Amputated Digit Replantations: Critical Digit Ischemia Timing, Temperature, and Other Predictors of Survival.

INTRODUCTION: A common consideration for replantation success is the ischemia time following injury and the preservation temperature. A classic principle within the hand surgery community describes 12 hours of warm ischemia and 24 hours of cold ischemia as the upper limits for digit replantation; however, these limits are largely anecdotal and based on older studies. We aimed to compare survival data from the large body of literature to aid surgeons and all those involved in the replantation process in hopes of optimizing success rates. METHODS: The PubMed database was queried on April 4th, 2023, for articles that included data on digit replantation survival in terms of temperature of preservation and ischemia time. All primary outcomes were analyzed with the Mantel-Haenszel method within a random effects model. Secondary outcomes were pooled and analyzed using the chi-square statistic. Statistical analysis and forest plot generation were completed with RevMan 5.4 software with odds ratios calculated within a 95% confidence interval. RESULTS: Our meta-analysis identified that digits preserved in cold ischemia for over 12 hours had significantly higher odds of replantation success than the amputated digits replanted with 0-12 hours of warm ischemia time ( P ≤ 0.05). The odds of survival in the early (0-6 hours) replantation group were around 40% greater than the later (6-12 hours) replantation group ( P ≤ 0.05). Secondary outcomes that were associated with higher survival rates included a clean-cut amputation, increased venous and arterial anastomosis, a repair that did not require a vein graft, and replants performed in nonsmokers ( P ≤ 0.05). DISCUSSION: Overall, these findings suggest that when predicting digit replantation success, time is of the essence when the digit has yet to be preserved in a cold environment. This benefit, however, is almost completely diminished when the amputated digit is appropriately maintained in a cold environment soon after injury. In conclusion, our results suggest that there is potential for broadening the ischemia time limits for digit replant survival outlined in the literature, particularly for digits that have been stored correctly in cold ischemia.

Surgical choice for the treatment of partial intestinal ischemic necrosis caused by acute type a aortic dissection combined with malperfusion of superior mesenteric artery.

Acute type A aortic dissection is a severe cardiovascular disease characterized by rapid onset and high mortality. Traditionally, urgent open aortic repair is performed after admission to prevent aortic rupture and death. However, when combined with malperfusion syndrome, the low perfusion of the superior mesenteric artery can further lead to intestinal necrosis, significantly impacting the surgery's prognosis and potentially resulting in adverse consequences, bringing. This presents great significant challenges in treatment. Based on recent domestic and international research literature, this paper reviews the mechanism, current treatment approaches, and selection of surgical methods for poor organ perfusion caused by acute type A aortic dissection. The literature review findings suggest that central aortic repair can be employed for the treatment of acute type A aortic dissection with inadequate perfusion of the superior mesenteric artery. The superior mesenteric artery can be windowed and (/or) stented, followed by delayed aortic repair. Priority should be given to revascularization of the superior mesenteric artery, followed by central aortic repair. During central aortic repair, direct blood perfusion should be performed on the distal true lumen of the superior mesenteric artery, leading to resulting in favorable therapeutic outcomes. The research results indicate that even after surgical aortic repair, intestinal ischemic necrosis may still occur. In such cases, prompt laparotomy and necessary necrotic bowel resection are crucial for saving the patient's life.

Enhanced external counterpulsation treatment improves multi-organ hemodynamics for postoperative liver transplantation patient. A case report.

INTRODUCTION: Post liver transplantation (LT) patients endure high morbidity rate of multi-organ ischemic symptoms following reperfusion. We hypothesize that enhanced external counterpulsation (EECP) as a typical non-invasive assisted circulation procedure, which can efficiently inhibit the relative ischemic symptoms via the systemic improvement of hemodynamics. CASE PRESENTATION: A 51-year-old male patient, 76 kg, 172 cm, received orthotopic LT surgery for viral hepatitis B induced acute-on-chronic liver failure hepatic failure. His medical records revealed ischemic symptoms in multi-organ at the time of hospital discharge, including headache, refractory insomnia, abdominal paralysis, and lower limb pain. The EECP treatment was introduced for assisted rehabilitation and to improve the postoperative quality of life. Doppler Ultrasound examination showed significant augmentation of blood flow volume in the carotid arteries, the hepatic artery, the portal vein and the femoral artery during EECP intervention. A standard 35-hour EECP treatment led to significant improvement in quality of life, e.g. sleep quality and walking ability. CONCLUSION: We report a case of multi-organ ischemic symptoms in a post LT patient. EECP treatment can significantly improve the quality of life via the systematic promotion of hemodynamics.

Alternative vein bypass in octogenarians with chronic limb-threatening ischaemia.

BACKGROUND: Octogenarians are regarded as one of the frailest patient groups among the chronic limb-threatening ischaemia population with high perioperative morbidity and mortality rates. As a result, alternative vein bypass surgery in the absence of sufficient great saphenous vein is often not considered as a potential treatment option. The aim of this study was to compare the results of octogenarians undergoing alternative vein bypass surgery due to chronic limb-threatening ischaemia to younger patients. METHODS: A single-centre retrospective analysis of patients undergoing bypass surgery for chronic limb-threatening ischaemia with alternative autologous vein grafts between 1997 and 2018 was performed. Patients aged over 80 years were compared with those under 80 years. Graft patency rates were assessed and a risk factor analysis for limb loss was performed. RESULTS: In total, 592 patients underwent bypass surgery during the study interval. Twenty-one per cent (n = 126) of patients were 80 years or older. At 4 years, primary, primary-assisted and secondary patency as well as limb salvage rates were not significantly different between the two groups (46% versus 50%, 60% versus 66%, 69% versus 72%, 72% versus 77%, for octogenarians versus non-octogenarians respectively). Major amputations were performed in 27 (21%) octogenarians and 91 (20%) non-octogenarians (P = 0.190). No higher 30-day and long-term mortality rates nor morbidity rates were detected in the octogenarian group with a median follow-up time of 27 (interquartile range 12-56) months. Minor amputation, the reason for alternative vein grafts, as well as the profunda femoris artery as proximal origin of the bypass were risk factors for limb loss in the postoperative course. CONCLUSION: Alternative vein bypass surgery in octogenarians with chronic limb-threatening ischaemia is safe and effective in terms of patency rates, limb salvage and survival compared with younger patients in the absence of sufficient great saphenous vein. Age alone should not be a deterrent from performing bypass surgery.

The Utility of Prevena Negative Pressure Wound Therapy on Groin Incisions for Critical Limb-Threatening Ischemia: A Single Institution Experience.

BACKGROUND: Incisional negative pressure wound therapy (iNPWT) is an adjunctive treatment that uses constant negative pressure suction to facilitate healing. The utility of this treatment modality on vascular operations for critical limb-threatening ischemia (CLTI) has yet to be elucidated. This study compares the incidence of postoperative wound complications between the Prevena Incision Management System, a type of iNPWT, and standard wound dressings for vascular patients who also underwent plastic surgery closure of groin incisions for CLTI. METHOD: We performed a retrospective cohort study of 40 patients with CLTI who underwent 53 open vascular surgeries with subsequent sartorius muscle flap closure. Patient demographics, intraoperative details, and wound complications were measured from 2015 to 2018 at the University of California San Francisco. Two cohorts were generated based on the modality of postoperative wound management and compared on wound healing outcomes. RESULTS: Of the 53 groin incisions, 29 were managed with standard dressings, and 24 received iNPWT. Patient demographics, comorbidities, and operative characteristics were similar between the 2 groups. Patients who received iNPWT had a significantly lower rate of infection (8.33% vs 31.0%, P = 0.04) and dehiscence (0% vs 41.3%, P < 0.01). Furthermore, the iNPWT group had a significantly lower rate of reoperation (0% vs 17.2%, P = 0.03) for wound complications within 30 days compared with the control group and a moderately reduced rate of readmission (4.17% vs 20.7%, P = 0.08). CONCLUSIONS: Rates of infection, reoperation, and dehiscence were significantly reduced in patients whose groin incisions were managed with iNPWT compared with standard wound care. Readmission rates were also decreased, but this difference was not statistically significant. Our results suggest that implementing iNPWT for the management of groin incisions, particularly in patients undergoing vascular operations for CLTI, may significantly improve clinical outcomes.

Infrapopliteal Bypass In Patients On Dialysis: Patency And Survival.

INTRODUCTION: Portugal has one of the highest prevalence of patients on a regular dialysis program. This population has a higher incidence of peripheral arterial disease with higher rates of postoperative morbidity and mortality. Our goal was to compare outcomes between dialysis and non-dialysis patients with chronic limb threatening ischemia (CLTI) submitted to infrapopliteal bypass. MATERIALS AND METHODS: A retrospective single-center study of infrapopliteal bypass for CLTI was performed between 2012 and 2019. Patients were divided in two groups based on dialysis status (group 1 incorporated patients on dialysis). Primary end point was 1-year freedom from CLTI. Secondary end points were limb-salvage, survival and primary (PP) and tertiary patency (TP) rates at 3 years of follow-up. RESULTS: A total of 352 infrapopliteal bypasses were performed in 310 patients with CLTI. Fourteen percent of the revascularizations were performed on dialysis patients (48/352). Median age was 73 years (interquartile range - IQR 15) and 74% (259/352) were male. Median follow-up was 26 months (IQR 42). Overall, 92% (325/352) had tissue loss and 44% (154/352) had some degree of infection. The majority of revascularization procedures were performed with vein grafts (61%, 214/352). The 30-day mortality was 4% (11/310), with no difference between groups (p = 0.627). Kaplan-Meier analysis showed no difference between groups regarding freedom from CLTI (76% vs. 79%; HR 0.96, CI 0.65-1.44, p=0.857), limb-salvage (70% vs. 82%; HR 1.40, CI 0.71-2.78, p=0.327) and survival (62% vs. 64%; HR 1.08, CI 0.60-1.94, p=0.799). PP rates were 39% in group 1 and 64% in group 2 (HR 1.71, CI 1.05-2.79, p=0.030). TP rates were not different between groups (57% and 78%; HR 1.79, CI 0.92-3.47, p=0.082). CONCLUSION: Infrapopliteal bypass for CLTI, on dialysis patients, resulted in lower PP rates. No differences were observed in freedom from CLTI, TP, limb salvage and survival.

A visceral organ function-focused therapeutic strategy using a 6-hour time window for patients with acute type a aortic dissection complicated by mesenteric malperfusion.

BACKGROUND: Acute type A aortic dissection (ATAAD) complicated by mesenteric malperfusion is a critical and complicated condition. The optimal treatment strategy remains controversial, debate exists as to whether aortic dissection or mesenteric malperfusion should be addressed first, and the exact time window for mesenteric ischemia intervention is still unclear. To solve this problem, we developed a new concept based on the pathophysiological mechanism of mesenteric ischemia, using a 6-hour time window to divide newly admitted patients by the time from onset to admission, applying different treatment protocols to improve the clinical outcomes of patients with ATAAD complicated by mesenteric malperfusion. METHODS: This was a retrospective study that covered a five-year period. From July 2018 to December 2020(phase I), all patients underwent emergency open surgery. From January 2021 to June 2023(phase II), patients with an onset within 6 h all underwent open surgical repair, followed by immediately postoperative examination if the malperfusion is suspected, while the restoration of mesenteric perfusion and visceral organ function was performed first, followed by open repair, in patients with an onset beyond 6 h. RESULTS: There were no significant differences in baseline and surgical data. In phase I, eleven patients with mesenteric malperfusion underwent open surgery, while in phase II, our novel strategy was applied, with sixteen patients with an onset greater than 6 h and eleven patients with an onset less than 6 h. During the waiting period, none died of aortic rupture, but four patients died of organ failure, twelve patients had organ function improvement and underwent surgery successfully survived. The overall mortality rate decreased with the use of this novel strategy (54.55% vs. 18.52%, p = 0.047). Furthermore, the surgical mortality rate between the two periods showed even stronger statistical significance (54.55% vs. 4.35%, p = 0.022). Moreover, the proportions of patients with sepsis and multiorgan failure also showed differences. CONCLUSIONS: Our novel strategy for patients with ATAAD complicated by mesenteric malperfusion not only improves the surgical success rate but also reduces the overall mortality rate.

Acute limb ischemia in nonagenarians: Characteristics and factors related to outcomes in a single-center consecutive series.

BACKGROUND: The increasing aging and frailty of the population make the management of acute limb ischemia (ALI) more difficult, with decision-making far from being guided by evidence. The aim of the study was to evaluate the characteristics and results of ALI treatment in nonagenarians. MATERIALS AND METHODS: Retrospective analysis of a consecutive series of nonagenarian patients with ALI attended at our institution between 2008 and 2021. The primary outcomes of the study were 1-year limb salvage and survival rates. RESULTS: A total of 102 patients were included (mean age 92.38, 78.4% women). In 83 cases (81.4%) ALI was attributed to embolism, and 19 (18.6%) to acute arterial thrombosis. One-month overall survival was 70.6%. Fifteen patients (14.7%) were treated palliatively, including 8 (53.3%) irreversible ALI with associated malignancy/advanced dementia, 5 (33.3%) with associated cerebral/intestinal ischemia and 2 (13.3%) with aortic occlusion and poor medical condition. None of these patients survived after 10 days. The remaining 87 patients (85.3%) were treated with isolated anticoagulation (n = 8, 9.1%), primary major amputation (n = 1, 1.1%) or revascularization (n = 78, 89.6%), including 69 (67.6%) embolectomies, 6 (5.9%) bypass and 3 (2.9%) endovascular techniques. One-year limb salvage and survival rates were 96% and 48%, respectively. Predictive factors of lower survival included anemia (HR = 1.81, p = 0.014) and ALI severity (HR = 1.73, p = 0.032), but not cognitive or functional status. Patients surviving the ALI episode had a 1-year survival rate significantly below that of a similar matched population. CONCLUSION: Although nonagenarians with an ALI are often functionally and cognitively impaired and have a limited life expectancy, most patients need revascularization for limb salvage and this can be done successfully with a low invasive surgery.

Association Between Diagnosis-to-Limb Revascularization Time and Clinical Outcomes in Outpatients With Chronic Limb-Threatening Ischemia: Insights From the CLIPPER Cohort.

BACKGROUND: The extent and consequences of ischemia in patients with chronic limb-threatening ischemia (CLTI) may change rapidly, and delays from diagnosis to revascularization may worsen outcomes. We sought to describe the association between time from diagnosis to endovascular lower extremity revascularization (diagnosis-to-limb revascularization [D2L] time) and clinical outcomes in outpatients with CLTI. METHODS AND RESULTS: In the CLIPPER cohort, comprising patients between 66 and 86 years old diagnosed with CLTI betweeen 2010 and 2019, we used Medicare claims data to identify patients who underwent outpatient endovascular revascularization within 180 days of diagnosis. We described the risk-adjusted association between D2L time and clinical outcomes. Among 1 130 065 patients aged between 66 and 86 years with CLTI, 99 221 (8.8%) underwent outpatient endovascular lower extremity revascularization within 180 days of their CLTI diagnosis. Among patients with D2L time <30 days, there was no association between D2L time and all-cause death or major lower extremity amputation. However, among patients with D2L time >30 days, each additional 10-day increase in D2L time was associated with a 2.5% greater risk of major amputation (hazard ratio, 1.025 [95% CI, 1.014-1.036]). There was no association between D2L time and all-cause death. CONCLUSIONS: A delay of >30 days from CLTI diagnosis to lower extremity endovascular revascularization was associated with an increased risk of major lower extremity amputation among patients undergoing outpatient endovascular revascularization. Improving systems of care to reduce D2L time could reduce amputations.

Identifying Factors Associated with Non-mesenterovascular Pathology in Patients Undergoing Surgical Treatment for Acute Mesenteric Ischemia.

AIM: To identify factors that can help us to avoid a preoperative incorrect diagnosis of vascular occlusion by evaluating patients who underwent laparotomy with a probable preoperative diagnosis of acute mesenteric ischemia (AMI), but later at laparotomy, were diagnosed to have a different pathology than AMI. MATERIAL AND METHODS: A total of 213 patients who were operated with the diagnosis of AMI were enrolled in this study. Based on their operational, clinical, and pathological findings, they were divided into two groups. Patient demographic data, along with the American Society of Anesthesiology (ASA) score, Charlson comorbidity index, history of previous abdominal surgery, and computed tomography (CT) findings were compared between groups. RESULTS: There were 37 patients in Group 1 (non-mesenterovascular pathology) and 176 patients in Group 2 (mesenterovascular pathology). The percentage of ASA 4 patients was higher in Group 2, with 48.3%, compared to 35.1% in Group 1 (p-value: 0.028). Upon admission, Group 2 had a higher rate of pathologic findings on CT examinations. 21.8% of the patients with non-mesenterovascular pathology had normal intra-abdominal findings. In univariate and multivariate analysis for no-nmesenterovascular pathology, patient age less than 65, Charlson comorbidity index 1-2, INR level >1.2, history of previous abdominal operation, and pneumatosis intestinalis were identified as independent risk factors. DISCUSSION: The possibility of non-mesenterovascular pathology in presumed AMI patients should be kept in mind, especially if the patients have a history of abdominal surgery, a low comorbidity index, an elevated international normalised ratio (INR), and are younger than 65 years of age. CONCLUSION: Evaluating the significant parameters identified in this study among patients with a preliminary diagnosis of AMI may prove useful in avoiding misdiagnosis and unnecessary surgeries.

Making decisions about amputation for chronic limb threatening ischaemia.

INTRODUCTION: Chronic limb threatening ischaemia causes pain, loss of function and complex wounds, necessitating urgent interventions. While growing options for minimally invasive revascularisation make operating on frail and older persons safer, the challenge is knowing when to stop this option and offer amputation. Decisions about amputation are difficult for the person, or for the family who act as substitute decision-makers. Timely treatment decisions are important to optimise clinical outcomes but do not always align with outcomes that are acceptable to patients. AIM: To provide a philosophically-based understanding of patient/family experiences of making decisions for chronic limb threatening ischaemia. METHODS: Longitudinal qualitative study using Heideggerian phenomenology. Patient and family participants were recruited from three sites. Semi-structured interviews occurred at two time points: soon after advice to consider major amputation, and for those who experienced amputation, six-months post-operatively. The COnsolidated criteria for REporting Qualitative studies (COREQ) checklist guided this report. FINDINGS: Variable timelines, disease progression, and interventions were encountered prior to confronting the possibility of amputation. Decision-making was interpreted as an initial irresoluteness (neglecting or renouncing decisions). For most, this was eventually followed by a resoluteness where participants either turned away or towards amputation, according to one's preferred mode of suffering, and thus owning the decision to turn. Those who opted for amputation often experienced better-than-anticipated outcomes. CONCLUSION: Patients and families had difficulty making decisions about amputation. Clinicians may have been complicit in the neglecting and renouncing of decisions and have an important role in sharing decision-making through their authentic discourse. IMPLICATIONS: Chronic limb threatening ischaemia requires complex discussions to support decisions and shared decision-making requires clinician presence and engagement in discourse. Patients and family members benefit from more time to experience and process the phenomenon as they move towards owning their decision about amputation.

Sex differences in outcomes after revascularization for acute lower limb ischemia: Propensity score adjusted analysis.

BACKGROUND: Previous reports have suggested higher rates of mortality and amputation for female patients in acute lower limb ischemia (ALI). The aims of the present study were to investigate if there is a difference in mortality, amputation, and fasciotomy between the sexes. METHODS: A retrospective cohort study of consecutive patients undergoing index revascularization for ALI between 2001 and 2018 was conducted. A propensity score was created through a logistic regression with female/male sex as an outcome. Cox regression analyses for 90-day and 1-year mortality, combining major amputation/mortality, and logistic regression for major bleeding and fasciotomy, were performed. All analyses were performed with and without adjusting for propensity score. RESULTS: A total of 709 patients were included in the study of which 45.9% were women. Mean age was 72.1 years. Females were older and had higher rates of atrial fibrillation, embolic disease, and lower estimated glomerular filtration rate, while men more often had anemia and chronic peripheral arterial disease. Mortality at 1 year was 21.2% for women and 14.7% for men. The adjusted hazard ratio for 1-year mortality was 0.99 (95% CI 0.67-1.46). Fasciotomy was performed in 7.1% of female and 12.8% of male patients; the adjusted odds ratio was 0.52 (95% CI 0.29-0.91). CONCLUSION: Sex was not found to be an independent risk factor for mortality or combined major amputation/mortality after revascularization for acute lower limb ischemia, whereas women had lower odds of undergoing fasciotomy. Whether women are underdiagnosed or do not develop acute compartment syndrome in the lower leg as often as men should be evaluated prospectively.

Aortobifemoral Bypass in Kidney Transplant Candidates: A Ten-Year Experience.

In patients with severe aorto-iliac calcifications, vascular reconstructions can be performed in order to allow kidney transplantation. The aim of this study was to analyze the outcomes of kidney transplant candidates who underwent an aortobifemoral bypass (ABFB) for aorto-iliac calcifications. A retrospective study including all kidney transplant candidates who underwent an ABFB between 2012 and 2022 was performed. Primary outcome was 30-day morbidity-mortality after ABFB. Secondary outcome was accessibility to kidney transplant waiting list. Twenty-two ABFBs were performed: 10 ABFBs in asymptomatic patients presenting severe aorto-iliac circumferential calcifications without hemodynamic consequences, and 12 ABFBs in symptomatic patients in whom aorto-iliac calcifications were responsible for claudication or critical limb threatening ischemia. Overall 30-day mortality was 0%. Overall 30-day morbidity was 22.7%: 1 femoral hematoma and 1 retroperitoneal hematoma requiring surgical drainage in the asymptomatic group, and 2 digestive ischemia requiring bowel resection and 1 femoral hematoma requiring surgical drainage in the symptomatic group. Among the 22 patients, 20 patients could access to kidney waiting list and 8 patients underwent a kidney transplantation, including 3 living-donor transplantations. Aorto-iliac revascularization can be an option to overcome severe calcifications contraindicating kidney transplantation.

Poor Limb Prognosis of Patients with Chronic Limb-Threatening Ischemia on Hemodialysis: A Retrospective Observational Study Based on the Global Limb Anatomic Staging System.

BACKGROUND: The Global Limb Anatomic Staging System (GLASS) has been widely used to evaluate patients with chronic limb-threatening ischemia (CLTI). As end-stage kidney disease (ESKD) is a well-known CLTI risk factor, we aimed to determine whether patients on hemodialysis (HD) have a worse limb prognosis than those without ESKD, considering the same GLASS background. METHODS: The data of 445 patients who underwent surgical and/or endovascular revascularization procedures for lower extremity ischemia were retrospectively collected in our division between 2005 and 2018. The major amputation rate and amputation-free survival (AFS) were compared between HD and non-HD patients. RESULTS: Among the 215 (48%) patients receiving HD, 58 limbs required major amputation (27% limb loss rate). Among the non-HD group, the limb loss rate was 13% (P < 0.0001). The overall AFS was significantly worse in patients receiving HD than those not (P < 0.0001). The AFS was significantly worse in HD patients when comparing GLASS-standardized subgroups. CONCLUSIONS: Patients with CLTI who were receiving HD had a worse limb prognosis than those not receiving, even when considering the same GLASS classification. Furthermore, there is a need for an ideal guideline focused on ESKD-directed peripheral artery disease.

Insulin Requirement and Infrainguinal Bypass Outcomes in Patients with Peripheral Arterial Disease.

BACKGROUND: Diabetes mellitus (DM) is a major risk factor for peripheral artery disease. The association of DM with major adverse limb events (MALE) after lower extremity revascularization remains controversial, as patients with diabetes are typically analyzed as a single, homogenous group. Using a large national database, this study examines the impact of insulin use and glycemic control on the outcomes following infrainguinal bypass. The hypothesis is that prevalent insulin therapy and elevated hemoglobin A1c (HbA1c) are associated with an increased risk of MALEs after infrainguinal bypass in patients with DM and could therefore be used for risk stratification. METHODS: The Vascular Quality Initiative database files for infrainguinal bypass (2007-2021) were retrospectively reviewed. Patients with DM undergoing bypass for peripheral artery disease were included. Patients on dialysis or with prior kidney transplantation were excluded. The characteristics and outcomes of patients with insulin-requiring diabetes mellitus (IRDM) were compared to those of patients not requiring insulin (noninsulin-requiring diabetes mellitus [NIRDM]) prior to the bypass procedure. RESULTS: A total of 9,686 patients with DM (56% IRDM) underwent bypass. Patients with IRDM were significantly younger than patients with NIRDM, more likely to be female (P < 0.01), African American (P < 0.01), and Hispanic (P = 0.031), and more likely to have comorbidities and be categorized into American Society of Anesthesiologist classes IV-V. They were more likely to be treated for chronic limb-threatening ischemia (P < 0.001). Patients with IRDM had significantly higher perioperative complications with no difference in perioperative mortality between the 2 groups. Beyond the perioperative period, with a mean follow-up of 427 days, patients with IRDM had significantly lower crude rates of primary patency and higher crude rates of major amputation, MALE, and mortality compared to patients with NIRDM. Regression analyses demonstrated that insulin requirement, but not HbA1c, was independently associated with a higher risk of MALE (hazard ratio = 1.17 [1.06-1.29]) and mortality (hazard ratio = 1.28 [1.16-1.43]). CONCLUSIONS: Insulin requirement, but not HbA1c, is significantly associated with MALEs and survival after infrainguinal bypass in the Vascular Quality Initiative. Stratification of patients with DM based on their prevalent insulin use prior to infrainguinal bypass surgery could improve the prediction of outcomes of peripheral arterial bypass surgery in patients with diabetes.