Preoperative Nil Per Os Duration Predicts Mortality and Ambulation Following Below-Knee Amputation.

BACKGROUND: Routine use of nil per os (NPO) prior to procedures has been associated with dehydration and malnutrition leading to patient discomfort. We aim to examine how duration of NPO status affects postoperative outcomes in patients undergoing elective below-knee amputation (BKA). METHODS: We performed a retrospective chart review of 92 patients who underwent elective BKA between 2014-2022 for noninfectious indications. We performed statistical analysis using Chi-square tests, t-tests, and linear/logistic regression with odds ratio using P < .05 as our significance level. RESULTS: The mean age was 48.0 ± 16.7 years, and there were 64 (70%) male patients and 41 (45%) Black patients. Mean NPO duration was 12.9 ± 4.7 hours. Patients with longer NPO duration were associated with increased rates of postoperative stroke (P = .03). Patients with shorter NPO duration had significantly lower mean BUN on postoperative day (POD) 1 (14.5, P < .001) and POD 3 (14.1, P < .001) compared to preoperative mean BUN (16.8), however this normalized by POD 7 (19.2, P = .26). There were no changes in postoperative renal function based on baseline kidney disease status or associated with longer NPO duration. Shorter NPO duration was a predictor of increased likelihood of 1-year follow-up (OR: 2.9 [1.24-6.79], P = .01), independent ambulation (OR: 2.7 [1.03-7.34], P = .04), and decreased mortality (OR: .11 [.013-.91], P = .04). CONCLUSION: While NPO duration does not appear to result in postoperative renal dysfunction, prolonged NPO duration predicts worse rates of follow-up, ambulation, and survival and is associated with increased stroke rates.

MODERATE AND SEVERE CHRONIC KIDNEY DISEASE PREDICT GREATER 5-YEAR MORTALITY FOLLOWING MAJOR LOWER EXTREMITY AMPUTATION.

INTRODUCTION: Severe Chronic Kidney Disease (CKD) predicts greater mortality after major lower extremity amputation (LEA), but it remains poorly understood whether patients with earlier stages of CKD share similar risk. METHODS: We assessed long-term postoperative outcomes for patients with CKD in a retrospective chart review of 565 patients who underwent atraumatic major LEA at a large tertiary referral center from 2015 to 2021. We stratified patients by renal function and compared outcomes including survival. RESULTS: Preoperative CKD diagnosis was related to many patient characteristics, co-occurred with many comorbidities, and was associated with less follow-up and survival. Kaplan-Meier and Cox Regression analyses showed significantly worse 5-year survival for major LEA patients with mild, moderate, or severe CKD compared to major LEA patients with no history of CKD at the time of amputation (P < 0.001). Severe CKD independently predicted worse mortality at 1-year (odds ratio [OR] 2.91; P = 0.003) and 5-years (OR 3.08; P < 0.001). Moderate CKD independently predicted worse 5-year mortality (OR 2.66; P = 0.029). CONCLUSION: This study demonstrates that moderate and severe CKD predict greater long-term mortality following major LEA when controlling for numerous potential confounders. This finding raises questions about the underlying mechanism if causal and highlights an opportunity to improve outcomes with earlier recognition and optimization CKD preoperatively.

Totally percutaneous endovascular renal allograft salvage for common iliac artery pseudoaneurysm.

Delayed presentation of recipient artery pseudoaneurysms following kidney transplantation is a rare, yet critical, complication. Although the precise etiology remains unclear, factors such as chronic steroid use, iatrogenic injuries (including vascular clamp damage during index surgery), or infections could contribute. Timely surgical intervention is imperative to prevent arterial rupture and life-threatening bleeding. Open repair, although commonly used, is associated with notable mortality rates and graft loss. Endovascular repair for delayed presentations of native iliac artery pseudoaneurysms has seen limited documentation in the literature. We present a case involving salvage of a kidney graft through innovative application of an endovascular technique using a modified stent graft with fenestration for the transplanted renal artery. The pseudoaneurysm, discovered 4 years after transplantation, was situated in proximity to the anastomosis site of the kidney graft's renal artery to recipient common iliac artery. Traditional open repair posed significant risks of graft loss due to its location near the kidney allograft. Our approach successfully resolved the issue, preserving graft function and resulting in a short length of hospital stay. This case contributes to the limited body of knowledge on delayed presentation of pseudoaneurysms after kidney transplantation. Successful application of an endovascular approach underscores its potential as a safe and effective alternative to open repair, offering favorable outcomes in terms of patient morbidity, mortality, and graft salvage.

Delayed Closure of Guillotine Lower Extremity Amputation in Obese Patients is Associated with Increased Mortality.

BACKGROUND: Staged surgery with open guillotine amputation (OGA) prior to a definitive major lower extremity amputation (LEA) has been shown to be effective for sepsis control and improving wound healing. Studies have evaluated postoperative complications including infection, return to the operating room for re-amputation, and amputation failure following OGA. However, the role of timing to close OGA for predictive outcomes remains poorly understood. We aim to assess outcomes of major LEA related to the time of OGA closure. METHODS: Data from patients who underwent major LEA from 2015 to 2021 were collected retrospectively. The study included all patients undergoing below-knee, through-knee, or above-knee amputations. Next, patients who had OGA prior to a definitive amputation were selected. Patients who died before amputation closure were excluded. Postamputation outcomes such as surgical site infection, postoperative sepsis, postoperative ambulation, hospital length of stay, and 30-day, 1-year, and 5-year mortality were reviewed. The study cohort was stratified by demographics and comorbidities. Receiver operating characteristic curve analysis was performed to determine the time of closure (TOC) cutoff value. Univariate and multivariate analysis was performed to assess outcomes. Statistical significance was set at P < 0.05. RESULTS: Of 688 patients who underwent major LEA, 322 underwent staged amputation with OGA before the formalization procedure and were included. The TOC ranged from 1-47 days with a median of 4 days (interquartile range from 3 to 7). The optimal TOC point of 8 days (ranging from 2-42 days) in obese patients (199/322) for predicting mortality showed the largest area under the curve (0.709) with 64.71% sensitivity and 78.3% specificity. Patients who are obese and grouped in TOC less than 8 days had no 30-day mortality, significantly lower 1-year mortality, better survival, and a lower rate of deep venous thrombosis complication. There was no significant difference in length of stay, postoperative surgical site infection, sepsis, and ambulation between the 2 subgroups of obese patients. Multivariable analysis showed that gender, chronic kidney disease, and postoperative ambulation independently predict overall mortality in obese patients. CONCLUSIONS: TOC cutoff in obese patients showed statistically significant results in predicting mortality. Our findings indicated better survival in obese patients with a lower TOC (less than 8 days). This emphasizes the importance of earlier closure of OGA in obese patients.

Risk Factors for Lower Extremity Minor Amputation Conversion to Major Amputation.

BACKGROUND: Minor lower extremity amputations (LEAs) have become an important part of the limb salvage approach but are not as benign as previously thought. This study investigates the difference in outcome between toe/ray versus midfoot amputations and the risk factors for major amputation conversion associated with each procedure. METHODS: We performed retrospective chart review of foot amputation patients at a single tertiary care medical center with a primary end point of conversion to major amputation and secondary end points of 1-year wound healing and mortality rate. We collected data on relevant medical comorbidities, noninvasive vascular imaging, revascularization, repeat amputations, wound healing rate, and 1-year mortality. Patients were separated into toe/ray amputations versus midfoot amputation groups and compared using descriptive statistics, Chi-squared tests, Cox proportional hazards, and a multivariate logistic regression model. RESULTS: A total of 375 amputations were included in the analysis. 65.3% (245 patients) included toe/ray amputations and 34.7% (130 patients) included midfoot amputations. We compared these 2 cohorts with regard to their rate of conversion to repeat minor and/or major amputation in addition to overall mortality. The toe/ray group underwent more repeat minor amputations within 1 year after index amputation (34.7% vs. 21.5%, P = 0.008) and wound healing (epithelization) at 90 days was also higher in this group. The midfoot group had a higher conversion to major LEA within 1 year on univariate analysis (20.8 vs. 6.9%, P < 0.001). Overall 1-year mortality was 6.17% and there was no significant difference between groups. CONCLUSIONS: While there is a consistency with previous studies that found no significant overall difference in mortality between types of minor LEA, we have extended this previous work by demonstrating the independent risk factors for conversion to major amputation between types of minor LEA. Comparing these 2 groups will assist surgeons in choosing the appropriate level of amputations and will enhance patient's understanding of their chance of wound healing and risk of repeat amputation.

Risk factors and treatment interventions associated with incomplete thrombus resolution and pulmonary hypertension after pulmonary embolism.

BACKGROUND: Residual pulmonary vascular occlusion (RPVO) affects one half of patients after a pulmonary embolism (PE). The relationship between the risk factors and therapeutic interventions for the development of RPVO and chronic thromboembolic pulmonary hypertension is unknown. METHODS: This retrospective review included PE patients within a 26-month period who had baseline and follow-up imaging studies (ie, computed tomography [CT], ventilation/perfusion scans, transthoracic echocardiography) available. We collected the incidence of RPVO, percentage of pulmonary artery occlusion (%PAO), baseline CT %PAO, most recent CT %PAO, and difference between the baseline and most recent %PAO on CT (Δ%PAO). RESULTS: A total of 354 patients had imaging reports available; 197 with CT and 315 with transthoracic echocardiography. The median follow-up time was 144 days (interquartile range [IQR], 102-186 days). RPVO was present in 38.9% of the 354 patients. The median Δ%PAO was -10.0% (IQR, -32% to -1.2%). Fewer patients with a provoked PE developed RPVO (P ≤ .01), and the initial troponin level was lower in patients who developed RPVO (P = .03). The initial thrombus was larger in the patients who received advanced intervention vs anticoagulation (baseline CT %PAO: median, 61.2%; [IQR, 27.5%-75.0%] vs median, 12.5% [IQR, 2.5%-40.0%]; P ≤ .0001). Catheter-directed thrombolysis (CDT; median Δ%PAO, -47.5%; IQR, -63.7% to -8.7%) and surgical pulmonary embolectomy (SPE; median Δ%PAO, -42.5; IQR, -68.1% to -18.7%) had the largest thrombus reduction compared with anticoagulation (P = .01). Of the 354 patients, 76 developed pulmonary hypertension; however, only 14 received pulmonary hypertension medications and 12 underwent pulmonary thromboendarterectomy. Cancer (odds ratio [OR], 1.7) and planned prolonged anticoagulation (>1 year; OR, 2.20) increased the risk of RPVO. In contrast, the risk was lower for men (OR, 0.61), patients with recent surgery (OR, 0.33), and patients treated with SPE (OR, 0.42). A larger Δ%PAO was found in men (coefficient, -8.94), patients with a lower body mass index (coefficient, -0.66), patients treated with CDT (coefficient, -18.12), and patients treated with SPE (coefficient, -21.69). A lower Δ%PAO was found in African-American patients (coefficient, 7.31). CONCLUSIONS: The use of CDT and SPE showed long-term benefit in thrombus reduction.

Outcomes and Predictors of Morbidity after Carotid Body Tumor Resection.

BACKGROUND: Carotid body tumors (CBTs) are uncommon neuroendocrine tumors at the carotid bifurcation treated with resection. The goal of this study was to examine patient outcomes after CBT resection and establish predictors of morbidity. METHODS: Patients undergoing CBT resection were identified from the National Surgical Quality Improvement Program (NSQIP) database over 11 years. Demographics, past medical history, preoperative labs, procedural details, morbidity and mortality were recorded. Multivariable logistic regression (MLR) analysis was performed to determine independent predictors of morbidity. RESULTS: From 2010 to 2020, 668 CBT resections were identified. The majority of patients were female (65%) and White (72%) with a mean age of 56 (standard deviation [SD] ± 16). Average body mass index (BMI) was 29.9 (SD ± 7.1). Arterial resection occurred in 81 patients (12%). 6% of patients experienced morbidity, most commonly re-operation (2.4%). Morbidity was more common in patients with higher BMI (33.1 vs. 29.7, P = 0.005), chronic obstruction pulmonary disease (10% vs. 1.9%, P = 0.012), higher American Society of Anesthesiologists (P = 0.005), and lower albumin (3.7 vs. 4, P = 0.016). Morbidity was not increased with arterial resection (P = 1) or based on length of operation (P = 0.169). Morbidity did not impact mortality (P = 0.06) though led to longer length of stay [LOS] (8 days vs. 2.4, P < 0.001). On MLR, preoperative BMI was the only risk factor for morbidity (odds ratio 1.06, 95% confidence interval 1.02-1.1, P = 0.005). CONCLUSIONS: CBT resection is very well tolerated with low stroke rates, morbidity, and mortality. Arterial resection leads to increased transfusion requirements and LOS but did not increase stroke rates, mortality, or overall morbidity. Within the NSQIP database, preoperative BMI was the only predictor of postoperative morbidity, which leads to significantly longer LOS.

Safety and efficacy of mechanical aspiration thrombectomy for patients with acute lower extremity ischemia.

OBJECTIVE: Acute limb ischemia (ALI) is associated with high rates of amputation and consequent morbidity and mortality. The objective of this study is to report on the safety and efficacy of aspiration thrombectomy using the Indigo Aspiration System in patients with lower extremity (LE) ALI. METHODS: The STRIDE study was an international, multicenter, prospective, study that enrolled 119 participants presenting with LE-ALI. Patients were treated firstline with mechanical thrombectomy using the Indigo Aspiration System, before stenting or angioplasty, or other therapies as determined by treating physician. The primary end point was target limb salvage at 30 days after the procedure. Secondary end points within 30 days included technical success, defined as core laboratory-adjudicated Thrombolysis in Myocardial Infarction (TIMI) 2/3 flow rate immediately after the procedure, changes in modified Society for Vascular Surgery runoff score, improvement of Rutherford classification compared with before the procedure, patency, rate of device-related serious adverse events, and major periprocedural bleeding. Secondary end points that will be evaluated at 12 months include target limb salvage and mortality. RESULTS: Of the 119 participants enrolled at 16 sites, the mean age was 66.3 years (46.2% female). At baseline (n = 119), ischemic severity was classified as Rutherford I in 10.9%, Rutherford IIa in 54.6%, and Rutherford IIb in 34.5%. The mean target thrombus length was 125.7 ± 124.7 mm. Before the procedure, 93.0% (of patients 107/115) had no flow (TIMI 0) through the target lesion. The target limb salvage rate at 30 days was 98.2% (109/111). The rate of periprocedural major bleed was 4.2% (5/119) and device-related serious adverse events was 0.8% (1/119). Restoration of flow (TIMI 2/3) was achieved in 96.3% of patients (105/109) immediately after the procedure. The median improvement in the modified Society for Vascular Surgery runoff score (before vs after the procedure) was 6.0 (interquartile range, 0.0-11.0). Rutherford classifications also improved after discharge in 86.5% of patients (83/96), as compared with preprocedural scores. Patency at 30 days was achieved in 89.4% of patients (101/113). CONCLUSIONS: In the STRIDE (A Study of Patients with Lower Extremity Acute Limb Ischemia to Remove Thrombus with the Indigo Aspiration System) study, aspiration thrombectomy with the Indigo System provided a safe and effective endovascular treatment for patients with LE-ALI, resulting in a high rate (98.2%) of successful limb salvage at 30 days, with few periprocedural complications.

Modified Frailty Index Helps Predict Mortality and Ambulation Differences Between Genders and Racial Differences Following Major Lower Extremity Amputation.

BACKGROUND: Major lower extremity amputation (LEA) is associated with significant morbidity and mortality. The modified frailty index (mFI-5) has been used to predict outcomes including ambulation and mortality after LEA. It remains unknown for which patient demographics the mFI-5 is a reliable predictor. METHODS: This was a retrospective review of all patients who underwent a first-time major LEA at our institution from 2015 to 2022. Patients were stratified into 2 risk groups based on their mFI-5 score: non-frail (mFI<3) and frail (mFI≥3) and assessed on outcomes. RESULTS: Our sample consisted of 687 patients of whom 134 (19.6%) were considered frail and 551 (80.4%) were considered non-frail. A higher mFI-5 is associated with decreased ambulation rates (OR: 0.565, P = .004), increased hospital readmission (OR: 1.657, P = .021), and increased mortality (OR: 2.101, P = .001) following major LEA. In African American patients, frail and non-frail patients differed on readmission at 90 days (P = .008), mortality at 1 year (P = .001), ambulatory status (P < .001), and prosthesis use (P = .023). In male patients, frail and non-frail patients differed on readmission at 90 days (P = .019), death at 1 year (P = .001), and ambulatory status (P = .002). In Caucasian patients and female patients, frail and non-frail patients did not differ significantly on outcomes. DISCUSSION: The mFI-5 is a valuable predictor of outcomes following major LEA, specifically in males and African American patients. Moreover, surgeons should consider using frailty status to risk stratify patients and inform treatment plans.

Opioid Use Disorder in Patients Undergoing Major Lower Extremity Amputation: Prevalence and Outcomes.

INTRODUCTION: Patients with a history of Opioid Use Disorder (OUD) have higher postoperative complication rates and mortality in many settings. Yet, it remains poorly understood how the opioid epidemic has affected patients undergoing major lower extremity amputation (LEA) and whether outcomes differ by OUD status. METHODS: We conducted a retrospective chart review of all 689 patients who underwent major LEA at a large tertiary referral center from 2015 to 2021. This study assessed patient characteristics and long-term postoperative outcomes for patients with preoperative OUD. RESULTS: 133 (19.3%) patients had a lifetime history of preoperative OUD. Preoperative OUD was associated with key characteristics, comorbidities, and outcome measures. OUD was significantly associated with younger age (P < .001), black race (P = .026), single relationship status (P < .001), BMI <30 (P = .024), no primary care provider (P = .004), and Medicaid insurance (P < .001). Comorbidities significantly associated with OUD include current smoking (P < .001), Human Immunodeficiency Virus (HIV; P = .003), and history of osteomyelitis (P < .001). Preoperative OUD independently predicted lower rates of 30-60-day readmission (odds ratio [OR] .54, P = .018) and 1-12-month reamputation (OR .41, P = .006). There was no significant difference in long-term mortality and follow-up. CONCLUSION: This study demonstrates the prevalence of OUD in patients undergoing major LEA and reports associations and long-term outcomes. Our findings highlight the importance of recognizing OUD and raise questions about the mechanisms underlying its relation to rates of postoperative readmission and reamputation.

Surgical treatment of nutcracker syndrome results in improved pain and quality of life.

BACKGROUND: Left renal vein (LRV) compression, or nutcracker phenomenon, describes the compression of the LRV, most commonly between the aorta and the superior mesenteric artery. The outflow obstruction that occurs from the compression causes venous hypertension leading to the development of pelvic collaterals, lumbar vein engorgement and gonadal vein reflux. The symptoms associated with LRV compression include abdominal pain, left flank pain, back pain, headache, pelvic pain/pressure, and hematuria. Symptomatic LRV compression can cause chronic pain and disability that impedes activities of daily living. Left renal auto transplantation (LR-AT) is one mode of treatment, leading to decreased pain with no significant vascular or urological complications. Herein we present a five patient case series with symptomatic LRV compression who underwent LR-AT with improved pain and quality of life after surgery. METHODS: Five patients underwent LR-AT between June 2020-December 2020 to resolve their symptomatic LRV compression. These patients were given three validated surveys pre- and post- intervention, then again at their three month follow up visit to assess their pain and health-related quality of life. RESULTS: The five patients were all female with the average age of 36.8 years old (36-41) and underwent LR-AT to treat their symptomatic LRV compression. The average Numeric Rating Scale (NRS) pain score pre intervention was 8.3 (range 6.7 to 10) which improved to pain rating 5.22 (range 2.7 to 6) post intervention, p-value = 0.013. The average pain NRS score at 3 month follow up was 3.86 (range 1.3-6), p-value = 0.006 when compared to pre-intervention pain scores. The average pain intensity pre intervention was 4.5 (4 to 5) and 2.7 (1 to 4.3) post intervention, p-value = 0.024. The average pain intensity score at 3 month follow up was 2.24 (range 1.3-3.3), p-value = 0.002 when compared to pre-intervention. The VascuQoL-6 survey score pre intervention averaged score of 9.6 (range 7-12) which improved to an average score of 20.6 (range 18-24), p-value = 0.001. The average VascuQoL score at 3 month follow up was 22.6 (range 22-24), p-value = < 0.001 when compared to pre intervention QoL scores all showing a statistically significant improvement of health-related quality of life. CONCLUSION: The diagnosis of LRV compression can be challenging due to the non-descript symptoms and overall lack of awareness. Understanding venous tributary pathways and drainage can help clarify why patients present with unusual symptoms. Surgical treatment of LRV compression through LR-AT can improve patients' pain and improve vascular quality of life.

Diameter and depth of femoral vessels by duplex ultrasound.

BACKGROUND: The anatomy of the femoral artery and vein plays an integral role in vascular access. Both technical feasibility and complication rates are associated with femoral vessel diameter and depth. The goal of this study is to establish normative values for common femoral artery (CFA) and vein (CFV) depth and diameter using a large, diverse patient population. METHODS: A retrospective review of all patients undergoing lower extremity venous duplex imaging over a 1 year period were reviewed. Patients with inadequate imaging or with evidence of deep vein thrombosis were excluded. The index image of all studies was a non-compressed view of the common femoral vein at the saphenous-femoral junction. All measurements were taken from this still. Vessel diameters were measured from intima to intima. Depth was measured from skin to intima. BMI and BSA were calculated using standard formulas. Chi square was used for univariate analysis. Linear regression was used to establish correlation. RESULTS: Over the 1 year period, 983 patients met criteria for inclusion. The majority were male (53%) with a mean age of 55. The patients were 47% white and 44% black. The majority had hypertension (53%). The mean BMI and BSA were 29 and 2, respectively. Mean CFA depth was 1.7 cm, while mean CFV depth was 1.8 cm. The mean CFA and CFV diameters were 0.9 and 1.1 cm, respectively. Amongst height, weight, BMI, and BSA, weight correlated best with CFA (R = 0.548) and CFV (R = 0.552) depth, while BSA correlated best for diameter for both CFA (R = 0.390) and CFV (R = 0.440). CONCLUSIONS: This study establishes mean diameters and depths for the common femoral artery and vein using a large, diverse patient group. BSA was most closely associated with vessel diameter, while weight was correlated with depth. This study provides normative diameter and depth values for the common femoral vasculature, which may assist in vascular access planning for providers.

Percutaneous Aortoiliac Thromboendarterectomy for Acute Limb Ischemia.

Aortoiliac occlusive disease (AIOD) can occur from either chronic, progressive atherosclerotic disease, acute on chronic thrombosis or acute arterial embolism, and can all result in limb ischemia. Bypass surgery had long been the gold standard for treatment for AIOD, however, with advances in endovascular techniques, minimally invasive treatment of aortoiliac lesions has become the first line choice of management in many cases. Herein, we describe a case of utilizing the Inari ClotTriever to perform aortoiliac mechanical thrombectomy and the ARTIX thrombectomy system to perform an embolectomy the superficial femoral artery, highlighting new therapies to treat AIOD.

Neutrophil-to-Lymphocyte Ratio as a Predictor of Mortality for COVID-19-Related Acute Respiratory Distress Syndrome (ARDS) Patients Requiring Extracorporeal Membrane Oxygenation Therapy.

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) has been studied as an indicator of systemic inflammation and as a prognostic tool in multiple areas of medicine. Previous research has suggested that higher NLR and rapid increase to peak NLR are associated with poorer outcomes in patients with coronavirus disease 2019 (COVID-19), particularly in those experiencing acute respiratory distress syndrome (ARDS). Within vascular surgery, there is data to suggest a positive correlation between elevated pre-extracorporeal membrane oxygenation (ECMO) NLR and higher rates of mortality following major procedures. This study explores the prognostic value of peri-ECMO NLR in patients requiring veno-venous ECMO (VV-ECMO) therapy for COVID-19-related ARDS. The objective of this study was to explore the utility of pre-ECMO NLR as an easily accessible prognostic factor for patients suffering from COVID-19-associated ARDS that require VV-ECMO. METHODS: This was a retrospective cohort study within a tertiary care hospital conducted between April 2020 and January 2021. Patients requiring VV-ECMO therapy for COVID-19-associated ARDS were included. Peri-ECMO NLR values, length of stay (LOS), duration on VV-ECMO, and discharge status were recorded. Receiver operating characteristic (ROC) curve analysis and Youden's J statistics were performed to calculate a cut-off value of 11.005 for pre-ECMO NLR and 17.616 for on-ECMO NLR. Pre-ECMO and on-ECMO Kaplan-Meyer curves were generated for two groups of patients, those above and below NLR cutoff thresholds. Two-sample T-test was performed to test for significant differences in LOS and duration on VV-ECMO. RESULTS: Twenty-six patients were included in the study for final analyses. There was an overall mortality of 39% (n = 10). ROC curve analysis and Youden's J statistic revealed an optimal cut-off value of pre-ECMO NLR = 11.005 and on-ECMO NLR = 17.616. Results showed that the patient group placed on VV-ECMO with a pre-ECMO NLR less than 11.005 experienced no mortality (n = 7) and a median LOS of 28 days (IQR = 14.5-64.5 days). The patient group on VV-ECMO with a pre-ECMO NLR greater than 11.005 (n = 19) included all mortality (n = 10) and had a median LOS of 49 days (IQR = 25.5-63.5 days). The patient group with on-ECMO NLR less than 17.616 also conferred a survival advantage. There was no significant difference in LOS or duration on VV-ECMO between the two groups, pre-ECMO or on-ECMO. CONCLUSIONS:  A pre-ECMO NLR cutoff was identified and offered statistically significant prognostic value in predicting mortality. A lower on-ECMO NLR value also indicated a survival advantage. Future studies should include NLR within multivariate models to better discern the effect of NLR and elucidate how it can be factored into clinical decision-making. Importantly, this data can be expanded to assess the predictive value of NLR pertaining to the COVID-19-induced ARDS population and matched cohorts.

Trauma-Induced Median Arcuate Ligament Syndrome is an Under-Recognized Source of Chronic Abdominal Pain.

Median arcuate ligament syndrome (MALS) can be a debilitating condition resulting in epigastric pain, nausea, difficulty eating due to postprandial pain, weight loss, and malnutrition in otherwise healthy individuals. The pain is caused by the compression of the celiac artery and neural ganglia by the median arcuate ligament as it attaches from the spine to the diaphragm. Diagnostic imaging, either duplex or angiography, can show the abnormality however, vague symptoms can lead to a missed diagnosis. While MALS is a known anatomical variation in the population, to our knowledge, has not been identified to be caused by trauma. Here, we present 4 patients who developed MALS following abdominal or spinal trauma whom all required surgery to alleviate lifestyle-limiting pain.

Comparison of Pre-existing Mood Disorders and Chronic Kidney Disease as Predictors of Ambulatory Status After Major Limb Amputation.

Objective We aim to compare the effects of pre-existing mood disorders and chronic kidney disease (CKD) on ambulation outcomes for patients who have undergone major lower extremity amputation (MLEA) while also stratifying by the presence of social factors. Methods  We performed a retrospective chart review of 700 patients admitted from 2014 to 2022 who underwent MLEA. We performed Chi-square tests and binomial logistic regression with p < 0.05 as our significance level. Results Mood disorder patients have higher rates of independent ambulation if they have familial support (p = 0.022), a listed primary care provider (PCP; p = 0.013), a six-month follow-up (p < 0.001), or a one-year follow-up (p < 0.001). Patients with a history of mood disorder have significantly decreased odds of prosthesis usage (OR: 0.58, 95% CI: 0.40-0.86) but have higher rates of prosthesis usage if they have familial support (p = 0.002), a PCP listed (p = 0.005), a six-month follow-up (p < 0.001), or a one-year follow-up (p < 0.001). CKD patients have significantly decreased odds of eventual independent ambulation (OR: 0.69, 95% CI: 0.49-0.97) but have significantly increased rates of independent ambulation if they have familial support (p =0.041) and six-month (p < 0.001) or one-year follow-up (p < 0.001). CKD patients only have significant changes in prosthesis usage with a six-month (p < 0.001) or one-year follow-up (p < 0.001). Conclusions Pre-existing CKD and mood disorders are associated with decreased odds of independent ambulation and prosthesis usage, respectively. Social factors such as family support, a listed PCP, and timely follow-up are associated with markedly improved ambulatory outcomes for MLEA patients with mood disorders and CKD, with significantly improved prosthesis usage outcomes in only the mood disorder population.

Chronic Kidney Disease Predicts Greater 5-Year Mortality Following Major Limb Amputation.

Severe chronic kidney disease (CKD) predicts greater mortality after major lower extremity amputation (MLEA), but it remains poorly understood whether this finding extends to patients with earlier stages of CKD. We assessed outcomes for patients with CKD in a retrospective chart review of all patients who underwent MLEA at a large tertiary referral center from 2015 to 2021. We stratified 398 patients by glomerular filtration rate (GFR) and conducted Chi-Square and survival analysis. Preoperative CKD diagnosis was associated with many comorbidities, less 1-year follow-up, and greater 1- and 5-year mortality. Kaplan-Meier analysis showed worse 5-year survival for patients with any stage of CKD (62%) compared to patients without CKD (81%; P < .001). Greater 5-year mortality was independently predicted by moderate CKD (hazard ratio (HR) 2.37, P = .02) as well as severe CKD (HR 2.09, P = .005). These findings demonstrate the importance of identifying and treating CKD early preoperatively.

Back Pain and Right Leg Swelling: Unusual Presentations of May-Thurner Syndrome.

May-Thurner (MT) syndrome refers to compression of the left common iliac vein by the right common iliac artery. Symptoms reported are generally left-sided leg swelling or pain. It is unusual for patients to report right-sided symptoms that are alleviated by treating MT compression. This case series describes three patients who had right-sided symptoms caused by left-sided venous compression. A retrospective chart review identified three patients over a year who presented with a variety of symptoms, including right-leg pain and swelling, and underwent treatment with left-sided venous compressions with a resolution of symptoms. Three patients were identified with right-sided back and flank pain. Venography with intravascular ultrasound (IVUS) showed the MT compression was greater than 75% in each case (mean 80.3% with a range of 75.7%-95%), and all patients were treated by decompressing the venous outflow obstruction by stenting the left common iliac vein, which relieved their symptoms. Venous compressions that occur on the anatomical left side can lead to right-sided symptoms. In patients reporting right-sided back and flank pain, MT should be considered in the differential diagnosis.

Predictive Factors for Mortality Following Major Lower Extremity Amputation.

BACKGROUND: Despite advances in techniques and care, major amputation bears a high risk for mortality. Previously identified factors associated with increased risk of mortality include amputation level, renal function, and pre-operative white cell count. METHODS: A single center retrospective chart review was conducted identifying patients who had undergone a major amputation. Chi-squared, t-testing, and Cox proportional hazard modeling were performed examining death at 6 months and 12 months. RESULTS: Factors associated with an increased risk of six-month mortality include age (OR 1.01-1.05, P < .001), sex (OR 1.08-3.24, P < .01), minority race (OR 1.18-18.19, P < .01), chronic kidney disease (OR 1.40-6.06, P < .001), and use of pressors at the induction of anesthesia for index amputation (OR 2.09-7.85, P < .000). Factors associated with increased risk of 12 month mortality were similar. DISCUSSION: Patients undergoing major amputation continue to suffer high mortality. Those patients who received their amputation under physiologically stressful conditions were more likely to die within 6 months. Reliably predicting six-month mortality can assist surgeons and patients in making appropriate care decisions.

Intravascular ultrasound imaging for diagnosis and characterization of the popliteal compression syndrome.

Objective: Functional popliteal artery entrapment syndrome (fPAES) is a rare form of nonatherosclerotic claudication most often seen in young athletic patients. Diagnosis remains challenging, with various imaging modalities showing equivocal or subtle findings that may be missed. We sought to critically examine and quantitate the utility of intravascular ultrasound (IVUS) imaging, a common diagnostic tool for vascular compression syndromes, in diagnosis and characterization of fPAES. Methods: Patients presenting to a single tertiary care center between 2019 and 2022 with symptoms of PAES but without an anatomic etiology or equivocal workup were selected. Angiogram and IVUS with maneuvers were performed on affected extremities at rest, active plantarflexion/dorsiflexion, and plantarflexion/dorsiflexion against resistance. IVUS examination was recorded using a pull-back technique from the tibial vessels to the superficial femoral artery. The degree, length, and anatomic location of compression using the two imaging modalities were compared. Results: Angiogram and IVUS with maneuvers were performed on 17 lower extremities (9 left, 8 right) in 15 patients (88% female; mean age, 21.2 years). Evidence of arterial compression on angiography was noted in 88.2% (n = 15) of limbs (66.7% complete contrast cessation and 20% popliteal artery tapering); 13.3% (n = 2) only demonstrated sluggish flow as possible evidence of compression. Arterial compression was seen on IVUS imaging in 15 of 17 limbs, and all completely compressed around the IVUS catheter. The IVUS-measured mean length of compression was 10.5 cm ± 4.2 (median, 11 cm; range, 4-23 cm). Compression involved only the popliteal vessels in 86.7% (n = 13); one patient had both popliteal and tibioperoneal trunk compression, whereas another had tibioperoneal trunk and peroneal artery compression. Popliteal vein compression was 100%. The contrast cessation point on angiography and the proximal point of compression on IVUS imaging differed in 80% of cases (P < .05). The distal extent of compression was unable to be determined by angiogram findings but was clearly delineated by IVUS imaging in all cases. Conclusions: IVUS imaging is a more sensitive diagnostic and descriptive imaging modality compared with angiogram in patients with possible fPAES. IVUS and angiogram findings are greatly discordant; moreover, IVUS imaging can provide detailed information such as the precise extent and anatomic location of the arterial compression, which may be useful in aiding surgical planning. IVUS imaging should be considered the gold standard for diagnosing and characterizing fPAES before intervention planning.