Hospital Volume Matters: The Volume-Outcome Relationship in Open Juxtarenal AAA Repair.

OBJECTIVE: We studied whether the volume-outcome relationship would persist in more complex aortic operations. BACKGROUND: Despite the added complexity of the involvement of the renal arteries in open juxtarenal abdominal aortic aneurysm (AAA) repair, the volume effect in these difficult operations has yet to be defined. METHODS: We identified all patients in the Vascular Quality Initiative (VQI) who underwent open AAA repair from 2003 to 2016. We calculated each hospital's average annual volume for total open AAA repairs, and total open juxtarenal AAA repairs. We compared adjusted perioperative and long-term survival across quintiles of hospital volume, and constructed models including both volume metrics to evaluate the cross-volume effects. RESULTS: Of 8880 total open AAA repairs, there were 3470 open juxtarenal cases. Centers with low (<4), medium (4-14), and high (>14) volumes of open juxtarenal repair demonstrated adjusted perioperative mortality of 9.0%, 4.9%, and 3.9%, respectively (P < 0.01). When both volume metrics were considered, open juxtarenal volume, but not total open AAA volume was associated with perioperative mortality (lowest quintile of juxtarenal volume: OR 2.36 [1.29-4.30], P < 0.01). Hospital volume was not associated with adjusted long-term mortality. High volume centers were more likely to use renal protective strategies such as mannitol and cold renal perfusion (both P < 0.01). Low volume centers performed a similar proportion of cases each year, but 22 centers (13%) did stop performing repairs during the study period. CONCLUSION: Hospitals with low annualized volumes of open juxtarenal repair have higher perioperative mortality, irrespective of their total open aortic volume. Complex open AAA repairs should be performed at experienced centers, and future efforts should focus on centralization of complex aortic care.

Presentation, surgical intervention, and long-term survival in patients with Marfan syndrome.

OBJECTIVE: Patients with Marfan syndrome (MFS) often present with acute catastrophic aortic events at a young age and have a shortened life span. This study examines the impact of presentation and demographics on late survival in patients with MFS. METHODS: Adults with confirmed MFS in our thoracic aortic center dataset were identified and statistical analysis performed to identify the incidence and predictors of aortic interventions and late mortality. RESULTS: We identified 301 patients with a MFS initial diagnosis at age 17 years (interquartile range, 4-30 years) with presentation into our thoracic aortic center at 21 years (interquartile range, 8-34 years). The average follow-up in our center was 10 ± 10 years. Clinical features were 41% male, 86% white race, coronary artery disease 28%, hypertension 40%, peripheral vascular disease 19%, and anti-impulse agent in 51% (ß-blocker, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, calcium channel blocker). Distribution of operative aortic pathology was isolated to the ascending aorta (70%) and descending aorta (8%). One hundred seventy-eight patients (59%) required primary aortic surgery (36% emergent). Primary procedures were cardiac (aortic valve/root) in nature in 94%. Seventy-four patients (42%) required multiple aortic procedures at a mean of 9.2 ± 6.9 years, involving the thoracoabdominal aorta in 65%, thoracic aorta in 37%, and abdominal aorta in 21%. Patients who required multiple aortic procedures were more likely (P < .05) to have coronary artery disease (50% vs 30%), and peripheral vascular disease (43% vs 18%). Multiple aortic procedures were also more likely (P < .05) in patients who developed de novo distal dissection (14% vs 0%), had prior dissection (47% vs 18%), or unknown MFS at the time of the initial procedure (27% vs 63%). Multivariable analysis identified prior dissection as an independent predictor of need for emergent surgery (odds ratio, 13.20; 95% confidence interval, 4.64-37.30; P < .05), as well as additional aortic surgery (odds ratio, 4.42; 95% confidence interval, 1.87-10.50; P < .05). Kaplan-Meier analysis showed similar 10-year survival with or without aortic interventions (82% with vs 89% without; P = .08). Late survival was decreased in patients undergoing emergent initial procedures (66% vs 89%; P < .01), as well as those undergoing multiple operations (74% vs 86%; P = .03). CONCLUSIONS: These data indicate that, in the modern era, the mode of presentation and need for multiple procedures have a detrimental impact on late survival. Additionally, the presence of acute or chronic dissection predicts the need for additional aortic procedures during follow-up.

Aneurysm sac failure to regress after endovascular aneurysm repair is associated with lower long-term survival.

BACKGROUND: The early survival advantage of endovascular aneurysm repair (EVAR) compared with open repair reverses over time, possibly because of higher rates of reintervention related to endoleaks and aneurysm sac expansion. Therefore, we sought to examine the association between sac behavior, endoleaks, reintervention, and long-term survival. METHODS: We reviewed all patients undergoing EVAR in the Vascular Quality Initiative between 2003 and 2017 with an imaging study at 1 year postoperatively (±6 months). We defined aneurysm sac changes by Society for Vascular Surgery guidelines (change ≥5 mm) and determined independent predictors of sac behavior, new endoleak, and reintervention using hierarchical logistic regression. We employed Cox regression to examine the association between sac behavior and long-term survival. We performed propensity matching between patients with sac regression and those with failure to regress as a secondary analysis. RESULTS: Of 30,074 EVAR patients, 14,817 (49%) had a 1-year imaging study and were included in this study. At 1 year, 40% of sacs regressed, 35% remained stable, and 25% expanded. Factors independently associated with sac expansion were age (by decade: odds ratio [OR], 1.07; 95% confidence interval [CI], 1.01-1.13; P = .02), appearance of new endoleak (OR, 1.23; 95% CI, 1.10-1.37; P = .001), smaller aortic diameter (diameter <5 cm: OR, 1.37; 95% CI, 1.21-1.55; P < .001), anemia (OR, 1.47; 95% CI, 1.20-1.80; P < .001), rupture (OR, 1.33; 95% CI, 1.07-1.65; P = .01), and chronic kidney disease (OR, 1.15; 95% CI, 1.05-1.25; P < .01), whereas former smoking (OR, 0.86; 95% CI, 0.76- 0.96; P < .01), cerebrovascular disease (OR, 0.82; 95% CI, 0.67-0.99; P = .04), and statin therapy at discharge (OR, 0.83; 95% CI, 0.75-0.91; P < .001) were associated with lower risk of expansion. Both sac expansion (OR, 2.3; 95% CI, 2.0-2.7; P < .001) and a stable sac (OR, 3.1; 95% CI, 2.7-3.5; P < .001) were associated with the development of new endoleaks. Any failure of the aneurysm sac to regress was associated with long-term mortality compared with sac regression (stable sac size: hazard ratio, 1.2; 95% CI, 1.03-1.4; P = .02; sac expansion: hazard ratio, 1.6; 95% CI, 1.3-2.1; P < .001). This association persisted in patients without documented endoleaks and remained robust after accounting for reinterventions and endoleaks seen in follow-up or on completion angiography. In the propensity-matched cohort, patients with failure to regress experienced lower long-term survival (77% at 10 years compared with 82% for patients with sac regression; P = .01). CONCLUSIONS: After EVAR, aneurysm sac behavior is associated with the development of new endoleaks, reintervention, and long-term mortality. Not only sac expansion but any failure of the sac to regress is associated with higher long-term mortality, independent of reinterventions or endoleaks, and may be modified by statin therapy. Further study is needed to establish whether patients with stable sacs could benefit from selective reintervention.

Severe contralateral carotid stenosis or occlusion does not have an impact on risk of ipsilateral stroke after carotid endarterectomy.

OBJECTIVE: This study evaluates the impact of severe (>70%) contralateral carotid stenosis or occlusion (SCSO) on outcomes after carotid endarterectomy (CEA). METHODS: Clinical data for all patients undergoing CEA at a single center were prospectively gathered and retrospectively reviewed, with the sample population stratified according to the presence of SCSO. Perioperative outcomes of CEA in the presence of SCSO were analyzed using univariate and multivariate methods. RESULTS: During a 17-year study period, 2945 CEAs were performed on 1843 patients, including 736 (25%) patients with SCSO. Patients identified with SCSO had a higher rate of positive intraoperative electroencephalographic changes (30% vs 16%; P < .0001) and use of an intraoperative shunt (40% vs 28%; P < .0001). Univariate analysis identified SCSO as a risk factor for any stroke (2.8% vs 1.5%; P = .02), death (2.2% vs 1.1%; P = .02), and any stroke/death (4.3% vs 2.4%; P < .0079) but not ipsilateral stroke (1.5% vs 1.2%; P = .38). Multivariable regression demonstrated SCSO as an independent predictor of any stroke (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.0-3.3; P = .05) and any stroke/death (OR, 1.7; 95% CI, 1.1-2.7; P = .02), without increasing risk of ipsilateral stroke (OR, 1.3; 95% CI, 0.6-2.7; P = .54). The presence of SCSO was also associated with a higher risk of late mortality (hazard ratio, 1.3; 95% CI, 1.1-1.4; P < .01). CONCLUSIONS: Although the presence of SCSO is a risk factor for any stroke/death with CEA, it does not increase the risk of ipsilateral stroke. These data suggest that increased attention to perioperative medical and hemodynamic management should be especially considered in this cohort of patients as the observed strokes do not occur in the territory at risk from the surgical procedure.

Favorable impact of thoracic endovascular aortic repair on survival of patients with acute uncomplicated type B aortic dissection.

BACKGROUND: In uncomplicated type B aortic dissection (UTBAD), the "gold standard" has been nonoperative treatment with medical therapy, although this has been questioned by studies demonstrating improved outcomes in those treated with thoracic endovascular aortic repair (TEVAR). This study assessed long-term survival after acute UTBAD comparing medical therapy, open repair, and TEVAR. METHODS: The California Office of Statewide Hospital Planning Development database was analyzed from 2000 to 2010 for adult patients with acute UTBAD. Patients with nonemergent admission for aortic dissection, type A dissection, trauma, bowel ischemia, lower extremity ischemia, acidosis, or shock were excluded. The cohort was stratified by treatment type at index admission into medical therapy, open surgical repair, and TEVAR. Multivariable regression and survival analyses were used to evaluate the association of treatment type with long-term overall survival. RESULTS: There were 9165 cases, 95% medical therapy, 2% open repair, and 2.9% TEVAR. The mean age was 66 ± 15 years, with 39% female, 2.4% cocaine users, 18% with congestive heart failure, and 17% with Charlson Comorbidity Index >3. Mean inpatient costs were $57,000 for medical therapy, $200,000 for open repair, and $130,000 for TEVAR (P < .01). Inpatient mortality was 6.5% overall, 6.3% for medical therapy, 14% for open repair, and 7.1% for TEVAR (P < .01). One-year and 5-year survivals were 84% and 60% in medical therapy, 76% and 67% in open repair, and 85% and 76% in TEVAR (log-rank, P < .01). On risk-adjusted multivariable analysis, TEVAR had improved survival compared with medical therapy (hazard ratio, 0.68; 95% confidence interval, 0.6-0.8; P < .01), with no difference between open repair and medical therapy (hazard ratio, 1.0; 95% confidence interval, 0.8-1.3; P < .01). CONCLUSIONS: This statewide study on survival after acute UTBADs shows an independent survival advantage for TEVAR over medical therapy. These data add further evidence for a paradigm shift in acute management of type B dissection in favor of early TEVAR.

Early Experience with Fenestrated Endovascular Compared to Open Repair of Complex Abdominal Aortic Aneurysms in a High-Volume Open Aortic Center.

BACKGROUND: Early data suggest that fenestrated endovascular aneurysm repair (FEVAR) is feasible but may have higher morbidity and unclear durability compared to open surgical repair (OSR) of complex abdominal aortic aneurysms (CAAAs). We compared the early experience following elective FEVAR to traditional OSR of CAAA in a high-volume open aortic center. METHODS: All patients undergoing FEVAR and OSR for elective CAAA from 1/2010-7/2015 were identified. Univariate, multivariable logistic, and Cox hazards modeling were used to compare perioperative and intermediate outcomes. RESULTS: We identified 116 patients who underwent CAAA repair (18 FEVAR) with a median follow-up of 26 months. FEVAR patients had higher rates of congestive heart failure (22% vs. 5.1%; P = 0.03). Operative time was slightly longer following FEVAR (282 vs. 240 min, P = 0.02). There was no difference in 30-day operative mortality (0% in both) or major complications. Median intensive care unit (0 vs. 3 days; P < 0.001) and hospital length of stay (2.5 vs. 7 days; P < 0.001) were shorter after FEVAR. Rates of 30-day graft complications (5.6% FEVAR vs. 5.1% OSR, P = 1.0) were similar, and there was no statistically significant difference in rates of graft complications in follow-up (17% vs. 8.2%, P = 0.37). After multivariable modeling, FEVAR patients were more likely to develop late graft-related complications (hazard ratio [HR]; 5.0, 95% confidence interval [CI]: 0.98-25). Kaplan-Meier 1-year survival was similar (100% vs. 92%), even after multivariable adjustment (HR, 0.6; 95% CI: 0.1-5.0). CONCLUSIONS: Early experience in FEVAR at a high-volume open aortic center shows that FEVAR can be performed safely with comparable perioperative risk to OSR. FEVAR may be associated with graft complications during follow-up, which should be considered in clinical decision-making. Further study is warranted to better elucidate late durability of FEVAR and the impact of the learning curve on outcomes.

The Impact of Perioperative Ankle-Brachial Index and Clinical Status on Outcomes following Lower Extremity Bypass.

BACKGROUND: Ankle-brachial index (ABI) is a common method of graft surveillance after infrainguinal lower extremity bypass (LEB) surgery and is recommended by the Society for Vascular Surgery. Several studies failed to show the benefit of ABI surveillance but were limited by sample size, and the practice remains variable. METHODS: We identified all patients who underwent LEB for occlusive disease from the Vascular Study Group of New England Registry (VSGNE) between 2003 and 2016. Postoperative changes were defined as follows: improvement for ABI >0.15 at discharge or clinical status improved (i.e., symptoms improved from rest pain to asymptomatic, and so forth), no change if ABI was within 0.15 or no change in clinical status, or worsened if ABI decreased >0.15 or clinical status deteriorated. We determined the independent effect of these changes on rates of mortality, reintervention, patency loss, amputation, and Major Adverse Limb Events (MALE-above ankle amputation, revision, thrombectomy, or lysis). In addition, we compared the practice of perioperative ABI to follow-up without ABI using propensity scores with inverse probability weights. RESULTS: We identified 7,994 patients undergoing their first intervention in the VSGNE, 2,251 of whom (29%) had both preoperative and discharge ABIs. Overall, 5,369 (67%) of the bypasses used vein, and 4,539 (57%) were femoropopliteal, with no difference in the rate of vein use or bypass type between those who had discharge ABIs and those who did not (P > 0.05). Most bypasses were performed for chronic limb-threatening ischemia (59% in the ABI group, 65% in those without ABI data, P < 0.01 for difference). At discharge, ABI remained stable in 22%, improved in 69%, and worsened in 9%, whereas clinical status remained stable in 12%, improved in 77%, and worsened in 12%. In univariate analysis, clinical status was associated with mortality, amputation, and MALE, but ABI change was only associated with mortality (all P < 0.01). After multivariable adjustment, ABI change was no longer associated with mortality and remained unassociated with amputation and MALE (P > 0.05), and the addition of ABI change to the models did not improve the fit of the model (likelihood ratio P > 0.05). Forgoing perioperative ABI was associated with higher rates of patency loss (P = 0.02), but not reinterventions (P = 0.57), or untreated patency loss (P = 0.17). CONCLUSIONS: A change in clinical status, but not a change in ABI, was associated with adverse outcomes after LEB. In this group of VSGNE patients with follow-up, perioperative ABI did not add incremental value to clinical status alone as a method of graft surveillance.

Extended Motor Evoked Potentials Monitoring Helps Prevent Delayed Paraplegia After Aortic Surgery.

OBJECTIVE: Motor evoked potentials (MEPs) monitoring can promptly detect spinal cord ischemia (SCI) from aortic clamping during open thoracoabdominal aneurysm repair (OTAAR) with distal aortic perfusion (DAP) and thus help decrease the risk of immediate postoperative SCI (IP-SCI). However, neither stable MEPs during aortic clamp interval (ACI) nor absence of IP-SCI eliminate the possibility of delayed postoperative SCI (DP-SCI). We hypothesized that extension of MEPs monitoring beyond ACI can also help decrease the risk of DP-SCI. METHODS: We identified 150 consecutive patients at our institution between April 2005 and October 2014 who underwent OTAAR with DAP and MEPs monitoring and had no IP-SCI. Using logistic regression analysis, we studied the independent effect of extended MEPs monitoring on the risk of developing DP-SCI. We used a propensity score analysis to adjust for potential confounders, such as poorly controlled hypertension, previous aneurysm surgery, splenectomy, acute aortic dissection, aneurysm type, older age, and history of diabetes and smoking. RESULTS: From the 150 patients, 129 (86%) remained neurologically intact whereas 21 (14%) developed DP-SCI. Nineteen of these twenty-one patients (90%) had no extended monitoring. Fifty-seven of fifty-nine (97%) patients who benefited from extended monitoring had no DP-SCI (p = 0.003). Extended MEPs monitoring was independently associated with decreased risk of DP-SCI (odds ratio = 0.14; 95% confidence interval: 0.03, 0.65; p = 0.01). INTERPRETATION: MEPs detect the lowest systemic blood pressure that ensures appropriate spinal cord perfusion in the postoperative period. Thus, they inform the hemodynamic management of patients post-OTAAR, particularly in the absence of a reliable neurological exam.

Chronic Kidney Disease Class Predicts Mortality After Abdominal Aortic Aneurysm Repair in Propensity-matched Cohorts From the Medicare Population.

INTRODUCTION: Chronic kidney disease (CKD) predicts mortality after abdominal aortic aneurysm (AAA) repair. Few studies are adequately powered to stratify outcomes by CKD severity. This study assesses the effect of CKD severity on survival after AAA repair. METHODS: Patients who underwent AAA repair from 2006 to 2007 were retrospectively identified in the Medicare database and stratified by CKD class as follows: normal (CKD class 1 and 2), moderate (CKD class 3), and severe (CKD class 4 and 5). Propensity matching (30:1) by clinical factors and procedure type was performed to derive well-matched comparative cohorts. Primary outcomes were 30-day and long-term mortality; secondary outcomes included hospital length of stay and cost. RESULTS: A total of 47,715 patients were included (96.7% normal, 1.88% moderate, and 1.65% severe). Propensity matching was corrected for differences between cohorts. Thirty-day mortality was higher in moderate (5.7% vs normal 2.5%; P < 0.01) and severe (9.9% vs normal 1.8%; P < 0.01) groups. Hospital length of stay increased with CKD severity (4.4 ±â€Š3.7 days normal vs 6.5 ±â€Š4.2 days moderate CKD; P < 0.01/4.7 ±â€Š3.8 days normal vs 9.1 ±â€Š4.5 days severe CKD; P < 0.01) as did cost ($23 ±â€Š14K normal vs $25 ±â€Š16K moderate; P < 0.01 /$22 ±â€Š11K normal vs $29 ±â€Š22K severe; P < 0.01). Three-year survival favored the normal cohort (80% vs 64% moderate; log rank P < 0.01 /82% normal vs 44% severe; log rank P < 0.01). CONCLUSIONS: CKD severity is an important predictor of perioperative mortality and long-term survival after AAA repair in propensity-matched cohorts. The 5-fold increase in 30-day mortality and 44% in 3-year survival suggest that elective AAA repair is contraindicated in most severe CKD patients.

Perioperative and long-term impact of chronic kidney disease on carotid artery interventions.

OBJECTIVE: Chronic kidney disease (CKD) increases morbidity and mortality after vascular procedures and adversely affects late survival of patients. The presence of CKD also confers increased risk of stroke in patients with asymptomatic carotid stenosis. Patients undergoing carotid intervention in the Vascular Study Group of New England database were stratified by CKD status referable to periprocedural and late outcomes. METHODS: All carotid artery stenting and carotid endarterectomies (CEAs) performed from 2003 to 2013 were stratified by CKD severity as mild (estimated glomerular filtration rate [eGFR] >60 mL/min/1.73 m2), moderate (eGFR 30-59), and severe (eGFR <30). The impact of CKD on outcomes of carotid procedures was evaluated using univariate and multivariate methods. RESULTS: Of 12,568 patients identified, 11,746 (93%) underwent CEA and 822 (7%) underwent carotid artery stenting. Procedures were performed for symptomatic disease in 40%. CKD severity was mild in 58%, moderate in 35%, and severe in 7%. The 30-day stroke rate was very low across all CKD groups (1.76% mild vs 1.84% moderate and 1.34% severe; P = .009). The 30-day mortality increased with worsening renal function (0.4% mild vs 0.9% moderate and 0.9% severe; P = .01). Independent predictors of 30-day stroke or death included American Society of Anesthesiologists (ASA) class 4 or 5 (odds ratio, 2.3; 95% confidence interval [CI], 1.5-3.4; P = .0001). Multivariable Cox hazards regression showed that severe CKD (hazard ratio [HR], 1.8; 95% CI, 1.3-2.6), ASA class 4 or 5 (HR, 1.7; 95% CI, 1.3-2.2), preoperative cortical symptoms (HR, 1.5; 95% CI, 1.2-1.8), history of diabetes (HR, 1.4; 95% CI, 1.1-1.7), and age (HR, 1.03/y; 95% CI, 1.02-1.04) independently (all P < .01) predicted neurologic events or death at median follow-up of 12.7 months (interquartile range, 10.3-15.2 months). CKD did not increase the risk of neurologic events at 1-year follow-up. Predictors (P < .05) of late death included moderate CKD (HR, 1.3; 95% CI, 1.01-1.7), severe CKD (HR, 2.2; 95% CI, 1.6-2.9), ASA class 4 or 5 (HR, 1.6; 95% CI, 1.2-2.0), history of diabetes (HR, 1.4; 95% CI, 1.2-1.7), chronic obstructive pulmonary disease (HR, 1.4; 95% CI, 1.1-1.8), and cortical symptoms (HR, 1.3; 95% CI, 1.05-1.6). The 1-, 5-, and 10-year survival rates decreased with worsening renal function (log-rank test, P < .001), but patients with severe CKD maintained a 71% survival at 5 years. CONCLUSIONS: CKD severity increases risk of perioperative mortality as well as late mortality. Patients with CKD benefit from stroke-free survival especially after CEA. Unlike patients with peripheral arterial occlusive disease, for whom severe CKD reduces median survival to ∼2.5 years, patients with CKD and carotid disease exhibit much longer survival. This suggests that carotid interventions have utility in carefully selected patients with moderate and severe CKD, particularly in symptomatic disease.

Contemporary outcomes of open complex abdominal aortic aneurysm repair.

OBJECTIVE: The recent commercial availability of fenestrated stent grafts is likely to result in increasing endovascular repair of complex (juxtarenal and suprarenal) abdominal aortic aneurysms (cAAAs). Whereas most studies providing benchmarking for outcomes after open repair have been from high-volume centers, we sought to evaluate outcomes after elective open cAAA repair vs infrarenal AAA repair at a regional level. METHODS: We used the Vascular Study Group of New England registry, which recorded 1875 open AAA repairs in New England from 2003 to 2011. Data from 14 hospitals performing both AAA and cAAA repair were used to assess the impact of clinical and technical factors on outcomes of cAAA repair. RESULTS: There were 443 patients who had elective cAAA repair as defined by use of a suprarenal (n = 340; 77%) or supraceliac (n = 103; 23%) clamp, with median survival follow-up of 35 months (interquartile range, 47 months). Compared with AAA repair, patients undergoing cAAA repair were more likely to be female; to have hypertension, congestive heart failure, or chronic obstructive pulmonary disease; and to have a higher baseline creatinine concentration. cAAA cases were repaired through a retroperitoneal incision in 40% of cases, with hypothermic renal perfusion use in 15%, mannitol in 73%, and renal bypass in 13%, with wide variability in the application of these adjuncts. Complex aneurysm repair vs routine AAA repair was associated with a higher independent risk of 30-day mortality (3.6% vs 1.2%; P = .002), respiratory complications (19% vs 10%; P < .001), and renal complications (21% vs 8.7%; P < .001). Among all patients, the only independent clinical or technical predictors of 30-day mortality were preoperative coronary artery disease (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.1-5.4; P = .02) and amount of intraoperative blood transfusion (OR, 2.8; 95% CI, 1.3-6.2; P = .01). In the subgroup undergoing cAAA repair, there were no predictors of operative mortality. Renal or visceral ischemia time was the only technical factor during cAAA repair that independently predicted cardiac (OR, 1.01; 95% CI, 1.00-1.03; P = .04), respiratory (OR, 1.03; 95% CI, 1.01-1.04; P < .001), and renal (OR, 1.03; 95% CI, 1.02-1.05; P < .001) complications. Long-term survival for cAAA patients was 91% ± 1% at 1 year and 71% ± 3% at 5 years and not different from that of patients undergoing infrarenal AAA repair. Risk-adjusted predictors of late mortality after cAAA repair included age (hazard ratio [HR], 1.08; 95% CI, 1.04-1.11; P < .001), chronic obstructive pulmonary disease (HR, 1.9; 95% CI, 1.2-3.0; P = .008), and preoperative creatinine concentration (per mg/dL; HR, 1.8; 95% CI, 1.05-2.9; P = .03). CONCLUSIONS: These data highlight excellent operative outcomes for open cAAA repair across the New England region despite significant variation in operative conduct across hospitals. Patients tolerating cAAA repair have durable long-term survival.

Applicability of the Society for Vascular Surgery's Objective Performance Goals for Critical Limb Ischemia to Current Practice of Lower-Extremity Bypass.

BACKGROUND: In 2009, the Society for Vascular Surgery (SVS) established objective performance goals (OPGs) for critical limb ischemia (CLI) based on data from previous, randomized, controlled trials of lower-extremity bypass (LEB). These OPG sought to establish a benchmark of outcomes to which one could compare future endovascular therapy. However, the cohort used to develop the OPG excluded all patients who required prosthetic conduit and those with end-stage renal disease (ESRD), possibly limiting the generalizability of these results and the subsequent guidelines. The goal of this study was to determine if the SVS OPG are applicable to the current population of patients undergoing LEB. METHODS: All patients who underwent infrainguinal LEB for CLI from January 2010 to December 2013 were identified in a prospectively maintained database. Patients were stratified into OPG eligible and ineligible (non-OPG) groups based on their demographic and operative characteristics. OPG eligible patients were further stratified into high risk and average risk. Outcomes included 30-day major adverse limb events (MALEs), 30-day major adverse cardiovascular events (MACE), 1-year survival, and 1-year freedom from amputation. RESULTS: A total of 89 individual patients were identified. Only 43 (48%) patients met OPG inclusion criteria and 46 (52%) were not OPG eligible (non-OPG). The 30-day MALE was 8.7% (13.0% non-OPG vs. 7.0% OPG, P = 0.34). The 30-day MACE was 11.2% (13.0% non-OPG vs. 9.3% OPG, P = 0.58). One-year survival was 80.3% ± 4.5% (71.2% non-OPG vs. 90.0% OPG, P = 0.21). One-year freedom from amputation was 71.7% ± 5.5% (58.8% non-OPG vs. 84.0% OPG, P = 0.03). CONCLUSIONS: The SVS OPG for LEB are likely not generalizable to current practice as 51% of patients would have been excluded from the SVS cohort because of ESRD and prosthetic conduit. Most SVS OPG (30-day MALE, 1-year survival, and 1-year limb salvage) were attainable in patients who met SVS OPG inclusion criteria; but for the patients who are not OPG eligible, new benchmarks are needed.

Postoperative renal dysfunction independently predicts late mortality in patients undergoing aortic reconstruction.

OBJECTIVE: Preoperative chronic kidney disease (CKD) has been shown to predict postoperative renal complications and mortality after open aortic surgery; the impact of postoperative renal complications less severe than permanent dialysis are unknown. We evaluated the impact of postoperative renal dysfunction severity on survival using a regional quality improvement registry. METHODS: Patients undergoing intact open aortic reconstruction in the Vascular Study Group of New England registry (2003-2012) were stratified by severity of postoperative renal complications; none, creatinine increase of greater than 0.5 mg/dL (incCr), or any hemodialysis (HD). Predictors of renal dysfunction and impact of renal complications on survival were analyzed using multivariable methods. RESULTS: We included 2695 patients, of which 65% (n = 1733) underwent open abdominal aortic aneurysm repair, and 35% (n = 962) open aortoiliac reconstruction. At baseline, 15% of patients had preoperative moderate CKD and 1.2% had severe CKD. Postoperative renal complications of incCr occurred in 8.5% of patients, and 1.5% required HD. Multivariable cumlogit regression identified severe baseline CKD (odds ratio [OR], 15; 95% confidence interval [CI], 6.4-34; P < .001, moderate CKD (OR, 2.8; 95% CI, 1.9-3.3; P < .001), suprarenal clamp use (OR, 2.2; 95% CI, 1.6-2.9; P < .001), perioperative vasopressor requirements (OR, 2.2; 95% CI, 1.6-2.9; P < .001), operating time (OR, 1.004 per minute; 95% CI, 1.003-1.006; P < .001), and chronic obstructive pulmonary disease (OR, 1.5; 95% CI, 1.2-1.8; P < .001) as independent predictors of worsening strata of postoperative renal dysfunction. Multivariable logistic regression analysis showed that patient age (OR, 1.06 per year; 95% CI, 1.01-1.1; P = .01), baseline chronic obstructive pulmonary disease (OR, 1.6; 95% CI, 1.2-2.2; P < .01), incCr (OR, 3.7; 95% CI, 1.8-7.4; P = .009), and HD (OR, 4.8; 95% CI, 1.8-12.7); P = .009) independently increased 30-day mortality. Risk-adjusted multivariable Cox regression showed that incCr (hazard ratio, 1.8; 95% CI, 1.3-2.6; P < .001) and HD (hazard ratio, 4.4; 95% CI, 2.8-6.9; P < .001) increased risk of late death independent of a variety of other clinical variables, including baseline CKD. The 5-year survival was lower (log-rank P < .001) in patients with incCr (66% ± 4%), and HD (38% ± 10%) compared with those with no renal complications (77% ± 1%). CONCLUSIONS: Increasing severity of postoperative renal dysfunction independently predicts increased risk of late mortality after open aortic surgery. Perioperative measures to decrease renal complications may potentially prolong the survival of patients after open aortic surgery.

Further experience with distal aortic perfusion and motor-evoked potential monitoring in the management of extent I-III thoracoabdominal aortic anuerysms.

BACKGROUND: Prior studies indicated improved early mortality and paraplegia rates in a small cohort of patients with type I-III thoracoabdominal aortic aneurysms (TAAs) treated with atriofemoral bypass (AFB) and motor-evoked potentials (MEVPs) when compared with a propensity-matched cohort of patients treated with the clamp and sew (CS) method, wherein epidural cooling was the principal spinal cord protective adjunct. The use of AFB/MEVP increases the complexity of TAA repair and in this study, we address whether the early benefits will be sustained when this is applied to a general population with type I-III TAAs. METHODS: Consecutive patients undergoing repair of nonruptured Crawford extent I-III TAAs from 1/1987 to 12/2011 were identified. Patients were stratified according to operative approach (AFB/MEVP vs CS). Endpoints included long-term survival, and the composite outcome of perioperative death and paraplegia. A multivariate, risk-adjusted model was then created to determine if operative approach independently influenced outcome. RESULTS: There were 485 patients (CS = 385 [79%]; AFB/MEVP = 100 [21%]). The cohorts differed in that the AFB/MEVP group was younger (65.8 ± 12.5 years vs 70.9 ± 9.7 years; P < .001), had more extent I/II aneurysms (66% vs 50.1%; P = .005), and had more chronic dissections (30.3% vs 18.9%; P = .018). Operative variables differed in that the AFB/MEVP cohort had longer operative times (434 ± 112 minutes vs 324 ± 98 minutes; P < .001) and higher blood turnover (6028 ± 3473 mL vs 3581 ± 3111 mL; P < .0001). There was no difference in the rate of intraoperative death (AFB/MEVP = 1.0% vs CS = 0.5%; P = .50), length of intensive care unit stay (AFB/MEVP = 9.6 ± 8.6 days vs CS = 9.5 ± 12.3 days; P = .95) or hospital length of stay (AFB/MEVP = 19.9 ± 12.6 days vs CS = 21.6 ± 23.5 days; P = .49). The composite perioperative death and paraplegia rate was lower in the AFB/MEVP cohort (7% vs 19%; P = .004). The multivariate model for predictors of the composite outcome showed that AFB/MEVP was protective (odds ratio, 0.39; 95% confidence interval, 0.17-0.9; P = .028). Long-term (4-year) survival was improved in the AFB/MEVP group as well (73 ± 6% vs 60 ± 3%; P = .004). CONCLUSIONS: AFB/MEVP is an independent predictor of improved perioperative death and paraplegia rates as well as long-term survival in patients undergoing repair of type I-III TAAs and is the preferred operative strategy.

Impact of chronic kidney disease on outcomes after abdominal aortic aneurysm repair.

OBJECTIVE: Chronic kidney disease (CKD) is associated with increased morbidity and death after open abdominal aortic aneurysm (AAA) repair (OAR). This study highlights the effect of CKD on outcomes after endovascular AAA (EVAR) and OAR in contemporary practice. METHODS: The National Surgical Quality Improvement Program (NSQIP) Participant Use File (2005-2008) was queried by Current Procedural Terminology (American Medical Association, Chicago, Ill) code to identify EVAR or OAR patients, who were grouped by CKD class as having mild (CKD class 1 or 2), moderate (CKD class 3), or severe (CKD class 4 or 5) renal disease. Propensity score analysis was performed to match OAR and EVAR patients with mild CKD with those with moderate or severe CKD. Comparative analysis of mortality and clinical outcomes was performed based on CKD strata. RESULTS: We identified 8701 patients who were treated with EVAR (n = 5811) or OAR (n = 2890) of intact AAAs. Mild, moderate, and severe CKD was present in 63%, 30%, and 7%, respectively. CKD increased (P < .01) overall mortality, with rates of 1.7% (mild), 5.3% (moderate), and 7.7% (severe) in unmatched patients undergoing EVAR or OAR. Operative mortality rates in patients with severe CKD were as high as 6.2% for EVAR and 10.3% for OAR. Severity of CKD was associated with increasing frequency of risk factors; therefore, propensity matching to control for comorbidities was performed, resulting in similar baseline clinical and demographic features of patients with mild compared with those with moderate or severe disease. In propensity-matched cohorts, moderate CKD increased the risk of 30-day mortality for EVAR (1.9% mild vs 3.2% moderate; P = .013) and OAR (3.1% mild vs 8.4% moderate; P < .0001). Moderate CKD was also associated with increased morbidity in patients treated with EVAR (8.3% mild vs 12.8% moderate; P < .0001) or OAR (25.2% mild vs 32.4% moderate; P = .001). Similarly, severe CKD increased the risk of 30-day mortality for EVAR (2.6% mild vs 5.7% severe; P = .0081) and OAR (4.1% mild vs 9.9% severe; P = .0057). Severe CKD was also associated with increased morbidity in patients treated with EVAR (10.6% mild vs 19.2% severe; P < .0001) or OAR (31.1% mild vs 39.6% severe; P = .04). CONCLUSIONS: The presence of moderate or severe CKD in patients considered for AAA repair is associated with significantly increased mortality and therefore should figure prominently in clinical decision making. The high mortality of AAA repair in patients with severe CKD is such that elective repair in such patients is not advised, except in extenuating clinical circumstances.

Comparable mortality with open repair of complex and infrarenal aortic aneurysm.

BACKGROUND: A consequence of endovascular aneurysm repair (EVAR) of anatomically straightforward infrarenal abdominal aortic aneurysm repair cohort (AAA) is that open aneurysm repair is more commonly performed for complex anatomy. Complex aneurysm repair with visceral vessel involvement (CAA) or combined aneurysm repair and visceral vessel reconstruction (VVR) has traditionally been considered to increase morbidity and mortality compared with repair of infrarenal AAA. This study evaluated contemporary outcomes of open abdominal aneurysm surgery, including AAA, CAA, and VVR using the National Surgical Quality Improvement Program (NSQIP) database. METHODS: The NSQIP Participant Use File was queried by CPT code to identify patients undergoing AAA, CAA, and VVR (2005-2008). Comparative analysis of clinical features, technical details and 30-day outcomes was performed using univariate methods. Logistic regression analysis was used to identify predictors of morbidity and mortality. RESULTS: A total of 2820 patients underwent AAA and 592 CAA. Renal insufficiency (ie, creatinine >1.4 mg/dL) rates were similar in AAA and CAA patients, however, more frequent in patients with VVR (51% vs 31% [no bypass]; P < .01). CAA was less likely to be performed urgently (6.3% vs 9.1%; P < .05) and was associated with increased operative time (254 ± 100 vs 224 ± 93; P < .01) compared with AAA. Univariate analysis showed that CAA did not increase mortality (5.7% vs 5.1%; P = .5). CAA slightly increased overall complications (32% vs 27%; P = .01) compared with AAA. 73 (2.5%) AAA and 84 (12%) CAA patients had simultaneous VVR and these patients exhibited a trend toward increased mortality (8.9% vs 5.2%; P = .07). VVR increased complications (43% (VVR) vs 26% [no bypass]; P < .01), including ventilation >48 hours (21% [VVR] vs 12% [no bypass]; P < .01), renal failure (7.6% [VVR] vs 4.1% [no bypass]; P = .04), and sepsis (13% [VVR] vs 6.3% ([no bypass]; P < .01). Multivariate analysis demonstrated that CAA (odds ratio [OR], 1.3 [95% confidence interval (CI), 1.1-1.6]; P = .01) and VVR (OR, 2.2 [95% CI, 1.8-3.6]; P < .01) increased the odds of any complication. Independent predictors of mortality included dependent functional status (OR, 3.6 [95% CI, 2.3-5.4]; P < .01), elevated pre-op creatinine (OR, 2.9 [95% CI, 2.2-4.0]; P < .01), type II diabetes (OR, 1.6 [95% CI, 1.05-2.4]; P = .03), and age (OR, 1.06 [95% CI, 1.03-1.08]; P < .01). Neither CAA (OR, 1.2 [95% CI, 0.84-1.8]; P = .3) nor VVR (OR, 1.6 [95% CI, 0.89-2.9]; P = .11) were associated with increased mortality compared with AAA. CONCLUSION: In contemporary practice the migration of open repair to increasingly complex cases has been achieved with 30-day mortality essentially equivalent to open repair of infrarenal AAA. Patients who require VVR do sustain increased complications, in particular renal failure. These data also emphasize the importance of baseline renal insufficiency in clinical decision making. CAA and VVR are associated with increased morbidity in comparison to AAA repair; however, both procedures can be safely performed in patients without increased risk of operative mortality.

Preoperative functional status predicts perioperative outcomes after infrainguinal bypass surgery.

OBJECTIVE: Infrainguinal surgical bypass (BPG) is a durable method for lower extremity revascularization, but is accompanied by significant 30-day morbidity and mortality (MM). The goal of this study is to relate preoperative functional status, a defined metric in the National Surgical Quality Improvement Program (NSQIP) database, to perioperative MM. METHODS: Between January 1, 2005 and December 31, 2007, all patients who underwent BPG from the NSQIP private sector database were reviewed. The primary end-point was 30-day MM. Patients were stratified by preoperative functional status: independent (IND) vs dependent (DEP). Associated patient demographic/clinical data were analyzed using univariate and multivariate methods. Composite odds ratios were constructed with clusters of high-risk comorbidities. RESULTS: There were 5639 BPG patients (4600 [81.6%] IND and 1039 [18.4%]) DEP. DEP patients were significantly older (71.6 +/- 11.8 vs 66.8 +/- 11.8 years; P < .0001), had more chronic obstructive pulmonary disease (COPD) (16.7% vs 11.4%; P < .0001), diabetes (54.2% vs 40.7%; P < .0001), dialysis dependence (16.4% vs 5.6%; P < .0001), and critical limb ischemia (64.6% vs 44.0%; P < .0001). DEP patients had a higher incidence of death (6.1% vs 1.5%; P < .0001) and major complications (30.3% vs 14.2%; P < .0001). DEP was an independent predictor of major complications (odds ratio [OR]: 2.0; 95% confidence interval [CI]: [1.7-2.4]; P < .0001) major systemic complications (2.5 [1.9-3.2]; P < .0001), major operative site complications (1.6 [1.4-1.9]; P < .0001) and death (2.3[1.6-3.4]; P < .0001). The combination of DEP with emergency surgery, Cr > 1.8, or rest pain increased the odds of major complications by five, seven, or 11-fold, respectively. The combination of DEP with hemodialysis, emergency surgery, or age > or = 80 years increased the odds of death by 13, 38, or 87-fold, respectively. CONCLUSION: Preoperative DEP is significantly correlated with all adverse 30-day outcomes in BPG patients. Furthermore, when combined in high-risk composites with specific preoperative clinical variables, DEP is associated with prohibitive MM, thereby identifying patient cohorts that may be unsuitable for BPG.

Two routine blood tests-mean corpuscular volume and aspartate aminotransferase-as predictors of delirium tremens in trauma patients.

BACKGROUND: Delirium tremens (DT) in trauma patients is associated with significant morbidity and mortality. Short interview tools have been used to determine the risk of DT but require an alert, compliant patient and a motivated physician. The mean corpuscular volume (MCV) and aspartate aminotransferase (AST) levels are parts of routine laboratory testing, influenced by excessive alcohol consumption, and may serve as predictors of DT. This study examines the predictive ability of these two readily available biological markers. METHODS: The records of 423 consecutive trauma patients who presented to a Level I trauma center with a positive toxicology screen for alcohol were reviewed. The outcome variable was DT, as defined by the presence of tremor, diaphoresis, autonomic instability, and hallucinations. The positive predictive value (PPV), negative predictive value (NPV), and likelihood ratio (LR) of the admission MCV and AST values were calculated for the prediction of DT. RESULTS: Of the 336 patients who met the criteria for study participation, 110 were diagnosed with DT due to alcohol withdrawal. When the admission MCV and AST were normal, only 3 patients (3.8%) developed DT. The NPV, PPV, and LR with two normal values together were 58.2%, 3.8%, and 0.080, respectively. When both were abnormal, 72 patients (64.3%) developed DT. The NPV, PPV, and LR with two abnormal values together were 83%, 64.3%, and 3.698, respectively. CONCLUSION: Normal admission MCV and AST values in intoxicated trauma patients nearly exclude the development of DT.

The better colectomy project: association of evidence-based best-practice adherence rates to outcomes in colorectal surgery.

OBJECTIVE: To evaluate whether adherence to evidence-based best practices in colorectal surgery predicts improved postoperative outcomes. SUMMARY AND BACKGROUND DATA: Over a quarter of a million colon and rectal resections are performed annually in the United States. The average postoperative complication rate for these procedures approaches 30%. METHODS: A panel of colorectal and general surgeons from 3 hospitals (1 academic medical center and 2 community hospitals) was assembled to ascertain a set of 37 evidence-based practices that they felt were the most pertinent to the evaluation and management of a patient undergoing a colorectal resection. Fifteen of these practices were classified as "key processes" for the prevention of complications. We then retrospectively reviewed medical records for 370 consecutive patients undergoing colorectal resection at these institutions. We evaluated the association of best-practice adherence to complications in the subset of patients with outcome data available through the American College of Surgeons National Surgical Quality Improvement Program. RESULTS: Nonadherence rates exceeded 40% for 11 practices (including 2 key processes: avoidance of unnecessary blood transfusions and timely removal of central venous catheters). Among 198 patients with American College of Surgeons National Surgical Quality Improvement Program outcomes data, 38 (19%) experienced complications, of which 31 (82%) involved postoperative infection. Nonadherence to key-processes significantly predicted the occurrence of a complication (P = 0.002). Each additional process missed increased the odds of a postoperative complication by 60% (odds ratio: 1.6; 95% confidence interval: 1.2­2.2). CONCLUSIONS: Failures of adherence with best practices in colorectal surgery is associated with an increased occurrence of complications. This study merits further research to confirm that improvement in compliance with perioperative best practices will reduce complication rates significantly.