Contemporary National Incidence and Outcomes of Acute Limb Ischemia.

BACKGROUND: Acute limb ischemia (ALI) is a morbid and deadly diagnosis. However, existing epidemiologic studies describing ALI predate the introduction of the Affordable Care Act in 2010 and direct oral anticoagulants in 2011. Thus, we synergized the National Inpatient Sample (NIS) and United States Census to define contemporary trends in the incidence, treatment, and outcomes of ALI in the US. METHODS: We included emergent admissions of adults with primary diagnosis of lower extremity ALI in survey-weighted NIS data (2005-2020). Mann-Kendal trend test evaluated ALI incidence (primary outcome), anticoagulation usage, insurance coverage, revascularization type, and in-hospital amputation/death. Multivariable logistic regression quantified covariate associations with in-hospital amputation/death. RESULTS: Of the 582,322,862 estimated hospitalizations in the NIS, 227,440 met the inclusion criteria (mean age 68.80 years, 49.94% women, 76.66% White). ALI incidence peaked in 2006 (7.16/100,000 person-years) but has declined since 2015 to 4.16/100,000 person-years in 2020 (ptrend = 0.008). Endovascular revascularization, anticoagulation, and Medicaid coverage increased, while self-pay insurance decreased (ptrend < 0.05). Amputation rates significantly decreased from 8.04 to 6.54% (ptrend = 0.01) while death rate remained at 5.59% (ptrend = 0.16) over the study period. Prehospitalization anticoagulation was associated with decreased amputation (adjusted odds ratio [aOR] = 0.74 (95% confidence interval [CI] 0.65-0.84)) and death (aOR = 0.50 (95% CI 0.43-0.57)). When controlling for covariates, women had a higher risk of death (aOR = 1.17 (95% CI 1.07-1.27), P < 0.0001), while Black patients had a higher risk of amputation (aOR = 1.24 (95% CI 1.10-1.41), P < 0.0001). CONCLUSIONS: Our US population based epidemiological study demonstrates that ALI incidence and in-hospital amputation rates are decreasing, while mortality remains unchanged. We further highlight the ongoing need for ALI investigation specifically as it relates to access to care, antithrombotic therapy use, treatment strategy, and strategies to combat gender and racial disparities.

The association between frailty and outcomes following ruptured abdominal aortic aneurysm repair.

OBJECTIVE: Endovascular aortic repair (EVAR) is a less invasive method than the more physiologically stressful open surgical repair (OSR) for patients with anatomically appropriate abdominal aortic aneurysms (AAAs). Early postoperative outcomes are associated with both patients; physiologic reserve and the physiologic stresses of the surgical intervention. Among frail patients with reduced physiologic reserve, the stress of an aortic rupture in combination with the stress of an operative repair are less well tolerated, raising the risk of complications and mortality. This study aims to evaluate the difference in association between frailty and outcomes among patients undergoing minimally invasive EVAR and the physiologically more stressful OSR for ruptured AAAs (rAAAs). METHODS: Our retrospective cohort study included adults undergoing rAAA repair in the Vascular Quality Initiative from 2010 to 2022. The validated Risk Analysis Index (RAI) (robust, ≤20; normal, 21-29; frail, 30-39; very frail, ≥40) quantified frailty. The association between the primary outcome of 1-year mortality and frailty status as well as repair type were compared using multivariable Cox models generating adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). Interaction terms evaluated the association's moderation. RESULTS: We identified 5806 patients (age, 72 ± 9 years; 77% male; EVAR, 65%; robust, 6%; normal, 48%; frail, 36%; very, frail 10%) with a 53% observed 1-year mortality rate following rAAA repair. OSR (aHR, 1.43; 95% CI, 1.19-1.73) was associated with increased 1-year mortality when compared with EVAR. Increasing frailty status (frail aHR, 1.26; 95% CI, 1.00-1.59; very frail aHR, 1.64; 95% CI, 1.26-2.13) was associated with increased 1-year mortality, which was moderated by repair type (P-interaction < .05). OSR was associated with increased 1-year mortality in normal (aHR, 1.49; 95% CI, 1.20-1.87) and frail (aHR, 1.51; 95% CI, 1.20-1.89), but not among robust (aHR, 0.88; 95% CI, 0.59-1.32) and very frail (aHR, 1.29; 95% CI, 0.97-1.72) patients. CONCLUSIONS: Frailty and OSR were associated with increased adjusted risk of 1-year mortality following rAAA repair. Among normal and frail patients, OSR was associated with an increased adjusted risk of 1-year mortality when compared with EVAR. However, there was no difference between OSR and EVAR among robust patients who can well tolerate the stress of OSR and among very frail patients who are unable to withstand the surgical stress from rAAA regardless of repair type.

Hypertension during transfer is associated with poor outcomes in unstable patients with ruptured abdominal aortic aneurysm.

OBJECTIVE: Limited data exist for optimal blood pressure (BP) management during transfer of patients with ruptured abdominal aortic aneurysm (rAAA). This study evaluates the effects of hypertension and severe hypotension during interhospital transfers in a cohort of patients with rAAA in hemorrhagic shock. METHODS: We performed a retrospective, single-institution review of patients with rAAA transferred via air ambulance to a quaternary referral center for repair (2003-2019). Vitals were recorded every 5 minutes in transit. Hypertension was defined as a systolic BP of ≥140 mm Hg. The primary cohort included patients with rAAA with hemorrhagic shock (≥1 episode of a systolic BP of <90 mm Hg) during transfer. The primary analysis compared those who experienced any hypertensive episode to those who did not. A secondary analysis evaluated those with either hypertension or severe hypotension <70 mm Hg. The primary outcome was 30-day mortality. RESULTS: Detailed BP data were available for 271 patients, of which 125 (46.1%) had evidence of hemorrhagic shock. The mean age was 74.2 ± 9.1 years, 93 (74.4%) were male, and the median total transport time from helicopter dispatch to arrival at the treatment facility was 65 minutes (interquartile range, 46-79 minutes). Among the cohort with shock, 26.4% (n = 33) had at least one episode of hypertension. There were no significant differences in age, sex, comorbidities, AAA repair type, AAA anatomic location, fluid resuscitation volume, blood transfusion volume, or vasopressor administration between the hypertensive and nonhypertensive groups. Patients with hypertension more frequently received prehospital antihypertensives (15% vs 2%; P = .01) and pain medication (64% vs 24%; P < .001), and had longer transit times (36.3 minutes vs 26.0 minutes; P = .006). Episodes of hypertension were associated with significantly increased 30-day mortality on multivariable logistic regression (adjusted odds ratio [aOR], 4.71; 95% confidence interval [CI], 1.54-14.39; P = .007; 59.4% [n = 19] vs 40.2% [n = 37]; P = .01). Severe hypotension (46%; n = 57) was also associated with higher 30-day mortality (aOR, 2.82; 95% CI, 1.27-6.28; P = .01; 60% [n = 34] vs 32% [n = 22]; P = .01). Those with either hypertension or severe hypotension (54%; n = 66) also had an increased odds of mortality (aOR, 2.95; 95% CI, 1.08-8.11; P = .04; 58% [n = 38] vs 31% [n = 18]; P < .01). Level of hypertension, BP fluctuation, and timing of hypertension were not significantly associated with mortality. CONCLUSIONS: Hypertensive and severely hypotensive episodes during interhospital transfer were independently associated with increased 30-day mortality in patients with rAAA with shock. Hypertension should be avoided in these patients, but permissive hypotension approaches should also maintain systolic BPs above 70 mm Hg whenever possible.

Transcriptomic and Proteomic Characterization of the Immune Response to Elective Spinal Reconstructive Surgery: Impact of Aging and Comparison with Traumatic Injury Response.

BACKGROUND: Major surgery triggers trauma-like stress responses linked to age, surgery duration, and blood loss, resembling polytrauma. This similarity suggests elective surgery as a surrogate model for studying polytrauma immune responses. We investigated stress responses across age groups and compared them with those of polytrauma patients. STUDY DESIGN: Patients undergoing major spinal reconstruction surgery were divided into older (age >65 years, n = 5) and young (age 18 to 39 years, n = 6) groups. A comparison group consisted of matched trauma patients (n = 8). Blood samples were collected before, during, and after surgery. Bone marrow mononuclear cells and peripheral blood mononuclear cells were analyzed using cellular indexing of transcriptomes and epitopes sequencing or single-cell RNA sequencing. Plasma was subjected to dual-platform proteomic analysis (SomaLogic and O-link). RESULTS: Response to polytrauma was highest within 4 hours. By comparison, the response to surgery was highest at 24 hours. Both insults triggered significant changes in cluster of differentiation 14 monocytes, with increased inflammation and lower major histocompatibility complex-class 2 expression. Older patient's cluster of differentiation 14 monocytes displayed higher inflammation and less major histocompatibility complex-class 2 suppression; a trend was also seen in bone marrow mononuclear cells. Although natural killer cells were markedly activated after polytrauma, they were suppressed after surgery, especially in older patients. In plasma, innate immunity proteins dominated at 24 hours, shifting to adaptive immunity proteins by 6 weeks with heightened inflammation in older patients. Senescence-associated secretory phenotype proteins were higher in older patients at baseline and further elevated during and after surgery. CONCLUSIONS: Although both major surgery and polytrauma initiate immune and stress responses, substantial differences exist in timing and cellular profiles, suggesting major elective surgery is not a suitable surrogate for the polytrauma response. Nonetheless, distinct responses in young vs older patients highlight the utility of elective spinal in studying patient-specific factors affecting outcomes after major elective surgery.

Characterization of multiple organ failure after ruptured abdominal aortic aneurysm repair.

BACKGROUND: Multiple organ failure (MOF) is associated with poor outcomes and increased mortality in sepsis and trauma. There are limited data regarding MOF in patients after ruptured abdominal aortic aneurysm (rAAA) repair. We aimed to identify the contemporary prevalence and characteristics of patients with rAAA with MOF. METHODS: We retrospectively reviewed patients with rAAA who underwent repair (2010-2020) at our multihospital institution. Patients who died within the first 2 days after repair were excluded. MOF was quantified by modified (excluding hepatic system) Denver, Sequential Organ Failure Assessment (SOFA) score, and Multiple Organ Dysfunction Score (MODS) for postoperative days 3 to 5 to determine the prevalence of MOF. MOF was defined as a Denver score of >3, dysfunction in two or more organ systems by SOFA score, or a MODS score of >8. Kaplan-Meier curves and log-rank testing were used to evaluate differences in 30-day mortality between multiple organ failure and patients without MOF. Logistic regression was used to assess predictors of MOF. RESULTS: Of 370 patients with rAAA, 288 survived past two days (mean age, 73±10.1 years; 76.7% male; 44.1% open repair), and 143 had data for MOF calculation recorded. From postoperative days 3 to 5, 41 (14.24%) had MOF by Denver, 26 (9.03%) by SOFA, and 39 (13.54%) by MODS criteria. Among these scoring systems, pulmonary and neurological systems were impacted most commonly. Among patients with MOF, pulmonary derangement occurred in 65.9% (Denver), 57.7% (SOFA), and 56.4% (MODS). Similarly, neurological derangement occurred in 92.3% (SOFA) and 89.7% (MODS), but renal derangement occurred in 26.8% (Denver), 23.1% (SOFA), and 10.3% (MODS). MOF by all three scoring systems was associated with increased 30-day mortality (Denver: 11.3% vs 41.5% [P < .01]; DOFA: 12.6% vs 46.2% [P < .01]; MODS: 12.5% vs 35.9% [P < .01]), as was MOF by any criteria (10.8% vs 35.7 %; P < .01). Patients with MOF were more likely to have a higher body mass index (55.9±26.6 vs 49.0±15.0; P = .011) and to have had a preoperative stroke (17.9% vs 6.0%; P = .016). Patients with MOF were less likely to have undergone endovascular repair (30.4% vs 62.1%; P < .001). Endovascular repair was protective against MOF (any criteria) on multivariate analysis (odds ratio, 0.23; 95% confidence interval, 0.08-0.64; P = .019) after adjusting for age, gender, and presenting systolic blood pressure. CONCLUSIONS: MOF occurred in only 9% to 14% of patients after rAAA repair, but was associated with a three-fold increase in mortality. Endovascular repair was associated with a reduced MOF incidence.

Selective Publication within Vascular Surgery: Characteristics of Discontinued and Unpublished Randomized Clinical Trials.

BACKGROUND: Discontinued and unpublished randomized clinical trials (RCTs) are common resulting in biased publication and loss of potential knowledge. The magnitude of selective publication within vascular surgery remains unknown. METHODS: RCT relevant to vascular surgery registered (01/01/2010-10/31/2019) on ClinicalTrials.gov were included. Trials ending normally with conclusion of participant treatment and examination were considered completed whereas discontinued trials stopped early. Publications were identified through automatically indexed PubMed citations on ClinicalTrials.gov or manually identified on PubMed or Google Scholar >30 months after the completion date, the date the final participant was examined, allowing time for publication. RESULTS: Of 108 RCT (n = 37, 837), 22.2% (24/108) were discontinued, including 16.7% (4/24) stopped prior to and 83.3% (20/24) after starting enrollment. Only 28.4% of estimated enrollment was achieved for all discontinued RCT. Nineteen (79.2%) investigators provided a reason for discontinuation, which most commonly included poor enrollment (45.8%), inadequate supplies or funding (12.5%), and trial design concerns (8.3%). Of the 20 trials terminated following enrollment, 20.0% (4/20) were published in peer-reviewed journals and 80.0% (16/20) failed to reach publication. Of the 77.8% trials completed, 75.0% (63/84) were published and 25.0% (21/84) remain unpublished. In a multivariate regression of completed trials, industry funding was significantly associated with decreased likelihood of peer-reviewed publication (OR = 0.18, (95% CI 0.05-0.71), P = 0.01). Of the discontinued and completed trials remaining unpublished, 62.5% and 61.9% failed to report results on ClinicalTrials.gov, respectively, encompassing a total of 4,788 enrollees without publicly available results. CONCLUSIONS: Nearly 25% of registered vascular RCT were discontinued. Of completed RCT, 25% remain unpublished with industry funding associated with decreased likelihood of publication. This study identifies opportunities to report all findings for completed and discontinued vascular surgery RCT, whether industry sponsored, or investigator initiated.

Adductor canal syndrome after lesser trochanter avulsion fracture in a 19-year-old.

A rare cause of limb ischemia in young patients, adductor canal syndrome, can be debilitating and result in functional impairment. Diagnosis and treatment may be delayed due to this vascular disease's rarity in young people and because the presenting symptoms can overlap with other more common causes of leg pain in young athletes. Here, authors discuss a young athletic patient with a history of year-long claudication. The patient's reported symptoms, exam findings, and imaging results were consistent with a diagnosis of adductor canal syndrome. This case proved uniquely challenging, given the extent of disease and illustrates potential approach considerations.

A Prospective Cohort Protocol for the Remnant Investigation in Sepsis Study.

BACKGROUND: Sepsis is a common and deadly syndrome, accounting for more than 11 million deaths annually. To mature a deeper understanding of the host and pathogen mechanisms contributing to poor outcomes in sepsis, and thereby possibly inform new therapeutic targets, sophisticated, and expensive biorepositories are typically required. We propose that remnant biospecimens are an alternative for mechanistic sepsis research, although the viability and scientific value of such remnants are unknown. METHODS AND RESULTS: The Remnant Biospecimen Investigation in Sepsis study is a prospective cohort study of 225 adults (age ≥ 18 yr) presenting to the emergency department with community sepsis, defined as sepsis-3 criteria within 6 hours of arrival. The primary objective was to determine the scientific value of a remnant biospecimen repository in sepsis linked to clinical phenotyping in the electronic health record. We will study candidate multiomic readouts of sepsis biology, governed by a conceptual model, and determine the precision, accuracy, integrity, and comparability of proteins, small molecules, lipids, and pathogen sequencing in remnant biospecimens compared with paired biospecimens obtained according to research protocols. Paired biospecimens will include plasma from sodium-heparin, EDTA, sodium fluoride, and citrate tubes. CONCLUSIONS: The study has received approval from the University of Pittsburgh Human Research Protection Office (Study 21120013). Recruitment began on October 25, 2022, with planned release of primary results anticipated in 2024. Results will be made available to the public, the funders, critical care societies, laboratory medicine scientists, and other researchers.

Epidemiology of age-, sex-, and race-specific hospitalizations for abdominal aortic aneurysms highlights gaps in current screening recommendations.

BACKGROUND: The detection and elective repair of abdominal aortic aneurysms (AAA) guided by known risk-factor specific screening decrease AAA-related mortality. However, minimal epidemiologic data exist for AAA in female persons and racial minority groups. We established the contemporary risk of US AAA hospitalization across age, sex, and race. METHODS: National Inpatient Sample and US Census (2012-2018) data were used to quantify age-, sex-, and race-specific incidences and adjusted odds ratios (aOR) of AAA hospitalizations (≥18 years), associated risk factors, and in-hospital mortality. Interaction terms evaluated subgroups. RESULTS: Among 1,728,374,183 US residents during the study period (51.3% female; 78.4% White, 12.7% Black, 5.7% Asian), 211,501,703 were hospitalized (aged 57.56 ± 0.04 years; 58.4% female; 64.9% White, 14.3% Black, 2.5% Asian) of which 291,850 were for AAA (aged 73.17 ± 0.04 years; 22.6% female; 81.8% White, 5.6% Black, 1.6% Asian). An estimated 15.2 (95% CI, 15.1-15.3) and 1.7 (95% CI, 1.7-1.7) hospitalizations per 100,000 residents were for intact AAA (iAAA) and ruptured AAA (rAAA) AAA, respectively. In addition, 16.2% of iAAA (83.8% male; 79.1% White) and 18.4% of rAAA (86.4% male; 75.0% White) hospitalizations occurred in patients less than 65 years of age. For iAAA, female sex (aOR, 0.27; 95% CI, 0.27-0.28) compared with male sex and both Black (0.47; 95% CI, 0.45-0.49) and Asian (0.86; 95% CI, 0.83-0.93) persons compared with White persons had a reduced aOR for hospitalization. For rAAA, the reduced aOR persisted for female sex (0.33; 95% CI, 0.32-0.36) and for Black persons (0.52; 95% CI, 0.46-0.58). Although female sex demonstrated an overall decreased odds of AAA hospitalization, female persons who were older, Black, or had peripheral vascular disease (Pinteractions < .001) had a relative increase in AAA hospitalization aOR. Female sex (aOR, 1.54; 95% CI, 1.38-1.70), but not Black or Asian race, was associated with increased mortality which was more pronounced for iAAA (1.93; 95% CI, 1.66-2.25) than rAAA (1.29; 95% CI, 1.13-1.48]; Pinteraction < .001). CONCLUSIONS: We confirmed a substantially decreased adjusted risk of AAA hospitalization for females and racial minority groups; however, aging and comorbid peripheral vascular disease decreased these differences. The disparate risk of AAA hospitalization by sex and race highlights the importance of inclusivity in future AAA studies.

Early Prehospital Tranexamic Acid Following Injury Is Associated With a 30-day Survival Benefit: A Secondary Analysis of a Randomized Clinical Trial.

OBJECTIVE: We sought to characterize the timing of administration of prehospital tranexamic acid (TXA) and associated outcome benefits. BACKGROUND: TXA has been shown to be safe in the prehospital setting post-injury. METHODS: We performed a secondary analysis of a recent prehospital randomized TXA clinical trial in injured patients. Those who received prehospital TXA within 1 hour (EARLY) from time of injury were compared to those who received prehospital TXA beyond 1 hour (DELAYED). We included patients with a shock index of >0.9. Primary outcome was 30-day mortality. Kaplan-Meier and Cox Hazard regression were utilized to characterize mortality relationships. RESULTS: EARLY and DELAYED patients had similar demographics, injury characteristics, and shock severity but DELAYED patients had greater prehospital resuscitation requirements and longer prehospital times. Stratified Kaplan-Meier analysis demonstrated significant separation for EARLY patients (N = 238, log-rank chi-square test, 4.99; P = 0.03) with no separation for DELAYED patients (N = 238, log-rank chi-square test, 0.04; P = 0.83). Stratified Cox Hazard regression verified, after controlling for confounders, that EARLY TXA was associated with a 65% lower independent hazard for 30-day mortality [hazard ratio (HR) 0.35, 95% confidence interval (CI) 0.19-0.65, P = 0.001] with no independent survival benefit found in DELAYED patients (HR 1.00, 95% CI 0.63-1.60, P = 0.999). EARLY TXA patients had lower incidence of multiple organ failure and 6-hour and 24-hour transfusion requirements compared to placebo. CONCLUSIONS: Administration of prehospital TXA within 1 hour from injury in patients at risk of hemorrhage is associated with 30-day survival benefit, lower incidence of multiple organ failure, and lower transfusion requirements.

Inferior Mid-term Durability with Comparable Survival for Younger Patients Undergoing Elective Endovascular Infrarenal versus Open Abdominal Aortic Aneurysm Repair.

BACKGROUND: The durability of endovascular aneurysm repair (EVAR) when compared to open surgical repair (OSR) in younger patients for elective, infrarenal abdominal aortic aneurysms (AAA) remains unclear due to limited follow-up. METHODS: We identified all patients <70 years of age who underwent elective, de novo EVAR or OSR for infrarenal AAA from 2003 to 2013 in a multihospital, single institution. Baseline patient clinical and aneurysmal characteristics were adjusted for using multivariable Cox proportional hazards models and negative binomial regression. RESULTS: We identified 253 patients: 204 underwent EVAR (80.6%) and 49 OSR (19.4%). Baseline demographics and comorbidities were similar across groups. There were no deaths in the immediate perioperative period. The rate of new arrhythmia (EVAR: 1.0%, OSR: 10.2%; P = 0.004), median hospital length of stay (EVAR: 1 day, OSR: 5 days; P < 0.001), and discharge to a facility (EVAR: 2.9%, OSR: 12.2%; P = 0.016) were significantly increased for OSR. In both groups, median follow-up time was 4.5 years, in which survival did not differ between groups. The hazard of composite of freedom from death and any reinterventions (hazard ratio [HR] 4.3, P = 0.009), freedom from any reintervention (relative risk [RR] 4.08, P = 0.030), and freedom from any endovascular reintervention (RR 4.83, P = 0.038) were each higher for OSR when compared to EVAR. EVAR of the standard instruction for use (IFU) for neck length was more likely to die or undergo a reintervention (HR 4.90, P = 0.001). CONCLUSIONS: Our retrospective review of younger patients undergoing elective AAA repair demonstrated no significant differences in perioperative mortality or survival over time between EVAR and OSR. EVAR required more total reinterventions and endovascular reintervention when compared to OSR.