Illness Trajectories After Revascularization in Patients With Peripheral Artery Disease: A Unified Approach to Understanding the Risk of Major Amputation and Death.

BACKGROUND: The aim of this study was to investigate the illness trajectories of patients with peripheral artery disease (PAD) after revascularization and estimate the independent risks of major amputation and death (from any cause) and their interaction. METHODS: Data from Hospital Episode Statistics Admitted Patient Care were used to identify patients (≥50 years of age) who underwent lower limb revascularization for PAD in England from April 2013 to March 2020. A Markov illness-death model was developed to describe patterns of survival after the initial lower limb revascularization, if and when patients experienced major amputation, and survival after amputation. The model was also used to investigate the association between patient characteristics and these illness trajectories. We also analyzed the relative contribution of deaths after amputation to overall mortality and how the risk of mortality after amputation was related to the time from the index revascularization to amputation. RESULTS: The study analyzed 94 690 patients undergoing lower limb revascularization for PAD from 2013 to 2020. The majority were men (65.6%), and the median age was 72 years (interquartile range, 64-79). One-third (34.8%) of patients had nonelective revascularization, whereas others had elective procedures. For nonelective patients, the amputation rate was 15.2% (95% CI, 14.4-16.0) and 19.9% (19.0-20.8) at 1 and 5 years after revascularization, respectively. For elective patients, the corresponding amputation rate was 2.7% (95% CI, 2.4-3.1) and 5.3% (4.9-5.8). Overall, the risk of major amputation was higher among patients who were younger, had tissue loss, diabetes, greater frailty, nonelective revascularization, and more distal procedures. The mortality rate at 5 years after revascularization was 64.3% (95% CI, 63.2-65.5) for nonelective patients and 33.0% (32.0-34.1) for elective patients. After major amputation, patients were at an increased risk of mortality if they underwent major amputation within 6 months after the index revascularization. CONCLUSIONS: The illness-death model provides an integrated framework to understand patient outcomes after lower limb revascularization for PAD. Although mortality increased with age, the study highlights patients <60 years of age were at increased risk of major amputation, particularly after nonelective revascularization.

Plasma and tissue concentrations of 2 g prophylactic cefazolin prior to lower extremity surgery.

Surgical site infections (SSIs) are among the most clinically relevant complications and the use of prophylactic cefazolin is common practice. However, the knowledge about the pharmacological aspects of prophylactic cefazolin in the lower extremities remains limited. In this prospective cohort, a sub-study of the WIFI-2 randomized controlled trial, adults between 18 and 75 years of age who were scheduled for implant removal below the level of the knee and randomized for cefazolin, was included. A maximum of two venous plasma, target-site plasma, and target-site tissue samples were taken during surgery. The primary outcomes were the cefazolin concentrations in venous plasma, target-site plasma, and target-site tissue. A total of 27 patients [median (interquartile range) age, 42 (29-59) years; 17 (63%) male] with 138 samples were included in the study. A minimum of 6 weeks follow-up was available for all patients. The mean (SD) venous plasma, target-site plasma, and target-site tissue concentrations were 36 (13) µg/mL, 29 (13) µg/mL, and 28 (13) µg/g, respectively, and the cefazolin concentrations between the different locations of surgery did not differ significantly in both target-site plasma and target-site tissue (P = 0.822 and P = 0.840). In conclusion, 2 g of prophylactic cefazolin demonstrates adequacy in maintaining coverage for a duration of at least 80 minutes of surgery below the level of the knee, significantly surpassing the MIC90 required to combat the most prevalent microorganisms. This study represents the first of its kind to assess cefazolin concentrations in the lower extremities by examining both plasma and tissue samples in this magnitude.

Rate of Emergency Lower Extremity Amputations in the United States Among Medicare Beneficiaries.

OBJECTIVE: To determine the rate of emergency versus elective lower extremity amputations in the United States. BACKGROUND: Lower extremity amputation is a common endpoint for patients with poorly controlled diabetes and multilevel peripheral vascular disease. Although the procedure is ideally performed electively, patients with limited access may present later and require an emergency operation. To what extent rates of emergency amputation for lower extremities vary across the United States is unknown. METHODS: Evaluation of Medicare beneficiaries who underwent lower extremity amputation between 2015 and 2020. The rate was determined for each zip code and placed into rank order from lowest to highest rate. We merged each beneficiary's place of residence and location of care with the American Hospital Association Annual Survey using Google Maps Application Programming Interface to determine the travel distance for patients to undergo their procedure. RESULTS: Of 233,084 patients, 66.3% (154,597) were men, 69.8% (162,786) were White. The average age (SD) was 74 years (8). There was wide variation in rates of emergency lower extremity amputation. The lowest quintile of zip codes demonstrated an emergency amputation rate of 3.7%, whereas the highest quintile demonstrated 90%. The median travel distance in the lowest emergency surgery rate quintile was 34.6 miles compared with 10.5 miles in the highest quintile of emergency surgery ( P < 0.001). CONCLUSIONS: There is wide variation in the rate of emergency lower extremity amputations among Medicare beneficiaries, suggesting variable access to essential vascular care. Travel distance and rate of amputation have an inverse relationship, suggesting that barriers other than travel distance are playing a role.

Using Machine Learning (XGBoost) to Predict Outcomes After Infrainguinal Bypass for Peripheral Artery Disease.

OBJECTIVE: To develop machine learning (ML) algorithms that predict outcomes after infrainguinal bypass. BACKGROUND: Infrainguinal bypass for peripheral artery disease carries significant surgical risks; however, outcome prediction tools remain limited. METHODS: The Vascular Quality Initiative database was used to identify patients who underwent infrainguinal bypass for peripheral artery disease between 2003 and 2023. We identified 97 potential predictor variables from the index hospitalization [68 preoperative (demographic/clinical), 13 intraoperative (procedural), and 16 postoperative (in-hospital course/complications)]. The primary outcome was 1-year major adverse limb event (composite of surgical revision, thrombectomy/thrombolysis, or major amputation) or death. Our data were split into training (70%) and test (30%) sets. Using 10-fold cross-validation, we trained 6 ML models using preoperative features. The primary model evaluation metric was the area under the receiver operating characteristic curve (AUROC). The top-performing algorithm was further trained using intraoperative and postoperative features. Model robustness was evaluated using calibration plots and Brier scores. RESULTS: Overall, 59,784 patients underwent infrainguinal bypass, and 15,942 (26.7%) developed 1-year major adverse limb event/death. The best preoperative prediction model was XGBoost, achieving an AUROC (95% CI) of 0.94 (0.93-0.95). In comparison, logistic regression had an AUROC (95% CI) of 0.61 (0.59-0.63). Our XGBoost model maintained excellent performance at the intraoperative and postoperative stages, with AUROCs (95% CI's) of 0.94 (0.93-0.95) and 0.96 (0.95-0.97), respectively. Calibration plots showed good agreement between predicted and observed event probabilities with Brier scores of 0.08 (preoperative), 0.07 (intraoperative), and 0.05 (postoperative). CONCLUSIONS: ML models can accurately predict outcomes after infrainguinal bypass, outperforming logistic regression.

Clinical Impact of an Enhanced Recovery Program for Lower-extremity Bypass.

OBJECTIVE: To determine the association of Enhanced Recovery Program (ERP) implementation with length of stay (LOS) and perioperative outcomes after lower-extremity bypass (LEB). BACKGROUND: ERPs have been shown to decrease hospital LOS and improve perioperative outcomes, but their impact on patients undergoing vascular surgery remains unknown. METHODS: Patients undergoing LEB who received or did not receive care under the ERP were included; pre-ERP (January 1, 2016-May 13, 2018) and ERP (May 14, 2018-July 31, 2022). Clinicopathologic characteristics and perioperative outcomes were analyzed. RESULTS: Of 393 patients who underwent LEB [pre-ERP: n = 161 (41%); ERP: n = 232 (59%)], most were males (n = 254, 64.6%), White (n = 236, 60%), and government-insured (n = 265, 67.4%). Pre-ERP patients had higher Body Mass Index (28.8 ± 6.0 vs 27.4 ± 5.7, P = 0.03) and rates of diabetes (52% vs 36%, P = 0.002). ERP patients had a shorter total [6 (3-13) vs 7 (5-14) days, P = 0.01) and postoperative LOS [5 (3-8) vs 6 (4-8) days, P < 0.001]. Stratified by indication, postoperative LOS was shorter in ERP patients with claudication (3 vs 5 days, P = 0.01), rest pain (5 vs 6 days, P = 0.02), and tissue loss (6 vs 7 days, P = 0.03). ERP patients with rest pain also had a shorter total LOS (6 vs 7 days, P = 0.04) and lower 30-day readmission rates (32%-17%, P = 0.02). After ERP implementation, the average daily oral morphine equivalents decreased [median (interquartile range): 52.5 (26.6-105.0) vs 44.12 (22.2-74.4), P = 0.019], while the rates of direct discharge to home increased (83% vs 69%, P = 0.002). CONCLUSIONS: This is the largest single-center cohort study evaluating ERP in LEB, showing that ERP implementation is associated with shorter LOS and improved perioperative outcomes.

Effect of Lower Extremity Nerve Decompression in Patients With Painful Diabetic Peripheral Neuropathy: The Diabetic Neuropathy Nerve Decompression Randomized, Observation Group and Placebo Surgery-Controlled Clinical Trial.

OBJECTIVE: To evaluate the effect of nerve decompression on pain in patients with lower extremity painful diabetic peripheral neuropathy (DPN). BACKGROUND: Currently, no treatment provides lasting relief for patients with DPN. The benefits of nerve decompression remain inconclusive. METHODS: This double-blinded, observation and same-patient sham surgery-controlled randomized trial enrolled patients aged 18 to 80 years with lower extremity painful DPN who failed 1 year of medical treatment. Patients were randomized to nerve decompression or observation group (2:1). Decompression-group patients were further randomized and blinded to nerve decompression in either the right or left leg and sham surgery in the opposite leg. Pain (11-point Likert score) was compared between decompression and observation groups and between decompressed versus sham legs at 12 and 56 months. RESULTS: Of 2987 screened patients, 78 were randomized. At 12 months, compared with controls (n=37), both the right-decompression group (n=22) and left-decompression group (n=18) reported lower pain (mean difference for both: -4.46; 95% CI: -6.34 to -2.58 and -6.48 to -2.45, respectively; P < 0.0001). Decompressed and sham legs equally improved. At 56 months, compared with controls (n=m 14), pain was lower in both the right-decompression group (n=20; mean difference: -7.65; 95% CI: -9.87 to -5.44; P < 0.0001) and left-decompression group (n=16; mean difference: -7.26; 95% CI: -9.60 to -4.91; P < 0.0001). The mean pain score was lower in decompressed versus sham legs (mean difference: 1.57 95% CI: 0.46 to 2.67; P =0.0002). CONCLUSIONS: Although nerve decompression was associated with reduced pain, the benefit of surgical decompression needs further investigation as a placebo effect may be responsible for part or all of these effects.

Improved long-term functional outcomes and mortality of patients with vascular-related amputations utilizing the lower extremity amputation pathway.

BACKGROUND: Enhanced recovery after surgery pathways lead to improve perioperative outcomes for patients with vascular-related amputations; however, long-term data and functional outcomes are lacking. This study evaluated patients treated by the lower extremity amputation pathway (LEAP) and identified predictors of ambulation. METHODS: A retrospective review of LEAP patients who underwent major amputation from 2016 to 2022 for Wound, Ischemia, and foot Infection stage V disease was performed. LEAP patients were matched 1:1 with retrospective controls (NOLEAP) by hospital, need for guillotine amputation, and final amputation type (above knee vs below knee). The primary end point was the Medicare Functional Classification Level (K level) (functional classification of patients with amputations) at the last follow-up. RESULTS: We included 126 patients with vascular-related amputations (63 LEAP and 63 NOLEAP). Seventy-one percent of the patients were male and 49% were Hispanic with a mean state Area Deprivation Index of 9/10. There were no differences in baseline demographics or comorbidities. All patients had a K level of >0 (ambulatory) before amputation and an average Modified Frailty Index of 4. The median follow-up was 270 days (interquartile range, 84-1234 days) in the NOLEAP group and 369 days (interquartile range, 145-481 days) in the LEAP group. Compared with NOLEAP patients, LEAP patients were more likely to receive a prosthesis (86% vs 44%;P > .001). LEAP patients were more likely to have a K level of >0 (60% vs 25%; P = .003). On multivariable logistic regression, participation in LEAP increased the odds of a K level of >0 at follow-up by 5.8-fold (odds ratio, 5.8; 95% confidence interval, 2.5-13.6). Patients with a K level of >0 had significantly higher survival at 4 years (93% vs 59%; P = .001). In a Cox proportional hazards model, adjusted for demographics, comorbidities and amputation level, a K level of >0 at follow-up was associated with an 88% decrease in the risk of mortality compared with a K level of 0. CONCLUSIONS: LEAP leads to improved ambulation with a prosthesis in a socioeconomically disadvantaged and frail patient population. Patients with a K level of >0 (ambulatory) have significantly improved mortality.

Prosthetic outcomes after amputation and the impact of mobility level on survival.

OBJECTIVE: Lower extremity amputation continues to be necessary in a significant number of patients with peripheral vascular disease. The 5-year survival following lower limb loss is markedly reduced. Many of these patients are never fitted with a prosthesis, and there is a dearth of knowledge regarding the barriers to prosthetic attainment. The goal of this study was to identify the risk factors for not receiving a prosthesis and the effect of mobility level on survival following major amputation. METHODS: This was a retrospective analysis of all patients that underwent lower extremity amputation by surgeons in our practice from January 1, 2010, to December 31, 2019. Abstracted data included: age, sex, race, body mass index, comorbidities, American Society of Anesthesiologists score, statin use, level of amputation, stump revision, fitting for prosthesis, type of prosthesis, and the United States' Medicare Functional Classification Level, also called K level. Survival was determined using a combination of sources, including the Social Security Death Master File, searches of multiple genealogic registries, and general internet searches. Multivariable logistic regression was used to determine risk factors associated with prosthesis attainment. Multivariable Cox proportional hazard regression with time-dependent covariates was performed to assess risk factors associated with 5-year mortality. RESULTS: A total of 464 patients were included in this study. The mean age was 65 years, and mean body mass index was 27 kg/m2. The majority of patients were male (68%), White (56%), diabetic (62%), and hypertensive (76%), and underwent below-the-knee amputation (69%). Prosthetic attainment occurred in 185 (40%). On multivariable analysis, age >81 years and current tobacco use were associated with no prosthetic fitting. Overall 5-year survival was 41.9% (95% confidence interval [CI], 37.6%-46.6%) (below-the-knee amputation, 47.7% [95% CI, 42.5%-53.5%]; above-the-knee amputation, 28.7% [95% CI, 22.1%-37.2%]). On multivariable analysis, age >60 years, congestive heart failure, above-the-knee amputation, and no prosthetic attainment were associated with decreased survival. Increasing K level was incrementally associated with improved survival. CONCLUSIONS: This study has identified several patient factors associated with prosthetic attainment, as well as multiple factors predictive of reduced survival after amputation. Being referred for prosthetic fitting was associated with improved survival not explained by patient characteristics and comorbidities. The Medicare Functional Classification Level K level predicts survival. More research is needed to determine the barriers to prosthetic attainment and if improving a patients K level will improve survival.

Systemic immunosuppression does not affect revascularization outcomes in patients with chronic limb-threatening ischemia.

OBJECTIVE: Many patients with chronic limb-threatening ischemia (CLTI) have additional comorbidities requiring systemic immunosuppression. Few studies have analyzed whether these medications may inhibit graft integration and effectiveness, or conversely, whether they may prevent inflammation and/or restenosis. Therefore, our study aim was to examine the effect of systemic immunosuppression vs no immunosuppression on outcomes after any first-time lower extremity revascularization for CLTI. METHODS: We identified all patients undergoing first-time infrainguinal bypass graft (BPG) or percutaneous transluminal angioplasty with or without stenting (PTA/S) for CLTI at our institution between 2005 and 2014. Patients were stratified by procedure type and immunosuppression status, defined as ≥6 weeks of any systemic immunosuppression therapy ongoing at the time of intervention. Immunosuppression vs nonimmunosuppression were the primary comparison groups in our analyses. Primary outcomes included perioperative complications, reintervention, primary patency, and limb salvage, with Kaplan-Meier and Cox proportional hazard models used for univariate and multivariate analyses, respectively. RESULTS: Among 1312 patients, 667 (51%) underwent BPG and 651 (49%) underwent PTA/S, of whom 65 (10%) and 95 (15%) were on systemic immunosuppression therapy, respectively. Whether assessing BPG or PTA/S patients, there were no differences noted in perioperative outcomes, including perioperative mortality, myocardial infarction, stroke, hematoma, or surgical site infection (P > .05). For BPG patients, Kaplan-Meier analysis and log-rank testing demonstrated no significant difference in three-year reintervention (37% vs 33% [control]; P = .75), major amputation (27% vs 15%; P = .64), or primary patency (72% vs 66%; P = .35) rates. Multivariate analysis via Cox regression confirmed these findings (immunosuppression hazard ratio [HR] for reintervention, 0.95; 95% CI, 0.56-1.60; P = .85; for major amputation, HR, 1.44; 95% CI, 0.70-2.96; P = .32; and for primary patency. HR, 0.97; 95% CI, 0.69-1.38; P = .88). For PTA/S patients, univariate analysis revealed similar rates of reintervention (37% vs 39% [control]; P = .57) and primary patency (59% vs 63%; P = .21); however, immunosuppressed patients had higher rates of major amputation (23% vs 12%; P = .01). After using Cox regression to adjust for baseline demographics, as well as operative and anatomic characteristics, immunosuppression was not associated with any differences in reintervention (HR, 0.75; 95% CI, 0.49-1.16; P = .20), major amputation (HR, 1.46; 95% CI, 0.81-2.62; P = .20), or primary patency (HR, 0.84; 95% CI, 0.59-1.19; P = .32). Sensitivity analyses for the differences in makeup of immunosuppression regimens (steroids vs other classes) did not alter the interpretation of any findings in either BPG or PTA/S cohorts. CONCLUSIONS: Our findings demonstrate that patients with chronic systemic immunosuppression, as compared with those who are not immunosuppressed, does not have a significant effect on late outcomes after lower extremity revascularization, as measured by primary patency, reintervention, or major amputation.

Prosthetic fitting and mortality after major lower extremity amputation.

BACKGROUND: Studies suggest that ambulation after major lower extremity amputation (LEA) is low and mortality after LEA is high. Successful prosthetic fitting after LEA has a significant quality of life benefit; however, it is unclear if there are benefits in post-LEA mortality. Our objective was to examine a contemporary cohort of patients who underwent LEA and determine if there is an association between fitting for a prosthetic and mortality. METHODS: We reviewed all patients who underwent LEA between 2015 and 2022 at two academic health care systems in a large metropolitan city. The exposure of interest was prosthetic fitting after LEA. The primary outcomes were mortality within 1 and 3 years of follow-up. Ambulation after LEA was defined as being ambulatory with or without an assistive device. Patients with prior LEA were excluded. Extended Cox models with time-dependent exposure were used to evaluate the association between prosthetic fitting and mortality at 1 and 3 years of follow-up. RESULTS: Among 702 patients who underwent LEA, the mean (SD) age was 64.3 (12.6) years and 329 (46.6%) were fitted for prosthetic. The study population was mostly male (n = 488, 69.5%), predominantly non-Hispanic Black (n = 410, 58.4%), and nearly one-fifth were non-ambulatory before LEA (n = 139 [19.8%]). Of note, 14.3% of all subjects who were nonambulatory at some point after LEA, and 28.5% of patients not ambulatory preoperatively were eventually ambulatory after LEA. The rate of death among those fitted for a prosthetic was 12.0/100 person-years at 1 year and 5.8/100 person-years at 3 years of follow-up; among those not fitted for a prosthetic, the rate of death was 55.7/100 person-years and 50.7/100 person-years at 1 and 3 years of follow-up, respectively. After adjusting for several sociodemographic data points, comorbidities, pre- or post- coronavirus disease 2019 pandemic timeframe, and procedural factors, prosthetic fitting is associated with decreased likelihood of mortality within 1 year of follow-up (adjusted hazard ratio, 0.24; 95% confidence interval, 0.14-0.40) as well as within 3 years (adjusted hazard ratio, 0.40; 95% confidence interval, 0.29-0.55). CONCLUSIONS: Prosthetic fitting is associated with improved survival, and preoperative functional status does not always predict postoperative functional status. Characterizing patient, surgical, and rehabilitation factors associated with receipt of prosthetic after LEA may improve long-term survival in these patients. Process measures employed by the Department of Veterans Affairs, such as prosthetic department evaluation of all amputees, may represent a best practice.

Implementation of a vascular acute care surgery model is associated with improved surgeon efficiency and 2-year mortality after lower extremity intervention.

OBJECTIVE: Vascular surgeons work long, unpredictable hours with repeated exposure to high-stress situations. Inspired by general surgery acute care surgery models, we sought to organize the care of vascular emergencies with the implementation of a vascular acute care surgery (VACS) model. Within this model, a surgeon is in-house without elective cases and assigned for consultations and urgent operative cases on a weekly basis. This study examined the impact of a VACS model on postoperative mortality and surgeon efficiency. METHODS: This was a retrospective cohort analysis of institutional Vascular Quality Initiative data from July 2014 to July 2023. Patients undergoing lower extremity bypass, peripheral vascular intervention, or amputation were included. There was a washout period from January 2020 to January 2022 to account for COVID-19 pandemic practice abnormalities. Patients were separated into pre- or post-VACS groups. The primary clinical outcomes were 30-day and 2-year mortality. Secondary clinical outcomes included 30-day complications and 30-day and 1-year major adverse limb events (MALE). Separate analyses of operating room data from July 2017 to February 2024 and fiscal data from fiscal year 2019 to fiscal year 2024 were conducted. A washout period from January 2020 to January 2022 was applied. Efficiency outcomes included monthly relative value units (RVUs) per clinical fraction full-time equivalent (cFTE) and daytime (0730-1700, Monday-Friday) operating room minutes. Patient factors and operative efficiency were compared using appropriate statistical tests. Regression modeling was performed for the primary outcomes. RESULTS: There were 972 and 257 patients in the pre- and post-VACS groups, respectively. Pre-VACS patients were younger (66.8 ± 12.0 vs 68.7 ± 12.7 years; P = .03) with higher rates of coronary artery disease (34.6% vs 14.8%; P < .01), hypertension (88.4% vs 82.2%; P = .01), and tobacco history (84.4% vs 78.2%; P = .02). Thirty-day mortality (2.4% pre-vs 0.8% post-VACS; P = .18) and Kaplan-Meier estimation of 2-year mortality remained stable after VACS (P = .07). VACS implementation was not associated with 30-day mortality but was associated with lower 2-year mortality hazard on multivariable Cox regression (hazard ratio [HR], 0.5; 95% confidence interval [CI], 0.3-0.9; P = .01). Operative efficiency improved post-VACS (median, 850.0; interquartile range [IQR], 765.7-916.3 vs median, 918.0; IQR, 881.0-951.1 RVU/cFTE-month; P = .03). Daytime operating minutes increased (469.1 ± 287.5 vs 908.2 ± 386.2 minutes; P < .01), whereas non-daytime minutes (420.0; IQR, 266.0-654.0 vs 469.5; IQR, 242.0-738.3 minutes; P = .40) and weekend minutes (129.0; IQR, 0.0-298.0 vs 113.5; IQR, 0.0-279.5 minutes; P = .59) remained stable. CONCLUSIONS: A VACS model leads to improvement in surgeon operative efficiency while maintaining patient safety. The adoption of a vascular acute care model has a positive impact on the delivery of comprehensive vascular care.

Long-term outcomes of autologous vein bypass for repair of upper and lower extremity major arterial trauma.

OBJECTIVE: Autologous vein is the preferred bypass conduit for extremity arterial injuries owing to superior patency and low infection risk; however, long-term data on outcomes in civilians are limited. Our goal was to assess short- and long-term outcomes of autologous vein bypass for upper and lower extremity arterial trauma. METHODS: A retrospective review was performed of patients with major extremity arterial injuries (2001-2019) at a level I trauma center. Demographics, injury and intervention details, and outcomes were recorded. Primary outcomes were primary patency at 1 year and 3 years. Secondary outcomes were limb function at 6 months, major amputation, and mortality. Multivariable analysis determined risk factors for functional impairment. RESULTS: There were 107 extremity arterial injuries (31.8% upper and 68.2% lower) treated with autologous vein bypass. Mechanism was penetrating in 77% of cases, of which 79.3% were due to firearms. The most frequently injured vessels were the common and superficial femoral (38%), popliteal (30%), and brachial arteries (29%). For upper extremity trauma, concomitant nerve and orthopedic injuries were found in 15 (44.1%) and 11 (32.4%) cases, respectively. For lower extremities, concomitant nerve injuries were found in 10 (13.7%) cases, and orthopedic injuries in 31 (42.5%). Great saphenous vein was the conduit in 96% of cases. Immediate intraoperative bypass revision occurred in 9.3% of patients, most commonly for graft thrombosis. The in-hospital return to operating room rate was 15.9%, with graft thrombosis (47.1%) and wound infections (23.5%) being the most common reasons. The median follow-up was 3.6 years. Kaplan-Meier analysis showed 92% primary patency at 1 year and 90% at 3 years. At 6 months, 36.1% of patients had functional impairment. Of patients with functional impairment at 6 months, 62.9% had concomitant nerve and 60% concomitant orthopedic injuries. Of those with nerve injury, 91.7% had functional impairment, compared with 17.8% without nerve injury (P < .001). Of patients with orthopedic injuries, 51.2% had functional impairment, vs 25% of those without orthopedic injuries (P = .01). On multivariable analysis, concomitant nerve injury (odds ratio, 127.4; 95% confidence interval, 17-957; P <. 001) and immediate intraoperative revision (odds ratio, 11.03; 95% confidence interval, 1.27-95.55; P = .029) were associated with functional impairment. CONCLUSIONS: Autologous vein bypass for major extremity arterial trauma is durable; however, many patients have long-term limb dysfunction associated with concomitant nerve injury and immediate intraoperative bypass revision. These factors may allow clinicians to identify patients at higher risk for functional impairment, to outline patient expectations and direct rehabilitation efforts toward improving functional outcomes.

The importance of optimal medical therapy in patients undergoing lower extremity bypass.

PURPOSE OF REVIEW: The prevalence of peripheral artery disease is growing, with millions of people globally suffering its end-stage manifestation, chronic limb-threatening ischemia (CLTI). Revascularization procedures like lower extremity bypass play a vital role in limb salvage but optimal medical therapy is essential for maximizing the benefit of these procedures and reducing long-term risks of cardiovascular and limb-related events. RECENT FINDINGS: Patients with PAD who undergo lower extremity bypass warrant a comprehensive approach to risk factor modification for both primary and secondary prevention of cardiovascular and limb-related complications. This includes appropriate use of high-intensity statins, smoking cessation, and management of hypertension and diabetes. Additionally, antiplatelet therapy is indicated for all patients with CLTI and additional treatment with low-dose anticoagulation may also be beneficial. SUMMARY: Optimal medical therapy is essential for optimizing outcomes in patients with PAD undergoing lower extremity bypass.

Validity of the Musculoskeletal Tumor Society Score for lower extremity in patients with bone sarcoma or giant cell tumour of bone undergoing bone resection and reconstruction surgery in hip and knee.

BACKGROUND: The Musculoskeletal Tumor Society Score (MSTS) is widely used to evaluate functioning following surgery for bone and soft-tissue sarcoma. However, concerns have been raised about its content validity due to the lack of patient involvement during item development. Additionally, literature reports inconsistent results regarding data quality and structural validity. This study aimed to evaluate content, structural and construct validity of the Danish version of the MSTS for lower extremity (MSTS-LE). METHODS: The study included patients from three complete cohorts (n = 87) with bone sarcoma or giant cell tumour of bone who underwent bone resection and reconstruction surgery in hip and knee. Content validity was evaluated by linking MSTS items to frameworks of functioning, core outcome sets and semi-structured interviews. Data quality, internal consistency and factor analysis were used to assess the underlying structure of the MSTS. Construct validity was based on predefined hypotheses of correlation between the MSTS and concurrent measurements. RESULTS: Content validity analysis revealed concerns regarding the MSTS. The MSTS did not sufficiently cover patient-important functions, the item Emotional acceptance could not be linked to the framework of functioning, the items Pain and Emotional acceptance pertained to domains beyond functioning and items' response options did not match items. A two-factor solution emerged, with the items Pain and Emotional acceptance loading highly on a second factor distinct from functioning. Internal consistency and construct validity showed values below accepted levels. CONCLUSION: The Danish MSTS-LE demonstrated inadequate content validity, internal consistency, and construct validity. In addition, our analyses did not support unidimensionality of the MSTS. Consequently, the MSTS-LE is not a simple reflection of the construct of functioning and the interpretation of a sum score is problematic. Clinicians and researcher should exercise caution when relying solely on MSTS scores for assessing lower extremity function. Alternative outcome measurements of functioning should be considered for the evaluation of postoperative function in this patient group.

The impact of diabetes on mortality rates after lower extremity amputation.

OBJECTIVE: To assess the impact of diabetes, amputation level, sex and age on mortality rates after lower extremity amputation (LEA) in Belgium, and to assess temporal trends in one-year survival rates from 2009 to 2018. METHODS: Nationwide data on individuals who underwent minor and major LEA from 2009 to 2018 were collected. Kaplan-Meier survival curves were constructed. A Cox regression model with time-varying coefficients was used to estimate the likelihood of mortality after LEA in individuals with or without diabetes. Matched amputation-free individuals with or without diabetes were used for comparison. Time trends were analysed. RESULTS: Amputations 41,304 were performed: 13,247 major and 28,057 minor. Five-year mortality rates in individuals with diabetes were 52% and 69% after minor and major LEA, respectively (individuals without diabetes: 45% and 63%, respectively). In the first six postoperative months, no differences in mortality rates were found between individuals with or without diabetes. Later, hazard ratios (HRs) for mortality in individuals with diabetes (compared with no diabetes) after minor LEA ranged from 1.38 to 1.52, and after major LEA from 1.35 to 1.46 (all p ≤ 0.005). Among individuals without LEA, HRs for mortality in diabetes (versus no diabetes) were systematically higher compared to the HRs for mortality in diabetes (versus no diabetes) after minor and major LEA. One-year survival rates did not change for individuals with diabetes. CONCLUSIONS: In the first six postoperative months, mortality rates after LEA were not different between individuals with or without diabetes; later, diabetes was significantly associated with increased mortality. However, as HRs for mortality were higher in amputation-free individuals, diabetes impacts mortality less in the minor and major amputation groups relative to the comparison group of individuals without LEA.

A tool to predict the risk of lower extremity amputation in patients starting dialysis.

BACKGROUND: Non-traumatic lower extremity amputation (LEA) is a severe complication during dialysis. To inform decision-making for physicians, we developed a multivariable prediction model for LEA after starting dialysis. METHODS: Data from the Swedish Renal Registry (SNR) between 2010 and 2020 were geographically split into a development and validation cohort. Data from Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD) between 1997 and 2009 were used for validation targeted at Dutch patients. Inclusion criteria were no previous LEA and kidney transplant and age ≥40 years at baseline. A Fine-Gray model was developed with LEA within 3 years after starting dialysis as the outcome of interest. Death and kidney transplant were treated as competing events. One coefficient, ordered by expected relevance, per 20 events was estimated. Performance was assessed with calibration and discrimination. RESULTS: SNR was split into an urban development cohort with 4771 individuals experiencing 201 (4.8%) events and a rural validation cohort with 4.876 individuals experiencing 155 (3.2%) events. NECOSAD contained 1658 individuals experiencing 61 (3.7%) events. Ten predictors were included: female sex, age, diabetes mellitus, peripheral artery disease, cardiovascular disease, congestive heart failure, obesity, albumin, haemoglobin and diabetic retinopathy. In SNR, calibration intercept and slope were -0.003 and 0.912, respectively. The C-index was estimated as 0.813 (0.783-0.843). In NECOSAD, calibration intercept and slope were 0.001 and 1.142 respectively. The C-index was estimated as 0.760 (0.697-0.824). Calibration plots showed good calibration. CONCLUSION: A newly developed model to predict LEA after starting dialysis showed good discriminatory performance and calibration. By identifying high-risk individuals this model could help select patients for preventive measures.

A prospective observational study to evaluate a possible relationship between vitamin K antagonist therapy and risk of peripheral arterial disease in patients with type 2 diabetes.

AIM: The use of vitamin K antagonists (VKAs) may increase the risk of peripheral arterial disease (PAD) because vitamin K is a strong inhibitor of medial arterial calcification. Type 2 diabetes (T2D) exposes patients to an increased risk of PAD. We examined how the use of VKAs modulates the risk of incident PAD in people with T2D. MATERIALS AND METHODS: SURDIAGENE is a French cohort including 1468 patients with T2D with a prospective follow-up from 2002 to 2015. The primary outcome of the current analysis was the first occurrence of PAD, a composite of lower-limb amputation (LLA) or lower-limb revascularization. LLA and lower-limb revascularization were considered individually as secondary outcomes. RESULTS: During a 7-year median follow-up, PAD occurred in 147 (10%) of the 1468 participants. The use of VKAs was not significantly associated with the risk of PAD [multivariable adjusted hazard ratio (HR) 1.42, 95% confidence interval (CI), 0.88-2.31]. During the study period, LLA and lower-limb revascularization occurred in 82 (6%) and 105 (7%) participants, respectively. The use of VKAs was significantly associated with increased risk of LLA [multivariable adjusted HR 1.90 (95% CI, 1.04-3.47)], but not lower-limb revascularization [multivariable adjusted HR 1.08 (95% CI, 0.59-1.97)]. CONCLUSIONS: In this prospective study, we did not observe any excess risk of PAD requiring lower-limb revascularization in people with type 2 diabetes using VKAs. However, our data suggest a high risk of LLA in VKA users. Further studies are required to confirm this observation.

Predictive Modeling for One-Year Lower Extremity Endovascular Revascularization Failure in Black Persons.

INTRODUCTION: Black persons bear a disproportionate burden of peripheral artery disease (PAD) and experience higher rates of endovascular revascularization failure (ERF) when compared with non-Hispanic White persons. We aimed to identify predictors of ERF in Black persons using predictive modeling. METHODS: This retrospective study included all persons identifying as Black who underwent an initial endovascular revascularization procedure for PAD between 2011 and 2018 at a midwestern tertiary care center. Three predictive models were developed using (1) logistic regression, (2) penalized logistic regression (least absolute shrinkage and selection operator [LASSO]), and (3) random forest (RF). Predictive performance was evaluated under repeated cross-validation. RESULTS: Of the 163 individuals included in the study, 113 (63.1%) experienced ERF at 1 y. Those with ERF had significant differences in symptom status (P < 0.001), lesion location (P < 0.001), diabetes status (P = 0.037), and annual procedural volume of the attending surgeon (P < 0.001). Logistic regression and LASSO models identified tissue loss, smoking, femoro-popliteal lesion location, and diabetes control as risk factors for ERF. The RF model identified annual procedural volume, age, PAD symptoms, number of comorbidities, and lesion location as most predictive variables. LASSO and RF models were more sensitive than logistic regression but less specific, although all three methods had an overall accuracy of ≥75%. CONCLUSIONS: Black persons undergoing endovascular revascularization for PAD are at high risk of ERF, necessitating need for targeted intervention. Predictive models may be clinically useful for identifying high-risk patients, although individual predictors of ERF varied by model. Further exploration into these models may improve limb salvage for this population.

Development of an Education Material Targeting Patients Undergoing Lower Extremity Amputation due to Severe Limb Ischemia-A Qualitative Study.

INTRODUCTION: Critical limb-threatening ischemia (CLTI) is associated with a high risk of amputation, yet patients undergoing amputation due to CLTI have little knowledge of the amputation process and the rehabilitation that awaits. The aim of the present study was to develop and validate information material for patients undergoing amputation. METHODS: Nine participants were included in the study. Two focus group interviews were performed with seven patients who had undergone lower extremity amputation due to CLTI within the past 2 y. Additionally, two individual interviews were carried out. A semistructured interview guide was used, and the interviews were transcribed verbatim and analysed using qualitative content analysis with a deductive approach. RESULTS: Three themes were identified as essential for the design of the written information: Perspectives on design and formatting, Providing information to enhance participation in care, and Accessibility to information and support. The prototyped information leaflet was perceived as acceptable, useable, relevant, and comprehensible by the participants. CONCLUSIONS: For patients to actively engage in their care, it is vital that their information needs are met and that they are provided with psychosocial support when needed. Written and oral information should be provided by a trusted healthcare professional.

Factors Associated With Major Lower Extremity Amputations in Diabetic Foot Infections at a County Hospital in Guatemala.

INTRODUCTION: Outcomes from diabetic foot infections (DFIs) at the major referral hospital (Hospital Nacional de San Benito) in El Petén, Guatemala have not been analyzed. We hypothesized that poor diabetic control might be associated with a high rate of major lower extremity amputations (mLEAs; above the ankle). METHODS: We performed a retrospective analysis at Hospital Nacional de San Benito between (8/14 and 6/23) in patients presenting with DFIs. Patients receiving mLEAs were compared with all others (AO = [trans-metatarsal amputations, toe amputations, incision and drainage, and antibiotic treatment]). Interviews surgeons were undertaken to ascertain reasons for index operation choice. Univariable and multivariable analyses were undertaken to determine factors associated with mLEAs. RESULTS: Of 110 patients with DFIs, there were 23 mLEAs (above the knee = 21, below the knee = 2). Age, duration with diabetes, and a prior ipsilateral minor amputation were associated with mLEAs. Multivariable analysis identified white blood cell count as significant for mLEA (odds ratio = 1.5 95% confidence interval [1.0 to 2.5]). Cited reasons for a high rate of above the knee amputation (AKAs) versus below the knee amputation were patient related (advanced disease, patient frailty, and poor compliance), systemic (lack of vascular equipment and knee immobilizer), and surgeon related. CONCLUSIONS: This cohort of patients presented with an average of 15 years with diabetes mellitus and poor adherence to diabetic treatment (40%). Many of these diabetic patients developed a DFI requiring mLEAs (21%), most of which were AKAs (91%). Efforts to minimize the number of AKA versus below the knee amputation require immediate attention. Programs to adhere to DM control and foot care in patients with DM are urgently needed.