Outcome in patients requiring renal replacement therapy after open surgical repair for ruptured abdominal aortic aneurysm

Systematic review and meta-analysis of the risk of bowel ischemia after ruptured abdominal aortic aneurysm repair

OBJECTIVE

Outcomes after repair of ruptured abdominal aortic aneurysm (RAAA) have improved in the last decade. It is unknown whether this has resulted in a reduction of postoperative bowel ischemia (BI). The primary objective was to determine BI prevalence after RAAA repair. Secondary objectives were to determine its major sequelae and differences between open repair (OR) and endovascular aneurysm repair (EVAR).

METHODS

This systematic review (PROSPERO CRD42017055920) followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. MEDLINE and Embase were searched for studies published from 2005 until 2018. The methodologic quality of observational studies was assessed with the Methodological Index for Non-Randomized Studies (MINORS) tool. The quality of the randomized controlled trials (RCTs) was assessed with the Cochrane Collaboration's tool for assessing risk of bias. BI prevalence and rates of BI as cause of death, reoperation, and bowel resection were estimated with meta-analyses with a random-effects model. Differences between OR and EVAR were estimated with pooled risk ratios with 95% confidence intervals (CIs). Changes over time were assessed with Spearman rank test (ρ). Publication bias was assessed with a funnel plot analysis.

RESULTS

A total of 101 studies with 52,670 patients were included; 72 studies were retrospective cohort studies, 14 studies were prospective cohort studies, 12 studies were retrospective administrative database studies, and 3 studies were RCTs. The overall methodologic quality of the RCTs was high, but that of observational studies was low. The pooled prevalence of BI ranged from of 0.08 (95% CI, 0.07-0.09) in database studies to 0.10 (95% CI, 0.08-0.12) in cohort studies. The risk of BI was higher after OR than after EVAR (risk ratio, 1.79; 95% CI, 1.25-2.57). The pooled rate of BI as cause of death was 0.04 (95% CI, 0.03-0.05), and that of BI as cause of reoperation and bowel resection ranged between 0.05 and 0.07. BI prevalence did not change over time (ρ, -0.01; P = .93). The funnel plot analysis was highly suggestive of publication bias.

CONCLUSIONS

The prevalence of clinically relevant BI after RAAA repair is approximately 10%. Approximately 5% of patients undergoing RAAA repair suffer from severe consequences of BI. BI is less prevalent after EVAR than after OR.

Analysis of in hospital mortality and long-term survival excluding in hospital mortality after open surgical repair of ruptured abdominal aortic aneurysm

Purpose

The aim of this study was to confirm the factors that affect the mortality associated with the open surgical repair of ruptured abdominal aortic aneurysm (rAAA) and to analyze the long-term survival rates.

Methods

A retrospective review was performed on a prospectively collected database that included 455 consecutive patients who underwent open surgical repair for AAA between January 2001 and December 2012. We divided our analysis into in-hospital and postdischarge periods and analyzed the risk factors that affected the long-term survival of rAAA patients.

Results

Of the 455 patients who were initially screened, 103 were rAAA patients, and 352 were non-rAAA (nAAA) patients. In the rAAA group, 25 patients (24.2%) died in the hospital and 78 were discharged. Long-term survival was significantly better in the nAAA group (P = 0.001). The 2-, 5-, and 10-year survival rates of the rAAA patients were 87%, 73.4%, and 54.1%, respectively. Age (hazard ratio [HR], 1.05; 95% confidence interval [CI], 1.02–.08; P < 0.001) and aneurysm rupture (HR, 1.96; 95% CI, 1.12–.44; P = 0.01) significantly affected long-term survival.

Conclusion

Preoperative circulatory failure is the most common cause of death for in-hospital mortality of rAAA patients. After excluding patients who have died during the perioperative period, age is the only factor that affects the survival of rAAA patients.

Outcomes of surgeon-modified fenestrated-branched endograft repair for acute aortic pathology

OBJECTIVE

Open surgical repair for acute aortic pathologies involving the visceral vessels is associated with morbidity and mortality rates of 40% to 70% and 30% to 60%, respectively. Due to these poor outcomes, the application of fenestrated/branched endovascular aortic repair (F/B-EVAR) has been expanded in this setting; however, durability remains unknown. The purpose of this analysis was to describe outcomes after F/B-EVAR for acute aortic disease.

METHODS

A single center retrospective review of all F/B-EVARs for acute aortic disease was completed. Primary end points included mortality and reintervention-free survival. Secondary end points were patency and freedom from endoleak, as well as change in aneurysm diameter and estimated glomerular filtration rate. Life-tables were used to estimate end points, while mixed statistical models were used to determine aneurysm diameter change.

RESULTS

Thirty-seven patients (mean age ± standard deviation, 67 ± 10 years; 75% male) underwent F/B-EVAR for acute aortic disease, and median follow-up time was 10.3 months (range, 0.5-31.4 months). Indications included thoracoabdominal aneurysm (65%; n = 24), pararenal aneurysm (17%; n = 6), postsurgical anastomotic pseudoaneurysm (8%; n = 3), dissection (5%; n = 2), and penetrating ulcer (5%; n = 2). Mean preoperative aneurysm diameter was 7.3 ± 1.8 cm. All patients were American Society of Anesthesiologists class IV or IV-E, and 38% (n = 14) had history of aortic repair. There were 105 visceral vessels revascularized (celiac, 26; superior mesenteric artery, 29; renal, 50) and 24 (65%) patients underwent three- or four-vessel repair. Technical success was 92% (n = 34), with no intraoperative deaths and one conversion (3%). Median length of stay was 6 days (range, 2-60 days), and postoperative morbidity was 41% (n = 15; spinal cord ischemia, 14% [8% permanent]; pulmonary, 14%; renal, 14%; extremity ischemia, 8%; stroke, 5%; cardiac, 3%; bleeding, 3%) with 30-day mortality of 19% (n = 7; in-hospital, 8%; n = 3). Endoleak was detected at some point in follow-up in 27% (n = 10), and a majority were type II (n = 7). Six (16%) patients underwent reintervention, and no late conversions occurred. Postoperative imaging was available in 27 (73%), and one celiac fenestration lost patency at 12 months. One-year branch vessel patency and freedom from reintervention was 98% ± 6% and 70% ± 9%, respectively. Estimated 1- and 4-year survival were 70% ± 8% and 67% ± 8%, respectively. During follow-up, aortic diameter decreased 0.5 cm (95% confidence interval, 1.1-0.2; P = .1) while estimated glomerular filtration rate decreased by 2 mL/min/1.73 m(2).

CONCLUSIONS

F/B-EVAR can be performed to treat a variety of symptomatic and/or ruptured paravisceral aortic pathologies. Perioperative morbidity and mortality can be significant; however, it is less than literature-based outcomes of open repair. Short-term fenestrated/branched graft patency is excellent, but reintervention is frequent, highlighting the need for diligent follow-up. Patients surviving the initial hospitalization for F/B-EVAR of acute aortic disease can anticipate good long-term survival.

Incidence and Outcomes of Severe Renal Impairment Following Ruptured Abdominal Aortic Aneurysm Repair

INTRODUCTION

Acute kidney injury (AKI) following ruptured abdominal aortic aneurysm (rAAA) repair is common and multifactorial. A standard definition of AKI after endovascular repair (EVAR), the Aneurysm Renal Injury Score (ARISe), has been proposed to facilitate standardised reporting and thus improve understanding of this issue.

METHODS

Data were collected retrospectively on AKI in a prospectively maintained database of all patients treated for rAAA in a single tertiary referral centre since the availability of routine out of hours emergency EVAR. The ARISe score was used to describe the degree of AKI and factors which correlated with poor renal outcomes were assessed.

RESULTS

Two-hundred and five patients were treated between January 2006 and April 2014. Of these, 125 were treated with open repair (OSR) and 80 were treated with EVAR. Severe AKI (defined as ARISe score ≥3) occurred in 36% of patients. After correction for confounders, patients treated with OSR were significantly more likely to develop severe AKI (43% vs. 26%, p = .02). There was no significant difference in preoperative serum creatinine between groups, but increased preoperative serum creatinine was strongly associated with severe AKI postoperatively (p < .001). Age, sex, endograft type, and preoperative CT scanning were not associated with differences in renal outcomes. Clamp position above renal arteries was predictive of severe AKI in patients treated with OSR (p < .01). Patients suffering severe AKI had significantly higher mortality at 30 days and 12 months (28% vs. 5% and 44% vs. 13%, p < .001 for both comparisons).

CONCLUSION

Severe AKI is common following successful repair of rAAA. In this large case series of high-risk patients, OSR was associated with significantly higher rates of severe AKI compared with EVAR, despite the increased dose of contrast involved in EVAR and the older age of these patients. In turn, severe AKI was associated with higher mortality rates.

Acute kidney injury defined according to the 'Risk,' 'Injury,' 'Failure,' 'Loss,' and 'End-stage' (RIFLE) criteria after repair for a ruptured abdominal aortic aneurysm

OBJECTIVE

Acute kidney injury (AKI) is a serious complication after repair of a ruptured abdominal aortic aneurysm (RAAA). In the present Society for Vascular Surgery (SVS)/International Society for CardioVascular Surgery (ISCVS) reporting standards patients are classified as no dialysis (grade I), as temporary dialysis (grade II), and as permanent dialysis or fatal outcome (grade III). However, AKI is a broad clinical syndrome including more than the requirement for renal replacement therapy. The recently introduced 'Risk,' 'Injury,' 'Failure,' 'Loss,' and 'End-stage' (RIFLE) classification for AKI comprises three severity categories based on serum creatinine and urine output ('Risk,' 'Injury,' and 'Failure'). The objective of the present study was to assess the incidence of AKI using the RIFLE criteria (AKIRIFLE). Secondary objectives were to assess the incidence of AKI as defined using the SVS/ISCVS reporting standards (AKISVS/ISCVS) and the association between AKIRIFLE and death.

METHODS

This was an observational cohort study in 362 consecutive patients with an RAAA in three hospitals in Amsterdam (The Netherlands) between 2004 and 2011. The end points were the incidence of AKIRIFLE, of AKISVS/ISCVS, and the combined 30-day or in-hospital death rate. A multivariable logistic regression model was made to assess the association between AKIRIFLE and death after adjustment for preoperative shock profile (Glasgow Aneurysm Score) and postoperative shock profile (Acute Physiology and Chronic Health Evaluation [APACHE] II score, use of vasopressors, and fluid balance during the first 24 hours after intervention).

RESULTS

AKIRIFLE occurred in 74% (267/362; 95% confidence interval [CI], 69%-78%), with 27% of these patients categorized as 'Risk' (71/267; 95% CI, 22%-32%), 39% categorized as 'Injury' (104/267, 95% CI, 33%-45%), and 34% categorized as 'Failure' (92/267; 95% CI, 29%-40%). AKISVS/ISCVS occurred in 48% (175/362; 95% CI, 43%-53%), with 53% of these categorized as 'grade I' (92/175; 95% CI, 45%-60%), 19% as 'grade II' (34/175; 95% CI, 14%-26%), and 28% as 'grade III' (49/175; 95% CI, 22%-35%). After multivariable adjustment for shock profiles the risk of dying in patients categorized as AKIRIFLE 'Failure' was greater than in patients without AKIRIFLE (adjusted odds ratio, 6.360; 95% CI, 2.231-18.130).

CONCLUSIONS

The incidence of AKI defined according to the RIFLE criteria (74%) was greater than defined using the SVS/ISCVS reporting standards (48%) and patients categorized as 'Failure' using the RIFLE criteria had a greater risk of dying than patients without AKI. These results indicate that the problem of AKI is much bigger than previously anticipated and that minimizing injury to the kidney could be an important focus of future research on reducing the death rate after RAAA repair.

Risk factors and outcomes associated with acute kidney injury following ruptured abdominal aortic aneurysm

Background

Current data describing the epidemiology of acute kidney injury (AKI) following repair of ruptured abdominal aortic aneurysm (rAAA) are limited and long-term outcomes are largely unknown. Our objectives were to describe the incidence rate, risk factors, clinical course and long-term outcomes of AKI following rAAA repair.

Methods

Retrospective population-based cohort study of all referrals undergoing emergency repair of rAAA in Northern Alberta from January 1, 2002 to December 31 2009. Demographic, clinical, physiologic and laboratory data were extracted. AKI was defined and classified according to the AKIN criteria.

Results

In total, 140 patients survived to receive emergent rAAA repair. Post-operative AKI occurred in 75.7% of patients (n = 106), 78.3% (n = 83) of which occurred during the initial 24 hours of ICU admission. AKIN stage 1, 2, and 3 occurred in 47 (33.6%), 36 (25.7%) and 23 (16.4%), respectively, with 19 patients receiving renal replacement therapy (RRT). Several clinical and biochemical patient factors were associated with incident AKI, including baseline estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m² (odds ratio [OR] 2.94; 95% CI, 1.15-7.51, p = 0.03), need for mechanical ventilation (OR 22.7; 95% CI, 7.0-72.1, p < 0.0001) and vasoactive therapy (OR 9.9; 95% CI, 3.0-32.2, p < 0.0001) and higher mean APACHE II scores (25.7 [8.2] vs. 16.3 [4.9], p < 0.0001). AKI was associated with a higher ICU (28.3% vs. 0%; p = 0.0008) and in-hospital case-fatality rate (35.9% vs. 0%, p = 0.0001). Of 102 survivors to discharge, 65.7% (n = 67) recovered to baseline kidney function. In multivariable analysis, greater severity of AKI (OR 5.01; 95% CI, 2.34-10.7, p < 0.001) and lower baseline eGFR (OR 0.96; 95% CI, 0.93-0.99, p = 0.03) were associated with non-recovery. AKI remained independently associated with 1-year mortality after adjusting for age, sex, comorbidity, and illness severity (OR 5.21; 95% CI, 1.04-26.2, p = 0.045; AUC 0.83; H-L GoF, p = 0.26). Among survivors at 1-year, only 63.4% (n = 55) had complete kidney recovery.

Conclusions

Following rAAA repair, AKI is a common complication independently associated with long-term post-operative mortality. A significant proportion of AKI sufferers in this setting fail to recover to baseline kidney function.

Predictors of postoperative mortality of ruptured abdominal aortic aneurysm: a retrospective clinical study

PURPOSE

Despite significant improvements in surgery, anesthesia, and postoperative critical care, the postoperative mortality rate of ruptured abdominal aortic aneurysm (RAAA) has remained at 40% to 50% for several decades. Therefore, we evaluated factors associated with the postoperative mortality of RAAA.

MATERIALS AND METHODS

From January 1999 to December 2008, a retrospective study was performed with 34 patients who underwent open repair of RAAA. The preoperative factors included age, sex, smoking, comorbidities, serum creatinine, hemoglobin, shock, pulse rate, and time from emergency room to operation room. The intraoperative factors included blood loss, transfusion, aortic clamping site and time, aneurysmal characteristics, rupture type, graft type, hourly urine output (HUO), and operative time. The postoperative factors included inotropic support, renal replacement therapy (RRT), reoperation, bowel ischemia, multiple organ failure (MOF), and intensive care unit stay. The 2-day and the 30-day mortality rates were analyzed separately.

RESULTS

The 2-day and the 30-day mortality rates were 14.7% and 41.2%, respectively. On univariate analysis, shock, transfusion, HUO, inotropic support and MOF for the 2-day mortality and serum creatinine, transfusion, aortic clamping site, HUO, inotropic support, RRT and MOF for the 30-day mortality were statistically significant. On multivariate analysis, shock, inotropic support and MOF for the 2-day mortality and aortic clamping site, RRT and MOF for the 30-day mortality were statistically significant.

CONCLUSION

To decrease the postoperative mortality rate of RAAA, prevention of massive hemorrhage and acute renal failure with infrarenal aortic clamping, as well as prompt operative control of bleeding and maintenance of systemic perfusion are important.

Outcome after open repair of ruptured abdominal aortic aneurysm in patients>80 years old: a systematic review and meta-analysis

BACKGROUND

The role of open repair in the management of ruptured abdominal aortic aneurysm (RAAA) in patients>80 years old is questioned by the perceived high operative risk of these patients. This issue has been investigated in the present meta-analysis of observational studies.

METHODS

Studies on open repair of RAAA in patients>80 years old were identified in July 2010. The immediate and intermediate results were expressed as pooled proportions with 95% confidence interval (95% CI). Linear regression and meta-regression were performed to evaluate the impact of variables on the immediate postoperative mortality.

RESULTS

Pooled analysis of 29 studies showed that the risk of immediate postoperative mortality in patients>80 years old was significantly higher than in younger patients (risk ratio 1.440, 95%CI 1.365-1.519, I2 36.8%, P=0.002; risk difference 19.4%, 95% CI 16.4-22.4%, I2 38.8%, P=0.019). Pooled analysis of 36 studies showed an immediate postoperative mortality rate of 59.2% (95% CI 55.7-62.5, I2 35.62). Immediate postoperative mortality in patients<80 years old positively correlated with that of patients>80 years old (rho: 0.686, P<0.0001). Intermediate survival data of 111 operative survivors were available from six studies, and their pooled survival rates at 1-, 2-, and 3-year were 82.4, 75.6, and 68.7%, respectively.

CONCLUSIONS

Immediate and intermediate survival rates of patients>80 years old after open repair of RAAA are acceptable. These findings suggest a more confident approach toward emergency repair of RAAA in the very elderly.

Acute renal failure requiring renal replacement therapy in the intensive care unit: impact on prognostic assessment for shared decision making

A 69-year-old female was receiving renal replacement therapy (RRT) for acute renal failure (ARF) in an intensive care unit (ICU). Consultation was requested from the palliative medicine service to facilitate a shared decision-making process regarding goals of care. Clinician responsibility in shared decision making includes the formulation and expression of a prognostic assessment providing the necessary perspective for a spokesperson to match patient values with treatment options. For this patient, ARF requiring RRT in the ICU was used as a focal point for preparing a prognostic assessment. A prognostic assessment should include the outcomes of most importance to a discussion of goals of care: mortality risk and survivor functional status, in this case including renal recovery. A systematic review of the literature was conducted to document published data regarding these outcomes for adult patients receiving RRT for ARF in the ICU. Forty-one studies met the inclusion criteria. The combined mean values for short-term mortality, long-term mortality, renal-function recovery of short-term survivors, and renal-function recovery of long-term survivors were 51.7%, 68.6%, 82.0%, and 88.4%, respectively. This case example illustrates a process for formulating and expressing a prognostic assessment for an ICU patient requiring RRT for ARF. Data from the literature review provide baseline information that requires adjustment to reflect specific patient circumstances. The nature of the acute primary process, comorbidities, and severity of illness are key modifiers. Finally, the prognostic assessment is expressed during a family meeting using recommended principles of communication.