Effectiveness of a native vein arteriovenous fistula tracking system.

OBJECTIVE: This study aims to evaluate the effectiveness of a tracking program on the functional maturation rate of arteriovenous fistula (AVF). METHODS: Two major clinical outcomes (commencement of cannulation and functional maturation) of created AVFs were compared between two cohorts. (i) Cohort 1: historical cohort; (ii) Cohort 2: AVFs created after implementation of the tracking project. Multivariable Cox regression models were used to assess the association between cohort allocation and the two major clinical outcomes. RESULTS: Data of 114 and 141 patients were analyzed respectively from Cohorts 1 (historical data) and 2 (with AVF tracking). After adjustment of covariates in the multivariable analysis, the AVFs created in Cohort 2 were more likely to be cannulated earlier (adjusted HR: 2.82; 95% CI: 1.97-4.05; p < 0.001), compared to those in Cohort 1. Similarly, the AVFs of Cohort 2 patients had significantly higher probability of functional maturation (adjusted HR: 1.81; 95% CI: 1.31-2.48; p < 0.001) than fistulas in Cohort 1. Cannulation was commenced for half of the AVFs by 4.1 months post-creation in the historical cohort (Cohort 1), whereas in the post-tracking cohort, 50% of the AVFs were cannulated by 2.3 months after creation (p < 0.001). It took 5.5 and 4.3 months for 50% of the AVFs created in Cohort 1 and Cohort 2 patients to achieve catheter-free functional maturation, respectively (p = 0.06). CONCLUSION: An AVF tracking program with maturation target for the access surgeons, together with a standardized tracking, feedback, and clinical strategy adjustment system is able to improve the AVF functional maturation rate.

A systematic review and meta-analysis of total endovascular versus hybrid repair for the treatment of thoracoabdominal aortic aneurysms.

OBJECTIVE: Although open repair has been the traditional mainstay therapy for thoracoabdominal aortic aneurysms (TAAAs), it remains a surgical challenge. Recently, hybrid repair (HR) and total endovascular repair (TEVR) have emerged as viable alternatives in treating TAAAs. Thus, we aimed to compare the primary outcomes of in-hospital/30-day mortality, as well as secondary outcomes of postoperative complications including spinal cord ischemia, bowel ischemia, long-term dialysis, myocardial infarction and lower limb ischemia for HR vs TEVR for the treatment of TAAAs. We postulated that TEVR was associated with lower in-hospital and 30-day mortality and postoperative complication rates as compared with HR. METHODS: Four scientific databases were searched from inception to November 18, 2021. Meta-analyses were performed for the primary and secondary outcomes. This study was conducted in adherence to the PRISMA guidelines. RESULTS: The search yielded 3312 articles. After a two-stage selection process, five articles were included for final analysis. The in-hospital/30-day mortality rate for TEVR was significantly lower compared with HR (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.20-0.36; P < .00001). TEVR was also associated with reduced bowel ischemia (OR, 0.22; 95% CI, 0.14 -0.35; P < .00001) and long-term dialysis (OR, 0.22; 95% CI, 0.16-0.29; P < .00001). There was, however, no difference in the incidence of spinal cord ischemia (OR, 1.26; 95% CI, 0.74-2.14; P = .39), stroke (OR, 0.65; 95% CI, 0.10-4.20; P = .65), myocardial infarction (OR, 0.60; 95% CI, 0.17-2.05; P = .41), and lower limb ischemia (OR, 0.67; 95% CI, 0.29-1.55; P = .35). Most study outcomes had low heterogeneity. Findings were also robust to sensitivity analysis. CONCLUSIONS: Compared with the HR, TEVR of TAAAs were associated with lower in-hospital and 30-day mortality, bowel ischemia, and long-term dialysis.

A systematic review and meta-analysis of sirolimus-eluting stents for treatment of below-the-knee arterial disease.

OBJECTIVE: We performed a systematic review and meta-analysis to analyze the efficacy and safety of sirolimus-eluting stents (SESs) in the treatment of below-the-knee (BTK) arterial disease. METHODS: An electronic literature search was conducted from inception to July 24, 2021. Retrospective, prospective, and randomized studies that had used SESs to treat BTK arterial disease and had reported the primary patency, technical success, target lesion revascularization, and/or mortality were included. Meta-analyses of the proportions were conducted to derive pooled summary statistics of the outcomes. Where Kaplan-Meier curves were provided for primary patency, a meta-analysis of the individual patient data was conducted via a graphic reconstruction tool to estimate primary patency at various follow-up points. For studies comparing SESs and bare metal stents (BMSs), a two-stage meta-analysis was performed to compare the 6-month primary patency of SESs vs BMSs. RESULTS: Ten studies across 13 publications, including 995 patients, were retrieved for analysis. In the meta-analysis of proportions, across six studies (n = 339 patients), the pooled 6-month primary patency was 87.3% (95% confidence interval [CI], 81.6%-92.1%). Across seven studies (n = 283 patients), the pooled 6-month mortality was 5.4% (95% CI, 1.4%-11.2%). An individual patient data analysis of three studies (n = 282 patients) yielded a primary patency rate of 95.2% (95% CI, 92.7%-97.8%), 82.8% (95% CI, 78.3%-87.6%), 79.8% (95% CI, 75.0%-85.0%), and 79.8% (95% CI, 75.0%-85.0%) at 6, 12, 18, and 24 months, respectively. The 12-month target lesion revascularization rate across four studies (n = 324 patients) was 9.6% (95% CI, 6.4%-13.4%). In the two-stage meta-analysis of 6-month primary patency across three studies (n = 168 patients), the use of SESs was significantly favored over BMSs (risk ratio, 1.28; 95% CI, 1.12-1.46; P < .001). CONCLUSIONS: The overall evidence suggests that the use of SESs appears to be safe and offers favorable outcomes for BTK arterial disease compared with BMSs.

The Effect of Obesity on Outcomes After Arteriovenous Fistulae Creation: A Systematic Review.

BACKGROUND: Establishing reliable vascular access is critical for hemodialysis in end-stage renal disease (ESRD). In recent years, the global health burden of ESRD has grown, matched by a rise in prevalence of obesity. Currently, more and more arteriovenous fistulae (AVFs) are being created for obese patients with ESRD. This is a growing concern as creating arteriovenous (AV) access in obese ESRD patients can be more challenging and may be associated with poorer outcomes. METHODS: We performed a literature search with multiple electronic databases. We included studies that compared outcomes after autogenous upper extremity AVF creation between obese and nonobese patients. The relevant outcomes were postoperative complications, outcomes related to maturation, outcomes related to patency, and outcomes related to reintervention. RESULTS: We included 13 studies with a total of 305,037 patients. We found a significant association between obesity and poorer early and late AVF maturation. Obesity was also strongly associated with lower primary patency rates and a higher need for reintervention. CONCLUSIONS: This systematic review found that higher body mass index and obesity are associated with poorer AVF maturation outcomes, poorer primary patency, and higher reintervention rates.

Percutaneous decannulation of venoarterial extracorporeal membrane oxygenation using the Manta vascular closure device: A systematic review and meta-analysis.

OBJECTIVES: To perform a systematic review and meta-analysis of the techniques and outcomes associated with percutaneous decannulation of venoarterial extracorporeal membrane oxygenation (VA-ECMO) using the Manta vascular closure device. BACKGROUND: Peripheral VA-ECMO can be used to treat critically ill patients with conditions such as refractory cardiogenic shock. After percutaneous implantation of VA-ECMO, VA-ECMO can also be decannulated completely percutaneously by using a vascular closure device. The Manta vascular closure device is a dedicated device used in the closure of large-bore arteriotomies by sandwiching the arteriotomy with an intra-arterial toggle and an extraluminal collagen plug. METHODS: We performed a thorough literature search using various electronic databases. We included studies that reported outcomes after peripheral femorofemoral VA-ECMO decannulation with the Manta vascular closure device. We performed a meta-analysis of proportions on outcome measures, including technical success, bleeding complications, vascular complications, wound complications, major amputation, and procedural-related deaths. RESULTS: We included seven studies with a total of 116 patients. The overall technical success of percutaneous decannulation of VA-ECMO with the Manta vascular closure device was 93.7%. The overall incidence of bleeding, vascular and wound complications was 1.7%, 13.8%, and 3.4%, respectively. No patient required lower limb amputation or died due to VA-ECMO decannulation. CONCLUSION: Percutaneous decannulation with the Manta vascular closure device is an effective and safe procedure that should be considered in suitable patients on VA-ECMO.

National Rates of Lower Extremity Amputation in People With and Without Diabetes in a Multi-Ethnic Asian Population: a Ten Year Study in Singapore.

OBJECTIVE: Population level data from Asia on amputation rates in people with and without diabetes are extremely limited. Hence it is unclear how the rising diabetes prevalence in Asia has affected the amputation burden. The present study examined national amputation rates in people with and without diabetes in Singapore from 2008 to 2017 in the context of increasing diabetes prevalence and health system changes. METHODS: This was a retrospective observational study using national population data for ages 16 - 100 years obtained from the Ministry of Health Singapore administrative datasets. Age sex standardised major and toe/ray amputation rates per 100 000 people with diabetes and per 100 000 people without diabetes were calculated. Rates were calculated overall and in each ethnic group (Chinese, Malay, Indian, Others), with trends over time calculated using joinpoint trend analysis. In addition, age specific rates, relative risk (RR) of amputation in diabetics compared with non-diabetics and proportion of amputations in the population attributable to diabetes were also calculated. RESULTS: Between 2008 and 2017, the database included 3.6 million unique individuals, of whom 75% were Chinese, 8.6% Malay, 7.9% Indian, and 8.4% Others. Of those, 413 486 (11%) had diabetes. Major amputation rates in people with diabetes remained stable (2008: 99.5/100 000; 2017: 95.0/100 000 people with diabetes, p = .91) as did toe/ray amputation rates. Rates in people without diabetes were substantially lower, with major amputation rates decreasing significantly (2008: 3.0/100 000; 2017: 2.1/100 000 people without diabetes, 3% annual reduction, p = .048). Diabetes related amputation rates were highest in Malays and lowest in Chinese. Diabetes related major amputation rates declined significantly among Chinese (3.1% annual reduction, p < .038). While the RR for amputations in diabetes remained stable, the proportion of major amputations attributable to diabetes increased from 63.6% in 2008 to 81.7% in 2017 (3% annual increase, p = .003). CONCLUSION: Diabetes related major and toe/ray amputation rates have remained stable but relatively high in Singapore compared with other countries, and the proportion of amputations attributable to diabetes has increased over time. More research is needed to understand the aetiopathological, sociocultural, and health system factors that may underlie the continued high rates of diabetes related amputations in this population.

Frailty scoring in vascular and endovascular surgery: A systematic review.

One in 10 independently living adults aged 65 years old and older is considered frail, and frailty is associated with poor postoperative outcomes. This systematic review aimed to examine the association between frailty assessments and postoperative outcomes in patients with vascular disease. Electronic databases - MEDLINE, Embase, and the Cochrane Library - were searched from inception until January 2022, resulting in 648 articles reviewed for potential inclusion and 16 studies selected. Demographic data, surgery type, frailty measure, and postoperative outcomes predicted by frailty were extracted from the selected studies. The risk of bias was assessed using the Newcastle-Ottawa Scale. The selected studies (mean age: 56.1-76.3 years) had low-to-moderate risk of bias and included 16 vascular (elective and nonelective) surgeries and eight frailty measures. Significant associations (p < 0.05) were established between mortality (30-day, 90-day, 1-year, 5-year), 30-day morbidity, nonhome discharge, adverse events, failure to rescue, patient requiring care after discharge, and amputation following critical limb ischaemia. The strongest evidence was found between 30-day mortality and frailty. Composite 30-day morbidity and mortality, functional status at discharge, length of stay, spinal cord deficit, and access site complications were found to be nonsignificantly associated with frailty. With frailty being significantly associated with several adverse postoperative outcomes, preoperative frailty assessments can potentially be clinically useful in helping practitioners predict and guide the pre-, peri-, and postoperative management of frail with vascular disease.

Hybrid type II and frozen elephant trunk in acute Stanford type A aortic dissections.

Objectives. Composite frozen elephant trunk is an increasingly popular solution for complex aortic pathologies. This review aims to compare outcomes of zone 0 type II hybrid (hybrid II) with the composite frozen elephant trunk (FET) technique in managing acute Stanford type A aortic dissections. Methods. PubMed and Embase were systematically searched using PRISMA protocol. 11 relevant studies describing the outcomes of hybrid II arch repair and FET techniques in patients with type A aortic dissection were included in the meta-analysis. The study focused on early post-operative 30-day outcomes analysing mortality, stroke, spinal cord injury, renal impairment requiring dialysis, bleeding and lung infection. Results. 1305 patients were included in the analysis - 343 receiving hybrid II repair and 962 treated with the FET. Meta-analysis of proportions showed Hybrid II was associated with less early mortality [5.0 (CI 3.1-7.8) vs 8.1 (CI 6.5-10.0) %], stroke [2.3 (CI 1.1-4.6) vs 7.0 (CI 5.5-8.8) %], spinal cord injury [2.0 (CI 0.9-4.3) vs 3.8 (CI 2.8-5.3) %], renal impairment requiring dialysis [7.9 (CI 5.5-11.2) vs 11.8 (CI 9.8-14.0) %], reoperation for bleeding [3.9 (CI 1.8-8.4) vs 10.6 (CI 8.1-13.8) %] and lung infection [14.8 (CI 10.8-20.0) vs 20.7 (CI 16.9-25.1) %]. Conclusion. Hybrid II should be considered in favour of FET technique in acute Stanford type A dissection patients who are at higher risk due to age and comorbidities.

Lobar versus Sublobar Resection in the Elderly for Early Lung Cancer: A Meta-Analysis.

OBJECTIVES: We performed a systematic review and meta-analysis of outcomes of lobectomy versus sublobar resection in elderly patients (≥65) with stage 1 nonsmall cell lung carcinoma (NSCLC). METHODS: We searched for relevant articles using a set of inclusion and exclusion criteria. Meta-analytic techniques were applied. RESULTS: Twelve studies (n = 5834) were chosen. Our results indicate that in the elderly, lobectomy for stage 1 NSCLC confers a survival advantage over sublobar resection. Lobectomy patients had a lower risk of death within 5 years and lower odds of local cancer recurrence. Our results show that lobectomy had a better 5-year cancer-specific survival and 5-year disease-free survival that trended toward significance. The sublobar resection group showed better 30-day operative mortality that trended toward significance. Subgroup analysis of stage 1A cancer demonstrated no difference in 5-year overall survival rates. However, for stage 1B tumors 5-year overall survival favored lobectomy. CONCLUSION: Lobectomy for stage 1 NSCLC in elderly patients is superior to sublobar resection in terms of survival and cancer recurrence and should be afforded where possible. For stage 1A tumors, sublobar resection is noninferior and may be considered. Further randomized controlled trials in this topic is required.

Partial Versus Complete Thymectomy in Non-Myasthenic Patients With Thymoma: A Systematic Review and Meta-Analysis of Clinical Outcomes.

OBJECTIVE: The optimal extent of surgical resection for non-myasthenic patients with thymoma is controversial. The objective of this meta-analysis was to compare complete to partial thymectomy in non-myasthenic patients for oncological and postoperative clinical outcomes. METHODS: We performed a PubMed and EMBASE search (from inception to January 2020) for English-language studies directly comparing partial thymectomy (thymomectomy) to complete thymectomy for thymoma resection. Clinical endpoints studied included overall and disease-free survival, Masaoka and World Health Organization staging, adjuvant therapy, postoperative complications, postoperative drainage, length of hospital stay, thymoma-related deaths, postresection development of myasthenia gravis, incomplete resection, and recurrence. Random effects meta-analyses across all clinical endpoints was done. RESULTS: There was no statistically significant difference between the two approaches with regard to recurrence (odds ratio [OR], 1.22; 95% confidence interval [CI], 0.78-1.92), completeness of resection (OR, 1.17; 95% CI, 0.66-2.10), adjuvant therapy (OR, 0.71; 95% CI, 0.40-1.26), or thymoma-related deaths (OR, 0.76; 95% CI, 0.12-4.66). There was a statistically significant decrease in postoperative complications (OR, 0.61; 95% CI, 0.39-0.97), drainage (mean difference [MD], -0.99; 95% CI, -1.98 to -0.01), and length of hospital length (MD, -1.88; 95% CI, -3.39 to -0.36) with partial thymectomy. CONCLUSIONS: The evidence appeared to suggest that partial thymectomy is oncologically equivalent to complete thymectomy for non-myasthenic patients with early-stage thymoma. There is an additional advantage of reduced postoperative complications and decreased length of hospital stay with partial thymectomy.

Diabetes-related lower extremity complications in a multi-ethnic Asian population: a 10 year observational study in Singapore.

AIMS/HYPOTHESIS: Diabetes progression and complication risk are different in Asian people compared with those of European ancestry. In this study, we sought to understand the epidemiology of diabetes-related lower extremity complications (DRLECs: symptomatic peripheral arterial disease, ulceration, infection, gangrene) and amputations in a multi-ethnic Asian population. METHODS: This was a retrospective observational study using data obtained from one of three integrated public healthcare clusters in Singapore. The population consisted of individuals with incident type 2 diabetes who were of Chinese, Malay, Indian or Other ethnicity. We examined incidence, time to event and risk factors of DRLECs and amputation. RESULTS: Between 2007 and 2017, of the 156,593 individuals with incident type 2 diabetes, 20,744 developed a DRLEC, of whom 1208 underwent amputation. Age- and sex-standardised incidence of first DRLEC and first amputation was 28.29/1000 person-years of diabetes and 8.18/1000 person-years of DRLEC, respectively. Incidence of both was highest in individuals of Malay ethnicity (DRLEC, 36.09/1000 person-years of diabetes; amputation, 12.96/1000 person-years of DRLEC). Median time from diabetes diagnosis in the public healthcare system to first DRLEC was 30.5 months for those without subsequent amputation and 10.9 months for those with subsequent amputation. Median time from DRLEC to first amputation was 2.3 months. Older age (p < 0.001), male sex (p < 0.001), Malay ethnicity (p < 0.001), Indian ethnicity (p = 0.014), chronic comorbidities (nephropathy [p < 0.001], heart disease [p < 0.001], stroke [p < 0.001], retinopathy [p < 0.001], neuropathy [p < 0.001]), poorer or missing HbA1c (p < 0.001), lower (p < 0.001) or missing (p = 0.002) eGFR, greater or missing BMI (p < 0.001), missing LDL-cholesterol (p < 0.001) at diagnosis, and ever-smoking (p < 0.001) were associated with higher hazard of DRLEC. Retinopathy (p < 0.001), peripheral vascular disease (p < 0.001), poorer HbA1c (p < 0.001), higher (p = 0.009) or missing (p < 0.001) LDL-cholesterol and missing BMI (p = 0.008) were associated with higher hazard of amputation in those with DRLEC. Indian ethnicity (p = 0.007) was associated with significantly lower hazard of amputation. CONCLUSIONS/INTERPRETATION: This study has revealed important ethnic differences in risk of diabetes-related lower limb complications, with Malays most likely to progress to DRLEC. Greater research efforts are needed to understand the aetiopathological and sociocultural processes that contribute to the higher risk of lower extremity complications among these ethnic groups.

A scoping review of vascular surgery education in the medical school curriculum.

OBJECTIVE: Despite the high burden of vascular disease that is assessed, investigated, and managed by generalists, no specific medical school curriculum is in use for vascular surgery (VS). In the present scoping review, we aimed to map the available evidence on the provision of VS education in the medical school curriculum worldwide. METHODS: The present review was conducted in accordance with the PRISMA (preferred reporting items for systematic reviews and meta-analysis) extension for scoping reviews. The inclusion criterion was reported research studies on VS education in the medical curriculum. RESULTS: A total of 20 studies were included. Three main themes were identified. VS was perceived as an essential part of the general medical student curriculum by VS applicants. Exposure to VS varied considerably, and students generally expressed a need for an increase in VS coverage. The most important positive determinants when choosing VS as a career were having a VS mentor, the technical aspects of VS, and participation in a VS rotation. Frequently cited deterrents were the long training time and demanding lifestyle potentially compromising family life. CONCLUSIONS: The present scoping review has provided a starting point to better understand the provision of VS education in medical schools across the world. Our review has demonstrated the variability in VS exposure at medical school and described students' sentiments toward VS. We have highlighted the need to determine whether the current curricula are adequate from the perspective of multiple stakeholders (eg, vascular surgeons, educators, general practitioners, a variety of specialists) with a crucial role in the treatment of patients with vascular conditions.

A systematic review of brachial artery ligation as a safe and feasible option in the management of arteriovenous dialysis access infection.

OBJECTIVE: Creation of good long-term arteriovenous access is essential in patients requiring hemodialysis for end-stage renal failure. However, arteriovenous grafts or fistulae can be complicated by infection that may require emergency surgery. For infections that involve the brachial artery anastomosis, or if total graft explantation is indicated, brachial artery repair or reconstruction is often required. An alternative management strategy would be brachial artery ligation (BAL). We performed a systematic review to evaluate the outcomes of BAL that has been performed for infected arteriovenous grafts or fistulae. METHODS: A thorough literature search was conducted using various electronic databases. We included articles that reported outcomes of BAL performed for infected arteriovenous grafts or fistulae. The primary outcome was the incidence of upper limb ischemia after BAL. Secondary outcomes were the need for urgent revascularization, need for upper limb amputation, and incidence of postoperative neurological deficit after BAL. RESULTS: A total of five studies with a total of 125 patients were included in our systematic review. BAL was performed for infected arteriovenous grafts or fistulae for all studies. Follow-up period ranged from 1 to 27 months. The incidence of upper limb ischemia after BAL was low. Only a single study reported three patients who developed upper limb ischemia. Two patients required urgent revascularization, and one patient required forearm amputation after proximal ligation. All studies reported clearance of infection with no recurrence. CONCLUSIONS: Distal BAL may be performed safely for patients with infected arteriovenous fistulae or grafts with low risk of upper limb ischemia, postoperative neurological deficit, and recurrent infection.

Zone 1 Aortic Arch Hybrid Endovascular Repair with Extra-anatomical Bypass: A Meta-analysis.

BACKGROUND: The aim of this meta-analysis is to determine the morbidity and mortality outcomes of adult patients with aortic arch disease managed with extra-anatomical bypass avoiding median sternotomy and cardiopulmonary bypass, with simultaneous or staged hybrid zone 1 endovascular aortic repair. METHODS: Systematic literature searches of the MEDLINE, EMBASE, and Cochrane databases were carried out to identify relevant studies on zone 1 hybrid arch repair. Extracted data were analyzed by random effects models. Primary outcomes included 30-day or in-hospital mortality. Longitudinal survival was analyzed up to 7 years from date of operation. Secondary outcomes included in-hospital morbidity, as well as late endoleak and reintervention. RESULTS: Twenty studies incorporating 348 patients were included. In-hospital or 30-day mortality was 10.1% (95% confidence interval, 6.7-14.9%). Overall operative technical success was 89.8% (83.7-93.8%). Early type 1 endoleak rate was 14.0% (7.4-24.7%). Stroke prevalence was 9.5% (6.1-14.3%). Spinal cord paraplegia prevalence was 3.8% (1.9-7.6%). Retrograde aortic dissection prevalence was 4.1% (1.5-10.6%). Survival at 1 year postoperatively was 77.2% (66.1-85.4%). Survival at 3 years postoperatively was 73.7% (59.2-84.4%). Survival beyond 4 years postoperatively (range 58-80 months) was 65.9% (53.6-76.4%). Late type 1 endoleak prevalence was 11.8% (5.5-23.7%). Overall rate of reintervention was 11.6% (6.4-20.1%). CONCLUSIONS: Zone 1 hybrid repair has evidence for satisfactory short- and long-term morbidity/mortality outcomes and may be considered as an alternative approach to aortic arch disease.

Vascular e-Learning During the COVID-19 Pandemic: The EL-COVID Survey.

BACKGROUND: The corona virus disease (COVID-19) pandemic has radically changed the possibilities for vascular surgeons and trainees to exchange knowledge and experience. The aim of the present survey is to inventorize the e-learning needs of vascular surgeons and trainees as well as the strengths and weaknesses of vascular e-Learning. METHODS: An online survey consisting of 18 questions was created in English, with a separate bilingual English-Mandarin version. The survey was dispersed to vascular surgeons and trainees worldwide through social media and via direct messaging from June 15, 2020 to October 15, 2020. RESULTS: Eight hundred and fifty-six records from 84 different countries could be included. Most participants attended several online activities (>4: n = 461, 54%; 2-4: n = 300, 35%; 1: n = 95, 11%) and evaluated online activities as positive or very positive (84.7%). In deciding upon participation, the topic of the activity was most important (n = 440, 51.4%), followed by the reputation of the presenter or the panel (n = 178, 20.8%), but not necessarily receiving accreditation or certification (n = 52, 6.1%). The survey identified several shortcomings in vascular e-Learning during the pandemic: limited possibility to attend due to lack of time and increased workload (n = 432, 50.5%), no protected/allocated time (n = 488, 57%) and no accreditation or certification, while technical shortcomings were only a minor problem (n = 25, 2.9%). CONCLUSIONS: During the COVID-19 pandemic vascular e-Learning has been used frequently and was appreciated by vascular professionals from around the globe. The survey identified strengths and weaknesses in current e-Learning that can be used to further improve online learning in vascular surgery.

Anticoagulation After Isolated Mitral Valve Repair: A Systematic Review and Meta-Analysis of Clinical Outcomes.

Recommendations from international guidelines on optimal thromboprophylaxis after mitral repair are controversial and based on underpowered observational studies. This study aimed to evaluate the prophylactic use of warfarin after isolated mitral valve repair (MVr). A PubMed, EMBASE and Scopus search for studies in English on postoperative thromboprophylaxis for isolated MVr published to February 2020 was performed. The analysis excluded all studies with combined operations, mitral valve replacement and preoperative or postoperative atrial fibrillation. Clinical endpoints that were studied were thromboembolic events, bleeding complications and mortality. Random effects meta-analyses of the effect of postoperative warfarin use as compared with no warfarin use across all clinical endpoints was conducted. Warfarin use did not confer benefit in terms of thromboembolic prophylaxis after isolated MVr in patients without atrial fibrillation (OR, 0.97; 95% CI, 0.72-1.31). At the same time, it did not increase the risk of bleeding complications (OR, 1.10; 95% CI, 0.53-2.30) or affect overall survival during the follow-up period of the included studies (OR, 1.06; 95% CI, 0.28-4.05). To conclude, warfarin use is not necessary for patients after isolated MVr who remain in sinus rhythm. Recommendations from international guidelines may need to be revisited for this group of patients.

Vascular Complications of Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-Regression Analysis.

OBJECTIVES: Perform a systematic review and meta-analysis of vascular complications associated with extracorporeal membrane oxygenation and identify prognostic and predictive factors. DATA SOURCES: Systematic search for publications reporting vascular complications on extracorporeal membrane oxygenation, published from 1972 to January 31, 2020, was conducted via PubMed, Scopus, and Embase. STUDY SELECTION: Of 4,076 references screened, 47 studies with 6,583 patients were included in final analyses. Studies with fewer than 10 patients were excluded. DATA EXTRACTION: Relevant data, including demographics, comorbidities, extracorporeal membrane oxygenation and cannulation characteristics, occurrence rates of early and late vascular complications, patient outcomes, and use of distal perfusion cannula, were extracted from selected articles into an excel sheet specifically designed for this review. DATA SYNTHESIS: Random-effects meta-analyses and meta-regression analyses were undertaken. Overall pooled estimate of vascular complications in our meta-analysis was 29.5% (95% CI, 23.6-35.9%). Two-thousand three-hundred forty-seven vascular complications in 6,124 venoarterial extracorporeal membrane oxygenation patients compared with 95 in 459 venovenous extracorporeal membrane oxygenation patients (odds ratio, 2.35; 95% CI, 1.87-2.96; p < 0.0001) were analyzed. Successful weaning off extracorporeal membrane oxygenation occurred in 60.6% of pooled patients; 46.2% were eventually discharged. Pooled prevalences of vascular complications like significant bleeding, limb ischemia, and cannula site bleeding were 15.4% (95% CI, 8.6-23.7%), 12.6% (95% CI, 10.0-15.5%), and 12.6% (95% CI, 9.6-18.5%), respectively. Meta-analysis showed that the use of distal perfusion cannula was associated with lower odds of limb ischemia (odds ratio, 1.93; 95% CI, 1.17-2.47; p = 0.03) Meta-regression showed that male sex, smoking, advanced age, and comorbidities contributed to higher in-hospital mortality, while distal perfusion cannula was protective. CONCLUSIONS: Nearly a third of patients on extracorporeal membrane oxygenation develop vascular complications; elderly males with comorbidities appear vulnerable. The use of distal perfusion cannulas caused significant reduction in limb ischemia and mortality.

A systematic review of the impact of preoperative exercise for patients with abdominal aortic aneurysm.

BACKGROUND: Abdominal aortic aneurysm (AAA) surgery carries significant risk of morbidity and mortality. Preoperative exercise may improve the physical fitness capacity of patients with AAA as well as postoperative outcomes. METHODS: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search was performed on MEDLINE, Embase, and Cochrane Library for relevant studies. A methodologic assessment of included studies was conducted using the Physiotherapy Evidence Database (PEDro) scale. RESULTS: Seven studies (six randomized controlled trials and one retrospective cohort study) were included. The overall quality of studies was assessed to range from fair to good. Three studies included AAA patients without indication for surgery, whereas four other studies included AAA patients awaiting surgical repair. One study implemented an inspiratory muscle training program; five studies implemented a continuous moderate-intensity exercise regimen; one study implemented a high-intensity interval training program. Overall compliance with the exercise regimen was high (94% in those not waiting for surgery; 75.8% to 82.3% in those waiting for surgery). In patients not awaiting surgery, preoperative exercise may improve physical fitness parameters including ventilatory threshold (P = .016 at 12 weeks; P = .09 at 12 months) and anaerobic threshold (10% increase; P = .007) but not peak oxygen consumption (P = .183 at 12 weeks; P = .29 at 12 months). In patients awaiting surgery, one study demonstrated a statistically significant improvement in peak oxygen consumption (difference, 1.6 mL/kg/min; P = .004) and anaerobic threshold (difference, 1.9 mL/kg/min; P = .012) for patients who exercised. In terms of postoperative outcomes, exercise may reduce the risk of cardiac, renal, and respiratory complications, although only in those who undergo open surgery. Only patients who underwent endovascular repair had a shorter length of hospital stay when preoperative exercise was conducted. CONCLUSIONS: Despite the encouraging evidence of preoperative exercise for AAA patients, it remains premature to recommend it as a preoperative intervention. Given the heterogeneity of reported outcomes, future studies should consider conducting well-designed randomized controlled trials with standardized reporting outcomes and definitions.

Experience from a Singapore tertiary hospital with restructuring of a vascular surgery practice in response to national and institutional policies during the COVID-19 pandemic.

Singapore was one of the first countries to be affected by COVID-19, with the index patient diagnosed on January 23, 2020. For 2 weeks in February, we had the highest number of COVID-19 cases behind China. In this article, we summarize the key national and institutional policies that were implemented in response to COVID-19. We also describe in detail, with relevant data, how our vascular surgery practice has changed because of these policies and COVID-19. We show that with a segregated team model, the vascular surgery unit can still function while reducing risk of cross-contamination. We explain the various strategies adopted to reduce outpatient and inpatient volume. We provide a detailed breakdown of the type of vascular surgical cases that were performed during the COVID-19 pandemic and compare it with preceding months. We discuss our operating room and personal protective equipment protocols in managing a COVID-19 patient and share how we continue surgical training amid the pandemic. We also discuss the challenges we might face in the future as COVID-19 regresses.

Managing central venous access during a health care crisis.

OBJECTIVE: During the COVID-19 pandemic, central venous access line teams were implemented at many hospitals throughout the world to provide access for critically ill patients. The objective of this study was to describe the structure, practice patterns, and outcomes of these vascular access teams during the COVID-19 pandemic. METHODS: We conducted a cross-sectional, self-reported study of central venous access line teams in hospitals afflicted with the COVID-19 pandemic. To participate in the study, hospitals were required to meet one of the following criteria: development of a formal plan for a central venous access line team during the pandemic; implementation of a central venous access line team during the pandemic; placement of central venous access by a designated practice group during the pandemic as part of routine clinical practice; or management of an iatrogenic complication related to central venous access in a patient with COVID-19. RESULTS: Participants from 60 hospitals in 13 countries contributed data to the study. Central venous line teams were most commonly composed of vascular surgery and general surgery attending physicians and trainees. Twenty sites had 2657 lines placed by their central venous access line team or designated practice group. During that time, there were 11 (0.4%) iatrogenic complications associated with central venous access procedures performed by the line team or group at those 20 sites. Triple lumen catheters, Cordis (Santa Clara, Calif) catheters, and nontunneled hemodialysis catheters were the most common types of central venous lines placed by the teams. Eight (14%) sites reported experience in placing central venous lines in prone, ventilated patients with COVID-19. A dedicated line cart was used by 35 (59%) of the hospitals. Less than 50% (24 [41%]) of the participating sites reported managing thrombosed central lines in COVID-19 patients. Twenty-three of the sites managed 48 iatrogenic complications in patients with COVID-19 (including complications caused by providers outside of the line team or designated practice group). CONCLUSIONS: Implementation of a dedicated central venous access line team during a pandemic or other health care crisis is a way by which physicians trained in central venous access can contribute their expertise to a stressed health care system. A line team composed of physicians with vascular skill sets provides relief to resource-constrained intensive care unit, ward, and emergency medicine teams with a low rate of iatrogenic complications relative to historical reports. We recommend that a plan for central venous access line team implementation be in place for future health care crises.