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Enhanced Recovery After Surgery (ERAS) pathways have improved clinical outcomes, cost-effectiveness, and patient satisfaction across multiple non-cardiac surgical specialties. Since the adaptation of ERAS in cardiac surgery is rapidly increasing yet still evolving, herein, we demonstrate early results of our implementation of ERAS cardiac guidelines. We retrospectively reviewed all patients who were managed with our institutional ERAS Cardiac Surgery guidelines between 5/2018 and 6/2019(N = 102). Postoperative primary outcomes (total ventilation times(hours), intensive-care unit(ICU) stay, and postoperative hospital length of stay (LOS)) were compared to 1:1 propensity matched controls from the pre ERAS era between January 2017 and March 2019. A total of 76 propensity-matched pairs were identified. Compared to the matched controls, ERAS patients had significantly shorter median ventilation times(3.5 vs. 5.3 hours, p = .01), ICU stays(median 28 vs 48 hours, p=.005) and postoperative hospital LOS (median 5 vs. 6 days, p = .03). There were no operative mortalities and no significant differences in 30-day readmission rates. There were also no significant differences in post-operative stroke, acute kidney injury, atrial fibrillation, and reoperation rates for bleeding. Two-year survival was also not statistically different between the two cohorts (p = .22). Our initial experience with implementation of ERAS protocols in cardiac surgery appear to demonstrate that these protocols are associated with shorter ventilation times, ICU stay, and hospital LOS without compromising patient outcomes. While these results are promising yet preliminary, further studies are warranted to demonstrate whether ERAS algorithms in cardiac surgery can consistently expedite postoperative recovery and improve outcomes.

Mitral annular calcification (MAC) increases technical complexity for surgeons during mitral valve (MV) procedures. This study assesses the risks conferred by the presence of MAC in patients undergoing MV replacement (MVR) using The Society of Thoracic Surgeons Adult Cardiac Surgery Database.A total of 52,816 MVR procedures were performed between 2011 and June 2017. Individuals with concomitant tricuspid procedures were included, but those from institutions that reported1 MAC case/y were excluded. Operative mortality and in-hospital complications in MAC patients were compared with controls from the same institution. The contribution of hospital MV procedure volume (stratified by mean procedures per year during) to adjusted operative mortality was also assessed.Overall, 9551 MVR cases were classified as MAC (18.1%). Observed operative mortality was 5.8% for MAC and 4.4% for non-MAC patients (odds ratio [OR], 1.28; 95% confidence interval [CI], 1.19-1.38). Although postoperative stroke and reoperation rates were similar, MAC was associated with increased risk of acute kidney injury (relative risk, 1.15) and reintubation (relative risk, 1.26) (all P.001). After risk adjustment, MAC remained a risk factor for operative mortality (OR, 1.24; 95% CI, 1.08-1.42). Centers with less than 50 MV procedures/y were also associated with increased operative mortality (OR, 1.21; 95% CI, 1.08-1.37; observed-to-expected mortality among MAC patients 1.09 vs 0.82 in centers with ≥ 50 MV procedures; P = .001) CONCLUSIONS: The presence of MAC alone, regardless of severity, was independently associated with increased operative mortality and adverse postoperative outcomes. Even after adjusting for attendant cardiovascular and metabolic comorbidities, centers with low MV case volumes were found to have worse outcomes after MVR.

Interstitial lung disease (ILD) is a known risk factor for noncardiac surgery due to acute pulmonary exacerbations but its impact after cardiac surgery is not known. We examined perioperative outcomes and risk factors for long-term survival in ILD patients who underwent cardiac surgery. From January 2002 to June 2017, 294 cardiac surgery patients with a previous ILD diagnosis, including 75 patients with idiopathic pulmonary fibrosis (IPF), were identified. A comparison cohort of 1,481 non-ILD patients was selected based on a priori variables. Long-term survival was evaluated using Cox proportional hazard modeling. Median follow-up was 6.4 years. ILD patients had higher postoperative mortality, reintubation rates, longer intensive care unit stay, and higher 30-day readmission rates (all p

Background: We hypothesized that protein delivery during hospitalization in patients who survived critical care would be associated with outcomes following hospital discharge. Methods: We studied 801 patients, age &ge, 18 years, who received critical care between 2004 and 2012 and survived hospitalization. All patients underwent a registered dietitian formal assessment within 48 h of ICU admission. The exposure of interest, grams of protein per kilogram body weight delivered per day, was determined from all oral, enteral and parenteral sources for up to 28 days. Adjusted odds ratios for all cause 90-day post-discharge mortality were estimated by mixed- effects logistic regression models. Results: The 90-day post-discharge mortality was 13.9%. The mean nutrition delivery days recorded was 15. In a mixed-effect logistic regression model adjusted for age, gender, race, Deyo-Charlson comorbidity index, acute organ failures, sepsis and percent energy needs met, the 90-day post-discharge mortality rate was 17% (95% CI: 6&ndash, 26) lower for each 1 g/kg increase in daily protein delivery (OR = 0.83 (95% CI 0.74&ndash, 0.94, p = 0.002)). Conclusions: Adult medical ICU patients with improvements in daily protein intake during hospitalization who survive hospitalization have decreased odds of mortality in the 3 months following hospital discharge.

The association between nutritional status and mortality in critically ill patients is unclear based on the current literature. To clarify this relation, we analyzed the association between nutrition and mortality in a large population of critically ill patients and hypothesized that mortality would be impacted by nutritional status.Retrospective observational study.Single academic medical center.Six thousand five hundred eighteen adults treated in medical and surgical ICUs between 2004 and 2011.None.All cohort patients received a formal, in-person, standardized evaluation by a registered dietitian. The exposure of interest, malnutrition, was categorized as nonspecific malnutrition, protein-energy malnutrition, or well nourished and 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 30-day mortality determined by the Social Security Death Master File. Associations between nutrition groups and mortality were estimated by bivariable and multivariable logistic regression models. Adjusted odds ratios were estimated with inclusion of covariate terms thought to plausibly interact with both nutrition status and mortality. We used propensity score matching on baseline characteristics to reduce residual confounding of the nutrition status category assignment. In the cohort, nonspecific malnutrition was present in 56%, protein-energy malnutrition was present in 12%, and 32% were well nourished. The 30-day and 90-day mortality rates for the cohort were 19.1% and 26.6%, respectively. Nutritional status is a significant predictor of 30-day mortality following adjustment for age, gender, race, medical versus surgical patient type, Deyo-Charlson index, acute organ failure, vasopressor use, and sepsis: nonspecific malnutrition 30-day mortality odds ratio, 1.17 (95% CI, 1.01-1.37); protein-energy malnutrition 30-day mortality odds ratio, 2.10 (95% CI, 1.70-2.59), all relative to patients without malnutrition. In the matched cohort, the adjusted odds of 30-day mortality in the group of propensity score-matched patients with protein-energy malnutrition was two-fold greater than that of patients without malnutrition.In a large population of critically ill adults, an association exists between nutrition status and mortality.

Introduction Enhanced Recovery after Cardiac Surgery (ERACS) pathways can increase patient satisfaction, reduce the length of hospital stay and stay in the intensive care unit. The reported incidence of acute kidney injury (AKI) after cardiac surgery varies from 2.5% to 40% and is associated with an increased 30-day mortality¹. We examined the effect of ERACS on the total amount of fluid administered and the incidence of AKI. Methods We retrospectively analyzed prospectively collected outcome data of patients undergoing cardiac surgery enrolled in the ERAS pathway (n = 107) compared to a historical standard care group (n = 173). The ERAS pathway included pre-operative patient education, multimodal pain management to minimize opioid usage, carbohydrate loading 2-4hrs before induction of anesthesia, tight glucose control, early postoperative invasive access and chest tube removal, early extubation, and early mobilization. Intraoperatively, 500mL of the cardiopulmonary bypass (CBP) priming fluid was replaced with albumin 5% and the patients received 250mL albumin 5% before initiation and 250mL after separation from CBP. Crystalloid boli were administered in the intensie care unit (ICU) for clinical signs of hypovolemia, increasing pressor requirements or worsening metabolic acidosis. The standard care group was treated per preexisting institutional guidelines. AKI was defined using modified KDIGO (Kidney Disease Improving Global Outcomes) criteria, patients with pre-existing renal injury were excluded. Data were compared using univariate analysis: parametric and non-parametric data were analyzed with Student's t-test and Wilcoxon rank-sum test, respectively. A p-value of less than 0.05 was considered statistically significant. Results The mean (SD) creatinine pre-operatively, at discharge, and the peak creatinine were not different between the ERACS and the standard care group (table). Less fluid was administered in the ERACS group, but the total fluid balance was not different. No significant difference exists between the occurrence of AKI between those groups; no patient developed AKI worse than KDIGO stage 1 (modified). Discussion Although the ERACS patients received less fluid than the standard care group during the hospital stay, the incidence of AKI did not differ, nor did the serum creatinine at discharge between both groups. A restrictive fluid management with intraoperative albumin administration does not increase the incidence of acute kidney injury for patients in the ERACS pathway.

Pulmonary embolectomy is often indicated for central pulmonary embolism (PE) with hemodynamic instability, but remains controversial for hemodynamically stable patients with signs of right ventricular dysfunction. Because thrombolytic therapy is often contraindicated postoperatively, we reviewed risk factors and outcomes of pulmonary embolectomy for stable and unstable central PE, particularly in the early postoperative period.Between October 1999 and September 2013, 115 patients underwent pulmonary embolectomy for central, hemodynamically unstable PE (49 of 115, 43%) or hemodynamically stable PE (56 of 115, 49%). Ten operations for alternate indications (right atrial mass, endocarditis) were excluded for comparison analysis, leaving 105 patients.Mean age was 59 ± 13 years; 46 of 105 patients (44%) had recent surgery (within 5 weeks): orthopedic (12 of 46, 25%), neurosurgery (11 of 46, 24%), or general surgery (10 of 46, 22%). Preoperative demographics did not differ between groups, except for the frequency of cardiopulmonary resuscitation among unstable patients (11 of 49, 22%) versus stable patients (0 of 56, 0%; p0.001). Operative mortality for the combined groups was 6.6% (7 of 105): unstable 10.2% (5 of 49) versus stable 3.6% (2 of 56; p = 0.247). Of 11 patients requiring preoperative cardiopulmonary resuscitation, 4 died. Six-month, 1-year, and 3-year survival rates were, respectively, 75%, 68.4%, and 65.8% for unstable PE, and 92.6%, 86.7%, and 80.4% for stable PE (p = 0.018).This large series of pulmonary embolectomies demonstrates excellent early and late survival rates for patients with stable PE and unstable PE. These findings confirm pulmonary embolectomy as a beneficial therapeutic option for central PE, especially during the postoperative period when thrombolytic therapy is often contraindicated.

Catalytic iron, the chemical form of iron capable of participating in redox cycling, is a key mediator of acute kidney injury (AKI) in multiple animal models, but its role in human AKI has not been studied. Here we tested in a prospective cohort of 250 patients undergoing cardiac surgery whether plasma catalytic iron levels are elevated and associated with the composite outcome of AKI requiring renal replacement therapy or in-hospital mortality. Plasma catalytic iron, free hemoglobin, and other iron parameters were measured preoperatively, at the end of cardiopulmonary bypass, and on postoperative days 1 and 3. Plasma catalytic iron levels, but not other iron parameters, rose significantly at the end of cardiopulmonary bypass and were directly associated with bypass time and number of packed red blood cell transfusions. In multivariate analyses adjusting for age and preoperative eGFR, patients in the highest compared with the lowest quartile of catalytic iron on postoperative day 1 had a 6.71 greater odds of experiencing the primary outcome, and also had greater odds of AKI, hospital mortality, and postoperative myocardial injury. Thus, our data are consistent with and expand on findings from animal models demonstrating a pathologic role of catalytic iron in mediating adverse postoperative outcomes. Interventions aimed at reducing plasma catalytic iron levels as a strategy for preventing AKI in humans are warranted.

Background The association between long-term survival and aortic atheroma in cardiac surgical patients has not been comprehensively investigated. In this study we determine the relation between grade of atheroma and the risk of long-term mortality in a retrospective cohort of more than 20,000 patients undergoing cardiac operation during a 20-year period. Methods We included 22,304 consecutive intraoperative transesophageal and epiaortic ultrasound examinations performed at Brigham and Women's Hospital between 1995 and 2014, with long-term follow-up. The extent of atheromatous disease recorded in each examination was used for analysis. Mortality data were obtained from our institution's data registry. Mortality analyses were done using Cox proportional hazard regression models with follow-up as a time scale. We repeated the analysis in a subgroup of 14,728 patients with more detailed demographic characteristics, including postoperative stroke, queried from the institutional Society of Thoracic Surgeons database. Results A total of 7,722 mortality events and 872 stroke events occurred. Patients with atheromatous disease demonstrated a significant increase in mortality across all grades of severity, both for the ascending and descending aorta. This relation remained unchanged after adjusting for additional covariates. Adjustments for postoperative stroke resulted in only minimal attenuation in the risk of postoperative mortality related to aortic atheroma. Conclusions Aortic atheromatous disease of any grade in the ascending and descending aorta is a significant long-term risk of long-term, all-cause mortality in cardiac operation patients. This association remains independent of other conventional risk factors and is not related to postoperative cerebrovascular accidents.

Mitral valve repair for mitral regurgitation (MR) is currently recommended based on the degree of MR and left ventricular (LV) function. The present study examines predictors of reverse remodeling after repair for degenerative disease. We retrospectively identified 439 patients who underwent repair for myxomatous mitral valve degeneration and had both pre- and postoperative echocardiographic data available. Patients were categorized based on left atrial (LA) diameter and LV diameter standards of the American Society of Echocardiography. The outcome of interest was the degree of reverse remodeling on all heart dimensions at follow-up. Mean age was 57 ± 12 years, and 37% of patients were women. Mean preoperative LV end-diastolic diameter was 5.8 ± 0.7 cm, LV end-systolic diameter 3.5 ± 0.6 cm, LA 4.7 ± 0.7 cm, and median ejection fraction 60%. Median observation time was 81 months, and time to postoperative echocardiography was 38 months. Overall, 95% of patients had normal LV diastolic dimensions postoperatively, 93% normal LV systolic dimensions, and 37% normal LA dimensions. A Cox regression analysis showed that moderate (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.3 to 3.4) or severe preoperative LA dilatation (OR 2.7, 95% CI 1.7 to 4.4), abnormal preoperative LV end-systolic dimensions (OR 1.3, 95% CI 1.1 to 1.5), and age in years (OR 1.02, 95% CI 1.01 to 1.03) were predictive of less reverse remodeling on follow-up. In conclusion, preoperative LV end-systolic dimensions and LA dilatation substantially affect the likelihood of successful LA remodeling and normalization of all heart dimensions after mitral valve repair for MR. These findings support early operation for MR before the increase in heart dimensions is nonreversible.

Introduction Enhanced Recovery After Surgery (ERAS) pathways have been proven to increase patient satisfaction scores, decrease the complication rate, decrease the length of stay (LOS), and decrease cost for many surgical specialties. Recently, ERAS for cardiac surgery guidelines have been published and are being implemented in many centers. However, few data are reported on clinically important outcomes. We examined the effect of ERAS for cardiac patients on the duration of mechanical ventilation, ICU and hospital LOS.¹ Methods We retrospectively analyzed prospectively collected outcome data of patients undergoing cardiac surgery enrolled in the ERAS pathway (n = 115) compared to a historical standard care group (n = 188). The ERAS pathway included pre-operative patient education, multimodal pain management to minimize opioid usage, carbohydrate loading 2-4hrs before induction of anesthesia, minimizing crystalloid infusions, tight glucose control, early postoperative invasive access and chest tube removal, early extubation, and early mobilization. The standard care group was treated per preexisting institutional guidelines. Data were compared using univariate analysis: parametric and non-parametric data were analyzed with Student's t-test and Wilcoxon rank-sum test, respectively. A p-value of less than 0.05 was considered statistically significant. Results The median (25th, 75th) intensive care unit (ICU) length of stay (LOS) was 1 day (1, 2) in the ERAS group and 2 days (1, 3) in the standard care group (p Discussion The Enhanced Recovery Pathway after Surgery pathway uses a standardized approach to perioperative patient care. Implementation of ERAS for cardiac surgery results in shorter ICU and hospital LOS, comparable ICU and 30-day readmission rates, without a noticeable increase in 30-day mortality. Further studies focusing on other relevant outcome parameters are warranted.

Beginning in 2002, all 14 Massachusetts nonfederal cardiac surgery programs submitted Society of Thoracic Surgeons (STS) National Database data to the Massachusetts Data Analysis Center for mandatory state-based analysis and reporting, and to STS for nationally benchmarked analyses. We sought to determine whether longitudinal prevalences and trends in risk factors and observed and expected mortality differed between Massachusetts and the nation.We analyzed 2003 to 2014 expected (STS predicted risk of operative [in-hospital + 30-day] mortality), observed, and risk-standardized isolated coronary artery bypass graft mortality using Massachusetts STS data (N = 39,400 cases) and national STS data (N = 1,815,234 cases). Analyses included percentage shares of total Massachusetts coronary artery bypass graft volume and expected mortality rates of 2 hospitals before and after outlier designation.Massachusetts patients had significantly higher odds of diabetes, peripheral vascular disease, low ejection fraction, and age ≥75 years relative to national data and lower odds of shock (odds ratio, 0.66; 99% confidence interval, 0.53-0.83), emergency (odds ratio, 0.57, 99% confidence interval, 0.52-0.61), reoperation, chronic lung disease, dialysis, obesity, and female sex. STS predicted risk of operative [in-hospital + 30-day] mortality for Massachusetts patients was higher than national rates during 2003 to 2007 (P .001) and no different during 2008 to 2014 (P = .135). Adjusting for STS predicted risk of operative [in-hospital + 30-day] mortality, Massachusetts patients had significantly lower odds (odds ratio, 0.79; 99% confidence interval, 0.66-0.96) of 30-day mortality relative to national data. Outlier programs experienced inconsistent, transient influences on expected mortality and their percentage shares of Massachusetts coronary artery bypass graft cases.During 12 years of mandatory public reporting, Massachusetts risk-standardized coronary artery bypass graft mortality was consistently and significantly lower than national rates, expected rates were comparable or higher, and evidence for risk aversion was conflicting and inconclusive.

Objectives Functional status prior to coronary artery bypass graft surgery may be a risk factor for post-operative adverse events. We sought to examine the association between functional status in the 3 months prior to coronary artery bypass graft surgery and subsequent 180 day mortality. Design, setting, and participants We performed a single center retrospective cohort study in 718 adults who received coronary artery bypass graft surgery from 2002 to 2014. Exposures The exposure of interest was functional status determined within the 3 months preceding coronary artery bypass graft surgery. Functional status was measured and rated by a licensed physical therapist based on qualitative categories adapted from the Functional Independence Measure. Main outcomes and measures The main outcome was 180-day all-cause mortality. A categorical risk prediction score was derived based on a logistic regression model of the function grades for each assessment. Results In a logistic regression model adjusted for age, gender, New York Heart Association Class III/IV, chronic lung disease, hypertension, diabetes, cerebrovascular disease, and the Society of Thoracic Surgeons score, the lowest quartile of functional status was associated with an increased odds of 180-day mortality compared to patients with highest quartile of functional status [OR = 4.45 (95%CI 1.35, 14.69; P = 0.014)]. Conclusions Lower functional status prior to coronary artery bypass graft surgery is associated with increased 180-day all-cause mortality.

ObjectivePostoperative hyperglycemia is associated with poor clinical outcomes in patients undergoing cardiac surgery. However, some experts consider hyperglycemia to be an epiphenomenon related to acute stress. We investigated whether preoperative patient characteristics can predict hyperglycemia after cardiac surgery in nondiabetic patients.MethodsThis is a retrospective study of nondiabetic patients undergoing cardiac surgery at a single center during the years 2004 to 2009. Hyperglycemia was defined as 2 consecutive blood glucose readings of 150 mg/dL or greater during the 72 hours after cardiac surgery.ResultsThis study included 1453 patients with hyperglycemia and 2205 patients without hyperglycemia. Hyperglycemic patients were older, were more likely to be men, had higher body mass index, were more likely to be hypertensive and hypercholesterolemic, and had lower left ventricular ejection fractions; in addition, a greater proportion had a history of cardiovascular disease and renal failure. Multivariate logistic regression analysis showed age, gender, body mass index, preoperative serum creatinine, left ventricular ejection fraction, previous cardiac surgery, and preoperative cardiogenic shock to be independently associated with hyperglycemia (P

BACKGROUND: We hypothesized that metabolic profiles would differ in critically ill patients with malnutrition relative to those without. MATERIALS AND METHODS: We performed a prospective cohort study on 85 adult patients with systemic inflammatory response syndrome or sepsis admitted to a 20-bed medical intensive care unit (ICU) in Boston. We generated metabolomic profiles using gas and liquid chromatography and mass spectroscopy. We followed this by logistic regression and partial least squares discriminant analysis to identify individual metabolites that were significant. We then interrogated the entire metabolomics profile using metabolite set enrichment analysis and network model construction of chemical-protein target interactions to identify groups of metabolites and pathways that were differentiates in patients with and without malnutrition. RESULTS: Of the cohort, 38% were malnourished at admission to the ICU. Metabolomic profiles differed in critically ill patients with malnutrition relative to those without. Ten metabolites were significantly associated with malnutrition (P < .05). A parsimonious model of 5 metabolites effectively differentiated patients with malnutrition (AUC = 0.76), including pyroglutamine and hypoxanthine. Using pathway enrichment analysis, we identified a critical role of glutathione and purine metabolism in predicting nutrition. Nutrition status was associated with 28-day mortality, even after adjustment for known phenotypic variables associated with ICU mortality. Importantly, 7 metabolites associated with nutrition status were also associated with 28-day mortality. CONCLUSION: Malnutrition is associated with differential metabolic profiles early in critical illness. Common to all of our metabolome analyses, glutathione and purine metabolism, which play principal roles in cellular redox regulation and accelerated tissue adenosine triphosphate degradation, respectively, were significantly altered with malnutrition.

Emergency general surgery (EGS) patients are at an increased risk for morbidity and mortality compared with non-EGS patients. Limited information exists regarding the contribution of malnutrition to the outcome of critically ill patients who undergo EGS. We hypothesized that malnutrition would be associated with increased risk of 90-day all-cause mortality following intensive care unit (ICU) admission in EGS patients.We performed an observational study of patients treated in medical and surgical ICUs at a single institution in Boston. We included patients who underwent an EGS procedure and received critical care between 2005 and 2011. The exposure of interest, malnutrition, was determined by a registered dietitian's formal assessment within 48 hours of ICU admission. The primary outcome was all-cause 90-day mortality. Adjusted odds ratios were estimated by multivariable logistic regression models.The cohort consisted of 1361 patients. Sixty percent had nonspecific malnutrition, 8% had protein-energy malnutrition, and 32% were without malnutrition. The 30-day readmission rate was 18.9%. Mortality in-hospital and at 90 days was 10.1% and 17.9%, respectively. Patients with nonspecific malnutrition had a 1.5-fold increased odds of 90-day mortality (adjusted odds ratio [OR], 1.51; 95% confidence interval [CI], 1.09-5.04; P = .009) and patients with protein-energy malnutrition had a 3.1-fold increased odds of 90-day mortality (adjusted OR, 3.06; 95% CI, 1.89-4.92; P.001) compared with patients without malnutrition.In critically ill patients who undergo EGS, malnutrition at ICU admission is predictive of adverse outcomes. In survivors of hospitalization, malnutrition at ICU admission is associated with increases in readmission and mortality.

Ventricular assist device (VAD) support inpatients with a prosthetic heart valve had previously been considered a relative contraindication due to an increased risk of thromboembolic complications. We report our clinical experience of VAD implantation in patients with prosthetic heart valves, including both mechanical and bioprosthetic valves. The clinical records of 133 consecutive patients who underwent VAD implantation at a single institution from January 2002 through June 2009 were retrospectively reviewed. Six of these patients had a prosthetic valve in place at the time of device implantation. Patient demographics,operative characteristics, and postoperative complications were reviewed.Of the six patients,four were male.The mean age was 57.8 years (range 35–66 years). The various prosthetic cardiac valves included a mechanical aortic valve (n = 2), a bioprosthetic aortic valve (n = 3), and a mechanical mitral valve (n = 1).The indications for VAD support included bridge to transplantation (n = 2), bridge to recovery (n = 1), and postcardiotomy ventricular failure(n = 3). Three patients underwent left ventricular assist device placement and three received a right ventricular assist device. Postoperatively, standard anticoagulation management began with a heparin infusion (if possible)followed by oral anticoagulation.The 30-day mortality was50% (3/6). The mean duration of support among survivors was 194.3 days (range 7–369 days) compared with 16.0 days(range 4–29 days) for nonsurvivors. Of the three survivors,two were successfully bridged to heart transplantation and one recovered native ventricular function.Among the three nonsurvivors,acute renal failure developed in each case, and two developed heparin-induced thrombocytopenia. This study suggests that VAD placement in patients with a prosthethic heart valve, either mechanical or bioprosthetic,appears to be a reasonable option.

Objective 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have been shown to have pleiotropic effects in addition to their lipid-lowering properties. Some studies have shown the beneficial effect of preoperative statins on operative outcomes in coronary artery bypass grafting. However, the effect of preoperative statins in patients without coronary artery disease who undergo cardiac surgery remains poorly defined. Methods We performed a retrospective review of 1389 consecutive patients undergoing cardiac valve surgery between January of 2002 and December of 2005. Patients undergoing concomitant coronary artery bypass surgery and those with a history of myocardial infarction and coronary interventions were excluded. Of this cohort, 363 patients were receiving a statin preoperatively and 1026 patients were not. Propensity scores were constructed with patients' demographics, clinical data, and the year of procedure. Generalized estimating equations, including the propensity score as a covariate, were used to investigate whether preoperative statin use is associated with improved operative outcomes. Results The crude operative mortality rate was 0.8% and 2.3%, the incidence of stroke was 1.7% and 2.9%, and the incidence of perioperative myocardial infarction was 2.2% and 2.4% in the statin and non-statin groups, respectively. Generalized estimating equations showed that preoperative statin use is associated with lower mortality (odds ratio: 0.25, 95% confidential interval: 0.12–0.54). Preoperative statin use was not significantly associated with an incidence of stroke (odds ratio: 0.48, 95% confidential interval: 0.19–1.22) or perioperative myocardial infarction (odds ratio: 0.91, 95% confidential interval: 0.43–1.91) in this cohort. Conclusion Preoperative use of statins may improve operative outcomes in patients without coronary artery disease who undergo cardiac surgery.

With increasing prevalence of injected drug use in the United States, a growing number of intravenous drug users (IVDUs) are at risk for infective endocarditis (IE) that may require surgical intervention; however, few data exist about clinical outcomes of these individuals.We evaluated consecutive adult patients undergoing surgery for active IE between 2002 and 2014 pooled from 2 prospective institutional databases. Death and valve-related events, including reinfection or heart valve reoperation, thromboembolism, and anticoagulation-related hemorrhage were evaluated.Of the 436 patients identified, 78 (17.9%) were current IVDUs. The proportion of IVDUs increased from 14.8% in 2002 to 2004 to 26.1% in 2012 to 2014. IVDUs were younger (aged 35.9 ± 9.9 years vs 59.3 ± 14.1 years) and had fewer cardiovascular risk factors than non-IVDUs. During follow-up (median, 29.4 months; quartile 1-3, 4.7-72.6 months), adverse events among all patients included death in 92, reinfection in 42, valve-reoperation in 35, thromboembolism in 17, and hemorrhage in 16. Operative mortality was lower among IVDUs (odds ratio, 0.25; 95% confidence interval [CI], 0.06-0.71), but overall mortality was not significantly different (hazard ratio [HR], 0.78; 95% CI, 0.44-1.37). When baseline profiles were adjusted by propensity score, IVDUs had higher risk of valve-related complications (HR, 3.82; 95% CI, 1.95-7.49; P .001) principally attributable to higher rates of reinfection (HR, 6.20; 95% CI, 2.56-15.00; P .001).The proportion of IVDUs among surgically treated IE patients is increasing. Although IVDUs have lower operative risk, long-term outcomes are compromised by reinfection.

Background Surgical dogma suggests that homografts should be used preferentially, compared with conventional xenograft or mechanical prostheses, in the setting of infective endocarditis (IE), because they have greater resistance to infection. However, comparative data that support this notion are limited. Methods From the prospective databases of 2 tertiary academic centers, we identified 304 consecutive adult patients (age ≥17 years) who underwent surgery for active IE involving the aortic valve (AV), in the period 2002 to 2014. Short- and long-term outcomes were evaluated using propensity scores and inverse-probability weighting to adjust for selection bias. Results Homografts, and xenograft and mechanical prostheses, were used in 86 (28.3%), 139 (45.7%), and 79 (26.0%) patients, respectively. Homografts were more often used in the setting of prosthetic valve endocarditis (58.1% vs 28.8%, P = .002) and methicillin-resistant Staphylococcus (25.6% vs 12.1%, P = .002), compared with conventional prostheses. Early mortality occurred in 17 (19.8%) in the homograft group, and 20 (9.2%) in the conventional group ( P = .019). During follow-up (median: 29.4 months; interquartile-range: 4.7-72.6 months), 60 (19.7%) patients died, and 23 (7.7%) experienced reinfection, with no significant differences in survival ( P = .23) or freedom from reinfection rates ( P = .65) according to the types of prostheses implanted. After adjustments for baseline characteristics, using propensity-score analyses, use of a homograft did not significantly affect early death (odds ratio 1.61; 95% confidence interval [CI], 0.73-3.40, P = .23), overall death (hazard ratio 1.10; 95% CI, 0.62-1.94, P = .75), or reinfection (hazard ratio 1.04; 95% CI, 0.49-2.18, P = .93). Conclusions No significant benefit to use of homografts was demonstrable with regard to resistance to reinfection in the setting of IE. The choice among prosthetic options should be based on technical and patient-specific factors. Lack of availability of homografts should not impede appropriate surgical intervention.

Background. Choice of statistical methodology may significantly impact the results of provider profiling, including cardiac surgery report cards. Because of sample size and clustering issues, logistic regression may overestimate systematic interprovider variability, leading to false outlier classification. Theoretically, the use of hierarchical models should result in more accurate representation of provider performance. Methods. Extensively validated and audited data were available for all 4,603 isolated coronary artery bypass grafting procedures performed at 13 Massachusetts hospitals during 2002. To produce the official Massachusetts cardiac surgery report card, a 19-variable predictor set and a hierarchical generalized linear model were employed. For the current study, this same analysis was repeated with the 14 predictors used in the New York Cardiac Surgery Reporting System. Two additional analyses were conducted using each set of predictor variables and applying standard logistic regression. For each of the four combinations of predictors and models, the point estimates of risk-adjusted 30-day mortality, 95% confidence or probability intervals, and outlier status were determined for each hospital. Results. Overall unadjusted mortality for coronary bypass operations was 2.19%. For most hospitals, there was wide variability in the point estimates and confidence or probability intervals of risk-adjusted mortality depending on statistical model, but little variability relative to the choice of predictors. There were no hospital outliers using hierarchical models, but there was one outlier using logistic regression with either predictor set. Conclusions. When used to compare provider performance, logistic regression increases the possibility of false outlier classification. The use of hierarchical models is recommended.

We present a series of 405 consecutive patients agedor =80 years who underwent isolated or combined valve surgery over a 5-year period. Our results demonstrate that valve surgery in the elderly can be performed with acceptable early mortality, good late survival, and excellent late functional outcome.

We examined the impact of concomitant coronary artery bypass grafting (CABG) on hospital survival after aortic root replacement. We sought to determine whether CABG procedures that were not originally planned but rather added after the aortic root procedure was completed (CABG/bailout) skewed the results to shift patients with bad outcomes to the CABG group, making the non-CABG group appear undeservedly low risk.Between May 1992 and January 2001, 369 consecutive patients underwent aortic root replacement. Concomitant CABG was required in 95 patients (26%). Indications for CABG were significant coronary artery disease in 73 patients (20%), active endocarditis or acute aortic dissection involving the coronary orifices in 14 patients (4%), and difficulty weaning from bypass because of regional wall motion abnormality from presumed but unconfirmed coronary artery disease or technical error at coronary ostial reimplantation (CABG/bailout) in 8 patients (2%).Operative mortality for the entire cohort was 5.7% (21 patients). The operative mortality rate for the non-CABG group was 0.4% (1 of 274 patients), and for the CABG group, 21% (20 of 95 patients; p0.001). Independent predictors of operative mortality in the CABG group were New York Heart Association functional class III or IV (odds ratio, 3.9; 95% confidence interval, 1.07 to 14.5), active endocarditis (odds ratio, 9.2; 95% confidence interval, 2.06 to 41.5), acute aortic dissection (odds ratio, 7.6; 95% confidence interval, 1.81 to 32.0), and failure to use retrograde cardioplegia (odds ratio, 6.4; 95% confidence interval, 1.06 to 38.8). The use of CABG/bailout was not a predictor.Adding CABG at the end of an aortic root procedure is a rare event, and because it is rare, there is no significant shift of risk as a result of the CABG/bailout patients on the overall CABG group.

Objectives The goal of this study was to determine if a “hybrid” approach to the treatment of complex combined coronary and valve disease is superior to the results predicted by a Society of Thoracic Surgeons9 (STS) algorithm with conventional coronary artery bypass graft (CABG)/valve surgery in high-risk patients. Background With advancements in percutaneous coronary interventions (PCIs), some patients requiring coronary revascularization and valve surgery may benefit from a hybrid approach involving initial planned PCI followed by valve surgery, rather than conventional CABG/valve surgery. Methods We retrospectively analyzed 26 consecutive patients with coronary artery and valve disease who underwent planned initial PCI followed by valve surgery during the same hospital stay between September 1997 and August 2003. We calculated the predicted mortality at the time of PCIand compared it with the observed mortality. Results There were 12 male and 14 female patients with a median age of 72 years (range 53 to 91 years). Balloon angioplasty was performed in all patients, followed by stenting in 22 (85%) patients. Within a median of 5 days (range 0 to 14 days), 15 patients (58%) underwent primary and 11 patients (42%) underwent re-operative valve surgery. Operative mortality was 1 of 26 patients (3.8%), dramatically lower than the STS-predicted mortality of 22%. Median blood loss was 900 ml, and 22 patients (85%) required blood transfusions. Survival at 1, 3, and 5 years was 78%, 56%, and 44%, respectively. Conclusions Hybrid initial PCI followed by staged valve surgery represents an excellent alternative to conventional CABG/valve surgery in some high-risk patients, particularly those who present in shock after myocardial infarction. Lower mortality rates come at the cost of more bleeding and transfusion requirements.

Background With advances in percutaneous coronary interventions, many patients now referred for coronary artery bypass grafting have diffuse coronary artery disease. We undertook this retrospective study to determine whether left anterior descending (LAD) coronary endarterectomy is a safe and effective long-term adjunct to coronary artery bypass grafting in patients who cannot otherwise be completely revascularized. Methods Between January 1992 and March 2000, 196 of 7,633 (2.5%) consecutive patients underwent LAD coronary endarterectomy with coronary artery bypass grafting. Median age was 67 years (range, 33 to 97 years), 101 patients (52%) had unstable angina, and 182 (93%) were in New York Heart Association class III or IV. Thirty-three patients (17%) had ongoing myocardial infarction; another 17 (9%) had myocardial infarction less than 1 month. Thirty patients (15%) required intraaortic balloon pump preoperatively and 19 (10%) were reoperations. Results All patients underwent LAD endarterectomy with coronary artery bypass grafting to the LAD. The left internal mammary artery was grafted to the LAD in 151 patients (77%), and 46 of 151 (30%) of these required an additional vein patch to the endarterectomized bed. Concomitant valve procedures were performed in 8 (4%) patients. Overall hospital mortality was 3% (6 of 196). Perioperative myocardial infarction in the LAD territory was 3%. One-year survival was 94% (95% confidence interval, 90% to 97%), whereas 5-year survival was 74% (95% confidence interval, 66% to 80%). Freedom from cardiac events (angina, myocardial infarction, congestive heart failure, percutaneous coronary interventions) was 90% (95% confidence interval, 84% to 94%) at 1 year and 84% (95% confidence interval, 75% to 90%) at 5 years. Conclusions Despite the presence of diffuse coronary artery disease, coronary artery bypass grafting with LAD endarterectomy offers excellent results with very low hospital mortality and morbidity, and favorable long-term survival.

BACKGROUND "Prophylactic" aortic valve replacement (AVR) in patients with asymptomatic, mild-to-moderate aortic stenosis (AS) at the time of CABG is controversial. In 1994, we reported our initial experience involving 44 patients and have now updated our series in an attempt to further evaluate outcomes. METHODS Between January 1992 and July 2001, 100 consecutive patients underwent reoperative AVR following previous CABG. Forty patients had their initial surgery at the Brigham & Women's Hospital (BWH) and 60 patients had their coronary surgery elsewhere. None of the 40 BWH patients had a mean valve gradient greater than 25 mmHg at the time of CABG. RESULTS The mean time interval from CABG to AVR for the entire group was 9.0 years (range: 1.4-21 years). Overall operative mortality (OM) was 7% including 5 deaths (10.2%) among 49 patients requiring additional CABG at the time of AVR and 2 deaths (3.9%) among 51 patients without additional coronary artery intervention. This OM rate was a notable decrease from our earlier report of 18.2% (P = 0.07). Furthermore, operative mortality decreased progressively from 15.4% in 1992-1993 to 0% in 2000-2001 (P = NS). CONCLUSION The OM of reoperative AVR following CABG has fallen in recent years. Given the relevance of newer techniques and approaches, it may be reasonable to adopt an expectant management approach in patients with asymptomatic mild-to-moderate AS (i.e., mean systolic gradient less than 25 mmHg) at the time of CABG.

We hypothesized that preexisting malnutrition in patients who survived critical care would be associated with adverse outcomes following hospital discharge.We performed an observational cohort study in 1 academic medical center in Boston. We studied 23,575 patients, aged ≥18 years, who received critical care between 2004 and 2011 and survived hospitalization.The exposure of interest was malnutrition determined at intensive care unit (ICU) admission by a registered dietitian using clinical judgment and on data related to unintentional weight loss, inadequate nutrient intake, and wasting of muscle mass and/or subcutaneous fat. The primary outcome was 90-day postdischarge mortality. Secondary outcome was unplanned 30-day hospital readmission. Adjusted odds ratios were estimated by logistic regression models adjusted for age, race, sex, Deyo-Charlson Index, surgical ICU, sepsis, and acute organ failure. In the cohort, the absolute risk of 90-day postdischarge mortality was 5.9%, 11.7%, 15.8%, and 21.9% in patients without malnutrition, those at risk of malnutrition, nonspecific malnutrition, and protein-energy malnutrition, respectively. The odds of 90-day postdischarge mortality in patients at risk of malnutrition, nonspecific malnutrition, and protein-energy malnutrition fully adjusted were 1.77 (95% confidence interval [CI], 1.23-2.54), 2.51 (95% CI, 1.36-4.62), and 3.72 (95% CI, 2.16-6.39), respectively, relative to patients without malnutrition. Furthermore, the presence of malnutrition is a significant predictor of the odds of unplanned 30-day hospital readmission.In patients treated with critical care who survive hospitalization, preexisting malnutrition is a robust predictor of subsequent mortality and unplanned hospital readmission.

The association between obesity and mortality in critically ill patients is unclear based on the current literature. To clarify this relationship, we analyzed the association between obesity and mortality in a large population of critically ill patients and hypothesized that mortality would be impacted by nutritional status.We performed a single-center observational study of 6,518 adult patients treated in medical and surgical ICUs between 2004 and 2011. All patients received a formal, in-person, and standardized evaluation by a registered dietitian. Body mass index was determined at the time of dietitian consultation from the estimated dry weight or hospital admission weight and categorized a priori as less than 18.5 kg/m (underweight), 18.5-24.9 kg/m (normal/referent), 25-29.9 kg/m (overweight), 30-39.9 kg/m (obesity class I and II), and more than or equal to 40.0 kg/m (obesity class III). Malnutrition diagnoses were categorized as nonspecific malnutrition, protein-energy malnutrition, or well nourished. The primary outcome was all-cause 30-day mortality determined by the Social Security Death Master File. Associations between body mass index groups and mortality were estimated by bivariable and multivariable logistic regression models. Adjusted odds ratios were estimated with inclusion of covariate terms thought to plausibly interact with both body mass index and mortality. We utilized propensity score matching on baseline characteristics and nutrition status to reduce residual confounding of the body mass index category assignment.In the cohort, 5% were underweight, 36% were normal weight, 31% were overweight, 23% had class I/II obesity, and 5% had class III obesity. Nonspecific malnutrition was present in 56%, protein-energy malnutrition was present in 12%, and 32% were well nourished. The 30-day and 90-day mortality rate for the cohort was 19.1 and 26.6%, respectively. Obesity is a significant predictor of improved 30-day mortality following adjustment for age, gender, race, medical versus surgical patient type, Deyo-Charlson index, acute organ failure, vasopressor use, and sepsis: underweight odds ratio 30-day mortality is 1.09 (95% CI, 0.80-1.48), overweight 30-day mortality odds ratio is 0.93 (95% CI, 0.80-1.09), class I/II obesity 30-day mortality odds ratio is 0.80 (95% CI, 0.67-0.96), and class III obesity 30-day mortality odds ratio is 0.69 (95% CI, 0.49-0.97), all relative to patients with body mass index 18.5-24.9 kg/m. Importantly, there is confounding of the obesity-mortality association on the basis of malnutrition. Adjustment for only nutrition status attenuates the obesity-30-day mortality association: underweight odds ratio is 0.74 (95% CI, 0.54-1.00), overweight odds ratio is 1.05 (95% CI, 0.90-1.23), class I/II obesity odds ratio is 0.96 (95% CI, 0.81-1.15), and class III obesity odds ratio is 0.81 (95% CI, 0.59-1.12), all relative to patients with body mass index 18.5-24.9 kg/m. In a subset of patients with body mass index more than or equal to 30.0 kg/m (n = 1,799), those with either nonspecific or protein-energy malnutrition have increased mortality relative to well-nourished patients with body mass index more than or equal to 30.0 kg/m: odds ratio of 90-day mortality is 1.67 (95% CI, 1.29-2.15; p0.0001), fully adjusted. In a cohort of propensity score matched patients (n = 3,554), the body mass index-mortality association was not statistically significant, likely from matching on nutrition status.In a large population of critically ill adults, the association between improved mortality and obesity is confounded by malnutrition status. Critically ill obese patients with malnutrition have worse outcomes than obese patients without malnutrition.

The systemic immune response is a dynamic process involving the trafficking of lymphocytes from the Ag-stimulated lymph node to the peripheral tissue. Studies in sheep have demonstrated several phases of cell output in the efferent lymph after Ag stimulation. When skin contact sensitizers are used as Ag, the efferent lymph cell output peaks ∼96 h after Ag stimulation and is temporally associated with the recruitment of cells into the skin. To investigate the relative contribution of this high-output phase of efferent lymphocytes to lymphocytic inflammation in the skin, we used a common contact sensitizer 2-phenyl-4-ethoxymethylene-5-oxazolone (oxazolone) to stimulate the skin and draining prescapular lymph node of adult sheep. The efferent lymph ducts draining the Ag-stimulated and contralateral control lymph nodes were cannulated throughout the experimental period. The lymphocytes leaving the lymph nodes during the 72-h period before maximum infiltration were differentially labeled with fluorescent tracers, reinjected into the arterial circulation, and tracked to the site of Ag stimulation. Quantitative tissue cytometry of the skin at the conclusion of the injection period (96 h after Ag stimulation) demonstrated more migratory cells derived from the Ag-stimulated lymph node than the contralateral control (median 18.5 vs 15.5 per field; p < 0.05). However, when corrected for total cell output of the lymph node, the Ag-stimulated migratory cells were 3.8-fold more prevalent in the skin than the contralateral control cells. These results suggest that the in situ immune response generally mirrors the frequency of recruitable lymphocytes in the peripheral blood.

The pathogenesis of acute lymphocytic inflammation in the lower respiratory tract appears to involve the recruitment of lymphocytes out of the blood stream and into the extravascular lung tissue. To investigate the membrane molecules regulating this process, we used the intrabronchial instillation of cellular antigen to trigger lymphocyte recruitment into the lower respiratory tract. Sheep presensitized 6 to 10 weeks earlier at a remote site were intrabronchially challenged with 1-5 x 10(7) cells from a B lymphoblastoid cell line. The cells were instilled into a subsegmental bronchus through a bronchial catheter. The stimulated and contralateral control segments were studied at a peak of inflammation, approximately 72 hours after antigen stimulation. Gross and microscopic studies of the stimulated segment demonstrated localized inflammation characterized by the perivascular infiltration of lymphocytes. In contrast, control areas of the lung demonstrated only scattered perivascular lymphocytes. Immunohistochemistry of the stimulated lung showed that the majority of these perivascular cells were CD3+ CD4+ lymphocytes. The T lymphocytes expressed high levels of the cell adhesion molecules beta 1 integrin and LFA-1, but low levels of the L-selectin membrane molecule. Immunohistochemistry of the endothelial cells associated with the lymphocyte infiltrates demonstrated intense staining of the ICAM-1, and beta 1 integrin adhesion molecules. Electron microscopic studies of the endothelial cells in the antigen stimulated areas of the lung confirmed morphologic changes consistent with endothelialitis. These results suggest that the intrabronchial instillation of cellular antigen stimulates an angiocentric T-cell infiltration regulated by activated pulmonary endothelial cells. The histologic and morphologic findings are remarkably similar to those observed during acute lung transplant rejection.

Purpose: This study was aimed at comparing the effects of a neutral liquid and a neutral gas used as intraamniotic media on umbilical blood flow, O 2 delivery, blood pressure, acid-base status, and electrolytes in the fetus at escalating intraamniotic pressures. Methods: Eight fetal lambs underwent invasive monitoring of common umbilical blood flow, blood pressure, blood gases, sodium, and hematocrit, as intraamniotic pressure was raised from 0 to 30 mm Hg. The animals were divided equally in two groups depending on the intraamniotic medium used (group I, warmed saline and group, II, air). Maternal systemic blood pressure, O 2 saturation, and temperature were kept constant. Results: In each group, a threshold level of intraamniotic pressure was evident, above which there was a significant decrease in the common umbilical artery blood flow, with concomitant fetal hypoxemia and hypercarbia. This intraamniotic pressure threshold was 20 mm Hg in group I (saline), but only 15 mm Hg in group II (air). Conclusions: Although both a neutral liquid and a neutral gas can safely be used as intraamniotic media, a neutral liquid medium allows for a wider range of safe intrauterine working pressure (0 to 20 mm Hg), as compared with a neutral gas (0–15 mm Hg).

To compare the short-term and long-term outcomes of mitral valve repair (MVP) versus mitral valve replacement (MVR) in elderly patients.All patients, age 70 years or greater, with mitral regurgitation who underwent MVP or MVR with or without coronary artery bypass graft (CABG), tricuspid valve surgery, or a maze procedure between 2002 and 2011 were retrospectively identified. Patients with a rheumatic cause or who underwent concomitant aortic valve or ventricular-assist device procedures were excluded.Overall, 556 patients underwent MVP and 102 patients underwent MVR. The mean age of the patients in the MVR group was 78 years versus 77 years for those in the MVP group (P.02). The patients in the MVR group had a better mean left ventricular ejection fraction than those in the MVP group (60% vs 55%, P=.04). The incidence of concomitant CABG, tricuspid valve operations, and atrial fibrillation ablation procedures was similar in both groups, but perfusion time was significantly longer for the MVR group (median 177 minutes vs 146 minutes for MVP, P=.001). Postoperatively, patients in the MVR group had a higher incidence of stroke (6% vs 2%, P.10) and significantly longer intensive care unit stay (median 86 hours vs 55 hours, P=.001) and hospital stay (9 days vs 8 days, P.01). Operative mortality of patients was significantly higher for the MVR group (8.8% vs 3.6%, P=.03) and remained significant long-term on Kaplan-Meier analysis. Cox regression analysis of all 658 patients and propensity-matched analysis of 96 patients also confirmed these results.Elderly patients with mitral regurgitation who undergo MVP have better postoperative outcomes, lower operative mortality, and improved long-term survival than those undergoing MVR. MVP is a safe and more effective option for the elderly with mitral regurgitation.

This case report illustrates the presentation, diagnosis, and surgical management of an anomalous origin of the right coronary artery from the left coronary sinus in a young adult in whom the right coronary artery was reimplanted directly onto the aorta, rather than bypassed, as is typically done.

Bivalirudin is direct thrombin inhibitor used in patients with heparin-induced thrombocytopenia. A pharmacokinetic and — dynamic model that predicts the partial thromboplastin time (PTT) based on the past infusion rates of bivalirudin following dose adjustment would be useful to guide optimal therapy. In this retrospective study we randomized 132 patients to a derivation and a validation cohort, and tested two models. The first model is a single-state linear model; the other incorporates a non-linear element to account for renal elimination of bivalirudin. Both models predicted PTT changes equally well with root-mean squared errors of 15 to 16 seconds (Pearson correlation coefficients for both were 0.67). Intra- and inter-individual variability of response to bivalirudin was significant. Although a high percentage of patients had moderate to severe renal dysfunction at one point during the bivalirudin infusion, the non-linear model that incorporates variable renal clearance of drug did not perform better than the linear model. This finding persisted even in the subgroup analysis of patients with moderate and low estimated glomerular filtration rates.

We hypothesized that increased postgraduate surgical experience correlates with improved operative efficiency and long-term survival in standard cardiac surgery procedures.Utilizing a prospectively collected retrospective database, we identified patients who underwent isolated coronary artery bypass grafting (CABG) (n = 3726), aortic valve replacement (AVR) (n = 1626), mitral valve repair (n = 731), mitral valve replacement (MVR) (n = 324), and MVR + AVR (n = 184) from January 2002 through June 2012. After adjusting for patient risk and surgeon variability, we evaluated the influence of surgeon experience on cardiopulmonary bypass and crossclamp times, and long-term survival.Mean surgeon experience after fellowship graduation was 16.0 ± 11.7 years (range, 1.0-35.2 years). After adjusting for patient risk and surgeon-level fixed effects, learning curve analyses demonstrated improvements in cardiopulmonary bypass and crossclamp times with increased surgeon experience. There was marginal improvement in the predictability (R(2) value) of cardiopulmonary bypass and crossclamp time for CABG with the addition of surgeon experience; however, all other procedures had marked increases in the R(2) following addition of surgeon experience. Cox proportional hazard models revealed that increased surgeon experience was associated with improved long-term survival in AVR (hazard ratio [HR], 0.85; P .0001), mitral valve repair (HR, 0.73; P .0001), and MVR + AVR (HR, 0.95; P = .006) but not in CABG (HR, 0.80; P = .15), and a trend toward significance in MVR (HR, 0.87; P = .09).In cardiac surgery, not including CABG, surgeon experience is an important determinant of operative efficiency and of long-term survival.

To test the hypothesis that subcutaneous administration of basal insulin begun immediately after cardiac surgery can decrease the need for insulin infusion in patients without diabetes and save nursing time.After cardiac surgery, 36 adult patients without diabetes were randomly assigned to receive either standard treatment (control group) or insulin glargine once daily in addition to standard treatment (basal insulin group). Standard treatment included blood glucose measurements every 1 to 4 hours and intermittent insulin infusion to maintain blood glucose levels between 100 and 150 mg/dL. The study period lasted up to 72 hours.There were no differences in demographics or baseline laboratory characteristics of the 2 study groups. Mean daily blood glucose levels were lower in the basal insulin group in comparison with the control group, but the difference was not statistically significant (129.3 ± 9.4 mg/dL versus 132.6 ± 7.3 mg/dL; P = .25). The mean duration of insulin infusion was significantly shorter in the basal insulin group than in the control group (16.3 ± 10.7 hours versus 26.6 ± 17.3 hours; P = .04). Nurses tested blood glucose a mean of 8.3 ± 3.5 times per patient per day in the basal insulin group and 12.0 ± 4.7 times per patient per day in the control group (P = .01). There was no occurrence of hypoglycemia (blood glucose level60 mg/dL) in either group.Once-daily insulin glargine is safe and may decrease the duration of insulin infusion and reduce nursing time in patients without diabetes who have hyperglycemia after cardiac surgery.

Ventricular assist device (VAD) support inpatients with a prosthetic heart valve had previously been considered a relative contraindication due to an increased risk of thromboembolic complications. We report our clinical experience of VAD implantation in patients with prosthetic heart valves, including both mechanical and bioprosthetic valves. The clinical records of 133 consecutive patients who underwent VAD implantation at a single institution from January 2002 through June 2009 were retrospectively reviewed. Six of these patients had a prosthetic valve in place at the time of device implantation. Patient demographics,operative characteristics, and postoperative complications were reviewed.Of the six patients,four were male.The mean age was 57.8 years (range 35–66 years). The various prosthetic cardiac valves included a mechanical aortic valve (n = 2), a bioprosthetic aortic valve (n = 3), and a mechanical mitral valve (n = 1).The indications for VAD support included bridge to transplantation (n = 2), bridge to recovery (n = 1), and postcardiotomy ventricular failure(n = 3). Three patients underwent left ventricular assist device placement and three received a right ventricular assist device. Postoperatively, standard anticoagulation management began with a heparin infusion (if possible)followed by oral anticoagulation.The 30-day mortality was50% (3/6). The mean duration of support among survivors was 194.3 days (range 7–369 days) compared with 16.0 days(range 4–29 days) for nonsurvivors. Of the three survivors,two were successfully bridged to heart transplantation and one recovered native ventricular function.Among the three nonsurvivors,acute renal failure developed in each case, and two developed heparin-induced thrombocytopenia. This study suggests that VAD placement in patients with a prosthethic heart valve, either mechanical or bioprosthetic,appears to be a reasonable option.

Background. Improved understanding of the incidence and risk factors for operative complications and longterm mortality following coronary artery bypass grafting (CABG) is needed to better define the optimal role for CABG in patients with chronic kidney disease (CKD). Methods. We analysed 2438 patients who underwent CABG at a single centre between 2005 and 2008. Multivariable regression was used to analyse associations and to generate a CKD-specific predictive tool. Results. Operative mortality was 4.8% in individuals with stage 3 CKD, 7.1% in individuals with stage 4–5 CKD and 2.2% in those without significant CKD (P< 0.001). CKD was associated with post-operative blood transfusion, acute kidney injury, myocardial injury and cardiac arrest, and use of exogenous blood and acute kidney injury were strongly associated with in-hospital death in CKD patients. Patients with stage 3 (HR 1.64, 95% CI 1.30–45.94) and stage 4–5 CKD (HR 2.77, 95% CI 1.00–2.68) were more likely to die during follow-up than those without CKD, but mortality rates were low among patients who survived to discharge—stage 3 (0.006 deaths/year) and stage 4–5 CKD (0.009/year). A scoring system including urgent or emergent surgery (OR 2.30), prior cardiac surgery (OR 3.06), concurrent valve surgery (OR 2.06), preoperative shock (OR 6.18), and prior stroke (OR 1.98) had 96.4% percent specificity for the detection of in-hospital death in patients with CKD. Conclusions. Perioperative mortality and morbidity remain more frequent in patients with stage 3–5 CKD than patients with preserved renal function, but long-term outcomes in patients surviving hospitalization are favourable. We have developed a predictive tool that holds promise as a means of identifying CKD patients most likely to survive surgery and benefit from CABG.

Monoclonal antibodies are an important resource for defining molecular expression and probing molecular function. The characterization of monoclonal antibody reactivity patterns, however, can be costly and inefficient in nonhuman experimental systems. To develop a computational approach to the pattern analysis of monoclonal antibody reactivity, we analyzed a panel of 128 monoclonal antibodies recognizing sheep antigens. Quantitative single parameter flow cytometry histograms were obtained from five cell types isolated from normal animals. The resulting 640 histograms were smoothed using a Gaussian kernel over a range of bandwidths. Histogram features were selected by SiZer—an analytic tool that identifies statistically significant features. The extracted histogram features were compared and grouped using hierarchical clustering. The validity of the clustering was indicated by the accurate pairing of externally verified molecular reactivity. We conclude that our computational algorithm is a potentially useful tool for both monoclonal antibody classification and molecular taxonomy in nonhuman experimental systems.

This paper discusses several types of interoperability for medical applications and devices: the ability of applications to run on any platform; how modularity affects interoperability; and data exchange between heterogeneous applications. It draws from experience with Internet standardization to find lessons for creating standards for interoperability.

We describe the patterns of utilization of arterial blood gas (ABG) tests in a large tertiary care hospital. To our knowledge, no hospital-wide analysis of ABG test utilization has been published. We analyzed 491 ABG tests performed during 24 two-hour intervals, representative of different staff shifts throughout the 7-day week. The clinician ordering each ABG test was asked to fill out a utilization survey. The most common reasons for requesting an ABG test were changes in ventilator settings (27.6%), respiratory events (26.4%), and routine (25.7%). Of the results, approximately 79% were expected, and a change in patient management (eg, a change in ventilator settings) occurred in 42% of cases. Many ABG tests were ordered as part of a clinical routine or to monitor parameters that can be assessed clinically or through less invasive testing. Implementation of practice guidelines may prove useful in controlling test utilization and in decreasing costs.

The renoprotective effect of preoperative statin use in coronary artery bypass grafting remains poorly defined. A retrospective review of 1,802 consecutive patients who underwent isolated coronary artery bypass grafting from January 2002 to October 2005 was performed. Of those, 1,039 patients were receiving statins preoperatively, and 763 patients were not. Two propensity score-matched cohorts each of 641 patients (statin and nonstatin groups) were constructed. Multivariate logistic regression analyses for matched patients and all patients were performed to investigate whether preoperative statin use was associated with the incidence of new renal insufficiency. In a matched analysis, the statin group had a lower incidence of new renal insufficiency than the nonstatin group (1.6% vs 3.9%, odds ratio 0.39, 95% confidential interval 0.18 to 0.82, p = 0.01). Multivariate logistic regression analysis including all patients also showed that preoperative statin use (odds ratio 0.54, 95% confidence interval 0.30 to 0.99, p = 0.047) was significantly associated with low incidence of new postoperative renal insufficiency. In conclusion, preoperative statin use may be renoprotective after coronary artery bypass grafting.