 1.14-2.10; P = .005), the presence of renal criteria disproportionately increased the odds of mortality threefold (OR, 3.42; 95% CI, 2.31-5.09; P < .001).

CONCLUSIONS

Contemporary 30-day mortality after EVAR in high-risk patients is substantially lower than that reported in the EVAR 2 trial. Whereas low- and high-risk stratification by current comorbidity criteria is appropriate, attention needs to be paid to disproportionate risk contribution from renal disease to mortality compared with cardiac and pulmonary comorbidities. Given the lower mortality risk than previously described, patients stratified as high risk should be thoughtfully considered for definitive EVAR.

A case of a rectal stricture related to ischemic proctitis following rupture of an aortic aneurysm

Background and study aims  Ischemic proctitis is a rare disease and comprises 2 % to 5 % of cases of ischemic colitis, because the rectum has abundant blood supply and rich collaterals. Herein, we report a case of a 73-year-old male patient with a pronounced rectal stricture caused by ischemic proctitis resulting from an abdominal aortic rupture and treated by endoscopic balloon dilation therapy. To date, only 3 cases of rectal stricture related to ischemic proctitis including our case have been reported, and this is the first case of rectal stricture related to ischemic proctitis, which was successfully treated by endoscopic balloon dilation.

Delayed Sigmoid Ischemic Rupture Following Open Repair Abdominal Aortic Aneurysm

Colon ischemia following aortic reconstruction is a severe complication with an incidence of 1% to 2% of the operated patients; this infrequent complication will be lethal for nearly half of these patients. Commonly, colon ischemia may be an intraoperative observation or an early postoperative finding. However, in the case presented here, sigmoid rupture and small and large intestine communication was revealed 3 months following repair of the abdominal aorta. A 71-year-old man, following open repair of an abdominal aortic aneurysm, went home on the fifth postoperative day. Four months later, he was admitted to the emergency department of our hospital, because of fever, diarrhea, and abdominal pain for about 5 days. After conservative treatment and improvement in symptoms, the patient was released only to return to hospital with the same symptoms after a month. On this second admission, the symptoms were initially mild and the patient seemed to improve, but suddenly he deteriorated and an exploratory laparotomy was conducted, which revealed a left colon ischemia and a communication between the sigmoid and the small intestine. A left hemicolectomy was performed, along with a temporary colostomy (Hartmann diversion). The patient, 2 years after the initial aortic repair and 10 months following the complete restoration of the large intestine continuity, is well with no further manifestations.