Identifying risk factors for postoperative ileus following open abdominal aortic aneurysm repair.

BACKGROUND: Postoperative ileus (POI) is a common complication following major abdominal surgery. The majority of the data available regarding POI after abdominal surgery is from the gastrointestinal and urological literature. These data have been extrapolated to vascular surgery, especially with regard to enhanced recovery programs for open abdominal aortic aneurysm (AAA) surgery. However, vascular patients are a unique patient population and extrapolation of gastrointestinal and urological data may not necessarily be appropriate. Therefore, the purpose of this study was to delineate the prevalence and risk factors of POI in patients undergoing open AAA surgery. METHODS: This was a retrospective, single-institution study of patients who underwent open AAA surgery from January 2016 to July 2023. Patients were excluded if they had undergone nonelective repairs or had expired within 72 hours of their index operation. The primary outcome was rates of POI, which was defined as the presence of two or more of the following after the third postoperative day: nausea and/or vomiting, inability to tolerate oral food intake, absence of flatus, abdominal distension, or radiological evidence of ileus. RESULTS: A total of 123 patients met study criteria with an overall POI rate of 8.9% (n = 11). Patients who developed a POI had a significantly lower body mass index (24.3 kg/m2 vs 27.1 kg/m2; P = .003), were more likely to undergo a transperitoneal approach (81.8% vs 42.0%; P = .022), midline laparotomy (81.8% vs 37.5%; P = .008), longer total clamp times (151.6 minutes vs 97.7 minutes; P = .018), greater amounts of intraoperative crystalloid infusion (3495 mL vs 2628 mL; P = .029), and were more likely to return to the operating room (27.3% vs 3.6%; P = .016). Proximal clamp site was not associated with POI (P=.463). Patients with POI also had higher rates of postoperative vasopressor use (100% vs 61.1%; P = .014) and greater amounts of oral morphine equivalents in the first 3 postoperative days (488.0 ± 216.0 mg vs 203.8 ± 29.6 mg; P = .016). Patients who developed POI had longer lengths of stay (12.5 days vs 7.6 days; P < .001), a longer duration of nasogastric tube decompression (5.9 days vs 2.2 days; P < .001), and a longer period of time before diet tolerance (9.1 days vs 3.7 days; P < .001). Of those who developed a POI (n = 11), four (36.4%) required total parental nutrition during the admission. CONCLUSIONS: POI is a morbid complication among patients undergoing elective open AAA surgery that prolongs hospital stay significantly. Patients at risk for developing a POI are those with a lower body mass index, as well as those who had an operative repair via a transperitoneal approach, midline laparotomy, longer clamp times, larger amounts of intraoperative crystalloid infusion, a return to the operating room, postoperative vasopressor use, and higher amounts of oral morphine equivalents. These data highlight important perioperative opportunities to decrease the prevalence of POI.

Clinical presentation, outcomes, and threshold for repair by sex in degenerative saccular vs fusiform aneurysms in the descending thoracic aorta.

OBJECTIVE: Saccular-shaped thoracic aortic aneurysms (TAAs) are often treated at smaller diameters compared with fusiform TAAs, despite a lack of strong clinical evidence to support this practice. The aim of this study was to examine differences in presentation, treatment, and outcomes between saccular TAAs and fusiform TAAs in the descending thoracic aorta. We also examined the need for sex-specific treatment thresholds for TAAs. METHODS: All Vascular Quality Initiative (VQI) patients undergoing thoracic endovascular aneurysm repair (TEVAR) for degenerative TAAs in the descending thoracic aorta from 2012 through 2022 were reviewed. Patients were stratified by urgency: emergent/urgent vs elective repairs (ruptured/symptomatic). Demographics, comorbidities, anatomical/procedural characteristics, and outcomes for fusiform TAAs and saccular TAAs were compared. Cumulative distribution curves were used to plot the proportion of patients who underwent emergent/urgent repair according to sex-stratified aortic diameter. RESULTS: Among 655 emergent/urgent TEVARs, 37% were performed for saccular TAAs, whereas among 1352 elective TEVARs, 35% had saccular TAA morphology. Compared with fusiform TAAs, saccular TAAs more frequently underwent emergent/urgent (ruptured/symptomatic) TEVAR below the repair threshold in both females (<50 mm: 38% vs 10%; relative risk, 3.39; 95% confidence interval [CI], 2.04-5.70; P < .001), and males (<55 mm: 47% vs 21%; relative risk, 2.26; 95% CI, 1.60-3.18; P < .001). Moreover, among patients with emergent/urgent fusiform TAAs, females presented at smaller diameters compared with males, whereas there was no difference in preoperative aneurysm diameter among patients with saccular TAAs. Regarding outcomes, emergent/urgent treated saccular TAAs had similar postoperative outcomes and 5-year mortality compared with fusiform TAAs. Nevertheless, in the elective cohort, patients with saccular TAAs had similar postoperative mortality compared with those with fusiform TAAs, but a lower rate of postoperative spinal cord ischemia (0.7% vs 3.2%; P = .010). Furthermore, patients with saccular TAAs had a higher rate of 5-year mortality compared with their fusiform counterparts (23% vs 17%; hazard ratio, 1.53; 95% CI, 1.12-2.10; P = .010). CONCLUSIONS: Patients with saccular TAAs underwent emergent/urgent TEVAR at smaller diameters than those with fusiform TAAs, supporting current clinical practice guideline recommendations that saccular TAAs warrant treatment at smaller diameters. Furthermore, these data support a sex-specific treatment threshold for patients with fusiform TAAs, but not for those with saccular TAAs. Although there were no differences in outcomes following TEVAR between morphologies in the emergent/urgent cohort, patients with saccular TAAs who were treated electively were associated with higher 5-year mortality compared with those with fusiform TAAs.

The effect of supraceliac versus infraceliac landing zone on outcomes following fenestrated endovascular repair of juxta-/pararenal aortic aneurysms.

OBJECTIVE: With increasing experience in fenestrated endovascular aneurysm repair (FEVAR) over time, devices designed to treat juxta-/pararenal aortic aneurysms have evolved in complexity to extend to more proximal landing zones and incorporate more target vessels. We assessed perioperative outcomes in patients who underwent juxta-/pararenal FEVAR with supraceliac vs infraceliac sealing in the Vascular Quality Initiative. METHODS: We identified all patients who underwent elective FEVAR (commercially available FEVAR and physician-modified endografts) for juxta-/pararenal aortic aneurysms in the Vascular Quality Initiative between 2014 and 2021. Supraceliac sealing was defined as proximal sealing in aortic zone 5, or zone 6 with a celiac scallop/fenestration/branch or celiac occlusion. Primary outcomes were perioperative and 3-year mortality. Secondary outcomes included completion endoleaks, in-hospital complications, and factors associated with 3-year mortality. We calculated propensity scores and used inverse probability-weighted Cox regression and logistic regression modeling to assess outcomes. RESULTS: Among 1486 patients identified, 1246 patients (84%) underwent infraceliac sealing, and 240 patients (16%) underwent supraceliac sealing. Of the supraceliac patients, 74 (31%) had a celiac scallop, 144 (60%) had a celiac fenestration/branch, and 22 (9.2%) had a celiac occlusion (intentional or unintentional). After risk-adjusted analyses, there were no differences in perioperative mortality following supraceliac sealing compared with infraceliac sealing (2.3% vs 2.5%; hazard ratio [HR], 0.67; 95% confidence interval [CI], 0.26-1.8; P = .42), or 3-year mortality (12% vs 15%; HR, 0.89; 95% CI, 0.53-1.5; P = .67). Compared with infraceliac sealing, supraceliac sealing was associated with lower odds of type-IA completion endoleaks (odds ratio [OR], 0.24; 95% CI, 0.05-0.67), but higher odds of any complication (12% vs 6.9%; OR, 1.6; 95% CI, 1.01-2.5) including cardiac complications (5.5% vs 1.9%; OR, 2.6; 95% CI, 1.3-5.1), lower extremity ischemia (3.0% vs 0.9%; OR, 3.2; 95% CI, 1.02-9.5), and acute kidney injury (16% vs 11%; OR, 1.6; 95% CI, 1.05-2.3). Though non-significant, there was a trend towards higher risk of spinal cord ischemia following supraceliac sealing compared with infraceliac sealing (1.7% vs 0.8%; OR, 2.2; 95% CI, 0.70-6.4). There were no differences in bowel ischemia between groups (1.7% vs 1.5%; OR, 0.83; 95% CI, 0.24-1.23). A more proximal aneurysm disease extent was associated with higher 3-year mortality (HR zone 8 vs 9, 1.7; 95% CI, 1.1-2.5), whereas procedural characteristics had no influence. CONCLUSIONS: Compared with sealing at an infraceliac level, supraceliac sealing was associated with lower risk of type IA endoleaks and similar mortality. However, clinicians should be aware that supraceliac sealing was associated with higher perioperative morbidity. Future studies with longer follow-up are needed to adequately assess durability differences to comprehensively weigh the risks and benefits of utilizing a higher sealing zone within the visceral aorta for juxta-/pararenal FEVAR.

Statin therapy is associated with improved perioperative outcomes and long-term mortality following carotid revascularization in the Vascular Quality Initiative.

OBJECTIVE: Statin therapy is the standard of care for patients with carotid artery stenosis given its proven cardiovascular benefits. However, the impact of statin therapy on outcomes in patients undergoing carotid revascularization in the Vascular Quality Initiative has not yet been evaluated. Therefore, our aim was to investigate the association of statin therapy with outcomes following carotid endarterectomy (CEA), transfemoral carotid artery stenting (tfCAS), and transcarotid artery revascularization (TCAR). METHODS: We identified all patients who underwent CEA, tfCAS, or TCAR in the Vascular Quality Initiative registry from January 2016 to September 2021. To compare outcomes, we stratified patients by procedure type and created 1:1 propensity score-matched cohorts of patients who received no preoperative statin therapy (within 36 hours of procedure) versus those who received preoperative statin therapy. Propensity scores incorporated demographic characteristics, comorbidities, carotid symptom status, preoperative medications, and physician and hospital procedural experience. The primary outcome was a composite end point of in-hospital stroke and/or death. As a secondary analysis, we performed repeat propensity score-matching by postoperative statin use (prescribed at discharge) and assessed 5-year mortality. Relative risks (RR) and hazard ratios (HR) were calculated using log binomial regression and Cox regression, respectively. RESULTS: Among 97,835 CEA, 20,303 tfCAS, and 22,371 TCAR patients, 15%, 17%, and 10% of patients did not receive preoperative statin therapy, respectively. Compared with statin use, no statin use was associated with a higher risk of in-hospital stroke or death among 13,434 matched CEA patients (no statin, 1.7% vs statin, 1.4%; RR, 1.2; 95% confidence interval [CI], 1.02-1.5) and among 2707 matched tfCAS patients (4.8% vs 2.8%; RR, 1.7; 95% CI, 1.3-2.3). However, there was no difference for this outcome by statin use among 2089 matched TCAR patients (1.8% vs 1.6%; RR, 1.1; 95% CI, 0.7-1.8). At 5 years, no statin therapy at discharge was associated with higher 5-year mortality after CEA (15% vs 10%; HR, 1.8; 95% CI, 1.6-2) and tfCAS (18% vs 14%; HR, 1.5; 95% CI, 1.2-1.8), but there was no difference after TCAR (14% vs 11%; HR, 1.3; 95% CI, 0.9-1.8). CONCLUSIONS: Compared with statin use, no statin use was associated with a higher risk of in-hospital stroke or death and 5-year mortality among CEA and tfCAS patients. Although there was no significant difference in outcomes among TCAR patients, this may in part be due to lower statistical power in this cohort. Overall, statin therapy is essential in the short- and long-term management of patients undergoing carotid revascularization. Our findings not only support current Society for Vascular Surgery recommendations for statin therapy in patients undergoing carotid revascularization, but they also highlight an important opportunity for quality improvement.

Outcomes Following in Situ Reconstruction for Aortic Infection with the Neo-Aortoiliac System and Aortic Homograft.

BACKGROUND: In situ reconstruction is one of the primary surgical options for primary aortic and graft and endograft infections. One institution's outcomes following aortic reconstruction with femoro-popliteal vein (i.e., the neo-aortoiliac system) and cryopreserved aortic allografts are described. METHODS: A retrospective review was performed of any patient who underwent aortic reconstruction with femoropopliteal vein or cryopreserved aortic allograft from 2013-2022 at a single tertiary-care institution. RESULTS: Twenty four patients underwent in situ reconstruction with the neo-aortoiliac system or with cadaveric allograft for primary or secondary aortic infection from 2013-2022. Short-term (30-day) mortality remains low (3/24 or 12.5%) despite the high incidence of major postoperative complications that necessitated reintervention in 11/24 or 45.8% of the cohort, most often for recurrent intracavitary infection. Gram-negative and drug-resistant pathogens were the most commonly implicated organisms in recurrent intra-abdominal infection. Management of early allograft degeneration is also described with extra-anatomic bypass grafting, conduit/graft embolization, which is then followed by allograft explantation and wide surgical debridement. Despite low short-term (30-day) mortality, all-cause 1-year mortality remains elevated at 38.1% (8/21) in those with an adequate follow-up interval. CONCLUSIONS: In situ reconstruction for primary or secondary aortic infections results in excellent short-term patient outcomes but is characterized by a high incidence of reintervention and an elevated all-cause 1-year mortality.

Racial and ethnic disparities in 3-year outcomes following infrainguinal bypass for chronic limb-threatening ischemia.

OBJECTIVE: Black and Hispanic patients have had higher rates of chronic limb-threatening ischemia (CLTI) and experienced worse perioperative outcomes after lower extremity bypass compared with White patients. The underlying reasons for these disparities have remained unclear, and data on 3-year outcomes are limited. Therefore, we examined the differences in 3-year outcomes after open infrainguinal bypass for CLTI stratified by race/ethnicity and explored the potential factors contributing to these differences. METHODS: We identified all CLTI patients who had undergone primary open infrainguinal bypass in the Vascular Quality Initiative registry from 2003 to 2017 with linkage to Medicare claims through 2018 for the 3-year outcomes. Our primary outcomes were the 3-year rates of major amputation, reintervention, and mortality. We also recorded the 30-day major adverse limb events (MALE) defined as major amputation or reintervention. We used Kaplan-Meier estimation methods and multivariable Cox regression analyses to evaluate the outcomes stratified by race/ethnicity and identify contributing factors. RESULTS: Of the 7108 patients with CLTI, 5599 (79%) were non-Hispanic White, 1053 (15%) were Black, 48 (1%) were Asian, and 408 (6%) were Hispanic patients. Compared with White patients, Black patients had higher rates of 3-year major amputation (Black vs White, 32% vs 19%; hazard ratio [HR], 1.9; 95% confidence interval [CI], 1.7-2.2), reintervention (Black vs White, 61% vs 57%; HR, 1.2; 95% CI, 1.1-1.3), and 30-day MALE (Black vs White, 8.1% vs 4.9%; HR, 1.3; 95% CI, 1.2-1.4) but lower mortality (Black vs White, 38% vs 42%; HR, 0.9; 95% CI, 0.8-0.99). Hispanic patients also experienced higher rates of amputation (Hispanic vs White, 27% vs 19%; HR, 1.6; 95% CI, 1.3-2.0), reintervention (Hispanic vs White, 70% vs 57%; HR, 1.4; 95% CI, 1.2-1.6), and MALE (Hispanic vs White, 8.7% vs 4.9%; HR, 1.5; 95% CI, 1.3-1.7. However, mortality was similar between the two groups (Hispanic vs White, 38% vs 42%; HR, 0.88; 95% CI, 0.76-1.0). The low number of Asian patients prevented a meaningful assessment of amputation (Asian vs White, 20% vs 19%; HR, 0.93; 95% CI, 0.44-2.0), reintervention (Asian vs White, 55% vs 57%; HR, 0.79; 95% CI, 0.51-1.2), MALE (Asian vs White, 8.5% vs 4.9%; HR, 0.71; 95% CI, 0.46-1.1), or mortality (Asian vs White, 36% vs 42%; HR, 0.83; 95% CI, 0.52-1.3). In the adjusted analyses, the association of Black race and Hispanic ethnicity with amputation and reintervention was explained by differences in the demographic characteristics (ie, age, sex) and baseline comorbidities (ie, tobacco use, diabetes, renal disease). CONCLUSIONS: Compared with White patients, Black and Hispanic patients had higher 3-year major amputation and reintervention rates. However, mortality was lower for Black patients than for the White patients and similar between Hispanic and White patients. Disparities in amputation and reintervention were partly attributable to differences in demographic characteristics and the higher prevalence of comorbidities in Black and Hispanic patients with CLTI. Future work is necessary to determine whether interventions to improve access to care and reduce the burden of comorbidities in these populations will confer limb salvage benefits.

Underutilization of Guideline-based Abdominal Aortic Aneurysm Screening in an Academic Health System.

OBJECTIVES: The US Preventive Services Task Force (USPSTF) recommends a 1 time screening for AAA with ultrasonography in men aged 65-75 who have ever smoked. Our objectives were to identify the AAA screening rates in a large academic health system and assess factors associated with receipt of screening. METHODS: Data were extracted from electronic health records from the Duke University Health System and the US Census Bureau. Index screening eligibility date was defined as the 65th birthdate for male patients with a history of smoking. Patients with an index screening eligibility date between January 1, 2016 and December 31, 2018 were included in the study population and followed through December 31, 2019. Screened patients were identified by procedure codes for ultrasonography, CT or MRI. RESULTS: Among 6,682 eligible patients who turned 65 years old between January 1, 2016 and December 31, 2018 with at least 1 year of follow-up, only 463 (6.9%) received AAA screening during the study period. The odds of receiving AAA screening within 1 year of index eligibility were 27% lower for Black patients compared to whites [OR = 0.73, 95% CI (0.58,0.93)]. Patients who visited a PCP or were diagnosed with hypertension had 75% and 41% greater odds of receiving screening, respectively [OR 1.75, 95% CI (1.36,2.25)] and [OR 1.41 95% CI (1.11,1.80)] compared with patients who did not. Among 4,580 men with 2 years of follow-up, AAA screening rate increased to 13.0%. Patients who visited a PCP had 64% greater odds of receiving screening within 2 years of index eligibility compared to those who did not [OR = 1.64, 95% CI (1.30,2.06)]. CONCLUSIONS: Screening for AAA per USPSTF guidelines is underutilized with evidence of a racial disparity. Although PCP visit is the most consistent predictor of screening, provider screening rates are low.