Scaling of soil organic carbon in space and time in the Southern Coastal Plain, USA.

Soil organic carbon (SOC) is a dynamic soil property (DSP) that represents the largest portion of terrestrial carbon. Its relevance to carbon sequestration and the potential effects of land use on SOC storage, make it imperative to map across both space and time. Most regional-scale studies mapping SOC give static estimates and train different models for different periods with varying accuracies. We developed a flexible modeling approach called DSP-Scale to map SOC in both space and time. DSP-Scale uses ecological concepts and empirical data to predict DSP dynamics using inherent soil properties (static factors) and land cover changes (dynamic factors). We compiled SOC20 data from 1441 points spanning a 25 million ha study area in the southeastern U.S. Coastal Plain, incorporating data from the Rapid Carbon Assessment, National Cooperative Soil Survey Soil Characterization database, and other regional studies. We developed a random forest model using climate, topography, soil survey, and land cover changes to predict SOC20 dynamics for five-year periods between 2001 and 2019. Our model explained 66 % and 59 % of the variation for the training and test data, respectively. Top predictors included mean annual precipitation, slope, and soil erosion class. Land cover 10 years before measurements of SOC20 was more important than current land cover for estimating SOC20. We estimated total SOC stocks of 207.1 and 208.3 Tg for 2001 and 2019, respectively. Highest gains of total SOC stock (0.9 Tg from 2001 to 2019) were associated with land cover change from mixed to evergreen forest. The greatest loss of total SOC stock (0.2 Tg) in the same period was associated with land cover change from pasture/hay to evergreen forest. We concluded that the DSP-Scale approach provides a flexible way to use dynamic and static factors affecting SOC stocks to predict changes in space and time at regional scales.

Alternative Conduits for Lower Extremity Bypass.

While single-segment great saphenous vein (GSV) remains the gold-standard conduit for infrainguinal bypass, several alternative options are available for use when GSV is absent in patients with chronic limb threatening ischemia requiring infrainguinal revascularization including alternative autologous vein, prosthetic conduits, and cryopreserved vein grafts.

Agave distribution and floral display influence foraging rates of an endangered pollinating bat and implications for conservation.

Wildlife conservation involves making management decisions with incomplete knowledge of ecological relationships. Efforts to augment foraging resources for the endangered Mexican long-nosed bat (Leptonycteris nivalis) are progressing despite limited knowledge about the species' foraging behavior and requirements. This study aimed to understand L. nivalis responses to floral resource availability, focusing on individual agave- and local-scale characteristics influencing visitation rates to flowering agaves. We observed bat visitation at 62 flowering agaves around two roosts in northeast Mexico on 46 nights in the summers of 2017 and 2018. We found visitation rate had positive relationships with two agave-scale characteristics: the number of umbels with open flowers and the lower vertical position on the stalk of those umbels (i.e., earlier phenological stages of flowering). However, these factors exhibited strong negative interaction: with few umbels with open flowers, the position of flowering umbels had little effect on visitation rate, but when umbels with open flowers were abundant, visitation rate was more strongly related to the lower flowering umbel position. We also found relationships between visitation rate and two local-scale characteristics: negative for the density of flowering conspecifics within 30 m of the focal agave and positive for the density of dead standing agave stalks within 30 m. Our findings suggest opportunities to augment foraging resources for L. nivalis in ways that are consistent with their foraging behavior, including: increasing the supply of simultaneously blooming flowers by planting agave species that tend to have more umbels with simultaneously open flowers; planting multiple species of agaves with different flowering times to increase the availability of agaves with open flowers on lower-positioned umbels throughout the period when bats are present in the region; planting agaves in clusters; and keeping dead standing agave stalks on the landscape. Our study points to useful management strategies that can be implemented and monitored as part of an adaptive management approach to aid in conservation efforts.

Naturally segregating genetic variants contribute to thermal tolerance in a Drosophila melanogaster model system.

Thermal tolerance is a fundamental physiological complex trait for survival in many species. For example, everyday tasks such as foraging, finding a mate, and avoiding predation are highly dependent on how well an organism can tolerate extreme temperatures. Understanding the general architecture of the natural variants within the genes that control this trait is of high importance if we want to better comprehend thermal physiology. Here, we take a multipronged approach to further dissect the genetic architecture that controls thermal tolerance in natural populations using the Drosophila Synthetic Population Resource as a model system. First, we used quantitative genetics and Quantitative Trait Loci mapping to identify major effect regions within the genome that influences thermal tolerance, then integrated RNA-sequencing to identify differences in gene expression, and lastly, we used the RNAi system to (1) alter tissue-specific gene expression and (2) functionally validate our findings. This powerful integration of approaches not only allows for the identification of the genetic basis of thermal tolerance but also the physiology of thermal tolerance in a natural population, which ultimately elucidates thermal tolerance through a fitness-associated lens.

Assessing Time to Removal of Tunneled Dialysis Catheters after Arteriovenous Access Creation.

BACKGROUND: Tunneled dialysis catheters (TDCs) are a temporary bridge until definitive arteriovenous (AV) access is established. Our objective was to evaluate the time to TDC removal in patients who underwent AV access creations with TDCs already in place. METHODS: A single-center analysis of all AV access creations in patients with TDCs was performed (2014-2020). Primary outcome was time to TDC removal after access creation. RESULTS: There were 364 AV access creations with TDCs in place. The average age was 58 years, 44% of patients were female, and 64% were Black. The median time to TDC removal was 113 days (range, 22-931 days) with 71.4% having a TDC >90 days after access creation. Patients with TDC >90 days were often older (60 vs. 54.7), had hypertension (98.1% vs. 93.3%), were diabetic (65.4% vs. 47.1%), and had longer average time to maturation (107.1 vs. 55.4 days, P < 0.001) and first access (114 vs. 59.4 days, P < 0.001). Multivariable analysis showed that older age was associated with prolonged TDC placement (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.05, P = 0.005) and prosthetic graft use was associated with shorter TDC indwelling time (OR 0.09, 95% CI 0.04-0.23, P ≤ 0.001). Kaplan-Meier analysis showed that 87% of TDCs were removed at 1 year. CONCLUSIONS: The majority of patients with TDCs who underwent AV access creation had prolonged TDC placement. Prosthetic graft use was associated with shorter catheter times. Close follow-up after access placement, improving maturation times, and access type selection should be considered to shortened TDC times.

Long-term functional outcomes of upper extremity civilian vascular trauma.

OBJECTIVE: Civilian analyses of long-term outcomes of upper extremity vascular trauma (UEVT) are limited. Our goal was to evaluate the management of UEVT in the civilian trauma population and explore the long-term functional consequences. METHODS: A retrospective review and analysis was performed of patients with UEVT at an urban Level 1 trauma center (2001-2022). Management and long-term functional outcomes were analyzed. RESULTS: There were 150 patients with UEVT. Mean age was 34 years, and 85% were male. There were 42% Black and 27% White patients. Mechanism was penetrating in 79%, blunt in 20%, and multifactorial in 1%. Within penetrating trauma, mechanism was from firearms in 30% of cases. Of blunt injuries, 27% were secondary to falls, 13% motorcycle collisions, 13% motor vehicle collisions, and 3% crush injuries. Injuries were isolated arterial in 62%, isolated venous in 13%, and combined in 25% of cases. Isolated arterial injuries included brachial (34%), radial (27%), ulnar (27%), axillary (8%), and subclavian (4%). The majority of arterial injuries (92%) underwent open repair with autologous vein bypass (34%), followed by primary repair (32%), vein patch (6.6%), and prosthetic graft (3.3%). There were 23% that underwent fasciotomies, 68% of which were prophylactic. Two patients were managed with endovascular interventions; one underwent covered stent placement and the other embolization. Perioperative reintervention occurred in 12% of patients. Concomitant injuries included nerves (35%), bones (17%), and ligaments (16%). Intensive care unit admission was required in 45%, with mean intensive care unit length of stay 1.6 days. Mean hospital length of stay was 6.7 days. Major amputation and in-hospital mortality rates were 1.3% and 4.6% respectively. The majority (72%) had >6-month follow-up, with a median follow-up period of 197 days. Trauma readmissions occurred in 19%. Many patients experienced chronic pain (56%), as well as motor (54%) and sensory (61%) deficits. Additionally, 41% had difficulty with activities of daily living. Of previously employed patients (57%), 39% experienced a >6-month delay in returning to work. Most patients (82%) were discharged with opioids; of these, 16% were using opioids at 6 months. CONCLUSIONS: UEVT is associated with long-term functional impairments and opioid use. It is imperative to counsel patients prior to discharge and ensure appropriate follow-up and therapy.

Recent evaluation by nephrologists is associated with decreased incidence of tunneled dialysis catheter being used at the time of first arteriovenous access creation.

OBJECTIVE: Late primary care provider (PCP) or nephrologist evaluation of patients with progressive kidney disease may be associated with increased morbidity and mortality. Among patients undergoing initial arteriovenous (AV) access creation, we aimed to study the relationship of recent PCP and nephrologist evaluations with perioperative morbidity and mortality. METHODS: We performed a retrospective review of patients from 2014 to 2022 who underwent initial AV access creation at an urban, safety-net hospital. Univariable and multivariable analyses identified associations of PCP and nephrologist evaluations <1 year and <3 months before surgery, respectively, with hemodialysis initiation via tunneled dialysis catheters (TDCs), 90-day readmission, and 90-day mortality. RESULTS: Among 558 patients receiving initial AV access, mean age was 59.7 ± 14 years, 59% were female gender, and 60.6% were Black race. Recent PCP and nephrology evaluations occurred in 386 (69%) and 362 (65%) patients, respectively. On multivariable analysis, unemployed and uninsured statuses were associated with decreased likelihood of PCP evaluation (unemployment: odds ratio [OR], 0.51; 95% confidence interval [CI], 0.34-0.77; uninsured status: OR, 0.05; 95% CI, 0.01-0.45) and nephrologist evaluation (unemployment: OR, 0.63; 95% CI, 0.43-0.91; uninsured status: OR, 0.22; 95% CI, 0.06-0.83) (all P < .05). Social support was associated with increased likelihood of PCP evaluation (OR, 1.81; 95% CI, 1.07-3.08) (all P < .05). Hemodialysis was initiated with TDCs in 304 patients (55%). Older age (OR, 0.98; 95% CI, 0.96-0.99), obesity (OR, 0.38; 95% CI, 0.25-0.58), and nephrologist evaluation (OR, 0.12; 95% CI, 0.08-0.19) were independently associated with decreased hemodialysis initiation with TDCs in patients receiving an initial AV access (all P < .05). Ninety-day readmission occurred in 270 cases (48%). Cirrhosis (OR, 2.5; 95% CI, 1.03-6.03; P = .04), coronary artery disease (OR, 2.31; 95% CI, 1.5-3.57), prosthetic AV access (OR, 1.84; 95% CI, 1.04-3.26), and impaired ambulation (OR, 1.75; 95% CI, 1.15-2.66) were independently associated with increased readmission (all P < .05). Older age (OR, 0.98; 95% CI, 0.97-0.99), prior TDC (OR, 0.65; 95% CI, 0.45-0.94), and unemployment (OR, 0.58; 95% CI, 0.39-0.86) were associated with decreased readmission (all P < .05). Ninety-day mortality occurred in 1.6% of patients. Neither PCP nor nephrologist evaluation was associated with readmission or mortality. CONCLUSIONS: Recent nephrology evaluation was associated with reduced hemodialysis initiation with TDCs among patients undergoing initial AV access creation. Unemployed and uninsured statuses posed barriers to accessing nephrology care.

Identifying inconsistencies in exotic pet regulations that perpetuate trade in risky species.

Regulatory inconsistencies at different jurisdictional levels have contributed to the global expansion of the exotic pet trade, with resultant increases in the spread of invasive species and pathogens. Researchers have enumerated multiple limitations and environmental risks posed by international and national rules that govern the exotic pet trade, yet little attention has focused on the regulation of the exotic pet trade within national borders. We reviewed state-level regulations that apply to the trade of vertebrate animal taxa in the United States. Definitions and classifications for regulating different vertebrate taxa varied greatly across states, and the terms pet and companion animal were poorly defined and inconsistent across states. States implemented regulations that permit trade in exotic vertebrate pets that are banned from import into the United States owing to public health and conservation concerns. Once species have been imported into the United States, inconsistent internal regulations facilitate the movement of animals that pose substantial invasion and disease risks. Violations of state laws were typically listed as misdemeanors, and the median fine for violating state wildlife trade laws was $1000. Inconsistent and incomplete regulation of exotic vertebrate pets across state borders, in conjunction with limited penalties for violating regulations, has facilitated continued possession of exotic pets in states where these animals are banned. Based on our review of regulatory weaknesses, we conclude that a transition to a federally enforced list of vertebrate species that may be traded as pets is needed, with all other vertebrate species banned from the exotic pet trade unless their potential invasion and disease risks have been assessed and demonstrated to be low or nonexistent.

Identificación de las inconsistencias en las regulaciones de las mascotas exóticas que perpetúan el mercado de especies riesgosas Resumen Las inconsistencias regulatorias en diferentes niveles regulatorios han contribuido a la expansión mundial del mercado de mascotas exóticas, con un incremento resultante en la dispersión de especies invasoras y patógenos. Los investigadores han enumerado varias limitaciones y riesgos ambientales que representan las normas nacionales e internacionales que dictan el mercado de mascotas exóticas, pero se ha puesto poca atención en la regulación de este mercado dentro de las fronteras nacionales. Revisamos las regulaciones a nivel estatal que aplican al mercado de taxones de vertebrados en los Estados Unidos (EU). Entre los estados, las definiciones y clasificaciones para regular el mercado de los diferentes taxones de vertebrados variaron mucho y los términos mascota y animal de compañía contaban con definiciones deficientes e incoherentes. Los estados implementaron regulaciones que permiten el mercado de vertebrados como mascotas exóticas cuya importación está prohibida para los EU debido a cuestiones de salud pública y conservación. Una vez que las especies han sido importadas a los EU, las regulaciones internas incoherentes facilitan el traslado de animales que representan un riesgo importante de invasión y de enfermedad. Con frecuencia, las violaciones a las leyes estatales se denominaban delitos menores y la multa promedio por violar las leyes estatales de comercio de fauna era de $1,000. La regulación incompleta e incoherente del mercado de mascotas exóticas entre los límites estatales, en conjunto con las penalizaciones limitadas por violar las regulaciones, ha facilitado la posesión continua de mascotas exóticas en estados en donde estos animales están prohibidos. Con base en nuestra revisión de las debilidades regulatorias, concluimos que se necesita transitar a una lista con aplicación federal de especies de vertebrados que pueden ser comercializadas como mascotas, con todas las demás especies de vertebrados vetadas del mercado a menos de que se haya evaluado su riesgo potencial de invasión y de enfermedad y se haya demostrado que es bajo o inexistente.

Outcomes of lower extremity revascularization in octogenarians and nonagenarians for intermittent claudication.

OBJECTIVE: Revascularization for intermittent claudication (IC) due to infrainguinal peripheral arterial disease (PAD) is dependent on durability and expected benefit. We aimed to assess outcomes for IC interventions in octogenarians and nonagenarians (age ≥80 years) and those younger than 80 years (age <80 years). METHODS: The Vascular Quality Initiative was queried (2010-2020) for peripheral vascular interventions (PVIs) and infrainguinal bypasses (IIBs) performed to treat IC. Baseline characteristics, procedural details, and outcomes were analyzed (comparing age ≥80 years and age <80 years). RESULTS: There were 84,210 PVIs (12.1% age ≥80 years and 87.9% age <80 years) and 10,980 IIBs (7.4% age ≥80 years and 92.6% age <80 years) for IC. For PVI, patients aged ≥80 years more often underwent femoropopliteal (70.7% vs 58.1%) and infrapopliteal (19% vs 9.3%) interventions, and less often iliac interventions (32.1% vs 48%) (P < .001 for all). Patients aged ≥80 years had more perioperative hematomas (3.5% vs 2.4%) and 30-day mortality (0.9% vs 0.4%) (P < .001). At 1-year post-intervention, the age ≥80 years cohort had fewer independently ambulatory patients (80% vs 91.5%; P < .001). Kaplan-Meier analysis showed patients aged ≥80 years had lower reintervention/amputation-free survival (81.4% vs 86.8%), amputation-free survival (87.1% vs 94.1%), and survival (92.3% vs 96.8%) (P < .001) at 1-year after PVI. Risk adjusted analysis showed that age ≥80 years was associated with higher reintervention/amputation/death (hazard ratio [HR], 1.22; 95% confidence interval [CI], 1.1-1.35), amputation/death (HR, 1.85; 95% CI, 1.61-2.13), and mortality (HR, 1.92; 95% CI, 1.66-2.23) (P < .001 for all) for PVI. For IIB, patients aged ≥80 years more often had an infrapopliteal target (28.4% vs 19.4%) and had higher 30-day mortality (1.3% vs 0.5%), renal failure (4.1% vs 2.2%), and cardiac complications (5.4% vs 3.1%) (P < .001). At 1 year, the age ≥80 years group had fewer independently ambulatory patients (81.7% vs 88.8%; P = .02). Kaplan-Meier analysis showed that the age ≥80 years cohort had lower reintervention/amputation-free survival (75.7% vs 81.5%), amputation-free survival (86.9% vs 93.9%), and survival (90.4% vs 96.5%) (P < .001 for all). Risk-adjusted analysis showed age ≥80 years was associated with higher amputation/death (HR, 1.68; 95% CI, 1.1-2.54; P = .015) and mortality (HR, 1.85; 95% CI, 1.16-2.93; P = .009), but not reintervention/amputation/death (HR, 1.1; 95% CI, 0.85-1.44; P = .47) after IIB. CONCLUSIONS: Octogenarians and nonagenarians have greater perioperative morbidity and long-term ambulatory impairment, limb loss, and mortality after PVI and IIB for claudication. Risks of intervention on elderly patients with claudication should be carefully weighed against the perceived benefits of revascularization. Medical and exercise therapy efforts should be maximized in this population.

Five Year Survival in Medicare Patients Undergoing Interventions for Peripheral Arterial Disease: a Retrospective Cohort Analysis of Linked Registry Claims Data.

OBJECTIVE: To justify the up front risks of offering elective interventions for intermittent claudication (IC), patients should have reasonable life expectancy to derive durable clinical benefits. Open surgery for chronic limb threatening ischaemia (CLTI) is maximally beneficial in patients surviving ≥ 2 years. The aim was to assess long term survival after IC and CLTI interventions. METHODS: In a retrospective cohort analysis, the Vascular Quality Initiative (VQI) registry from 1 January 2010 to 31 May 2021 was queried for peripheral vascular intervention (PVI), infra-inguinal bypasses (IIB), and supra-inguinal bypasses (SIB) for IC and CLTI across 286 US centres. VQI linkage to Medicare insurance claims provided five year survival data. Multivariable analysis identified factors associated with five year mortality. RESULTS: There were 31 457 PVIs (44.7% IC, 55.3% CLTI), 7 978 IIBs (26.9% IC, 73.1% CLTI), and 2 149 SIBs (50.1% IC, 49.9% CLTI) recorded in the VQI. Among the PVI, IIB, and SIB cohorts, average ages were 75, 73, and 72 years, respectively. Respective five year mortality after PVI for IC and CLTI was 37.2% and 71.1%; after IIB for IC and CLTI it was 37.8% and 60%; and after SIB for IC and CLTI it was 33.8% and 53.8%. On multivariable analysis, across all procedures, end stage renal disease, CLTI, congestive heart failure, anaemia, chronic obstructive pulmonary disease, and prior amputation were independently associated with increased mortality. Pre-admission home living and pre-operative aspirin use were independently associated with decreased mortality. CONCLUSION: Long term survival in Medicare patients undergoing interventions in VQI centres for peripheral arterial disease is poor. Two thirds of CLTI patients and over one third of IC patients were not alive at five years. Intervening for IC in patients with high mortality risk should be avoided. For CLTI patients identified with decreased survival likelihood, intervention durability may be less important than invasiveness. Pre-operative medical optimisation should always be undertaken.

Naturally segregating genetic variants contribute to thermal tolerance in a D. melanogaster model system.

Thermal tolerance is a fundamental physiological complex trait for survival in many species. For example, everyday tasks such as foraging, finding a mate, and avoiding predation, are highly dependent on how well an organism can tolerate extreme temperatures. Understanding the general architecture of the natural variants of the genes that control this trait is of high importance if we want to better comprehend how this trait evolves in natural populations. Here, we take a multipronged approach to further dissect the genetic architecture that controls thermal tolerance in natural populations using the Drosophila Synthetic Population Resource (DSPR) as a model system. First, we used quantitative genetics and Quantitative Trait Loci (QTL) mapping to identify major effect regions within the genome that influences thermal tolerance, then integrated RNA-sequencing to identify differences in gene expression, and lastly, we used the RNAi system to 1) alter tissue-specific gene expression and 2) functionally validate our findings. This powerful integration of approaches not only allows for the identification of the genetic basis of thermal tolerance but also the physiology of thermal tolerance in a natural population, which ultimately elucidates thermal tolerance through a fitness-associated lens.

Functional Impairment is Associated with Poor Long-Term Outcomes after Arteriovenous Access Creation.

BACKGROUND: Functional impairment affects outcomes after a variety of procedures. However, the impact of functional impairment on outcomes of arteriovenous (AV) access creation is unclear. We aimed to evaluate the association of patients' ability to ambulate and perform activities of daily living (ADL) with AV access outcomes. METHODS: We retrospectively reviewed patients undergoing AV access creation at an urban, safety-net hospital from 2014 to 2022. We evaluated associations of impaired ambulatory and assisted ADL status with 90-day readmission, 1-year primary patency, and 5-year mortality. RESULTS: Among the 689 patients receiving AV access, mean age was 59.6 ± 13.9 years, 59% were male, and 60% were Black. Access types included brachiocephalic (42%), brachiobasilic (26%), radiocephalic (14%), other autogenous (5%) fistulas, and prosthetic grafts (13%). Impaired ambulatory status was identified in 35% and assisted ADL status, when assessed, was identified in 21% of patients. Ninety-day readmission was more likely in patients with impaired ambulatory (58% vs. 39%, P < 0.001) and assisted ADL (56% vs. 41%, P = 0.004) status. On Kaplan-Meier analysis, 1-year primary patency was lower for patients with impaired ambulatory status (44% ± 3% vs. 29% ± 3%, P = 0.001), but was not significantly different for patients with assisted ADL status (41% ± 3% vs. 32% ± 5%, P = 0.12). Five-year survival was lower for patients with impaired ambulatory status (53% ± 5% vs. 74% ± 4%, P < 0.001), but was not significantly different for patients with assisted ADL status (45% ± 9% vs. 71% ± 4%, P = 0.1). On multivariable analysis, increased likelihood of 90-day readmission was significantly associated with impaired ambulatory status (odds ratio (OR) 2.03, 95% confidence interval (CI) 1.4-2.94, P < 0.001) and assisted ADL status (OR 1.66, 95% CI 1.07-2.57, P = 0.02). One-year primary patency was not significantly associated with impaired ambulatory (hazard ratio (HR) 1.25, 95% CI 0.98-1.6, P = 0.07) or assisted ADL status (HR 1.13, 95% CI 0.87-1.48, P = 0.36). Increased likelihood of 5-year mortality was associated with impaired ambulatory (HR 1.65, 95% CI 1.04-2.62, P = 0.04) and assisted ADL status (HR 2.63, 95% CI 1.35-5.11, P = 0.004). CONCLUSIONS: Impaired ambulatory and assisted ADL statuses were associated with increased readmissions and long-term mortality after AV access creation. Approximately half of patients with functional impairment were not alive at 5 years. Setting outcome expectations as well as prospectively examining the impact of physical therapy and visiting nursing services for functionally impaired patients undergoing AV access creation are warranted.

The Effect of Chronic and End-Stage Renal Disease on Long-Term Outcomes after Infrainguinal Bypass.

BACKGROUND: Patients undergoing infrainguinal bypass for chronic limb threatening ischemia (CLTI) with renal dysfunction are at an increased risk for perioperative and long-term morbidity and mortality. Our goal was to examine perioperative and 3-year outcomes after lower extremity bypass for CLTI stratified by kidney function. METHODS: A retrospective, single-center analysis of lower extremity bypass for CLTI was performed between 2008 and 2019. Kidney function was categorized as normal (estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2), chronic kidney disease (CKD) (eGFR 15-59 mL/min/1.73 m2), and end-stage renal disease (ESRD) (eGFR <15 mL/min/1.73 m2). Kaplan-Meier and multivariable analysis were performed. RESULTS: There were 221 infrainguinal bypasses performed for CLTI. Patients were classified by renal function as normal (59.7%), CKD (24.4%), and ESRD (15.8%). Average age was 66 years and 65% were male. Overall, 77% had tissue loss with 9%, 45%, 24%, and 22% being Wound, Ischemia, and foot Infection stages 1-4, respectively. The majority (58%) of bypass targets was infrapopliteal and 58% used ipsilateral greater saphenous vein. The 90-day mortality and readmission rates were 2.7% and 49.8%, respectively. ESRD, compared to CKD and normal renal function, respectively, had the highest 90-day mortality (11.4% vs. 1.9% vs. 0.8%, P = 0.002) and 90-day readmission (69% vs. 55% vs. 43%, P = 0.017). On multivariable analysis, ESRD, but not CKD, was associated with higher 90-day mortality (odds ratio (OR) 16.9, 95% confidence interval (CI) 1.83-156.6, P = 0.013) and 90-day readmission (OR 3.02, 95% CI 1.2-7.58, P = 0.019). Kaplan-Meier 3-year analysis showed no difference between groups for primary patency or major amputation; however, ESRD, compared to CKD and normal renal function, respectively, had worse primary-assisted patency (60% vs. 76% vs. 84%, P = 0.03) and survival (72% vs. 96% vs. 94%, P = 0.001). On multivariable analysis, ESRD and CKD were not associated with 3-year primary patency loss/death, but ESRD was associated with higher primary-assisted patency loss (hazard ratio (HR) 2.61, 95% CI 1.23-5.53, P = 0.012). ESRD and CKD were not associated with 3-year major amputation/death. ESRD was associated with higher 3-year mortality (HR 4.95, 95% CI 1.52-16.2, P = 0.008) while CKD was not. CONCLUSIONS: ESRD, but not CKD, was associated with higher perioperative and long-term mortality after lower extremity bypass for CLTI. Although ESRD was associated with lower long-term primary-assisted patency, there were no differences in loss of primary patency or major amputation.

Analysis of Early Death after Elective Open Abdominal Aortic Aneurysm Repair.

BACKGROUND: Mortality after open abdominal aortic aneurysm repair is a quality measure and early death may represent a technical complication or poor patient selection. Our objective was to analyze patients who died in the hospital within postoperative day (POD) 0-2 after elective abdominal aortic aneurysm repair. METHODS: The Vascular Quality Initiative was queried from 2003-2019 for elective open abdominal aortic aneurysm repairs. Operations were categorized as in-hospital death on POD 0-2 (POD 0-2 Death), in-hospital death beyond POD 2 (POD ≥3 Death), and those alive at discharge. Univariable and multivariable analyses were performed. RESULTS: There were 7,592 elective open abdominal aortic aneurysm repairs with 61 (0.8%) POD 0-2 Death, 156 (2.1%) POD ≥3 Death, and 7,375 (97.1%) alive at discharge. Overall, median age was 70 years and 73.6% were male. Iliac aneurysm repair and surgical approach (anterior/retroperitoneal) were similar among groups. POD 0-2 Death, compared to POD ≥3 Death and those alive at discharge, had the longest renal/visceral ischemia time, more commonly had proximal clamp placement above both renal arteries, an aortic distal anastomosis, longest operative time, and largest estimated blood loss (all P < 0.05). Postoperative vasopressor usage, myocardial infarction, stroke, and return to the operating room were most frequent in POD 0-2 Death and extubation in the operating room was least frequent (all P < 0.001). Postoperative bowel ischemia and renal failure occurred most commonly among POD ≥3 Death (all P < 0.001).On multivariable analysis, POD 0-2 Death was associated with congestive heart failure, prior peripheral vascular intervention, female sex, preoperative aspirin use, lower center volume quartile, renal/visceral ischemia time, estimated blood loss, and older age (all P < 0.05). CONCLUSIONS: POD 0-2 Death was associated with comorbidities, center volume, renal/visceral ischemia time, and estimated blood loss. Referral to high-volume aortic centers could improve outcomes.

Brachiocephalic and Radiocephalic Arteriovenous Fistulas in Patients with Tunneled Dialysis Catheters Have Similar Outcomes.

BACKGROUND: Patients with tunneled dialysis catheters (TDCs) have a time-sensitive need for a functional permanent access due to high risk of catheter-associated morbidity. Brachiocephalic arteriovenous fistulas (BCF) have been reported to have higher maturation and patency compared to radiocephalic arteriovenous fistulas (RCF), although more distal creation is encouraged when possible. However, this may lead to a delay in establishing permanent vascular access and, ultimately, TDC removal. Our goal was to assess short-term outcomes after BCF and RCF creation for patients with concurrent TDCs to see if these patients would potentially benefit more from an initial brachiocephalic access to minimize TDC dependence. METHODS: The Vascular Quality Initiative hemodialysis registry was analyzed from 2011 to 2018. Patient demographics, comorbidities, access type, and short-term outcomes including occlusion, reinterventions, and access being used for dialysis, were assessed. RESULTS: There were 2,359 patients with TDC, of whom 1,389 (58.9%) underwent BCF creation and 970 (41.1%) underwent RCF creation. Average patient age was 59 years, and 62.8% were male. Compared with RCF, those with BCF were more often older, of female sex, obese, nonindependently ambulatory, have commercial insurance, diabetes, coronary artery disease, chronic obstructive pulmonary disease, be on anticoagulation, and have a cephalic vein diameter of ≥3 mm (all P < 0.05). Kaplan-Meier analysis for 1-year outcomes for BCF and RCF, respectively, showed that primary patency was 45% vs. 41.3% (P = 0.88), primary assisted patency was 86.7% vs. 86.9% (P = 0.64), freedom from reintervention was 51.1% vs. 46.3% (P = 0.44), and survival was 81.3% vs. 84.9% (P = 0.02). Multivariable analysis showed that BCF was comparable to RCF with respect to primary patency loss (hazard ratio [HR] 1.11, 95% confidence interval [CI] 0.91-1.36, P = 0.316), primary assisted patency loss (HR 1.11, 95% CI 0.72-1.29, P = 0.66), and reintervention (HR 1.01, 95% CI 0.81-1.27, P = 0.92). Access being used at 3 months was similar but trending towards RCF being used more often (odds ratio 0.7, 95% CI 0.49-1, P = 0.05). CONCLUSIONS: BCFs do not have superior fistula maturation and patency compared to RCFs in patients with concurrent TDCs. Creation of radial access, when possible, does not prolong TDC dependence.

Postoperative disability and one-year outcomes for patients suffering a stroke after carotid endarterectomy.

OBJECTIVE: Although post-carotid endarterectomy (CEA) strokes are rare, they can be devastating. The degree of disability that patients develop after such events and its effects on long-term outcomes are unclear. Our goal was to assess the extent of postoperative disability in patients suffering strokes after CEA and evaluate its association with long-term outcomes. METHODS: The Vascular Quality Initiative CEA registry (2016-2020) was queried for CEAs performed for asymptomatic or symptomatic indications in patients with preoperative modified Rankin Scale (mRS) scores of 0 to 1. The mRS grades stroke-related disability as 0 (none), 1 (not significant), 2 to 3 (moderate), 4 to 5 (severe), and 6 (dead). Patients suffering postoperative strokes with recorded mRS scores were included. Postoperative stroke-related disability based on mRS and its association with long-term outcomes were analyzed. RESULTS: Among 149,285 patients undergoing CEA, there were 1178 patients without preoperative disability who had postoperative strokes and reported mRS scores. Mean age was 71 ± 9.2 years, and 59.6% of patients were male. Regarding ipsilateral cortical symptoms within 6 months preoperatively, 83.5% of patients were asymptomatic, 7.3% had transient ischemic attacks, and 9.2% had strokes. Postoperative stroke-related disability was classified as mRS 0 (11.6%), 1 (19.5%), 2 to 3 (29.4%), 4 to 5 (31.5%), and 6 (8%). One-year survival stratified by postoperative stroke-related disability was 91.4% for mRS 0, 95.6% for mRS 1, 92.1% for mRS 2 to 3, and 81.5% for mRS 4 to 5 (P < .001). Multivariable analysis demonstrated that while severe postoperative disability was associated with increased death at 1 year (hazard ratio [HR], 2.97; 95% confidence interval [CI], 1.5-5.89; P = .002), moderate postoperative disability had no such association (HR, 0.95; 95% CI, 0.45-2; P = .88). One-year freedom from subsequent ipsilateral neurological events or death stratified by postoperative stroke-related disability was 87.8% for mRS 0, 93.3% for mRS 1, 88.5% for mRS 2 to 3, and 77.9% for mRS 4 to 5 (P < .001). Severe postoperative disability was independently associated with increased ipsilateral neurological events or death at 1 year (HR, 2.34; 95% CI, 1.25-4.38; P = .01). However, moderate postoperative disability exhibited no such association (HR, 0.92; 95% CI, 0.46-1.82; P = .8). CONCLUSIONS: The majority of patients without preoperative disability who suffered strokes after CEA developed significant disability. Severe stroke-related disability was associated with higher 1-year mortality and subsequent neurological events. These data can improve informed consent for CEA and guide prognostication after postoperative strokes.

Variations in Practice Patterns for Peripheral Vascular Interventions Across Clinical Settings.

BACKGROUND: Peripheral vascular interventions (PVIs) for lower extremity peripheral artery disease have been increasing, particularly in the office-based setting. Our goal was to evaluate practice patterns for PVI by site of service using a contemporary real-world dataset. METHODS: The Vascular Quality Initiative PVI registry was queried from 2010-2021. Site of service was classified as hospital/inpatient, hospital/outpatient, and ambulatory/office-based center. Patient demographics, comorbidities, procedural details, and periprocedural outcomes were analyzed. RESULTS: There were 54,897 hospital/inpatient (43.2%), 64,105 hospital/outpatient (50.4%), and 8,179 ambulatory/office-based center (6.4%) PVI. When comparing the 2 outpatient settings, ambulatory/office-based center patients were older than hospital/outpatient (mean age 70.7 vs. 68.7 years), more often female sex (41.4% vs. 39.1%), never smokers (27.5% vs. 18.5%), primary Medicare (61.6% vs. 55.9%), nonambulatory (6.5% vs. 4.7%), less often with coronary artery disease (30.2% vs. 34.1%), chronic obstructive pulmonary disease (18.1% vs. 26.9%), congestive heart failure (13% vs. 17.2%), obesity (30.9% vs. 33.6%), and less often on a statin (71.4% vs. 76.1%) (P < 0.001). Ambulatory/office-based center procedures were more likely for claudication (60.1% vs. 55.8%), more often involved femoro-popliteal (73.1% vs. 64.6%) and infrapopliteal (36.7% vs. 24.3%), and less often iliac interventions (24.1% vs. 33.6%) (P < 0.001).Overall, atherectomy was used in 14.2% of hospital/inpatient, 19.4% of hospital/outpatient, and 63.4% of ambulatory/office-based center procedures. Stents were used in 41.8% of hospital/inpatient, 45.1% of hospital/outpatient, and 48.8% of ambulatory/office-based center procedures. However, stent grafts were used in 12.5% of hospital/inpatient, 8.8% of hospital/outpatient, and only 1.3% of ambulatory/office-based center procedures. On multivariable analysis, compared with hospital/inpatient, atherectomy use was associated with ambulatory/office-based center setting (Odds ratio 10.9, 95% confidence interval 10.3-11.5, P < 0.001) and hospital/outpatient setting (Odds ratio 1.57, 95% confidence interval 1.51-1.62, P < 0.001). Periprocedure complications including hematoma requiring intervention (0.3%), any stenosis/occlusion (0.2%), and distal embolization (0.6%) were quite low across all settings. CONCLUSIONS: There are substantial variations in patient populations, procedural indications, and types of interventions undertaken during PVI across different locations. Ambulatory/office-based procedures more commonly treat claudicants, use atherectomy, and less often use stent grafts. Further research is warranted to investigate long-term trends in practice patterns and long-term outcomes, for PVI in the ever-expanding ambulatory/office-based setting.

Qualitative Analysis of Length of Stay and Readmission after Carotid Endarterectomy.

BACKGROUND: Length of stay (LOS) and readmissions are common measures to evaluate quality of health care. The objective of this study was to evaluate factors related to hospital LOS and readmission within 90 days following carotid endarterectomy (CEA) in patients who have not had a stroke. METHODS: Using a single institution database, patients who underwent CEA for carotid stenosis between 2014 and 2019 were identified. Asymptomatic carotid stenosis (no history of any stroke or transient ischemic attack (TIA) within 6 months prior to CEA), and patients who had a TIA without stroke were included. Demographic and perioperative factors were collected. Primary outcomes analyzed were increased LOS (>1 day) and readmission within 90 days after surgery. RESULTS: There were 125 patients identified who underwent CEA for 133 carotid stenosis, and 8 patients had bilateral CEA; of which 36.8% were asymptomatic carotid stenosis with the remaining being operated on for TIA without any stroke. The mean age was 68 years old and 36.1% of cases were female. The median postoperative LOS was 2 days. Increased LOS occurred in 81 cases (60.9%). Increased LOS, compared to no increased LOS, occurred more often in patients with diabetes (48.1% vs. 30.8%, P = 0.047), in those with operations starting after 12:00 pm (45.7% vs. 21.2%, P = 0.004) and those with any minor complications such as neck swelling, neck pain, and urinary retention (30.9% vs. 15.4%, P = 0.044). Readmission within 90 days after CEA occurred in 24 (18%) of cases. Readmission within 90 days, compared to no readmission within 90 days, occurred more often in patients with a history of coronary artery disease (58.3% vs. 27.5%, P = 0.004), congestive heart failure (37.5% vs. 11%, P = 0.001), and atrial fibrillation (29.2% vs. 8.3%, P = 0.004). CONCLUSIONS: More than half of patients undergoing CEA for carotid stenosis were discharged after postoperative day 1. Interventions on modifiable clinical risk factors, such as morning CEA scheduling and management of comorbidities, may decrease LOS and 90-day readmission rates.

Hemodialysis Access Outcomes for Patients with Unstable Housing.

BACKGROUND: End-stage renal disease has traditionally been noted to disproportionately affect patients with fewer resources. Our goal was to assess practice patterns and outcomes in patients with unstable housing undergoing permanent hemodialysis access creation. STUDY DESIGN: A retrospective, single-center review of patients with unstable housing was conducted. Perioperative and long-term outcomes were assessed. Univariable and multivariable analysis as well as Kaplan-Meier analysis were performed. RESULTS: There were 144 patients (63% male) identified with a mean age of 57 years. Thirty-three percent of patients had no current permanent residence, and 81% had at least 3 addresses the year before operation. Access type included brachiocephalic (48%), brachiobasilic (19%), radiocephalic fistulas (11%), and prosthetic grafts (19%). Thirty-day readmission was seen in 27.8% of patients. Kaplan-Meier analysis showed that 1-year and 4-year patient survival were 94.4% and 80.6%, respectively. Multivariable analysis demonstrated that newly formed access (odds ratio [OR] 3.66, 95% CI 1.02 to 13.16, p = 0.05), absence of a permanent residence (OR 2.92, 95% CI 1.15 to 7.44, p = 0.03), and female gender (OR 2.86, 95% CI, 1.18 to 7.14, p = 0.02) were associated with 90-day readmission. Multivariable analysis of mortality revealed that previous stroke (hazard ratio [HR] 7.15, 95% CI 1.93 to 26.5, p = 0.003), history of alcohol use disorder (HR 4.55, 95% CI 1.22 to 16.99, p = 0.024), and age (HR 1.10, 95% CI, 1.02 to 1.18, p = 0.017) were associated with 4-year mortality; housing instability was not associated with decreased survival. Preoperative tunneled dialysis catheter (HR 1.63, 95% CI 1.02 to 2.61, p = 0.04) was associated with 4-year reintervention and frequent address change (HR 0.47, 95% CI 0.27 to 0.81, p = 0.01) was found to be a protective factor against long-term reintervention. CONCLUSION: Poor outcomes in patients with unstable housing were primarily driven by comorbidities. Lack of permanent residence was significantly associated with readmission.

A systematic review of routine post operative screening duplex ultrasound after thermal and non-thermal endovenous ablation.

OBJECTIVE: The Society of Vascular Surgery and the American Venous Forum recommend duplex ultrasound (DUS) following endovenous ablation. However, this screening may not be cost-effective or clinically indicated. The most common abnormal finding, endovenous heat-induced thrombosis (EHIT level 1-2), represents extension of thrombus from the saphenous <50% across the femoral or popliteal vein, which is thought to have a benign course regardless of intervention. The likelihood of venous thromboembolism (VTE) after thermal and non-thermal ablations was explored to determine the utility of routine postoperative DUS. METHODS: This is an updated and expanded systematic review including data from randomized trials and large observational studies (≥150 patients) of thermal and non-thermal ablations, examining the incidence of VTE. Using PubMed and EMBASE, 4584 publications were screened from 2000 through 2020. After applying inclusion and exclusion criteria, 72 studies were included. Random effects DerSimonian-Laird method was conducted to obtain the pooled incidence. We calculated the number of tests needed to detect one VTE, and the cost was derived from Center for Medicare Services tables. RESULTS: A total of 31,663 patients were included. The pooled incidence of EHIT II-IV, deep venous thrombosis (DVT), and pulmonary embolism (PE) was 1.32% (95% confidence interval [CI], 0.75%-2.02%); DVT (excluding EHIT), 0.20% (95% CI, 0.0%-0.2%); EHIT (I-IV), 2.51% (95% CI, 1.54%-3.68%); and EHIT (II-IV), 1.00% (95% CI, 0.51%-1.61%). There was no mortality. There was a lower DVT rate in thermal vs non-thermal ablations (0.23% vs 0.43%; P = .02); however, for all VTE (EHIT I-IV + DVT + PE), thermal techniques had more thrombosis (2.5% vs 0.5%; P <.001). When clinical significance is defined as DVT + EHIT (II-IV), 175 studies are needed to identify one VTE, costing $21,813 per "significant VTE." Patients receiving pharmacological prophylaxis had less EHIT I-IV compared with those who did not (3.04% vs 1.63%; P < .001); those who received DUS during the first post-op week had three times higher EHIT incidence compared with those whose first DUS was >7 days postoperative (6.6% vs 2.4%; P < .001). CONCLUSIONS: For thermal and non-thermal endovenous ablations, the incidence of VTE diagnosed with routine DUS is small and without clear clinical significance but caries a high cost. The Society of Vascular Surgery and the American Venous Forum recommendation to perform DUS within 72 hours is not justified by these data. We recommend a more targeted post-ablation scanning protocol including symptomatic patients and those at high risk.