The Rationale for Continuing Open Repair of Ruptured Abdominal Aortic Aneurysm

Modern management of ruptured abdominal aortic aneurysm

Ruptured abdominal aortic aneurysms (rAAA) remain one of the most clinically challenging and technically complex emergencies in contemporary vascular surgery practice. Over the past 30 years, a variety of changes surrounding the treatment of rAAA have evolved including improvements in diagnosis, development of coordinated referral networks to transfer patients more efficiently to higher volume centers, deliberate de-escalation of pre-hospital resuscitation, modification of patient and procedure selection, implementation of clinical pathways, as well as enhanced awareness of certain high-impact postoperative complications. Despite these advances, current postoperative outcomes remain sobering since morbidity and mortality rates ranging from 25%-50% persist among modern published series. Some of the most impactful variation in rAAA management has been fostered by the rapid proliferation of endovascular repair (EVAR) along with service alignment at selected centers to improve timely revascularization. Indeed, clinical care pathways and emergency response networks are now increasingly utilized which has led to improved outcomes contemporaneously. Moreover, evolution in pre- and post-operative physiologic resuscitation has also contributed to observed improvements in rAAA outcomes. Due to different developments in care provision over time, the purpose of this review is to describe the modern management of rAAA, while providing historical perspectives on patient, procedure and systems-based practice elements that have evolved care delivery paradigms in this complex group of patients.

Time Distribution of Mortality After Ruptured Abdominal Aortic Aneurysm Repair

BACKGROUND

Ruptured abdominal aortic aneurysm (rAAA) repair is still associated with high mortality. The aim of this population-based study was to analyze the time distribution of mortality and short-term mortality trends after rAAA repair.

METHODS

This was a nationwide retrospective registry study including all patients (n = 3,927) who underwent endovascular (EVAR) (n = 935) or open surgical repair (OSR) (n = 2,992) for rAAA between 2000 and 2018. The National Patient Register was used as a source to extract patient and medical data. The register was cross-linked with the national all-cause mortality registry. The postoperative time of death was divided into <48 hours, 2 to 5 days, 6 to 10 days, 11 to 20 days, 21 to 30 days, and 31 to 90 days during the year intervals 2000-2004, 2005-2009, 2010-2014, and 2015-2018, respectively. The proportion of patients who died within each postoperative time interval was calculated.

RESULTS

The overall median age was 75.0 years (interquartile range [IQR] 69.0-80.0) and females were 19.6% (n = 769). The EVAR cohort was older (77 vs. 65 years; P < 0.001) and had significantly more cardiovascular risk factors and a history of malignancy. The overall postoperative 90-day mortality was 33.2%, EVAR 25.7%, and OSR 35.5%. There was an overall improvement in 90-day mortality over time (odds ratio [OR] 0.70; 95% confidence interval [CI] 0.57-0.87; P = 0.001) but not separately for EVAR or OSR. Analyzing all postoperative mortalities within 90 days, 43.4% of deaths occurred within 48 hours followed by 16.3% in 2-5 days. The distribution of mortality proportions in each time interval after OSR was 15.4% in < 48 hours, 7.3% in 2-5 days, 4.4% in 6-10 days, 8.6% in 11-30 days, and 6.0% in 31-90 days and after EVAR 11.1% < 48 hours, 3.6% 2-5 days, 3.1% 6-10 days, 4.6% 11-30 days, and 6% 31-90 days. The overall mortality proportions for patients who died <48 hours after aortic repair had decreased over time (P = 0.024). A logistic regression analysis found the following risk factors associated with mortality <48 hours after rAAA, open repair (OR 1.48; 95% CI 1.17-1.89; P = 0.001), female gender (OR 1.41; 95% CI 1.14-1.75; P = 0.002), and history of heart failure (OR 1.63; 95% CI 1.19-2.22; P = 0.002) or angina pectoris (OR 1.37; 95% CI 1.03-1.81; P = 0.03). The recent operative year interval, 2015-2018, was associated with a lower risk for mortality <48 hours (OR 0.72; 95% 0.53-0.98; P = 0.04) and <90-days (OR 0.63; 95% CI 0.49-0.80; P < 0.001).

CONCLUSIONS

Overall mortality after rAAA repair had decreased but early deaths remained a significant challenge. The mortality was highest within two days of surgery but the proportion of patients who died <48 hours after aortic repair had decreased in recent years. Open repair, female gender, and cardiovascular comorbidities were associated with mortality within 48 hours after surgery. More focused research in the early postoperative phase after rAAA is warranted.

Identification of Risk Factors and Development of Predictive Risk Score Model for Mortality after Open Ruptured Abdominal Aortic Aneurysm Repair

Background and Objectives: Despite the relatively large number of publications concerning the validation of these models, there is currently no solid evidence that they can be used with absolute precision to predict survival. The goal of this study is to identify preoperative factors that influenced 30-day mortality and to create a predictive model after open ruptured abdominal aortic aneurysm (RAAA) repair. Materials and Methods: This was a retrospective single-center cohort study derived from a prospective collected database, between 1 January 2009 and 2016. Multivariate logistic regression analysis was used to identify all significant predictive factors. Variables that were identified in the multivariate analysis were dichotomized at standard levels, and logistic regression was used for the analysis. To ensure that dichotomized variables were not overly simplistic, the C statistic was evaluated for both dichotomized and continuous models. Results: There were 500 patients with complete medical data included in the analysis during the study period. Of them, 37.6% were older than 74 years, and 83.8% were males. Multivariable logistic regression showed five variables that were predictive of mortality: age > 74 years (OR = 4.01, 95%CI 2.43−6.26), loss of consciousness (OR = 2.21, 95%CI 1.11−4.40), previous myocardial infarction (OR = 2.35, 95%CI 1.19−4.63), development of ventricular arrhythmia (OR = 4.54, 95%CI 1.75−11.78), and DAP < 60 mmHg (OR = 2.32, 95%CI 1.17−4.62). Assigning 1 point for each variable, patients were stratified according to the preoperative RAAA mortality risk score (range 0−5). Patients with 1 point suffered 15.3% mortality and 3 points 68.2% mortality, while all patients with 5 points died. Conclusions: This preoperative RAAA score identified risk factors readily assessed at the bedside and provides an accurate prediction of 30-day mortality after open repair of RAAA.

Influence of perioperative risk factors on the development of transmural colonic ischemia after open repair of ruptured abdominal aortic aneurysm

BACKGROUND

Development of colonic ischemia (CI) after ruptured abdominal aortic aneurysm (RAAA) treatment is a lethal complication with perioperative mortality reported to be high as 50%. Therefore, the main goal of this study was to identify pre-, intra- and postoperative risk factors associated with CI in patients undergoing open repair (OR) due to RAAA, that might help to select patients who are more prone to develop CI.

METHODS

This was a single-center prospective cohort study on patients with RAAA undergoing OR between January 1st 2018 and July 1st 2019, at the Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia. During this period 89 patients were treated due to RAAA and all were included in the study. The primary endpoint was grade III CI, or transmural necrosis, diagnosed by laparotomy.

RESULTS

Out of 89 patients operated due to RAAA, CI was diagnosed in 14 (15.73%). During the operation, patients with CI had a longer duration of hypotension (42.86±35.82 vs 24.13±23.48, p=.021) and more common significant hypotension (54.54% vs 14.66%, p=.024). In the postoperative course, patients with CI had more common signs of abdominal compartment syndrome (71.42% vs 25.33%, p=.001) and higher mortality rate (78.57% vs 29.33%, p=.001). The univariate regression model showed that one of the most significant factors that were associated with CI were age higher than 75 years, significant hypotension lasting more than one hour, organ lesion, development of abdominal compartment syndrome and higher potassium values on third and fourth quartile.

CONCLUSIONS

Grade III colon ischemia (transmural) remains the important cause of mortality after ruptured abdominal aortic aneurysm repair. We identified pre- and intraoperative and postoperative risk factors that could improve the selection of patients for primary open abdomen treatment or early exploratory laparotomy in order to prevent or timely diagnose colon ischemia.

Open Surgical Treatment of Acute Spontaneous Isolated Abdominal Aortic Dissection

BACKGROUND

The aim of this paper is to report our single-center experience in the open surgical treatment of acute spontaneous infrarenal isolated abdominal aortic dissection (siIAAD).

METHODS

This was a single center retrospective study. Between January 2015 and 2020 ten patients were treated due to acute siIAAD with open surgery. There were no patients treated for chronic siIAAD in this time period. Patients who had concomitant thoracic aortic involvement were excluded from this report.

RESULTS

The group consisted of 7 male and 3 female patients. History of hypertension was present in nine patients and six were active smokers. The abdominal/back pain was described in 9 patients, two had acute limb ischemia and three had aortic rupture. Median dissection length was 91 mm (65.7 - 106), median distance from the lowest renal artery was 30 mm (20.7 - 49.3) and median abdominal aortic diameter was 58.5 mm (32.5 - 66.2). Supracoeliac clamp was used in three cases with a ruptured aorta and suprarenal in two patients. The mean duration of proximal clamping time was 24.3 ± 7.49 min. One patient died of postoperative acute myocardial infarction, one suffered nonfatal pulmonary embolism and one had deep venous thrombosis. No aortic-related deaths and/or reinterventions occurred during the median follow-up of 32 months.

CONCLUSIONS

Acute siIAAD is a rare event which affects mostly male smokers with hypertension. Open surgery is a technically demanding procedure with acceptable complication rates and should be performed in specialized high-volume centers for the treatment of aortic disease. Future efforts to establish a multicenter registry to evaluate the prevalence of the disease and treatment options could provide better and more comprehensive guidelines for the treatment of acute siIAAAD.

Open Surgery for Ruptured Abdominal Aortic Aneurysm - 38 Years Experience at an Academic Center in Chile

BACKGROUND

Few series of ruptured abdominal aortic aneurysm (RAAA) from Latin America have been published.

OBJECTIVES

To report the outcomes of RAAA treated with open surgical repair (OSR) in a University Hospital in Chile. Secondary objectives are the identification of prognostic factors and survival rates.

METHODS

Retrospective review of consecutive RAAA patients treated with OSR between September 1979 and December 2017. Medical records, diagnostic images, and follow-up details were obtained. Statistical methods include multiple logistic regression analysis.

RESULTS

One hundred and sixteen patients underwent OSR for RAAA. The average age was 72.3 years (54-95), 62.9% ≥ 70 years, and 81.9% male. Preoperative systolic pressure <90 mm Hg was present in 74 patients (63.8%), and 10 (8.6%) experienced cardiac arrest before surgery. Only 30.2% were known to have an AAA before rupture. The mean aortic diameter was 7.9 cm. Sixteen patients had juxtarenal aneurysms (13.8%). The rupture was intra or retroperitoneal in 111 cases (95.7%), there were 4 fistulas to neighboring veins and one into the duodenum. Reconstruction included tubular graft in 39.7% and bifurcated in 58.6%. The estimated mean blood loss was 3,456 ± 2,768 mL (median 3,000). Mean mechanical ventilation was 7.4 ± 12.0 days and hemodialysis requirement in 21.8%. Six patients died during surgery and other 24 during the first postoperative month or in hospital, for an overall mortality rate of 25.9%. Age ≥70 years (P < 0.01), blood pressure less than 90 mm Hg (P = 0.03) and dialysis (P < 0.01) were associated with higher 30-day mortality rates. The survival rate was 68.0, 65.3, 44.3, and 25.2% at 1, 2, 5, and 10 years, respectively.

CONCLUSIONS

EVAR for RAAA is not affordable in every country. Outcomes of open RAAA repair at our institution are similar to results reported recently for OSR by the USA and European Medical centers.

Short-term and midterm survival of ruptured abdominal aortic aneurysms in the contemporary endovascular era

OBJECTIVE

Endovascular aneurysm repair (EVAR) has been shown to reduce mortality in the emergent repair of ruptured abdominal aortic aneurysms (AAAs). However, long-term survival data for this group of patients are lacking with contemporary endovascular endografts. The purpose of this study was to evaluate both 30-day mortality rates and 1-year survival in patients undergoing emergent EVAR in a 43-facility hospital system with a quaternary referral center with an established ruptured aneurysm protocol.

METHODS

Retrospective analysis of patients captured prospectively in an Institutional Review Board-approved registry for patients treated emergently for AAA were reviewed between 2012 and 2017 was conducted. Primary outcome measures were 30-day mortality and 1-year survival for the entire group as well as for symptomatic and ruptured aneurysms. Data were analyzed using logistic regression survival curves, and a log-rank test was performed to compare survival between open and endovascular repair. Patients were evaluated on an intent-to-treat basis, and outcomes were evaluated in a multivariate model.

RESULTS

A total of 249 patients were referred as part of the protocol. Of these, 102 (41%) were treated emergently. Kaplan-Meier estimates of 30-day and 1-year survival were 64% and 53% for all patients, 58% and 46% for ruptured patients, and 86% and 81% for symptomatic patients. EVAR resulted in improved 30-day survival (64% vs 31%; odds ratio, 4.0; P = .03) and 1-year survival (40% vs 23%; odds ratio, 2.3; P = .4) over open repair. Significant predictors for 30-day mortality included hypotension (P = .0003), blood transfusion (P < .0001), length of stay (P = .0005), extravasation (P = .01), preoperative cardiopulmonary resuscitation (P = .04), open repair (P = .007), aortouni-iliac reconstruction (P = .008), and abdominal compartment syndrome (P = .007). Significant predictors for 1-year mortality included advanced age (P = .04), hypotension (P = .01), blood transfusion (P = .006), extravasation (P = .03), reintubation (P = .03), and abdominal compartment syndrome (P = .03). There were no differences in outcomes based on race, gender, or outside transfer. Peripheral arterial disease (P = .04), hypertension (P = .04), coronary artery disease (P = .03), and familial history of aneurysms (P = .05) were related to increased 30-day mortality. Peripheral arterial disease (P = .06) and coronary artery disease (P = .07) were nearly significant, with increased 1-year mortality.

CONCLUSIONS

EVAR is associated with improved survival compared with open repair in patients requiring emergent AAA repair. However, in the first year, there is a significant risk of death based on initial presentation as well as underlying comorbidities. To improve long-term survival, aggressive medical management and medical surveillance are warranted.