Noncardiac Vascular Surgery Research Articles

Inflammatory Status as a Predictor of Perioperative Risk in Patients Undergoing Non-Cardiac Vascular Surgery

IntroductionPatients scheduled to undergo vascular surgery represent a significant population at risk of major adverse cardiac events (MACE’s) post operation. This is due to a number of inflammatory mechanisms, designed to aid in post surgical recovery. A number of screening tools have been designed such as the EAGLE risk score or the Goldman and Detsky scores, to aid in identification of at-risk individuals. Recently inflammatory biomarkers have been suggested as a tool to aid in this assessment. The role of interleukins such as IL-1 and Il-6 have particularly been of interest to current research. Our hypothesis aims to test whether there is any benefit to measuring inflammatory biomarkers post operation as a tool to identify individuals at risk of MACEs. MethodWe identified 75 eligible patients scheduled to undergo vascular surgery (bypass, EVAR or open AAA repair or endarterectomy) and measured four inflammatory biomarkers (IL-1, IL-6, ICAM-1 & CRP) pre and post operatively on days 1-4 to identify correlations and identify differences in individuals who had a MACE vs those that didn't. A MACE was defined by a rise in T troponin of 0.06 or greater or ECG changes agreed upon by two clinicians or a stroke ResultsOf the 75 patients, 13 were identified to have a MACE. The result showed that both IL-1 and ICAM show a significantly positive correlation between pre and post operative levels with ICAM-1 significantly positive on all 4 days and IL-1 significantly positive on days 1, 3 & 4. When comparing the significant difference in change in inflammatory biomarkers between the MACE group and non-MACE group, a significant difference was only noted in the ICAM biomarker. ICAM was significantly different between the two groups on day 1 and day 2 (t test value 0.0455 and 0.0492 respectively) but was non-significant on days 3 and 4. All other biomarkers showed no significant difference pre and post op. DiscussionOverall, it is suggestable that measuring inflammatory biomarkers in vascular surgery patients is a valuable aid to clinicians in potentially identifying at-risk groups and should be used as an adjunct to already existing mechanisms available to the clinician.

Perioperative transfusion study (PETS): Does a liberal transfusion protocol improve outcome in high-risk cardiovascular patients undergoing non-cardiac surgery? A randomised controlled pilot study.

Small studies have shown that patients with advanced coronary artery disease might benefit from a more liberal blood transfusion strategy. The goal of this pilot study was to test the feasibility of a blood transfusion intervention in a group of vascular surgery patients who have elevated cardiac troponins in rest. We conducted a single-centre, randomised controlled pilot study. Patients with a preoperative elevated high-sensitive troponin T undergoing non-cardiac vascular surgery were randomised between a liberal transfusion regime (haemoglobin >10.4 g/dL) and a restrictive transfusion regime (haemoglobin 8.0-9.6 g/dL) during the first 3 days after surgery. The primary outcome was defined as a composite endpoint of all-cause mortality, myocardial infarction or unscheduled coronary revascularization. In total 499 patients were screened; 92 were included and 50 patients were randomised. Postoperative haemoglobin was different between the intervention and control group; 10.6 versus 9.8, 10.4 versus 9.4, 10.9 versus 9.4 g/dL on day one, two and three respectively (p < 0.05). The primary outcome occurred in four patients (16%) in the liberal transfusion group and in two patients (8%) in control group. This pilot study shows that the studied transfusion protocol was able to create a clinically significant difference in perioperative haemoglobin levels. Randomisation was possible in 10% of the screened patients. A large definitive trial should be possible to provide evidence whether a liberal transfusion strategy could decrease the incidence of postoperative myocardial infarction in high risk surgical patients.

Perioperative hyperoxia- impact on myocardial biomarkers, strain and outcome in high-risk patients undergoing non-cardiac surgery: Protocol for a prospective randomized controlled trial

BackgroundSupplemental oxygen is used during every general anesthesia. However, for the maintenance phase of a general anesthesia, in most cases the longest part of anesthesia, only scarce evidence of dosing supplemental oxygen exists. Oxygen is a well-known coronary vasoconstrictor and thus may contribute to cardiovascular complications especially in vulnerable high-risk patients with coronary artery disease undergoing major non-cardiac surgery. Myocardial biomarkers are early indicators of myocardial injury. Oxygen supply demand mismatches due to coronary artery disease aggravated by hyperoxia might be displayed by changes from the biomarker's baseline-values. This study is designed to detect changes in myocardial biomarkers levels associated with perioperative hyperoxia. MethodsThis prospective randomized controlled interventional trial investigates the impact of maintaining perioperative high oxygen supplementation in high-risk patients undergoing non-cardiac vascular surgery on cardiac biomarkers, myocardial strain and outcome in 110 patients. Patients are allocated to be supplemented with either 0.3 (normal) or 0.8 (high) fraction of inspired oxygen (FiO2) perioperatively. Included is a short crossover phase during which transesophageal echocardiography is used to evaluate myocardial function at FiO2 0.3 and 0.8 by strain analysis in each patient. Patients will be followed up for complications at 30 days and 1 year. ConclusionThe trial is designed to evaluate perioperative changes from baseline myocardial biomarkers associated with perioperative FiO2. Furthermore, exploration and correlation of changes in biomarkers, acute early changes in myocardial function and clinical outcomes induced by different FiO2 may be possible.

Does Clopidogrel Reduce Major Adverse Cardiac Events in Patients Undergoing Non-Cardiac Vascular Surgery?

Does Clopidogrel Reduce Major Adverse Cardiac Events in Patients Undergoing Non-Cardiac Vascular Surgery?

Safety and efficacy of tranexamic acid in major non-cardiac vascular surgery: a systematic review and meta-analysis

Background: Tranexamic acid (TXA) is a synthetic lysine analogue that inhibits fibrinolysis. The effectiveness of TXA in obstetrics, trauma and orthopaedic and cardiac surgery is well established. However, concerns regarding its prothrombotic potential remain, which is an important consideration for vascular surgery. We aimed to evaluate the safety and efficacy of TXA in adults undergoing major non-cardiac vascular surgery. Methods: A pre-specified protocol (PROSPERO CRD42023427282) was followed. Relevant databases (PubMed, MEDLINE, EMBASE) were searched for randomised controlled trials (RCTs). Data extraction and risk of bias assessments were performed in duplicate. A random effects model was used to synthesise data from RCTs. Measures of effect were reported as relative risk (RR) with 95% confidence intervals (CIs). The primary safety outcome was a composite of arterial and venous thromboembolic events (composite of myocardial infarction, non-haemorrhagic stroke, peripheral arterial thrombosis and symptomatic proximal venous thromboembolism). Certainty of evidence was assessed using the GRADE approach. Results: After screening 1989 records, three RCTs were included, cumulatively enrolling 1,560 participants. In all trials, patients received either TXA (intravenously or orally) compared with placebo. There was no evidence of the effect of intravenous TXA on thromboembolic events (RR 1.10, 95% CI 0.89 to 1.36, two RCTs, 1460 participants, low certainty of evidence) or on critical bleeding (composite of life-threatening, critical and major organ bleed) (RR 0.85, 95% CI 0.65 to 1.11, two RCTs, 1460 participants, low certainty of evidence). TXA may reduce postoperative blood loss, especially at 0–4 hours (Cliff’s delta −0.41, 95% CI −0.19 to −0.59) and 0–24 hours (Cliff’s delta −0.37, 95% CI −0.14 to −0.55) after surgery. There was no evidence of an effect of TXA on reducing perioperative red blood cell (RBC) transfusion requirements (RR 0.66, 95% CI 0.11 to 3.95, one RCT, 100 participants). One RCT assessed oral TXA and found no evidence of an effect on type II endoleak post endovascular aneurysm repair. No thrombotic complications were reported in this RCT during the study period. Conclusions: We found no evidence of an effect of TXA on thromboembolic complications. While TXA appears to reduce early postoperative bleeding, the clinical relevance of this is uncertain. Due to limitations of study design and the variety of vascular procedures, the role of TXA in vascular surgery is still unclear. Ongoing trials may reduce this uncertainty. Registration: Prospectively registered on PROSPERO (CRD42023427282)

Nutritional status and out-of-hospital mortality in vascular surgery patients.

BackgroundMalnutrition is often present in vascular surgery patient during hospital admission. The present evidence of the consequence malnutrition has on morbidity and mortality is limited.AimThe purpose of this study was to determine the effect of nutritional status on out-of-hospital mortality in vascular surgery patients.MethodsAn observational cohort study was performed, studying non-cardiac vascular surgery patients surviving hospital admission 18 years or older treated in Boston, Massachusetts, USA. The exposure of interest was nutritional status categorized as well nourished, at-risk for malnutrition, nonspecific malnutrition or protein-energy malnutrition. The all cause 90-day mortality following hospital discharge was the primary outcome. Adjusted odds ratios were estimated by multivariable logistic regression models.ResultsThis cohort included 4432 patients comprised of 48% women and a mean age 61.7 years. After evaluation by a registered dietitian, 3819 patients were determined to be well nourished, 215 patients were at-risk for malnutrition, 351 had non-specific malnutrition and 47 patients had protein-energy malnutrition. After adjustment for age, sex, ethnicity, medical versus surgical Diagnosis Related Group type, Deyo-Charlson index, length of stay, and vascular Current Procedural Terminology code category, the 90-day post-discharge mortality odds ratio for patients with non-specific malnutrition OR 1.96 (95%CI 1.21, 3.17) and for protein-energy malnutrition OR 3.58 (95%CI 1.59, 8.06), all relative to patients without malnutrition.DiscussionNutritional status is a strong predictor of out-of-hospital mortality. This suggests that patient with vascular disease suffering from malnutrition could benefit from more intensified In-hospital and out-of-hospital dietary guidance and interventions.

Depletion of Homeostatic Antibodies against Malondialdehyde-Modified Low-Density Lipoprotein Correlates with Adverse Events in Major Vascular Surgery.

We aimed to investigate if major vascular surgery induces LDL oxidation, and whether circulating antibodies against malondialdehyde-modified LDL (MDA-LDL) alter dynamically in this setting. We also questioned relationships between these biomarkers and post-operative cardiovascular events. Major surgery can induce an oxidative stress response. However, the role of the humoral immune system in clearance of oxidized LDL following such an insult is unknown. Plasma samples were obtained from a prospective cohort of 131 patients undergoing major non-cardiac vascular surgery, with samples obtained preoperatively and at 24- and 72 h postoperatively. Enzyme-linked immunoassays were developed to assess MDA-LDL-related antibodies and complexes. Adverse events were myocardial infarction (primary outcome), and a composite of unstable angina, stroke and all-cause mortality (secondary outcome). MDA-LDL significantly increased at 24 h post-operatively (p < 0.0001). Conversely, levels of IgG and IgM anti-MDA-LDL, as well as IgG/IgM-MDA-LDL complexes and total IgG/IgM, were significantly lower at 24 h (each p < 0.0001). A smaller decrease in IgG anti-MDA-LDL related to combined clinical adverse events in a post hoc analysis, withstanding adjustment for age, sex, and total IgG (OR 0.13, 95% CI [0.03–0.5], p < 0.001; p value for trend <0.001). Major vascular surgery resulted in an increase in plasma MDA-LDL, in parallel with a decrease in antibody/complex levels, likely due to antibody binding and subsequent removal from the circulation. Our study provides novel insight into the role of the immune system during the oxidative stress of major surgery, and suggests a homeostatic clearance role for IgG antibodies, with greater reduction relating to downstream adverse events.

Functional Status and Out-of-Hospital Outcomes in Different Types of Vascular Surgery Patients

We aimed to determine the correlation between the functional status at discharge in non-cardiac vascular surgery patients and the out-of-hospital mortality. We performed a retrospective cohort study including adult non-cardiac vascular surgery patients (open, endovascular and venous procedures) surviving hospitalization in Boston, Massachusetts, USA. The exposure of interest was functional status determined by a licensed physical therapist at hospital discharge and rated based on qualitative categories adapted from the Functional Independence Measure. The primary outcome was all cause 90-day mortality after hospital discharge. The secondary outcome was readmission within 30days. Adjusted odds ratios were estimated by multivariable logistic regression models. This cohort included 2318 patients (male 51%; mean age 61 ± 17.7). After evaluation by a physiotherapist, 425 patients scored the lowest functional status, 631 scored moderately low, 681 moderately high and 581 scored the highest functional status. The lowest functional status was associated with a 3.41-fold increased adjusted odds for 90-day mortality (95%CI, 1.70-6.84) compared to patients with the highest functional status. When excluding venous intervention patients, the adjusted odds ratio was 6.76 (95%CI, 2.53-18.12) for the 90-day mortality post-discharge. The adjusted odds for readmission within 30-days was 1.5-fold increase in patients with the lowest functional status (95%CI, 1.04-2.20). In vascular surgery patients surviving hospitalization, functional status is strongly associated with out-of-hospital mortality and readmission rate. Future trials could provide evidence if improvement of functional status could prevent adverse outcomes in the postoperative setting.

Reply to the commentary on “Incidence, predictors and validation of risk scores to predict postoperative mortality after noncardiac vascular surgery, a prospective cohort study” [Int. J. Surg. 77 (2020) 181–2

Reply to the commentary on “Incidence, predictors and validation of risk scores to predict postoperative mortality after noncardiac vascular surgery, a prospective cohort study” [Int. J. Surg. 77 (2020) 181–2

Invited Commentary on "Incidence, predictors and validation of risk scores to predict postoperative mortality after noncardiac vascular surgery, a prospective cohort study".

Invited Commentary on "Incidence, predictors and validation of risk scores to predict postoperative mortality after noncardiac vascular surgery, a prospective cohort study".

Remote Ischaemic Preconditioning Attenuates Cardiac Biomarkers During Vascular Surgery: A Randomised Clinical Trial.

The main aim of this study was to evaluate the effect of remote ischaemic preconditioning (RIPC) on preventing the leakage of cardiac damage biomarkers in patients undergoing vascular surgery. This is a randomised, sham-controlled, double-blinded, single-centre study. Patients undergoing open abdominal aortic aneurysm repair, surgical lower limb revascularisation surgery or carotid endarterectomy were recruited non-consecutively. The RIPC protocol consisting of 4 cycles of 5 minutes of ischaemia, followed by 5 minutes of reperfusion, was applied. A RIPC or a sham procedure was performed noninvasively along with preparation for anaesthesia. High sensitivity troponin T level was measured preoperatively and 2, 8 and 24 hours after surgery and pro b-type natriuretic peptide was measured preoperatively and 24 hours after surgery. There was significantly higher leakage of high sensitivity troponin T (peak change median 2ng/L, IQR 0.9-6.2ng/L vs 0.6ng/L, IQR 0.7-2.1 ng/L, p=.0002) and pro b-type natriuretic peptide (change median 144pg/mL, IQR 17-318pg/mL vs 51pg/mL, IQR 12-196pg/mL, p=.02) in the sham group compared to the RIPC group. RIPC reduces the leakage of high sensitivity troponin T and pro b-type natriuretic peptide. Therefore, it may offer cardioprotection in patients undergoing non-cardiac vascular surgery. The clinical significance of RIPC has to be evaluated in larger studies excluding the factors known to influence its effect.

Red Cell Distribution Width at Hospital Discharge and Out-of Hospital Outcomes in Critically Ill Non-Cardiac Vascular Surgery Patients

Objective Red cell distribution width (RDW) is associated with mortality and bloodstream infection risk in the critically ill. In vascular surgery patients surviving critical care it is not known if RDW can predict subsequent risk of all-cause mortality following hospital discharge. We hypothesized that an increase in RDW at hospital discharge in vascular surgery patients who received critical care would be associated with increased mortality following hospital discharge. Design, setting, and participants We performed a two-center observational cohort study of critically ill non-cardiac vascular surgery patients surviving admission 18 years or older treated between November, 1997, and December 2012 in Boston, Massachusetts. Exposures RDW measured within 24 hours of hospital discharge and categorized a priori as ≤13.3%, 13.3-14.0%, 14.0-14.7%, 14.7-15.8%, >15.8%. Main outcomes and measures The primary outcome was all cause mortality in the 90 days following hospital discharge. Results The cohort included 4,715 patients (male 58%; white 83%; mean age 62.9 years). 90 and 365-day post discharge mortality was 7.5% and 14.4% respectively. In the cohort, 47.3% were discharged to a care facility and 14.8% of patients were readmitted within 30 days. After adjustment for age, gender, race, Deyo-Charlson comorbidity Index, patient type, acute organ failures, prior vascular surgery and vascular surgery category, patients with a discharge RDW 14.7-15.8% or >15.8% have an adjusted OR of 90-day post discharge mortality of 2.52 (95%CI, 1.29-4.90; P = 0.007) or 5.13 (95%CI, 2.70-9.75; P 15.8% group was 1.52 (95%CI, 1.12-2.07; P = 0.007) relative to patients with a discharge RDW ≤13.3%. Similar adjusted discharge RDW-outcome associations are present at 365 days following hospital discharge and for discharge to a care facility. Conclusions In critically ill vascular surgery patients who survive hospitalization, an elevated RDW at hospital discharge is a strong predictor of subsequent mortality, hospital readmission and placement in a care facility. Patients with elevated RDW are at high risk for adverse out of hospital outcomes and may benefit from closer post discharge follow-up and higher intensity rehabilitation.

Functional Status Measured at Hospital Discharge is Strongly Associated With Out-of-hospital Mortality and Re-admission in Non-cardiac Vascular Surgery Patients Surviving Admission

Introduction: Evaluation of the functional dependency of vascular surgery patients has proved to correlate with short-term mortality but lacks data in the long-term. The aim of this study was to determine the correlation between the functional status at discharge and the out-of-hospital mortality. Methods: We performed an observational cohort study including non-cardiac vascular surgery patients (open and endovascular) surviving hospital admission of 18 years or older in a tertiary care medical center. The exposure of interest was functional status determined by a licensed therapist at hospital discharge and rated based on qualitative categories adapted from the Functional Independence Measure. The primary outcome was all cause 90-day mortality after hospital discharge. Adjusted odds ratios were estimated by multivariable logistic regression models. Results: This cohort included 2318 patients (male 51%; mean age 61±17.7). After evaluation by a physiotherapist, 425 patients scored the lowest functional status, 631 scored moderately low, 681 patients moderately high and 581 patients scored the highest functional status. The unadjusted association of lowest functional status with 90-day mortality showed a 6.04-fold increase of odds (95% confidence interval(CI), 3.16-11.52) compared to patients with the highest functional status. After adjustement for age, gender, race, Deyo-Charlson index, patient type (surgical vs. medical), length of stay and vascular surgery type the association of lowest functional status with 90-day mortality was increased 3.41-fold (95% confidence interval(CI), 1.70-6.84) compared to patients with the highest functional status. When excluding patients who underwent venous interventions the adjusted odds ratio was 6.76 (95%CI, 2.53-18.12) for the 90-day mortality post-discharge. The odds for re-admission within 30-days was 1.5 fold increased in patients who scored the lowest functional status. Conclusion: In vascular surgery patients surviving admission, functional status is strongly associated with out-of-hospital mortality and readmission rate. This is especially apparent in patient who underwent an arterial vascular procedure. Ultimately, functional status could become a prevention target to improve the post-operative survival of vascular surgery patients by optimizing the functional status in the preoperative and postoperative setting. Disclosure: Nothing to disclose

Disease Activity in Takayasu’s Arteritis Affects Long-term Graft Related Outcomes

Introduction - Takayasu’s Arteritis (TA) is a rare, inflammatory large-vessel vasculitis of unknown etiology. This disease occasionally requires surgical intervention. There is a paucity of published data on the long-term outcomes of surgical intervention in these patients. There is limited data on the results of these procedures in patients with or without active disease. Methods - A retrospective review was conducted of patients with Takayasu’s arteritis who underwent open, noncardiac vascular procedures at our institution between 1994 and 2017. Basic demographics, diagnostic workup, treatment and outcomes were reviewed. Active disease was defined by the National Institute of Health or/and the Mayo Clinic criteria. Results - Between 1994 and 2017, 51 patients with Takayasu’s Arteritis underwent open noncardiac vascular surgery. Forty-four patients (86) were female with a mean age of 38 years (range 10-72 years). At the time of surgery 36 patients (77%) were on steroids, with 23 patients (49%) taking an additional immunomodulate pharmaceutical. Twenty patients (42%) had required prior vascular interventions. Six patients (13%) had an additional autoimmune disorder diagnosed previously. The most common location for disease was the aorta (86%) with the subclavian (80%), carotid (69%), innominate (41%), and the renal (33%) arterial lesions also seen. Vascular reconstruction was performed on 82 arterial lesions. The most common locations requiring reconstruction was the carotid artery (28%) followed by the subclavian (22%), aorta (15%) and renal arteries (11%). Mean follow-up was 74 months (range 1-265 months). Early complications (less than 30 days) occurred in 14 patients (31%). Late complications (greater than 31 days) occurred in 22 patients (49%). There were two perioperative mortalities (4%). Eighteen patients (40%) required endovascular and/or surgical reintervention. The primary and primary assisted patency were 72% and 89% respectively. Seventeen patients (35%) had active disease at the time of surgery and three (18%) of these patients developed graft occlusion and underwent revision. Six patients (35%) with active disease required eight additional graft related re-interventions. Thirty-one patients (65%) had quiescent disease with three (10%) of patients occluding their reconstruction follow-up. Four patients (13%) with quiescent disease required four additional graft related re-interventions. The incidence of graft related re-interventions was higher on patients with active disease (p<0.05). Erythrocyte sedimentation rate (ESR) demonstrates a sensitivity rate of 29% with a positive predictive valve of 63% in active disease. 71% of patients with active disease had a normal ESR. Conclusion - The outcome of the intervention appears to be related to the presence of active disease. Patients with active disease had worse graft related outcomes compared to patients with quiescent disease. Normalized ESR is not a good predictor of quiescent disease.

Mortality After Discharge in Non-cardiac Vascular Surgery Patients is Negatively Influenced by Malnutrition Measured at Hospital Discharge, Especially in Patients with Protein-Energy Malnutrition

Introduction: Vascular surgery patients have high rates of malnutrition during hospital admission. The effects of this nutrition status on morbidity and mortality in this population, especially after hospital discharge is not well documented. We sought to determine the impact of nutrition status on out-of-hospital mortality in vascular surgery patients. Methods: We performed an observational cohort study of non-cardiac vascular surgery patients surviving hospital admission 18 years or older treated in a tertiary care hospital. The exposure of interest was malnutrition categorized as nonspecific malnutrition, protein-energy malnutrition, or well nourished. This was determined by data related to anthropometric measurements, biochemical indicators, clinical signs of malnutrition, malnutrition risk factors, and metabolic stress. The primary outcome was all cause 90 day mortality after hospital discharge. Adjusted odds ratios were estimated by multivariable logistic regression models. Results: This cohort included 5561 patients (male 53%; mean age 60.1±17.2). The re-admission rate within 30 days was 13% and the mean length of stay was 6 days (IQR 2-13). After evaluation by a dietitian 4155 patients were well nourished, 475 patients were at-risk for malnutrition, 821 had non-specific malnutrition and 110 patients had protein-energy malnutrition. The unadjusted association between nutrition status and 90-day post-discharge mortality for patients with risk of malnutrition was 2.87 (95%CI 2.14,3.85); for non-specific malnutrition OR 4.41 (95%CI 3.54-5.49) and for protein-energy malnutrition OR 7.96 (95%CI 5.20-12.20), all relative to patients without malnutrition. After adjustment for age, gender, medical versus surgical patient type, type of vascular surgery, Deyo-Charlson index and length of stay, the 90-day post-discharge mortality odds ratio for patients with risk of malnutrition was 2.22 (95%CI, 1.61-3.06); for non-specific malnutrition OR 3.01 (95%CI 2.34-3.88) and for protein-energy malnutrition OR 3.53 (95%CI 2.22-5.63), all relative to patients without malnutrition. Conclusion: Nutrition status is a reliable indicator for out-of-hospital mortality. Intensified in-hospital and out-of-hospital dietary guidance and interventions could potentially improve the prognosis of patients after vascular surgery or endovascular intervention in the future. Disclosure: Nothing to disclose

Incidence, Predictors and Risk Scores to Predict Postoperative Mortality After Vascular Noncardiac Surgery

Incidence, Predictors and Risk Scores to Predict Postoperative Mortality After Vascular Noncardiac Surgery

External validation of the Revised Cardiac Risk Index and National Surgical Quality Improvement Program Myocardial Infarction and Cardiac Arrest calculator in noncardiac vascular surgery

BackgroundThe National Surgical Quality Improvement Program Myocardial Infarction & Cardiac Arrest (NSQIP MICA) calculator and the Revised Cardiac Risk Index (RCRI) were derived using currently outdated methods of diagnosing perioperative myocardial infarctions. We tested the external validity of these tools in a setting of a systematic perioperative cardiac biomarker measurement. MethodsAnalysis of routinely collected data nested in the Vascular Events In Noncardiac Surgery Patients Cohort Evaluation Study. A consecutive sample of patients ≥45 yr old undergoing in-hospital noncardiac surgery in a single tertiary care centre was enrolled. The predictive performance of the models was tested in terms of the occurrence of major cardiac complications defined as a composite of a nonfatal myocardial infarction, a nonfatal cardiac arrest, or a cardiac death within 30 days after surgery. The plasma concentration of high-sensitivity troponin T was measured before surgery, 6–12 h after operation, and on the first, second, and third days after surgery. Myocardial infarction was diagnosed according to the Third Universal Definition. ResultsThe median age was 65 (59–72) yr, and 704/870 (80.9%) subjects were male. The primary outcome occurred in 76/870 (8.7%; 95% confidence interval [CI], 6.9–10.8%) patients. The c-statistic was 0.64 (95% CI, 0.57–0.70) for the NSQIP MICA and 0.60 (95% CI, 0.54–0.65) for the RCRI. Predicted risks were systematically underestimated in calibration belts (P<0.001). The RCRI and the NSQIP MICA showed no clinical utility before recalibration. ConclusionsThe NSQIP and RCRI models had limited predictive performance in this at-risk population. The recently updated version of the RCRI was more reliable than the original index.

Eosinopenia and post-hospital outcomes in critically ill non-cardiac vascular surgery patients

Background and aimsEosinopenia is a marker for acute inflammation. We hypothesized that eosinopenia at Intensive Care Unit (ICU) admission in vascular surgery patients who receive critical care, would be associated with increased mortality following hospital discharge. Methods and resultsWe performed a two-center observational cohort study of critically ill, non-cardiac adult vascular surgery patients who received treatment in Boston between 1997 and 2012 and survived hospital admission. The consecutive sample included 5083 patients (male 57%, white 82%, mean age [SD] 61.6 [17.4] years). The exposure was Absolute eosinophil count measured within 24 h of admission to the ICU and categorized as ≤10 cells/μL, 11–50 cells/μL, 51–100 cells/μL, 101–350 cells/μL (normal range), and >350 cells/μL.The primary outcome was all-cause mortality within 90 days of hospital discharge. The secondary outcome was discharge to home following hospitalization. 90-day post-discharge mortality was 6.7%, and 12.9% of patients were readmitted within 30 days. After multivariable adjustment, patients with eosinopenia (≤10 cells/μL) have a 90-day post-discharge mortality OR of 1.97 (95%CI 1.42, 2.73; P < 0.001) relative to patients with an absolute eosinophil count of 101–350 cells/μL. Further, after multivariable adjustment, patients with eosinopenia (≤10 cells/μL) have a 25% lower odds of discharge to home compared to patients with an absolute eosinophil count of 101–350 cells/μL [OR = 0.71 (CI 95% 0.59–0.85); P < 0.001]. ConclusionEosinopenia at ICU admission is a robust predictor of increased mortality and lower likelihood of discharge to home in vascular surgery patients treated with critical care who survive hospitalization.

Major Cardiac Events in Patients Admitted to Intensive Care After Vascular Noncardiac Surgery: A Retrospective Cohort.

Introduction. Patients proposed to vascular noncardiac surgery (VS) have several comorbidities associated with major adverse cardiac events (MACE). We evaluated incidence, predictors, and outcomes, and compared different scores to predict MACE after VS. Methods. We included all patients admitted from 2006 to 2013. Perioperative MACE included cardiac arrhythmias, myocardial infarction (MI), cardiogenic pulmonary edema (CPE), acute heart failure (AHF), and cardiac arrest (CA). Lee Revised Cardiac Risk Index (RCRI), Vascular Quality Initiative (VQI-CRI), Vascular Study Group of New England (VSG-CRI), and South African Vascular Surgical (SAVS-CRI) Cardiac Risk Indexes were calculated and analyzed. We performed multivariate logistic regression to assess independent predictors with calculation of odds ratio (OR) and 95% confidence interval (CI). To reduce overfitting, we used leave-one-out cross-validation approach. The Predictive ability of scores was tested using area under receiver operating characteristic curve (AUROC). Results. A total of 928 patients were included. We observed 81 MACE (28 MI, 22 arrhythmias, 10 CPE, 9 AHF, 12 CA) in 60 patients (6.5%): 3.3% in intermediate-risk surgery and 9.8% in high-risk surgery. Previous history of coronary artery disease (OR = 3.2, CI = 1.8-5.7), atrial fibrillation (OR = 5.1, CI = 2.4-11.0), insulin-treated diabetes mellitus (OR = 3.26, CI = 1.51-7.06), mechanical ventilation (OR = 2.75, CI = 1.41-4.63), and heart rate (OR = 1.02, CI = 1.01-1.03) at admission were considered independent risk factors in multivariate analysis. The AUROC of our model was 0.79, compared with RCRI (0.66), VSG-CRI (0.69), VQI-CRI (0.71), and SAVS-CRI (0.73). Conclusions. Observed MACE were within predicted range (1% to 5% after intermediate-risk surgery and >5% after high-risk surgery). SAVS-CRI and VQI-CRI had slightly better predictive capacity than VSG-CRI or RCRI.

Red cell distribution width at hospital discharge and out-of hospital outcomes in critically ill non-cardiac vascular surgery patients

ObjectiveRed cell distribution width (RDW) is associated with mortality and bloodstream infection risk in the critically ill. In vascular surgery patients surviving critical care it is not known if RDW can predict subsequent risk of all-cause mortality following hospital discharge. We hypothesized that an increase in RDW at hospital discharge in vascular surgery patients who received critical care would be associated with increased mortality following hospital discharge.Design, setting, and participantsWe performed a two-center observational cohort study of critically ill non-cardiac vascular surgery patients surviving admission 18 years or older treated between November, 1997, and December 2012 in Boston, Massachusetts.ExposuresRDW measured within 24 hours of hospital discharge and categorized a priori as ≤13.3%, 13.3–14.0%, 14.0–14.7%, 14.7–15.8%, >15.8%.Main outcomes and measuresThe primary outcome was all cause mortality in the 90 days following hospital discharge.ResultsThe cohort included 4,715 patients (male 58%; white 83%; mean age 62.9 years). 90 and 365-day post discharge mortality was 7.5% and 14.4% respectively. In the cohort, 47.3% were discharged to a care facility and 14.8% of patients were readmitted within 30 days. After adjustment for age, gender, race, Deyo-Charlson comorbidity Index, patient type, acute organ failures, prior vascular surgery and vascular surgery category, patients with a discharge RDW 14.7–15.8% or >15.8% have an adjusted OR of 90-day post discharge mortality of 2.52 (95%CI, 1.29–4.90; P = 0.007) or 5.13 (95%CI, 2.70–9.75; P <0.001) relative to patients with a discharge RDW ≤13.3%. The adjusted odds of 30-day readmission in the RDW >15.8% group was 1.52 (95%CI, 1.12–2.07; P = 0.007) relative to patients with a discharge RDW ≤13.3%. Similar adjusted discharge RDW-outcome associations are present at 365 days following hospital discharge and for discharge to a care facility.ConclusionsIn critically ill vascular surgery patients who survive hospitalization, an elevated RDW at hospital discharge is a strong predictor of subsequent mortality, hospital readmission and placement in a care facility. Patients with elevated RDW are at high risk for adverse out of hospital outcomes and may benefit from closer post discharge follow-up and higher intensity rehabilitation.