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. 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.

Predicting the future caretakers of traumatic vascular injury management via operative exposure among surgical trainees.

BACKGROUND: The management of vascular trauma requires specialized training and expertise. Although traumatic vascular injury is treated currently by both vascular and trauma surgeons in modern practice, it remains unclear who will inherit the role of managing vascular trauma in the coming decades. In this study, we examined disparities in operative experience in vascular trauma among surgical trainees across different surgical specialties. METHODS: Accreditation Council for Graduate Medical Education national operative log reports were collected for graduating vascular surgery residents (VSRs), vascular surgery fellows (VSFs), and general surgery residents (GSRs) from 2012 to 2022. Total operative volume for traumatic vascular injury was examined, as were the five major contributing operative domains (neck, thoracic, abdominal, peripheral, and fasciotomy). RESULTS: A total of 22,052 GSRs, 334 VSRs, and 1672 VSFs graduated over the 10-year study period. VSR had the highest vascular trauma case volume (24.9 ± 3.9 cases/5 years), followed by VSF (22.1 ± 1.5 cases/2 years) then GSR (2.4 ± 0.3 cases/5 years; P < .001). Thoracic vessel exploration/repair (0.7 cases vs 0.6 cases vs 0.0 cases), abdominal vessel exploration/repair (1.0 cases vs 0.9 cases vs 0.0 cases), neck vessel exploration/repair (4.0 cases vs 3.4 cases vs 0.2 cases), peripheral vessel exploration/repair (12.1 cases vs 9.5 cases vs 1.1 cases), and lower extremity fasciotomy for trauma (7.2 cases vs 7.6 cases vs 1.1 cases) were most frequent among the VSR and VSF groups (P < .001 each). On linear regression analysis, both VSF (+0.5 cases/y; R2 = 0.81; P < .001) and GSR (+0.1 cases/y; R2 = 0.75; P = .001) groups experienced a growth in vascular trauma volume. Contrariwise, vascular trauma volume did not change among graduating VSRs (R2 = 0.13; P = .31). CONCLUSIONS: Dedicated vascular surgical training provides the highest operative exposure to civilian vascular trauma in the United States.

Pilot Study to Improve Resident Experience on Vascular Surgery by Standardizing Dissemination of Operative Steps.

OBJECTIVE: Many surgical residencies have passed along attendings preferences and procedural knowledge as a highly utilized but informal resource. The objective was to assess the effect of providing operative steps and attending preferences on surgical resident performance. DESIGN: This was a prospective observational study with a survey-based design. SETTING: We created and shared vascular surgery operative steps including institutional and attending preferences with junior residents at the Massachusetts General Hospital. PARTICIPANTS: There were a total of 31 residents who completed a survey to assess self-perception of performance in operative knowledge and Accreditation Council for Graduate Medical Education (ACGME) Milestone criteria. RESULTS: Advice from colleagues was the most utilized resource, followed by web-based materials. Of the web-based materials, almost all residents utilized Google searches over other web-based resources designed to specifically help surgical trainees. The vascular surgery resource was used by 90% of residents more than 3 times per week to prepare for operative cases. There was significant improvement in patient positioning, instrument selection, operative field exposure, anatomy, sequence of procedure, procedure choices, and peri-operative care knowledge. CONCLUSIONS: Development of institutional resources that specifically capture attending surgeon procedural variations can improve resident performance, encourage resident autonomy, and provide a catalog of approaches to challenging operative situations.

Effect of EVAR on International Ruptured AAA Mortality-Sex and Geographic Disparities.

Background: We sought to investigate the differential impact of EVAR (endovascular aneurysm repair) vis-à-vis OSR (open surgical repair) on ruptured AAA (abdominal aortic aneurysm) mortality by sex and geographically. Methods: We performed a retrospective study of administrative data on EVAR from state statistical agencies, vascular registries, and academic publications, as well as ruptured AAA mortality rates from the World Health Organization for 14 14 states across Australasia, East Asia, Europe, and North America. Results: Between 2011-2016, the proportion of treatment of ruptured AAAs by EVAR increased from 26.1 to 43.8 percent among females, and from 25.7 to 41.2 percent among males, and age-adjusted ruptured AAA mortality rates fell from 12.62 to 9.50 per million among females, and from 34.14 to 26.54 per million among males. The association of EVAR with reduced mortality was more than three times larger (2.2 vis-à-vis 0.6 percent of prevalence per 10 percentage point increase in EVAR) among females than males. The association of EVAR with reduced mortality was substantially larger (1.7 vis-à-vis 1.1 percent of prevalence per 10 percentage point increase in EVAR) among East Asian states than European+ states. Conclusions: The increasing adoption of EVAR coincided with a decrease in ruptured AAA mortality. The relationship between EVAR and mortality was more pronounced among females than males, and in East Asian than European+ states. Sex and ethnic heterogeneity should be further investigated.

Assessment of fitness for open repair in patients with infrarenal abdominal aortic aneurysms.

OBJECTIVE: Endovascular aortic repair (EVAR) was originally designed as a treatment modality for patients with abdominal aortic aneurysms (AAAs) deemed unfit for open repair. However, the definition of "unfit for open repair" is largely subjective and heterogenous. The purpose of this study was to compare patients deemed unfit for open repair who underwent EVAR to a matched cohort who underwent open repair for infrarenal AAAs. METHODS: The Vascular Quality Initiative of the Society for Vascular Surgery was queried for patients who underwent EVAR and open infrarenal AAA repair from 2003 to 2022. Patients that underwent EVAR were included if they were deemed unfit for open repair by the operating surgeon. EVAR patients deemed unfit because of a hostile abdomen were excluded. Patients in both the open and EVAR datasets were excluded if their repair was deemed non-elective or if they had prior aortic surgery. EVAR patients were matched to a cohort of open patients. The primary outcome for this study was 1-year mortality. Secondary outcomes included 30-day mortality, major adverse cardiac events, pulmonary complications, non-home discharge, reinterventions, and 5-year survival. RESULTS: A total of 5310 EVAR patients were identified who were deemed unfit for open repair. Of those, 3028 EVAR patients (57.0%) were able to be matched 1:1 to a cohort of open patients. Open patients had higher rates of major adverse cardiac events (20.2% vs 4.4%; P < .001), pulmonary complications (12.8% vs 1.6%; P < .001), non-home discharges (28.5% vs 7.9%; P < .001), and 30-day mortality (4.5% vs 1.4%; P < .001). There were no differences in early survival, but open repair had better middle and late survival compared with EVAR over the course of 5 years. A total of 74 EVAR patients (2.4%) had reinterventions during the study period. EVAR patients that required interventions had higher 1-year (40.5% vs 7.3%; P < .001) and 5-year mortality (43.2% vs 14.1%; P < .001) compared with those that did not require reinterventions. EVAR patients who had reinterventions had higher 1-year (40.5% vs 6.3%; P < .001) and 5-year (43.2% vs 20.3%; P = .006) mortality compared with their matched open cohort. CONCLUSIONS: Patients undergoing EVAR for AAAs who are deemed unfit for open repair have better perioperative morbidity and mortality compared with open repair. However, patients who had an open repair had better middle and late survival over the course of 5 years. The categorization of unfitness for open surgery may be inaccurate and re-evaluation of this terminology/concept should be undertaken.

Room for improvement in patient compliance during peripheral vascular interventions.

Introduction: For patients receiving Procedural Sedation and Analgesia (PSA), patient cooperation is crucial as patients remain continuously aware of operating room activity and can be asked to perform tasks such as prolonged breath-holds. This survey aimed to collect information on patient compliance with on-table instructions and its relation to periprocedural outcomes from surgeons nationwide performing peripheral vascular interventions (PVI) under PSA. Methods: A 9-question online survey was sent to 383 vascular surgeons (including both vascular surgery attendings and trainees) across the United States through REDCap from August 30 to September 21, 2021, with responses closed on October 30, 2021. The survey response was analyzed with descriptive statistics. Results: 83 (21.6%) vascular surgeons responded to the survey, of which 67 (80.7%) were attending vascular surgeons and 16 (19.3%) were vascular surgery trainees. 41 (49.4%) respondents performed 11-20 PVI cases under PSA every month, while 31 (41.0%) respondents performed 1-10 PVI cases under PSA every month. 41 (49.4%) respondents reported that in 1-10% of their cases, additional contrast and/or radiation was administered because patient moved on the table or did not cooperate with breath holds; 25 (30.1%) reported that this occurred in 11-20% of their cases, 12 (14.5%) reported that this occurred in 21-50% of their cases and 4 (4.8%) reported that this occurred in over 50% of their cases. In such cases, the majority of respondents reported a 1-10% increase in contrast volume (59.0%), radiation dosage (62.7%), sedative/analgesia administration (46.3%) and procedural time (54.9%). Of cases being converted to general anesthesia due to inadequate patient cooperation, 35 (42.2%) respondents reported between 1-5 per month, and 3 (3.6%) respondents reported between 6-10 per month. Of cases being aborted due to inadequate patient cooperation, 25 (30.1%) respondents reported between 1-5 per month, and 1 (1.2%) respondents reported between 6-10 per month. Conclusion: A significant fraction of PVI cases performed under PSA result in increased radiation and contrast exposure, sedative administration and procedural time due to inadequate patient cooperation. In certain cases, conversion to general anesthesia or case abortion is required. Further research should be performed to investigate strategies to minimize such adverse patient safety events.

Increased anti-thrombotic therapy is associated with decreased major adverse limb events in patients with low wound and foot infection scores.

INTRODUCTION: The optimal anti-thrombotic management of patients after lower extremity bypass has yet to be fully elucidated, in part due to significant heterogeneity in patient presentation and practice patterns. The Wound, Ischemia, and foot Infection (WIfI) score is a validated scoring system to assist in the management of patients with chronic limb threatening ischemia (CLTI). We hypothesized that performing a restriction analysis based on WIFI scores would assist in the postoperative anti-thrombotic management of patients undergoing infrainguinal bypass. METHODS: A retrospective cohort of infrainguinal bypass procedures completed at a single hospital system between January 2018 and January 2021 was selected, and preoperative WIfI scores were extracted for each patient. Patients with either Wound scores of 2 and 3, or Ischemia Scores of 0 and 1, or Foot Infection Scores of 3 were excluded. Based on the type of anti-thrombotic regimen on discharge, demographics, comorbidities, type of bypass, 30-day rates of graft occlusion, major amputation, mortality, and major adverse limb events (MALE) were analyzed. Statistical analysis included t-tests, chi square tests, and time-to-event survival analysis. RESULTS: 230 procedures were included in the study. 69 (30.0%) patients were discharged on single antiplatelet therapy (SAPT), compared to 161 (70.0%) who were discharged on either dual antiplatelet therapy or anticoagulation (DAPT/AC). There was a higher prevalence of bypasses using prosthetic conduit in the DAPT/AC group (45.9 vs 31.8%, p = .047); no other demographic or procedural variable analyzed had any significant differences. At 30-days postoperatively, there was no significant difference in postoperative reintervention rates, however, the DAPT/AC group had significantly lower rates of mortality (1.2 vs 7.2%, p = .01), major amputation (1.2% vs 5.8%, p = .04), and MALE (3.7 vs 13.0%, p < .01). There were no significant differences in bleeding complications. Survival analysis demonstrated that MALE-free survival was higher in the DAPT/AC group compared to the SAPT group (p < .01). On Cox regression analysis, DAPT/AC was associated with significantly decreased rates of MALE + mortality (Hazard Ratio (HR) 0.20 [0.06 - 0.66]). CONCLUSION: Lower extremity bypasses patients with low Wound and low foot Infection scores who are discharged on DAPT/AC postoperatively have a significantly higher 30-day MALE-free survival rate compared to patients discharged on SAPT; consideration could be made to preferentially discharge such post-bypass patients on DAPT/AC.

Implementation of a Consensus-Driven Quality Improvement Protocol to Decrease Length of Stay after Elective Carotid Endarterectomy.

BACKGROUND: National guidelines stipulate that postoperative length-of-stay (LOS) after elective carotid endarterectomy (CEA) should not exceed 1 day on average, yet perioperative care coordination gaps may limit the ability for institutions to achieve this goal. Internal review determined that increased LOS after CEA at our institution was frequently attributable to urinary retention or postoperative hypertension. We designed and implemented a quality improvement (QI) protocol aiming to better our institutional performance in postoperative LOS after CEA, consisting of 2 Plan-Do-Study-Act (PDSA) cycles. METHODS: In the first PDSA cycle, a division-wide standardized protocol was developed by which antihypertensive medications were managed preoperatively and through postoperative day (POD) 1. This protocol included dedicated patient outreach with instructions for at-home antihypertensive management through the morning of POD 0. Second, alpha-1-blockade was administered to all male patients preoperatively. All patients receiving an elective CEA performed at our institution by vascular surgeons were included in the protocol. The primary outcome measure was defined percent failure of the LOS >1 day metric, with raw LOS as a secondary outcome measure. Process measures included adherence to the antihypertensive medication protocol and adherence to preoperative alpha-1 blockade. Balance measures included documented intraoperative hypotension and 30-day readmission. Fisher's exact test was used to evaluate relationships between preintervention and postintervention cohorts and the outcome measure. Wilcoxon rank-sum tests were used to evaluate relationships between cohorts and total LOS. RESULTS: Baseline performance on the LOS >1 day metric after elective CEA was 58.3% in the 8 months prior to intervention, across 48 patients. Both PDSA interventions were implemented simultaneously. In the 12 months after intervention, 64 patients met protocol inclusion criteria, including 19 symptomatic patients (29.7%). Process measure success for preoperative antihypertensive regimen adherence was 89.8%. For males not chronically prescribed alpha-1 blockade preoperatively, process measure success for adherence to preoperative alpha-1 blockade was 78.8%. The intraoperative hypotension balance measure occurred in 1 patient (1.6%). Performance on the LOS >1 day outcome measure was improved to 32.8% (P = 0.01). Performance on the raw LOS outcome measure was similar between the preintervention cohort (median 2 days, interquartile range [IQR] 1-2) and postintervention cohort (median 1 day, IQR 1-2, P = 0.07). Performance on the 30-day readmission balance measure was similar between preintervention (6.3%) and postintervention cohorts (9.4%, P = 0.73). CONCLUSIONS: The consensus-driven development and implementation of a QI protocol to reduce postoperative LOS after CEA showed promising results in our institution, with approximately 40% improvement in the primary outcome measure. Wider efforts to improve LOS after CEA should include a focus on minimization of postoperative hypertension and urinary retention.

Greater Patient Travel Distance is Associated with Perioperative and One-Year Cost Increases After Complex Aortic Surgery.

BACKGROUND: With increasing regionalization of complex aortic surgery within fewer US centers, patients may face increased travel burden when accessing aortic surgery. Longer travel distances have been associated with inferior outcomes after major surgery; however, the impacts of distance on reinterventions and costs have not been described. This study aims to assess the association between patient travel distance and longer-term outcomes including costs and reinterventions after complex aortic surgery. METHODS: A retrospective review was conducted of all patients in the Vascular Implant Surveillance and Interventional Outcomes Network database undergoing complex endovascular aortic repair including internal iliac or visceral vessel involvement, complex thoracic endovascular aortic repair including Zone 0-2 proximal extent or branched devices, and complex open abdominal aortic aneurysm repair including suprarenal or higher clamp sites. Travel distance was stratified by Rural-Urban Commuting Area population-density category. Multinomial logistic regression models, negative-binomial models, and zero-inflated Poisson models were used to assess the association between travel distance and index procedural and comprehensive first-year costs, long-term imaging, and long-term reinterventions, respectively. RESULTS: Between 2011 and 2018, 8,782 patients underwent complex aortic surgery in the Vascular Implant Surveillance and Interventional Outcomes Network database, including 4,822 complex endovascular aortic repairs, 2,672 complex thoracic endovascular aortic repairs, and 1,288 complex open abdominal aortic aneurysm repairs. Median travel distance was 22.8 miles (interquartile range 8.6-54.8 miles, range 0-2,688.9 miles). Median age was 75 years for all distance quintiles. Patients traveling farther were more likely to be female (26.8% in quintile 5 [Q5] vs. 19.9% in Q1, P < 0.001) and to have had a prior aortic surgery (20.8% for Q5 vs. 5.9% for Q1, P < 0.001). Patients traveling farther had higher index procedural costs, with adjusted odds ratio (OR) 2.34 (95% confidence interval [CI] 1.86-2.94, P < 0.0001) of being in the highest cost tertile versus lowest for patients in Q5 vs. Q1. For patients with ≥ 1-year follow-up, those traveling farther had higher imaging costs, with adjusted Q5 OR 1.55 (95% CI 1.22-1.95, P = 0.0002), and comprehensive first-year costs, with adjusted Q5 OR 2.06 (95% CI 1.57-2.70, P < 0.0001). In contrast, patients traveling farther had similar numbers of reinterventions and imaging studies postoperatively. CONCLUSIONS: Patients traveling farther for complex aortic surgery have higher procedural costs, postoperative imaging costs, and comprehensive first-year costs. These patients should be targeted for increased care coordination for improved outcomes and healthcare system burden.

Inferior mesenteric artery revascularization can supplement salvage of mesenteric ischemia.

The inferior mesenteric artery (IMA) has often been overlooked in favor of the celiac or superior mesenteric artery in arterial mesenteric ischemia, owing to the typically robust visceral collateral networks. In the present report, we have described a case series of patients in whom "salvage" revascularization of the IMA was performed after attempted celiac or superior mesenteric artery revascularization had been unsuccessful. The restored IMA inflow had resolved the symptoms for three patients. However, sole IMA revascularization was insufficient to reverse the course for two other patients with severe acute-on-chronic mesenteric ischemia. The IMA should be considered for salvage revascularization in the appropriate clinical scenario.

Routine Completion Angiography for Infrainguinal Bypasses Using Prosthetic Conduit: No Effect on Postoperative Patency.

BACKGROUND: Recent studies have demonstrated increased postoperative patency with the use of routine completion angiography for bypass using venous conduit. Compared to vein conduits, however, prosthetic conduits are less plagued by technical issues such as unlysed valves or arteriovenous fistulae. The effect of routine completion angiography on bypass patency in prosthetic bypasses has yet to be compared to the more traditional selective use of completion imaging. METHODS: A retrospective review of all infrainguinal bypass procedures using prosthetic conduit completed at a single hospital system from 2001 to 2018 was performed. Demographics, comorbidities, intraoperative reintervention rates, and 30-day rates of graft thrombosis were analyzed. Statistical analysis included t-tests, chi-square tests, and cox regression. RESULTS: Four hundred and ninety-eight bypasses that were performed in 426 patients met inclusion criteria. Fifty-six (11.2%) bypasses were classified into the routine completion angiogram group compared to 442 (88.8%) into the no completion angiogram group. Patients who underwent routine completion angiograms had a rate of intraoperative reintervention of 21.4%. When comparing bypasses that underwent routine completion angiography versus no completion angiography, there were no significant differences in rates of reintervention (3.5% vs. 4.5%, P = 0.74) or graft occlusion (3.5% vs. 4.7%, P = 0.69) at 30-days postoperatively. CONCLUSIONS: Almost one-quarter of lower extremity bypasses using prosthetic conduit that undergo routine completion angiography undergo postangiogram bypass revision; however, this is not associated with an increased graft patency at 30 days postoperatively.

Longer patient travel distance is associated with increased non-index readmission after complex aortic surgery.

OBJECTIVE: Recently evolving practice patterns in complex aortic surgery have led to regionalization of care within fewer centers in the United States, and thus patients may have to travel farther for complex aortic care. Travel distance has been associated with inferior outcomes after non-vascular surgery, particularly non-index readmission. This study aims to assess the impact of patient travel distance on perioperative outcomes and readmissions after complex aortic surgery. METHODS: A retrospective review was conducted of all patients in the Vascular Quality Initiative and Vascular Implant Surveillance and Interventional Outcomes Network databases undergoing complex endovascular aortic repair (EVAR) including internal iliac or visceral vessel involvement, complex thoracic endovascular aortic repair (TEVAR) including zone 0 to 2 proximal extent or branched devices, and complex open abdominal aortic aneurysm (AAA) repair including suprarenal or higher clamp sites. Travel distance was stratified by rural/urban commuting area (RUCA) population-density category. Wilcoxon and χ2 tests were used to assess relationships between travel distance quintiles and baseline characteristics, mortality, and readmission. Travel distance and other factors were included in multivariable Cox models for survival and Fine-Gray competing risk models for freedom from readmission. RESULTS: Between 2011 and 2018, 8782 patients underwent complex aortic surgery in the Vascular Quality Initiative and Vascular Implant Surveillance and Interventional Outcomes Network databases, including 4822 complex EVARs, 2672 complex TEVARs, and 1288 complex open AAA repairs. Median travel distance was 22.8 miles (interquartile range [IQR], 8.6-54.8 miles). Median age was 75 years for all distance quintiles, but patients traveling longer distances were more likely female (26.8% in quintile 5 [Q5] vs 19.9% in Q1; P < .001), white (93.8% of Q5 vs 83.8% of Q1; P < .001), to have larger-diameter AAAs (median 59 mm for Q5 vs 55 mm for Q1; P < .001), and to have had prior aortic surgery (20.8% for Q5 vs 5.9% for Q1; P < .001). Overall 30-day readmission was more common at farther distances (18.1% for Q5 vs 14.8% for Q1; P = .003), with higher non-index readmission (11.2% for Q5 vs 2.7% for Q1; P < .001) and conversely lower index readmission (6.9% for Q5 vs 12.0% for Q1; P < .001). Multivariable-adjusted Fine-Gray models confirmed greater hazard of non-index readmission with farther distance, with a Q5 hazard ratio of 3.02 (95% confidence interval, 2.12-4.30; P < .001). Multivariable-adjusted Cox models demonstrated no association between travel distance and long-term survival but found that non-index readmission was associated with increased long-term mortality (hazard ratio, 1.46; 95% confidence interval, 1.20-1.78; P = .0001). CONCLUSIONS: Patients traveling farther for complex aortic surgery demonstrate higher non-index readmission, which, in turn, is associated with increased long-term mortality risk. Aortic centers of excellence should consider targeting these patients for more comprehensive follow-up and care coordination to improve outcomes.

Partial and complete explantation of aortic endografts in the modern era.

OBJECTIVE: Despite the progressive advancement of devices for endovascular aortic repair (EVAR), endografts continue to fail, requiring explant. We present a single-institutional experience of EVAR explants, characterizing modern failure modes, presentation, and outcomes for partial and complete EVAR explantation. METHODS: A retrospective analysis was performed of all EVARs explanted at an urban quaternary center from 2001 to 2020, with one infected endograft excluded. Patient and graft characteristics, indications, and perioperative and long-term outcomes were analyzed. Partial versus complete explants were performed per surgeon discretion without a predefined protocol. This process was informed by patient risk factors; asymptomatic, symptomatic, or ruptured aneurysm presentation; and anatomical or intraoperative factors, including endoleak type. RESULTS: From 2001 to 2020, 52 explants met the inclusion and exclusion criteria. More than one-half (57.7%) were explants of EVAR devices placed at outside institutions, designated nonindex explants. Most patients were male (86.5%), the median age was 74 years (interquartile range, 70-78 years). More than one-half (61.5%) were performed in the second decade of the study period. The most commonly explanted grafts were Gore Excluder (n = 9 grafts), Cook Zenith (n = 8), Endologix AFX (n = 7), Medtronic Endurant (n = 5), and Medtronic Talent (n = 5). Most grafts (78.8%) were explanted for neck degeneration or sac expansion. Five were explanted for initial seal failure, five for symptomatic expansion, and seven for rupture. The median implant duration was 4.2 years, although ranging widely (interquartile range, 2.6-5.1 years), but similar between index and nonindex explants (4.2 years vs 4.1 years). Partial explantation was performed in 61.5%, with implant duration slightly lower, 3.2 years versus 4.4 years for complete explants. Partial explantation was more frequent in index explants (68.2% vs 56.7%). The median length of stay was 8 days. The median intensive care unit length of stay was 3 days, without significant differences in nonindex explants (4 days vs 3 days) and partial explants (4 days vs 3 days). Thirty-day mortality occurred in two nonindex explants (one partial and one complete explant). Thirty-day readmission was similar between partial and complete explants (9.7% vs 5.0%), without accounting for nonindex readmissions. Long-term survival was comparable between partial and complete explants in Cox regression (hazard ratio, 2.45; 95% confidence interval, 0.79-7.56; P = .12). CONCLUSIONS: Explants of EVAR devices have increased over time at our institution. Partial explant was performed in more than one-half of cases, per operating surgeon discretion, demonstrating higher blood loss, more frequent acute kidney injury, and longer intensive care unit stays, however with comparable short-term mortality and long-term survival.

Reassuring Intraoperative Parameters Do Not Obviate the Need for Infrainguinal Bypass Completion Angiograms.

OBJECTIVE: To determine if routine completion angiography for lower extremity bypasses using vein conduit results in lower rates of postoperative bypass occlusion. SUMMARY OF BACKGROUND DATA: With the increasing availability of on-table angiography and significant advancements in endovascular techniques, some operators routinely perform completion angiograms. The effect of this surgical paradigm has yet to be rigorously compared to the more widespread selective use of completion imaging in the modern era. METHODS: This retrospective cohort study included infrainguinal arterial bypass procedures utilizing vein conduit completed at a single hospital system from 2001 to 2018 and compared postoperative outcomes between bypasses that underwent routine completion angiography versus selective completion angiography. Notably, any bypasses that underwent completion angiography due to intraoperative concerns were excluded from this analysis. RESULTS: 666 bypasses that were performed in 589 patients met inclusion criteria. 126 (16.9%) bypasses were classified into the routine completion angiogram group compared to 540 (81.0%) into the selective completion angiogram group. Patients who underwent routine completion angiograms had a rate of intraoperative reintervention of 22.2%. The routine angiogram group had lower rates of reintervention (3.9% vs 10.0%, P = 0.03) and graft occlusion (2.3% vs 9.2%, P = 0.01) at 1-month postoperatively. CONCLUSION: Lower extremity bypasses using vein conduit that undergo routine completion angiography are associated with lower rates of graft occlusion at 30-days postoperatively. Completion angiography should thus be routinely performed in infrainguinal bypasses that utilize venous conduit.

Trends in Female Authorship in High Impact Surgical Journals Between 2008 and 2018.

OBJECTIVE: This study evaluates the distribution of authorship by sex over the last 10 years among the top 25 surgical journals. SUMMARY OF BACKGROUND DATA: Despite an increase in women entering surgical residency, there remains a sex disparity in surgical leadership. Scholarly activity is the foundation for academic promotion. However, few studies have evaluated productivity by sex in surgical literature. METHODS: Original research in the 25 highest-impact general surgery/subspecialty journals were included (1/2008-5/2018). Journals with <70% identified author sex were excluded. Articles were categorized by sex of first, last, and overall authorship. We examined changes in proportions of female first, last, and overall authorship over time, and analyzed the correlation between these measurements and journal impact factor. RESULTS: There were 71,867 articles from 19 journals included. Sex was successfully predicted for 87.3% of authors (79.1%-92.5%). There were significant increases in the overall percentage of female authors (ß = 0.55, P < 0.001), female first authors (ß = 0.97, P < 0.001), and female last authors (ß = 0.53, P < 0.001) over the study period. Notably, all cardiothoracic subspecialty journals did not significantly increase the proportion of female last authors over the study period. There were no correlations between journal impact factor and percentage of overall female authors (rs = 0.39, P = 0.09), female first authors (rs = 0.29, P = 0.22), or female last author (rs = 0.35, P = 0.13). CONCLUSIONS: This study identifies continued but slow improvement in female authorship of high-impact surgical journals during the contemporary era. However, the improvement was more apparent in the first compared to senior author positions.

Outcomes of open and endovascular repair of Kommerell diverticulum.

OBJECTIVES: Kommerell diverticulum (KD) is a rare congenital vascular anomaly often associated with an aberrant subclavian artery (ASCA). Definitive indications for intervention remain unclear. We present open and endovascular (EV) operative outcomes in a large contemporary series and propose a management algorithm. METHODS: Between 2004 and 2020, 224 patients presented with ASCA and associated KD to our institution. Of the 43 (19.2%) patients who underwent operative repair, 31 (72.1%) had open surgical (OS) repair via thoracotomy and 12 (27.9%) had EV repair. Univariable and bivariable statistical analyses were conducted stratified by approach. The median follow-up time was 5.4 years (IQR, 2.9-9.7). RESULTS: Patients in EV group were older (68 years vs 47 years, P < 0.001) and had larger aneurysms (base diameter 3.2 cm vs 21.5 cm, P = 0.007). All patients with dysphagia lusoria were treated with open surgery (n = 20). Asymptomatic patients with incidentally detected KD (50% vs 16.1%), those with chest or back pain (50% vs 19.4%) and patients who presented with an aortic emergency (25% vs 6.5%) were more likely to be treated endovascularly (P = 0.001). Carotid-to-subclavian bypass was used in 38 (88.4%) patients. There were no operative mortalities. In-hospital mortality was similar between groups (3.2% vs 16.7%, P = 0.121). Mid-term mortality was higher in the EV group [4 (33.8%) vs 0, P < 0.001]. There were 2 (15.4%) postoperative strokes in the EV group. There were no statistically significant differences in other postoperative complications or hospital length of stay between groups. CONCLUSIONS: KD can be managed using open or EV approaches with low morbidity and mortality. Treatment strategy should depend on clinical presentation and patient factors.

Development of machine learning and natural language processing algorithms for preoperative prediction and automated identification of intraoperative vascular injury in anterior lumbar spine surgery.

BACKGROUND: Intraoperative vascular injury (VI) may be an unavoidable complication of anterior lumbar spine surgery; however, vascular injury has implications for quality and safety reporting as this intraoperative complication may result in serious bleeding, thrombosis, and postoperative stricture. PURPOSE: The purpose of this study was to (1) develop machine learning algorithms for preoperative prediction of VI and (2) develop natural language processing (NLP) algorithms for automated surveillance of intraoperative VI from free-text operative notes. PATIENT SAMPLE: Adult patients, 18 years or age or older, undergoing anterior lumbar spine surgery at two academic and three community medical centers were included in this analysis. OUTCOME MEASURES: The primary outcome was unintended VI during anterior lumbar spine surgery. METHODS: Manual review of free-text operative notes was used to identify patients who had unintended VI. The available population was split into training and testing cohorts. Five machine learning algorithms were developed for preoperative prediction of VI. An NLP algorithm was trained for automated detection of intraoperative VI from free-text operative notes. Performance of the NLP algorithm was compared to current procedural terminology and international classification of diseases codes. RESULTS: In all, 1035 patients underwent anterior lumbar spine surgery and the rate of intraoperative VI was 7.2% (n=75). Variables used for preoperative prediction of VI were age, male sex, body mass index, diabetes, L4-L5 exposure, and surgery for infection (discitis, osteomyelitis). The best performing machine learning algorithm achieved c-statistic of 0.73 for preoperative prediction of VI (https://sorg-apps.shinyapps.io/lumbar_vascular_injury/). For automated detection of intraoperative VI from free-text notes, the NLP algorithm achieved c-statistic of 0.92. The NLP algorithm identified 18 of the 21 patients (sensitivity 0.86) who had a VI whereas current procedural terminologyand international classification of diseases codes identified 6 of the 21 (sensitivity 0.29) patients. At this threshold, the NLP algorithm had a specificity of 0.93, negative predictive value of 0.99, positive predictive value of 0.51, and F1-score of 0.64. CONCLUSION: Relying on administrative procedural and diagnosis codes may underestimate the rate of unintended intraoperative VI in anterior lumbar spine surgery. External and prospective validation of the algorithms presented here may improve quality and safety reporting.

A multi-institutional study of patient-derived gender-based discrimination experienced by resident physicians.

BACKGROUND: This study characterizes prevalence, frequency, and forms of patient-derived gender-based discrimination (GBD) experienced by resident physicians, as well as their experiences witnessing and reporting patient-derived GBD. METHODS: A web-based survey was sent to residents from 12 programs at three academic institutions. RESULTS: Response rate was 47.9% (309/645) with 55.0% of respondents identifying as women. Women were more likely than men to experience patient-derived GBD during residency (100% vs 68.8%, p < 0.001), including inappropriate physical contact, receiving less trust from patients, and being mistaken for a nurse (p < 0.001). While 85.9% of residents personally experienced and 95.0% of residents witnessed patient-derived GBD, only 3.4% of residents formally reported patient-derived GBD. Women were more likely to report negative personal and professional consequences of patient-derived GBD. CONCLUSIONS: Patient-derived GBD is pervasive and disproportionately affects women residents. Current reporting mechanisms are not adequately capturing nor addressing patient-derived GBD.

Not hepatic infarction: Cold quadrate sign.

A 50-year-old male presented with bilateral lower extremity plain is found to have a wedge-shape hypodense region in the hepatic quadrate lobe. The hypoenhancement was thought to be a result of systemic-portal venous shunting due to IVC obstruction, a "cold" version of the classically described hot quadrate sign. Follow-up CT confirmed the diagnosis. Venous drainage pathway for both hot and cold quadrate signs is discussed.