Tissue-Specific Macrophage Responses to Remote Injury Impact the Outcome of Subsequent Local Immune Challenge.

Myocardial infarction, stroke, and sepsis trigger systemic inflammation and organism-wide complications that are difficult to manage. Here, we examined the contribution of macrophages residing in vital organs to the systemic response after these injuries. We generated a comprehensive catalog of changes in macrophage number, origin, and gene expression in the heart, brain, liver, kidney, and lung of mice with myocardial infarction, stroke, or sepsis. Predominantly fueled by heightened local proliferation, tissue macrophage numbers increased systemically. Macrophages in the same organ responded similarly to different injuries by altering expression of tissue-specific gene sets. Preceding myocardial infarction improved survival of subsequent pneumonia due to enhanced bacterial clearance, which was caused by IFNÉ£ priming of alveolar macrophages. Conversely, EGF receptor signaling in macrophages exacerbated inflammatory lung injury. Our data suggest that local injury activates macrophages in remote organs and that targeting macrophages could improve resilience against systemic complications following myocardial infarction, stroke, and sepsis.

Drug-Eluting Resorbable Scaffold versus Angioplasty for Infrapopliteal Artery Disease.

BACKGROUND: Among patients with chronic limb-threatening ischemia (CLTI) and infrapopliteal artery disease, angioplasty has been associated with frequent reintervention and adverse limb outcomes from restenosis. The effect of the use of drug-eluting resorbable scaffolds on these outcomes remains unknown. METHODS: In this multicenter, randomized, controlled trial, 261 patients with CLTI and infrapopliteal artery disease were randomly assigned in a 2:1 ratio to receive treatment with an everolimus-eluting resorbable scaffold or angioplasty. The primary efficacy end point was freedom from the following events at 1 year: amputation above the ankle of the target limb, occlusion of the target vessel, clinically driven revascularization of the target lesion, and binary restenosis of the target lesion. The primary safety end point was freedom from major adverse limb events at 6 months and from perioperative death. RESULTS: The primary efficacy end point was observed (i.e., no events occurred) in 135 of 173 patients in the scaffold group and 48 of 88 patients in the angioplasty group (Kaplan-Meier estimate, 74% vs. 44%; absolute difference, 30 percentage points; 95% confidence interval [CI], 15 to 46; one-sided P<0.001 for superiority). The primary safety end point was observed in 165 of 170 patients in the scaffold group and 90 of 90 patients in the angioplasty group (absolute difference, -3 percentage points; 95% CI, -6 to 0; one-sided P<0.001 for noninferiority). Serious adverse events related to the index procedure occurred in 2% of the patients in the scaffold group and 3% of those in the angioplasty group. CONCLUSIONS: Among patients with CLTI due to infrapopliteal artery disease, the use of an everolimus-eluting resorbable scaffold was superior to angioplasty with respect to the primary efficacy end point. (Funded by Abbott; LIFE-BTK ClinicalTrials.gov number, NCT04227899.).

Update on Hemodialysis-Induced Multiorgan Ischemia: Brains and Beyond.

Hemodialysis is a life-saving treatment for patients with kidney failure. However, patients requiring hemodialysis have a 10-20 times higher risk of cardiovascular morbidity and mortality than that of the general population. Patients encounter complications such as episodic intradialytic hypotension, abnormal perfusion to critical organs (heart, brain, liver, and kidney), and damage to vulnerable vascular beds. Recurrent conventional hemodialysis exposes patients to multiple episodes of circulatory stress, exacerbating and being aggravated by microvascular endothelial dysfunction. This promulgates progressive injury that leads to irreversible multiorgan injury and the well-documented higher incidence of cardiovascular disease and premature death. This review aims to examine the underlying pathophysiology of hemodialysis-related vascular injury and consider a range of therapeutic approaches to improving outcomes set within this evolved rubric.‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬.

Bilateral Femoral Cannulation Is Associated With Reduced Severe Limb Ischemia-Related Complications Compared With Unilateral Femoral Cannulation in Adult Peripheral Venoarterial Extracorporeal Membrane Oxygenation: Results From the Extracorporeal Life Support Registry.

OBJECTIVES: Peripheral venoarterial extracorporeal membrane oxygenation (ECMO) with femoral access is obtained through unilateral or bilateral groin cannulation. Whether one cannulation strategy is associated with a lower risk for limb ischemia remains unknown. We aim to assess if one strategy is preferable. DESIGN: A retrospective cohort study based on the Extracorporeal Life Support Organization registry. SETTING: ECMO centers worldwide included in the Extracorporeal Life Support Organization registry. PATIENTS: All adult patients (≥ 18 yr) who received peripheral venoarterial ECMO with femoral access and were included from 2014 to 2020. INTERVENTIONS: Unilateral or bilateral femoral cannulation. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the occurrence of limb ischemia defined as a composite endpoint including the need for a distal perfusion cannula (DPC) after 6 hours from implantation, compartment syndrome/fasciotomy, amputation, revascularization, and thrombectomy. Secondary endpoints included bleeding at the peripheral cannulation site, need for vessel repair, vessel repair after decannulation, and in-hospital death. Propensity score matching was performed to account for confounders. Overall, 19,093 patients underwent peripheral venoarterial ECMO through unilateral ( n = 11,965) or bilateral ( n = 7,128) femoral cannulation. Limb ischemia requiring any intervention was not different between both groups (bilateral vs unilateral: odds ratio [OR], 0.92; 95% CI, 0.82-1.02). However, there was a lower rate of compartment syndrome/fasciotomy in the bilateral group (bilateral vs unilateral: OR, 0.80; 95% CI, 0.66-0.97). Bilateral cannulation was also associated with lower odds of cannulation site bleeding (bilateral vs unilateral: OR, 0.87; 95% CI, 0.76-0.99), vessel repair (bilateral vs unilateral: OR, 0.55; 95% CI, 0.38-0.79), and in-hospital mortality (bilateral vs unilateral: OR, 0.85; 95% CI, 0.81-0.91) compared with unilateral cannulation. These findings were unchanged after propensity matching. CONCLUSIONS: This study showed no risk reduction for overall limb ischemia-related events requiring DPC after 6 hours when comparing bilateral to unilateral femoral cannulation in peripheral venoarterial ECMO. However, bilateral cannulation was associated with a reduced risk for compartment syndrome/fasciotomy, lower rates of bleeding and vessel repair during ECMO, and lower in-hospital mortality.

Slowly moving the needle away from Fistula First.

OBJECTIVE: In 2019, the management of end-stage kidney disease (ESKD) shifted away from "Fistula First" (FF) to "ESKD Life-Plan: Patient Life-Plan First then Access Needs." Indeed, some patients exhibit such excessive comorbidity that even relatively minor vascular surgery may be complicated. The purpose of this study was to retrospectively assess complications and mortality (and delineate operative futility) in patients undergoing arteriovenous fistula (AVF) creation in the FF era. METHODS: Consecutive AVFs created in a single institution before 2021 were retrospectively reviewed. Operative futility was defined as never-accessed fistula, no initiation of dialysis, failure of access maturation (despite secondary intervention), hemodialysis access-induced distal ischemia requiring ligation, early loss of secondary patency, and/or patient mortality within the first 6 postoperative months. RESULTS: A total of 401 AVFs were created including radial-cephalic (44%), brachial-cephalic (41%), and brachial-basilic (15%) constructions. Patients exhibited a mean age of 69 ± 15 years; 63% were male, and most (74%) were already being hemodialyzed at the time of fistula creation. Forty-five patients (11%) suffered a cardiac event, and five patients died (1%) within 90 days of their access surgery. Perioperative cardiac events were significantly more common after age 80 (19% vs 8%; P = .004); age >80 years was an independent predictor of major 90-day complications (odds ratio [OR], 1.88; 95% confidence interval [CI], 1.04-3.39; P = .036) and the sole independent predictor of major morbidity defined as cardiopulmonary complications, stroke, or death within the first year (OR, 2.01; 95% CI, 1.24-3.25; P = .004). Operative futility was encountered in 52% of the cohort (n = 208 patients): 40% (n = 160) of primary AVFs failed to mature despite assistance, 19% (n = 77) had lost secondary patency by 6 months, 13% of patients (n = 53) were never started on dialysis after access creation, 4% (n = 16) were dead by 6 months, 2% of AVFs (n = 10) matured but were never accessed, and 2% (n = 9) required ligation for hemodialysis access-induced distal ischemia. Not surprisingly, the sole independent protector against operative futility was that catheter-based dialysis had been established prior to AVF creation (OR, 0.36; 95% CI, 0.22-0.59; P < .01). CONCLUSIONS: Approximately 50% of primary AVF operations performed in the aggressive FF era were deemed futile. Octogenarians were particularly prone to futility and complications during this era. A paradigm shift, from FF to an "ESKD Life-Plan" will, hopefully, more thoughtfully match vascular access strategies to individual patient needs.

Revascularization for claudication: Changing the natural history of a benign disease!

OBJECTIVE: The benign natural history of intermittent claudication was first documented in 1960 and has been reconfirmed in several subsequent studies. Excellent outcomes in patients with intermittent claudication can be achieved with exercise therapy and optimal medical management. Professional society guidelines have clearly stated that revascularization procedures should be performed only in patients with incapacitating claudication who have failed conservative therapy. Despite these guidelines, revascularization procedures, primarily percutaneous interventions, have been increasingly utilized in patients with claudication. Many of these patients are not even offered an attempt at medical therapy, and those who are often do not undergo a full course of treatment. Many studies document significant reintervention rates following revascularization, which are associated with increased rates of acute and chronic limb ischemia that may result in significant rates of amputation. The objectives of this study were to compare outcomes of conservative therapy to those seen in patients undergoing revascularization procedures and to determine the impact of revascularization on the natural history of claudication. METHODS: Google Scholar and PubMed were searched for manuscripts on the conservative management of claudication and for those reporting outcomes following revascularization for claudication. RESULTS: Despite early improvement in claudication symptoms following revascularization, multiple studies have demonstrated that long-term outcomes following revascularization are often no better than those obtained with conservative therapy. High reintervention rates (up to 43% for tibial atherectomies) result in high rates of both acute and chronic limb ischemia as compared with those patients undergoing medical therapy. In addition, amputation rates as high as 11% on long-term follow-up are seen in patients undergoing early revascularization. These patients also have a higher incidence of adverse cardiovascular events such as myocardial infarctions compared with patients treated medically. CONCLUSIONS: Revascularization procedures negatively impact the natural history of claudication often resulting in multiple interventions, an increase in the incidence of acute and chronic limb ischemia, and an increased risk of amputation. Accordingly, informed consent requires that all patients undergoing early revascularization must be appraised of the potential negative impact of revascularization on the natural history of claudication.

Recent developments in targets for ischemic foot disease.

Diabetes is a key risk factor for ischaemic foot disease, which causes pain, tissue loss, hospital admission, and major amputation. Currently, treatment focuses on revascularisation, but many patients are unsuitable for surgery and revascularisation is frequently unsuccessful. The authors describe recent research in animal models and clinical trials investigating novel medical targets for ischaemia, including theories about impaired wound healing, animal models for limb ischaemia and recent randomised controlled trials testing novel medical therapies. Novel targets identified in animal models included stimulating mobilisation of CD34+ progenitor cells through upregulating oncostatin M or microRNA-181, downregulating tumour necrosis factor superfamily member 14, or activating the Wingless pathway. Within the ischaemic limb vasculature, upregulation of apolipoprotein L domain containing 1, microRNA-130b or long noncoding RNA that enhances endothelial nitric oxide synthase expression promoted limb blood supply recovery, angiogenesis, and arteriogenesis. Similarly, administration of soluble guanylate cyclase stimulators riociguat or praliciguat or 3-ketoacyl-CoA thiolase inhibitor trimetazidine promoted blood flow recovery. Translating pre-clinical findings to patients has been challenging, mainly due to limitations in clinically translatable animal models of human disease. Promising results have been reported for administering plasmids encoding hepatocyte growth factor or intra-arterial injection of bone marrow derived cells in small clinical trials. It remains to be seen whether these high resource therapies can be developed to be widely applicable. In conclusion, an ever-expanding list of potential targets for medical revascularisation is being identified. It is hoped that through ongoing research and further larger clinical trials, these will translate into new broadly applicable therapies to improve outcomes.

Machine Perfusion Deters Ischemia-Related Derangement of a Rodent Free Flap: Development of a Model.

INTRODUCTION: Machine perfusion can enable isolated support of composite tissues, such as free flaps. The goal of perfusion in this setting is to preserve tissues prior to transplantation or provide transient support at the wound bed. This study aimed to establish a rodent model of machine perfusion in a fasciocutaneous-free flap to serve as an affordable testbed and determine the potential of the developed support protocol to deter ischemia-related metabolic derangement. METHODS: Rat epigastric-free flaps were harvested and transferred to a closed circuit that provides circulatory and respiratory support. Whole rat blood was recirculated for 8 h, while adjusting the flow rate to maintain arterial-like perfusion pressures. Blood samples were collected during support. Extracellular tissue lactate and glucose levels were characterized with a microdialysis probe and compared with warm ischemic, cold ischemic, and anastomosed-free flap controls. RESULTS: Maintenance of physiologic arterial pressures (85-100 mmHg) resulted in average pump flow rates of 360-430 µL/min. Blood-based measurements showed maintained glucose and oxygen consumption throughout machine perfusion. Average normalized lactate to glucose ratio for the perfused flaps was 5-32-fold lower than that for the warm ischemic flap controls during hours 2-8 (P < 0.05). CONCLUSIONS: We developed a rat model of ex vivo machine perfusion of a fasciocutaneous-free flap with maintained stable flow and tissue metabolic activity for 8 h. This model can be used to assess critical elements of support in this setting as well as explore other novel therapies and technologies to improve free tissue transfer.

Development of the AMPDECIDE Decision Aid to Facilitate Shared Decision Making in Patients Facing Amputation Secondary to Chronic Limb Threatening Ischemia.

INTRODUCTION: We developed a patient decision aid to enhance patient participation in amputation level decision making when there is a choice between a transmetatarsal or transtibial amputation. METHODS: In accordance with International Patient Decision Aid Standards, we developed an amputation level patient decision aid for patients who are being considered for either a transmetatarsal or transtibial amputation, incorporating qualitative literature data, quantitative literature data, qualitative provider and patient interviews, expert panel input and iterative patient feedback. RESULTS: The rapid qualitative literature review and qualitative interviews identified five domains outcome priority domains important to patients facing amputation secondary to chronic limb threatening ischemia: 1) the ability to walk, 2) healing and risk for reamputation, 3) rehabilitation program intensity, 4) ease of prosthetic use, and 5) limb length after amputation. The rapid quantitative review identified only two domains with adequate evidence comparing differences in outcomes between the two amputation levels: mobility and reamputation. Patient, surgeon, rehabilitation and decision aid expert feedback allowed us to integrate critical facets of the decision including addressing the emotional context of loss of limb, fear and anxiety as an obstacle to decision making, shaping the decision in the context of remaining life years, and how to facilitate patient knowledge of value tradeoffs. CONCLUSIONS: Amputation level choice is associated with significant outcome trade-offs. The AMPDECIDE patient decision aid can facilitate acknowledgment of patient fears, enhance knowledge of amputation level outcomes, assist patients in determining their personal outcome priorities, and facilitate shared amputation level decision making.

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.

Luminal Delivery of Pectin-Modified Oxygen Microbubbles Mitigates Rodent Experimental Intestinal Ischemia.

INTRODUCTION: Ischemic gut injury is common in the intensive care unit, impairs gut barrier function, and contributes to multiorgan dysfunction. One novel intervention to mitigate ischemic gut injury is the direct luminal delivery of oxygen microbubbles (OMB). Formulations of OMB can be modified to control the rate of oxygen delivery. This project examined whether luminal delivery of pectin-modified OMB (OMBp5) can reduce ischemic gut injury in a rodent model. METHODS: The OMBp5 formulation was adapted to improve delivery of oxygen along the length of small intestine. Adult Sprague-Dawley rats (n = 24) were randomly allocated to three groups: sham-surgery (SS), intestinal ischemia (II), and intestinal ischemia plus luminal delivery of OMBp5 (II + O). Ischemia-reperfusion injury was induced by superior mesenteric artery occlusion for 45 min followed by reperfusion for 30 min. Outcome data included macroscopic score of mucosal injury, the histological score of gut injury, and plasma biomarkers of intestinal injury. RESULTS: Macroscopic, microscopic data, and intestinal injury biomarker results demonstrated minimal intestinal damage in the SS group and constant damage in the II group. II + O group had a significantly improved macroscopic score throughout the gut mucosa (P = 0.04) than the II. The mean histological score of gut injury for the II + O group was significantly improved on the II group (P ≤ 0.01) in the proximal intestine only, within 30 cm of delivery. No differences were observed in plasma biomarkers of intestinal injury following OMBp5 treatment. CONCLUSIONS: This proof-of-concept study has demonstrated that luminal OMBp5 decreases ischemic injury to the proximal small intestine. There is a need to improve oxygen delivery over the full length of the intestine. These findings support further studies with clinically relevant end points, such as systemic inflammation and vital organ dysfunction.

Treatment Location Variation for Chronic Limb-Threatening Ischemia in Patients With Kidney Failure.

INTRODUCTION: End-stage kidney disease (ESKD) is an established risk factor for chronic limb-threatening ischemia (CLTI). Procedural location for ESKD patients has not been well described. This study aims to examine variation in index procedural location in ESKD versus non-ESKD patients undergoing peripheral vascular intervention for CLTI and identify preoperative risk factors for tibial interventions. METHODS: Chronic limb-threatening ischemia (CLTI) patients were identified in the Vascular Quality Initiative (VQI) peripheral vascular intervention dataset. Patient demographics and comorbidities were compared between patients with and without ESKD and those undergoing index tibial versus nontibial interventions. A multivariable logistic regression evaluating risk factors for tibial intervention was conducted. RESULTS: A total of 23,480 procedures were performed on CLTI patients with 13.6% (n = 3154) with ESKD. End-stage kidney disease (ESKD) patients were younger (66.56 ± 11.68 versus 71.66 ± 12.09 y old, P = 0.019), more often Black (40.6 versus 18.6%, P < 0.001), male (61.2 versus 56.5%, P < 0.001), and diabetic (81.8 versus 60.0%, P < 0.001) than non-ESKD patients. Patients undergoing index tibial interventions had higher rates of ESKD (19.4 versus 10.6%, P < 0.001) and diabetes (73.4 versus 57.5%, P < 0.001) and lower rates of smoking (49.9 versus 73.0%, P < 0.001) than patients with nontibial interventions. ESKD (odds ratio (OR) 1.67, 95% confidence interval (CI) 1.52-1.86, P < 0.001), Black race (OR 1.19, 95% CI 1.09-1.30, P < 0.001), and diabetes (OR 1.82, 95% CI 1.71-2.00, P < 0.001) were risk factors for tibial intervention. CONCLUSIONS: Patients with ESKD and CLTI have higher rates of diabetes and tibial disease and lower rates of smoking than non-ESKD patients. Tibial disease was associated with ESKD, diabetes, and Black race.

Percutaneous Management of Dialysis Access Steal Syndrome: Interventions and Outcomes from a Single Institution's 20-Year Experience.

PURPOSE: To determine safety and effectiveness of percutaneous interventions performed by interventional radiologists at a single institution over 2 decades in patients with dialysis access steal syndrome (DASS). MATERIALS AND METHODS: A retrospective review of fistulograms from 2001 to 2021 (N = 11,658) was performed. In total, 286 fistulograms in 212 patients with surgically created dialysis accesses met inclusion criterion of fistulography for suspected DASS. Chart review collected data regarding patient demographics, comorbidities, access characteristics, fistulography findings, intervention(s) performed, and outcomes. Procedures with and without DASS intervention were compared. Odds ratios (ORs), adjusted for age, sex, comorbidities, access characteristics, and multiple within-patient events, were calculated using logistic regression to determine associations between steal intervention status and outcome variables: (a) major adverse events, (b) access preservation, and (c) follow-up surgery. A percutaneously treatable cause of DASS was present in 128 cases (45%). Treatment of DASS lesions was performed in 118 cases. Fifteen embolizations were also performed in patients without DASS lesions. RESULTS: Technical success of DASS interventions, defined by the Society of Interventional Radiology (SIR) reporting standards, was 94%; 54% of interventions resulted in DASS symptom improvement at a median follow-up of 15 days. Patients with steal intervention had 60% lower odds of follow-up surgery (OR, 0.4; P = .007). There was no difference in major adverse events (P = .98) or access preservation (P = .13) between groups. CONCLUSIONS: In this retrospective cohort study, approximately half of DASS fistulograms revealed a percutaneously treatable cause of steal. Over half of DASS interventions resulted in symptomatic relief. Percutaneous intervention was associated with lower odds of follow-up surgery without compromising access preservation.

Risk Factors, Incidence, and Outcomes Associated With Clinically Significant Airway Ischemia.

Airway complications following lung transplantation remain an important cause of morbidity and mortality. We aimed to identify the incidence, risk factors and outcomes associated with clinically significant airway ischemia (CSAI) in our center. We reviewed 217 lung transplants (386 airway anastomoses) performed at our institution between February 2016 and December 2020. Airway images were graded using the 2018 ISHLT grading guidelines modified slightly for retrospective analysis. Airways were considered to have CSAI if they developed ischemia severity >B2, stenosis >50%, and/or any degree of dehiscence within 6-months of transplant. Regression analyses were used to evaluate outcomes and risk factors for CSAI. Eighty-two patients (37.8%) met criteria for CSAI. Of these, twenty-six (32%) developed stenosis and/or dehiscence, and 17 (21%) required interventions. Patients with CSAI had lower one-year (80.5% vs. 91.9%, p = 0.05) and three-year (67.1% vs. 77.8%, p = 0.08) survival than patients without CSAI. Factors associated with CSAI included younger recipient age, recipient diabetes, single running suture technique, performance of the left anastomosis first, lower venous oxygen saturation within 48-h, and takeback for major bleeding. Our single-center analysis suggests that airway ischemia remains a major obstacle in contemporary lung transplantation. Improving the local healing milieu of the airway anastomosis could potentially mitigate this risk.

Cross-Limb Vascular Shunting for Traumatic Popliteal Artery Injury.

BACKGROUND: Popliteal artery injury (PAI) is a challenging trauma that requires prompt and accurate treatment since the probability of lower-limb amputation increases with the ischemic time. Intravascular shunting and cross-limb vascular shunting (CLS) are used as temporary vascular shunting (TVS) methods to shorten the ischemic time for limb vascular injury. CLS involves sending blood from an artery in a healthy body part to a peripheral vessel in an injured part to immediately resume blood flow to the injured limb. For closed injuries including PAI, CLS may be performed without exploring and identifying the arterial stumps and it enables early reperfusion to the ischemic limb. We report the case series of traumatic PAI treated using CLS and verify the usefulness of CLS. METHODS: All patients with traumatic PAI treated with CLS at our institution between August 2013 and December 2021 were included. Demographic and clinical patient characteristics were extracted from the medical records. Comorbid injuries, severity of acute limb ischemia based on the Rutherford grading scale, time from injury to reperfusion by CLS, time from injury to completion of artery, and the use of fasciotomy were investigated. As outcomes, we investigated the presence or absence of lower extremity amputation during the course of treatment. RESULTS: We used CLS as treatment for 5 cases with traumatic PAI. Based on the Rutherford grading scale for acute limb ischemia, there were one limb with grade 2B and 4 with grade 3. Amputation of the lower extremities was avoided except for 1 extremity in which arterial reconstruction was not achieved due to unexplained cardiac arrest during surgery. CONCLUSIONS: CLS enables early reperfusion of the injured limb and is effective as a TVS method for traumatic PAI with severe ischemia or soft tissue damage.

Risk Analysis and Clinical Outcomes in Chronic Limb-threatening Ischemia Patients with Surgical Site Infection after Distal Bypass.

BACKGROUND: A recent randomized control study showed that long-term outcomes after surgical revascularization were superior to those after endovascular treatment for cases with chronic limb-threatening ischemia (CLTI) with an appropriate single-segment great saphenous vein. However, surgical site infection (SSI) in CLTI cases after infrapoplital bypass also resulted in a prolonged hospital stay and poor outcomes, including graft disruption. The aim of the current study was to analyze risk factors for SSI in CLTI patients after distal bypass and to compare outcomes in patients with and without SSI. METHODS: A total of 515 cases that underwent distal bypass at a single center between 2009 and 2022 were analyzed retrospectively. Comparisons were made between patients with and without SSI after distal bypass. The primary end point was limb salvage after distal bypass. RESULTS: Of the 515 cases that underwent distal bypass, 79 (15%) had SSI. The risk factors for SSI were preoperative antibacterial drug use (P = 0.001), pedal bypass (P = 0.001), and prolonged operation time (≥150 min) (P = 0.010). The median hospital stay in SSI cases was longer than that in non-SSI cases (P < 0.001). Of 515 distal bypasses, 7 (1.3%) bypass grafts ruptured postoperatively due to SSI, and of these 7 cases, 6 ruptured during the day, 5 cases occurred within 1 month postoperatively, and 2 patients (29%) are alive without amputation. The mean follow-up period was 34 ± 30 months. During follow-up, 62 limbs (SSI cases, 19; non-SSI cases, 43) required major amputation and there were 234 deaths (SSI cases, 46; non-SSI cases, 188). The 1-, 3-, and 5-year limb salvage rates of 82%, 71%, and 62%, respectively, in SSI cases were significantly lower than those in non-SSI cases (P < 0.001). The 5-year survival rate of 29% in SSI cases showed a tendency to be lower than that in non-SSI cases (P = 0.058). CONCLUSIONS: The limb salvage rate in SSI cases was lower than in non-SSI cases after distal bypass. Graft rupture due to SSI occurred at a rate of 1.3% and resulted in poor outcomes in most cases. SSIs adversely affect outcomes and further study is needed to identify methods to avoid SSI following distal bypass.

Ocular Ischemic Syndrome and the Role of Carotid Artery Revascularization.

BACKGROUND: Ocular ischemic syndrome (OIS) is a rare presentation of atherosclerotic carotid artery stenosis that can result in permanent visual loss. This severely disabling syndrome remains under diagnosed and undertreated due to lack of awareness; especially since it requires expedited multidisciplinary care. The relevance of early diagnosis and treatment is increasing due to an increasing prevalence of cerebrovascular disease. METHODS: The long-term visual and cerebrovascular outcomes following intervention for nonarteritic OIS, remain poorly described and were the objective of this concise review. We conducted a PubMed search to include all English language publications (cohort studies and case reports) between 2002 and 2023. RESULTS: A total of 33 studies (479 patients) report the outcomes of treatment of OIS with carotid endarterectomy (CEA, 304 patients, 19 studies), and carotid artery stenting (CAS, 175 patients, 14 studies). Visual outcomes were improved or did not worsen in 447 patients (93.3%). No periprocedural stroke was reported. Worsening visual symptoms were rare (35 patients, 7.3%); they occurred in the immediate postoperative period secondary to ocular hypoperfusion (3 patients) and in the late postoperative period due to progression of systemic atherosclerotic disease. Symptomatic recurrence due to recurrent stenosis after CEA was reported in 1 patient (0.21%); this was managed successfully with CAS. None of these studies report the results of transcarotid artery revascularization, the long-term operative outcome or stroke rate. CONCLUSIONS: OIS remains to be an underdiagnosed condition. Early diagnosis and prompt treatment are crucial in reversal or stabilization of OIS symptoms. An expedited multidisciplinary approach between vascular surgery and ophthalmology services is necessary to facilitate timely treatment and optimize outcome. If diagnosed early, both CEA and CAS have been associated with visual improvement and prevention of progressive visual loss.

Acute aortic occlusion: A narrative review for emergency clinicians.

INTRODUCTION: Acute aortic occlusion (AAO) is a rare but serious condition associated with significant morbidity and mortality. OBJECTIVE: This review provides an emergency medicine focused evaluation of AAO, including presentation, assessment, and emergency department (ED) management based on current evidence. DISCUSSION: AAO refers to obstruction of blood flow through the aorta due to either thrombosis or embolism. This condition primarily affects older adults ages 60-70 with cardiovascular comorbidities and most commonly presents with signs and symptoms of acute limb ischemia, though the gastrointestinal tract, kidneys, and spinal cord may be affected. The first line imaging modality includes computed tomography angiography of the chest, abdomen, and pelvis. ED resuscitative management consists of avoiding extremes of blood pressure or heart rate, maintaining normal oxygen saturation and euvolemic status, anticoagulation with heparin, and pain control. Emergent consultation with the vascular surgery specialist is recommended to establish a plan for restoration of perfusion to ischemic tissues via endovascular or open techniques. High rates of baseline comorbidities present in the affected population as well as ischemic and reperfusion injuries place AAO patients at high risk for complications in an immediate and delayed fashion after surgical management. CONCLUSIONS: An understanding of AAO can assist emergency clinicians in diagnosing and managing this rare but devastating disease.

Acute Kidney Injury After Heart Transplantation: Risk Factors and Clinical Outcomes.

OBJECTIVE: Acute kidney injury (AKI) requiring renal-replacement therapy (RRT) after heart transplantation (OHT) is common and impairs outcomes. This study aimed to identify independent donor and recipient risk factors associated with RRT after OHT. DESIGN: A retrospective data analysis. SETTING: Data were collected from clinical routines in a maximum-care university hospital. PARTICIPANTS: Patients who underwent OHT. INTERVENTIONS: The authors retrospectively analyzed data from 264 patients who underwent OHT between 2012 and 2021; 189 patients were eligible and included in the final analysis. MEASUREMENTS AND MAIN RESULTS: The mean age was 48.0 ± 12.3 years, and 71.4% of patients were male. Ninety (47.6%) patients were on long-term mechanical circulatory support (lt-MCS). Posttransplant AKI with RRT occurred in 123 (65.1%) patients. In a multivariate analysis, preoperative body mass index >25 kg/m² (odds ratio [OR] 4.74, p < 0.001), elevated preoperative creatinine levels (OR for each mg/dL increase 3.44, p = 0.004), administration of red blood cell units during transplantation procedure (OR 2.31, p = 0.041) and ischemia time (OR for each hour increase 1.77, p = 0.004) were associated with a higher incidence of RRT. The use of renin-angiotensin-aldosterone system blockers before transplantation was associated with a reduced risk of RRT (OR 0.36, p = 0.013). The risk of mortality was 6.9-fold higher in patients who required RRT (hazard ratio 6.9, 95% CI: 2.1-22.6 p = 0.001). Previous lt-MCS, as well as donor parameters, were not associated with RRT after OHT. CONCLUSIONS: The implementation of guideline-directed medical therapy, weight reduction, minimizing ischemia time (ie, organ perfusion systems, workflow optimization), and comprehensive patient blood management potentially influences renal function and outcomes after OHT.

Changes in Glomerular Volume, Sclerosis, and Ischemia at 5 Years after Kidney Transplantation: Incidence and Correlation with Late Graft Failure.

SIGNIFICANCE STATEMENT: Glomerular volume, ischemic glomeruli, and global glomerulosclerosis are not consistently assessed on kidney transplant biopsies. The authors evaluated morphometric measures of glomerular volume, the percentage of global glomerulosclerosis, and the percentage of ischemic glomeruli and assessed changes in these measures over time to determine whether such changes predict late allograft failure. All three features increased from transplant to five-year biopsy. Kidneys with smaller glomeruli at 5 years had more global glomerulosclerosis and a higher percentage of ischemic-appearing glomeruli. Smaller glomeruli and increasing percentages of global glomerulosclerosis and ischemic glomeruli at 5 years predicted allograft failure. Only increased percentage of ischemic glomeruli predicted allograft failure at 5 years independent of all Banff scores. Glomerular changes reflect pathologic processes that predicted allograft loss; measuring them quantitatively might enhance the current Banff system and provide biomarkers for intervention trials. BACKGROUND: Histology can provide insight into the biology of renal allograft loss. However, studies are lacking that use quantitative morphometry to simultaneously assess changes in mean glomerular volume and in the percentages of globally sclerosed glomeruli (GSG) and ischemic-appearing glomeruli in surveillance biopsies over time to determine whether such changes are correlated with late graft failure. METHODS: We used digital scans of surveillance biopsies (at implantation and at 1 and 5 years after transplantation) to morphometrically quantify glomerular volume and the percentages of GSG and ischemic-appearing glomeruli in a cohort of 835 kidney transplants. Cox proportional hazards models assessed the risk of allograft failure with these three glomerular features. RESULTS: From implantation to 5 years, mean glomerular volume increased by nearly 30% (from 2.8×10 6 to 3.6×10 6 µm 3 ), mean percentage of GSG increased from 3.2% to 13.2%, and mean percentage of ischemic-appearing glomeruli increased from 0.8% to 9.5%. Higher percentages of GSG and ischemic-appearing glomeruli at 5-year biopsy predicted allograft loss. The three glomerular features at 5-year biopsy were related; the percentage of GSG and the percentage of ischemic glomeruli were positively correlated, and both were inversely correlated to glomerular volume. At 5 years, only 5.3% of biopsies had ≥40% ischemic glomeruli, but 45% of these grafts failed (versus 11.6% for <40% ischemic glomeruli). Higher Banff scores were more common with increasing percentages of GSG and ischemia, but at 5 years, only the percentage of ischemic glomeruli added to predictive models adjusted for Banff scores. CONCLUSIONS: Glomerular changes reflect important pathologic processes that predict graft loss. Measuring glomerular changes quantitatively on surveillance biopsies, especially the proportion of ischemic-appearing glomeruli, may enhance the current Banff system and be a useful surrogate end point for clinical intervention trials. PODCAST: This article contains a podcast at.