Factors Shaping the Implementation of Strategies to Prevent Acute Kidney Injury: A Qualitative Study.

Reducing the prevalence of acute kidney injury (AKI) is an important patient safety objective set forth by the National Quality Forum. Despite international guidelines to prevent AKI, there continues to be an inconsistent uptake of these interventions by cardiac teams across practice settings. The IMPROVE-AKI study was designed to test the effectiveness and implementation of AKI preventive strategies delivered through team-based coaching activities. Qualitative methods were used to identify factors that shaped sites' implementation of AKI prevention strategies. Semi-structured interviews were conducted with staff in a range of roles within the cardiac catheterization laboratories, including nurses, laboratory managers, and interventional cardiologists (N = 50) at multiple time points over the course of the study. Interview transcripts were qualitatively coded, and aggregated code reports were reviewed to construct main themes through memoing. In this paper, we report insights from semi-structured interviews regarding workflow, organizational culture, and leadership factors that impacted implementation of AKI prevention strategies.

Sex differences in outcomes among adults undergoing abdominal aortic aneurysm repair.

OBJECTIVE: Although the differences in short-term outcomes between male and female patients in abdominal aortic aneurysm (AAA) repair have been well studied, it remains unclear if these sex disparities extend to other long-term adverse outcomes after AAA repair, such as reintervention and late rupture. METHODS: We performed a retrospective cohort study of 13,007 patients who underwent either endovascular (EVAR) or open AAA repair (OAR) between 2003 and 2015 using data from the Vascular Quality Initiative registries. Eligible patients were linked to fee-for-service Medicare claims to identify late outcomes of rupture and aneurysm-specific reintervention. RESULTS: The mean age of our cohort was 76 ± 6.7 years, 22% were female, 94% were White, and 77% underwent EVAR. The 10-year rupture incidence was slightly higher for women at 4.8 per 1000 person-years, vs 3.9 for men, but this difference was not statistically significant after risk adjustment (hazard ratio [HR] = 1.13, 95% confidence interval [CI]: 0.74-1.73). Likewise, we found no sex difference in reintervention rates (5.1 vs 4.8 in women per 1000 person-years) even after risk adjustment (HR = 0.95, 95% CI: 0.83-1.09). Regression models suggest effect modification by repair type for reintervention, where women who underwent index EVAR had a higher risk of reintervention than men (HR = 1.08, 95% CI: 0.93-1.26), whereas women who underwent OAR were at a lower risk of reintervention than men (HR = 0.79, 95% CI: 0.58-1.08); however, neither effect reached statistical significance within each subgroup. In addition, we found that the risk of reintervention for women vs men varied by clinical presentation, where women were less likely to undergo reintervention after an elective or symptomatic AAA repair but were more likely to undergo reintervention after a repair for AAA rupture (HR = 1.70, 95% CI: 1.05-2.75). CONCLUSIONS: Male and female patients who underwent AAA repair had similar rates of reintervention and late aneurysm rupture in the 10 years after their procedure. However, our findings suggest that repair type and clinical presentation may affect the role of sex in clinical outcomes and warrant further exploration in these subgroups.

Association between sex and long-term outcomes of endovascular treatment for peripheral artery disease.

BACKGROUND: Endovascular peripheral vascular intervention (PVI) has become the primary revascularization technique used for peripheral artery disease (PAD). Yet, there is limited understanding of long-term outcomes of PVI among women versus men. In this study, our objective was to investigate sex differences in the long-term outcomes of patients undergoing PVI. METHODS: We performed a cohort study of patients undergoing PVI for PAD from January 1, 2010 to September 30, 2015 using data in the Vascular Quality Initiative (VQI) registry. Patients were linked to fee-for-service Medicare claims to identify late outcomes including major amputation, reintervention, major adverse limb event (major amputation or reintervention [MALE]), and mortality. Sex differences in outcomes were evaluated using cumulative incidence curves, Gray's test, and mixed effects Cox proportional hazards regression accounting for patient and lesion characteristics using inverse probability weighted estimates. RESULTS: In this cohort of 15,437 patients, 44% (n = 6731) were women. Women were less likely to present with claudication than men (45% vs. 49%, p < 0.001, absolute standardized difference, d = 0.08) or be able to ambulate independently (ambulatory: 70% vs. 76%, p < 0.001, d = 0.14). There were no major sex differences in lesion characteristics, except for an increased frequency of tibial artery treatment in men (23% vs. 18% in women, p < 0.001, d = 0.12). Among patients with claudication, women had a higher risk-adjusted rate of major amputation (hazard ratio [HR] = 1.72, 95% confidence interval [CI]: 1.18-2.49), but a lower risk of mortality (HR = 0.86, 95% CI: 0.75-0.99). There were no sex differences in reintervention or MALE for patients with claudication. However, among patients with chronic limb-threatening ischemia, women had a lower risk-adjusted hazard of major amputation (HR = 0.79, 95% CI: 0.67-0.93), MALE (HR = 0.86, 95% CI: 0.78-0.96), and mortality (HR = 0.86, 95% CI: 0.79-0.94). CONCLUSION: There is significant heterogeneity in PVI outcomes among men and women, especially after stratifying by symptom severity. A lower overall mortality in women with claudication was accompanied by a higher risk of major amputation. Men with chronic limb-threatening ischemia had a higher risk of major amputation, MALE, and mortality. Developing sex-specific approaches to PVI that prioritizes limb outcomes in women can improve the quality of vascular care for men and women.

Quantifying differences in packaged food and drink purchases among households with diet-related cardiometabolic multi-morbidity: a cross-sectional analysis.

BACKGROUND: Diet is important for chronic disease management, with limited research understanding dietary choices among those with multi-morbidity, the state of having 2 or more chronic conditions. The objective of this study was to identify associations between packaged food and drink purchases and diet-related cardiometabolic multi-morbidity (DRCMM). METHODS: Cross-sectional associations between packaged food and drink purchases and household DRCMM were investigated using a national sample of U.S. households participating in a research marketing study. DRCMM households were defined as household head(s) self-reporting 2 or more diet-related chronic conditions. Separate multivariable logistic regression models were used to model the associations between household DRCMM status and total servings of, and total calories and nutrients from, packaged food and drinks purchased per month, as well as the nutrient density (protein, carbohydrates, and fat per serving) of packaged food and drinks purchased per month, adjusted for household size. RESULTS: Among eligible households, 3795 (16.8%) had DRCMM. On average, households with DRCMM versus without purchased 14.8 more servings per capita, per month, from packaged foods and drinks (p < 0.001). DRCMM households were 1.01 times more likely to purchase fat and carbohydrates in lieu of protein across all packaged food and drinks (p = 0.002, p = 0.000, respectively). DRCMM households averaged fewer grams per serving of protein, carbohydrates, and fat per month across all food and drink purchases (all p < 0.001). When carbonated soft drinks and juices were excluded, the same associations for grams of protein and carbohydrates per serving per month were seen (both p < 0.001) but the association for grams of fat per serving per month attenuated. CONCLUSIONS: DRCMM households purchased greater quantities of packaged food and drinks per capita than non-DRCMM households, which contributed to more fat, carbohydrates, and sodium in the home. However, food and drinks in DRCMM homes on average were lower in nutrient-density. Future studies are needed to understand the motivations for packaged food and drink choices among households with DRCMM to inform interventions targeting the home food environment.

Can diverse population characteristics be leveraged in a machine learning pipeline to predict resource intensive healthcare utilization among hospital service areas?

BACKGROUND: Super-utilizers represent approximately 5% of the population in the United States (U.S.) and yet they are responsible for over 50% of healthcare expenditures. Using characteristics of hospital service areas (HSAs) to predict utilization of resource intensive healthcare (RIHC) may offer a novel and actionable tool for identifying super-utilizer segments in the population. Consumer expenditures may offer additional value in predicting RIHC beyond typical population characteristics alone. METHODS: Cross-sectional data from 2017 was extracted from 5 unique sources. The outcome was RIHC and included emergency room (ER) visits, inpatient days, and hospital expenditures, all expressed as log per capita. Candidate predictors from 4 broad groups were used, including demographics, adults and child health characteristics, community characteristics, and consumer expenditures. Candidate predictors were expressed as per capita or per capita percent and were aggregated from zip-codes to HSAs using weighed means. Machine learning approaches (Random Forrest, LASSO) selected important features from nearly 1,000 available candidate predictors and used them to generate 4 distinct models, including non-regularized and LASSO regression, random forest, and gradient boosting. Candidate predictors from the best performing models, for each outcome, were used as independent variables in multiple linear regression models. Relative contribution of variables from each candidate predictor group to regression model fit were calculated. RESULTS: The median ER visits per capita was 0.482 [IQR:0.351-0.646], the median inpatient days per capita was 0.395 [IQR:0.214-0.806], and the median hospital expenditures per capita was $2,302 [1$,544.70-$3,469.80]. Using 1,106 variables, the test-set coefficient of determination (R2) from the best performing models ranged between 0.184-0.782. The adjusted R2 values from multiple linear regression models ranged from 0.311-0.8293. Relative contribution of consumer expenditures to model fit ranged from 23.4-33.6%. DISCUSSION: Machine learning models predicted RIHC among HSAs using diverse population data, including novel consumer expenditures and provides an innovative tool to predict population-based healthcare utilization and expenditures. Geographic variation in utilization and spending were identified.

Adaptation of an NLP system to a new healthcare environment to identify social determinants of health.

Social determinants of health (SDoH) are increasingly important factors for population health, healthcare outcomes, and care delivery. However, many of these factors are not reliably captured within structured electronic health record (EHR) data. In this work, we evaluated and adapted a previously published NLP tool to include additional social risk factors for deployment at Vanderbilt University Medical Center in an Acute Myocardial Infarction cohort. We developed a transformation of the SDoH outputs of the tool into the OMOP common data model (CDM) for re-use across many potential use cases, yielding performance measures across 8 SDoH classes of precision 0.83 recall 0.74 and F-measure of 0.78.

Cardiology providers' recommendations for treatments and use of patient decision aids for multivessel coronary artery disease.

BACKGROUND: Rates of recommending percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) vary across clinicians. Whether clinicians agree on preferred treatment options for multivessel coronary artery disease patients has not been well studied. METHODS AND RESULTS: We distributed a survey to 104 clinicians from the Northern New England Cardiovascular Study Group through email and at a regional meeting with 88 (84.6%) responses. The survey described three clinical vignettes of multivessel coronary artery disease patients. For each patient vignette participants selected appropriate treatment options and whether they would use a patient decision aid. The likelihood of choosing PCI only or PCI/CABG over CABG only was modeled using a multinomial regression. Across all vignettes, participants selected CABG only as an appropriate treatment option 24.2% of the time, PCI only 25.4% of the time, and both CABG or PCI as appropriate treatment options 50.4% of the time. Surgeons were less likely to choose PCI over CABG (RR 0.14, 95% CI 0.03, 0.59) or both treatments over CABG only (RR 0.10, 95% CI 0.03, 0.34) relative to cardiologists. Overall, 65% of participants responded they would use a patient decision aid with each vignette. CONCLUSIONS: There is a lack of consensus on the appropriate treatment options across cardiologists and surgeons for patients with multivessel coronary artery disease. Treatment choice is influenced by both patient characteristics and clinician specialty.

Improving the prediction of long-term readmission and mortality using a novel biomarker panel.

OBJECTIVE: Several short-term readmission and mortality prediction models have been developed using clinical risk factors or biomarkers among patients undergoing coronary artery bypass graft (CABG) surgery. The use of biomarkers for long-term prediction of readmission and mortality is less well understood. Given the established association of cardiac biomarkers with short-term adverse outcomes, we hypothesized that 5-year prediction of readmission or mortality may be significantly improved using cardiac biomarkers. MATERIALS AND METHODS: Plasma biomarkers from 1149 patients discharged alive after isolated CABG surgery from eight medical centers were measured in a cohort from the Northern New England Cardiovascular Disease Study Group between 2004 and 2007. We assessed the added predictive value of a biomarker panel with a clinical model against the clinical model alone and compared the model discrimination using the area under the receiver operating characteristic (AUROC) curves. RESULTS: In our cohort, 461 (40%) patients were readmitted or died within 5 years. Long-term outcomes were predicted by applying the STS ASCERT clinical model with an AUROC of 0.69. The biomarker panel with the clinical model resulted in a significantly improved AUROC of 0.74 (p value <.0001). Across 5 years, the hazard ratio for patients in the second to fifth quintile predicted probabilities from the biomarker augmented STS ASCERT model ranged from 2.2 to 7.9 (p values <.001). CONCLUSIONS: We report that a panel of biomarkers significantly improved prediction of long-term readmission or mortality risk following CABG surgery. Our findings suggest biomarkers help clinical care teams better assess the long-term risk of readmission or mortality.

Association of plasma-soluble ST2 and galectin-3 with cardiovascular events and mortality following cardiac surgery.

BACKGROUND: Cardiac surgery induces hemodynamic stress on the myocardium, and this process can be associated with significant post-operative morbidity and mortality. Soluble suppression of tumorigenicity 2 (sST2) and galectin-3 (gal-3) are biomarkers of myocardial remodeling and fibrosis; however, their potential association with post-operative changes is unknown. METHODS: We measured peri-operative plasma sST2 and gal-3 levels in two prospective cohorts (TRIBE-AKI and NNE) of over 1800 patients who underwent cardiac surgery. sST2 and gal-3 levels were evaluated for association with a composite primary outcome of cardiovascular event or mortality over median follow-up periods of 3.4 and 6.0 years, respectively, for the two cohorts. Meta-analysis of hazard ratio estimates from the cohorts was performed using random effects models. RESULTS: Cohorts demonstrated event rates of 70.2 and 66.8 per 1000 person-years for the primary composite outcome. After adjustment for clinical covariates, higher post-operative sST2 and gal-3 levels were significantly associated with cardiovascular event or mortality [pooled estimate HRs: sST2 1.29 (95% CI 1.16, 1.44); gal-3 1.26 (95% CI 1.09, 1.46)]. These associations were not significantly modified by pre-operative congestive heart failure or AKI. CONCLUSIONS: Higher post-operative sST2 and gal-3 values were associated with increased incidence of cardiovascular event or mortality. These two biomarkers should be further studied for potential clinical utility for patients undergoing cardiac surgery.

Perioperative COVID-19 Defense: An Evidence-Based Approach for Optimization of Infection Control and Operating Room Management.

We describe an evidence-based approach for optimization of infection control and operating room management during the coronavirus disease 2019 (COVID-19) pandemic. Confirmed modes of viral transmission are primarily, but not exclusively, contact with contaminated environmental surfaces and aerosolization. Evidence-based improvement strategies for attenuation of residual environmental contamination involve a combination of deep cleaning with surface disinfectants and ultraviolet light (UV-C). (1) Place alcohol-based hand rubs on the intravenous (IV) pole to the left of the provider. Double glove during induction. (2) Place a wire basket lined with a zip closure plastic bag on the IV pole to the right of the provider. Place all contaminated instruments in the bag (eg, laryngoscope blades and handles) and close. Designate and maintain clean and dirty areas. After induction of anesthesia, wipe down all equipment and surfaces with disinfection wipes that contain a quaternary ammonium compound and alcohol. Use a top-down cleaning sequence adequate to reduce bioburden. Treat operating rooms using UV-C. (3) Decolonize patients using preprocedural chlorhexidine wipes, 2 doses of nasal povidone-iodine within 1 hour of incision, and chlorhexidine mouth rinse. (4) Create a closed lumen IV system and use hub disinfection. (5) Provide data feedback by surveillance of Enterococcus, Staphylococcus aureus, Klebsiella, Acinetobacter, Pseudomonas, and Enterobacter spp. (ESKAPE) transmission. (6) To reduce the use of surgical masks and to reduce potential COVID-19 exposure, use relatively long (eg, 12 hours) staff shifts. If there are 8 essential cases to be done (each lasting 1-2 hours), the ideal solution is to have 2 teams complete the 8 cases, not 8 first case starts. (7) Do 1 case in each operating room daily, with terminal cleaning after each case including UV-C or equivalent. (8) Do not have patients go into a large, pooled phase I postanesthesia care unit because of the risk of contaminating facility at large along with many staff. Instead, have most patients recover in the room where they had surgery as is done routinely in Japan. These 8 programmatic recommendations stand on a substantial body of empirical evidence characterizing the epidemiology of perioperative transmission and infection development made possible by support from the Anesthesia Patient Safety Foundation (APSF).

Heart failure biomarker levels correlate with invasive haemodynamics in pulmonary valve replacement.

BACKGROUND: Although widely used in cardiology, relation of heart failure biomarkers to cardiac haemodynamics in patients with CHD (and in particular with pulmonary insufficiency undergoing pulmonary valve replacement) remains unclear. We hypothesised that the cardiac function biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP), soluble suppressor of tumorigenicity 2, and galectin-3 would have significant associations to right ventricular haemodynamic derangements. METHODS: Consecutive patients ( n = 16) undergoing cardiac catheterisation for transcatheter pulmonary valve replacement were studied. NT-proBNP, soluble suppressor of tumorigenicity 2, and galectin-3 levels were measured using a multiplex enzyme-linked immunosorbent assay from a pre-intervention blood sample obtained after sheath placement. Spearman correlation was used to identify significant correlations (p ≤ 0.05) of biomarkers with baseline cardiac haemodynamics. Cardiac MRI data (indexed right ventricular and left ventricular end-diastolic volumes and ejection fraction) prior to device placement were also compared to biomarker levels. RESULTS: NT-proBNP and soluble suppressor of tumorigenicity 2 were significantly correlated (p < 0.01) with baseline mean right atrial pressure and right ventricular end-diastolic pressure. Only NT-proBNP was significantly correlated with age. Galectin-3 did not have significant associations in this cohort. Cardiac MRI measures of right ventricular function and volume were not correlated to biomarker levels or right heart haemodynamics. CONCLUSIONS: NT-proBNP and soluble suppressor of tumorigenicity 2, biomarkers of myocardial strain, significantly correlated to invasive pressure haemodynamics in transcatheter pulmonary valve replacement patients. Serial determination of soluble suppressor of tumorigenicity 2, as it was not associated with age, may be superior to serial measurement of NT-proBNP as an indicator for timing of pulmonary valve replacement.

Claims-based surveillance for reintervention after endovascular aneurysm repair among non-Medicare patients.

OBJECTIVE: Many patients who undergo endovascular aortic aneurysm repair (EVR) also undergo repeat procedures, or reinterventions, to address suboptimal device performance and prevent aneurysm rupture. Quality improvement initiatives measuring reintervention after EVR has focused on fee-for-service Medicare patients. However, because patients aged less than 65 years and those with Medicare Advantage represent an important growing subgroup, we used a novel approach leveraging a state data source that captures patients of all ages and with all types of insurance. METHODS: We identified patients who underwent EVR (2011-2015) within the Vascular Quality Initiative registry and were also listed in the Statewide Planning and Research Cooperative System all-payer claims database of New York. We linked patients in the Vascular Quality Initiative to their Statewide Planning and Research Cooperative System claims file at the patient level with a 96% match rate. We compared outcomes between fee-for-service Medicare eligible, defined as age 65 or older or on dialysis, versus ineligible patients, defined as those younger than 65 and not on dialysis. Our primary outcome was reintervention. We used Cox proportional hazards regression and propensity score matching for risk adjustment. RESULTS: We studied 1285 patients with a median follow-up of 16 months (range, 1-57 months). The mean age was 74 years, 79% were male, and 84% of procedures were elective. Nearly one in six patients were not Medicare eligible (14%), and the remainder (86%) were Medicare eligible. Medicare-eligible patients were less likely to be male (77% vs 91%; P < .001), have a history of smoking (79% vs 93%; P < .001), and have a nonelective procedure (15% vs 23%; P = .013). The 3-year Kaplan-Meier rate of reintervention was 21%. We found similar rates of reintervention between Medicare-eligible patients and those who were not (19% vs 20%, log-rank P = .199; unadjusted hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.49-1.16). This finding persisted in both the adjusted and propensity-matched analyses (adjusted HR, 0.82; 95% CI, 0.50-1.34; propensity-matched HR, 0.70; 95% CI, 0.36-1.37). CONCLUSIONS: Reintervention can be monitored using administrative claims from both Medicare and non-Medicare payers, and serve as an important outcome metric after EVR in patients of all ages. The rate of reintervention seems to be similar between older, Medicare-eligible individuals, and those who are not yet eligible.

sST2 as a novel biomarker for the prediction of in-hospital mortality after coronary artery bypass grafting.

Objectives: Soluble suppression of tumorigenicity 2 (sST2) biomarker is an emerging predictor of adverse clinical outcomes, but its prognostic value for in-hospital mortality after coronary artery bypass grafting (CABG) is not well understood. This study measured the association between operative sST2 levels and in-hospital mortality after CABG. Methods: A prospective cohort of 1560 CABG patients were analyzed from the Northern New England Cardiovascular Disease Study Group Biomarker Study. The primary outcome was in-hospital mortality after CABG surgery (n = 32). Results: After risk adjustment, patients in the third tercile of pre-, post- and pre-to-postoperative sST2 values experienced significantly greater odds of in-hospital death compared to patients in the first tercile of sST2 values. The addition of both postoperative and pre-to-postoperative sST2 biomarker significantly improved ability to predict in-hospital mortality status following CABG surgery, compared to using the EuroSCORE II mortality model alone, (c-statistic: 0.83 [95% CI: 0.75, 0.92], p value 0.0213) and (c-statistic: 0.83 [95% CI: 0.75, 0.92], p value 0.0215), respectively. Conclusion: sST2 values are associated with in-hospital mortality after CABG surgery and postoperative and pre-to-post operative sST2 values improve prediction. Our findings suggest that sST2 can be used as a biomarker to identify adult patients at greatest risk of in-hospital death after CABG surgery.

Healthcare spending in the State of Louisiana.

BACKGROUND: The State of Louisiana spends the most on Medicare beneficiaries per capita, but reports greater disparities in health status and death rates than other states. This project sought to investigate the associations between healthcare intensity, healthcare spending, and mortality in Louisiana. METHODS: We used a 100% sample of 2014 Medicare claims data with beneficiaries assigned to hospital referral regions in Louisiana using small area analysis. We used simple and multivariable linear regression modelling to evaluate associations between healthcare intensity, healthcare spending rates, and mortality rates. We adjusted for age, sex, race, and population health risk factors. RESULTS: We found no statistically significant associations between our measured variables when adjusted for age, sex, and race. These results were consistent after further adjusting mortality for population health risk factors. CONCLUSIONS: To our knowledge, no prior studies have investigated the associations between healthcare intensity, healthcare spending, and mortality in Louisiana. Our findings suggest that increased healthcare spending in Louisiana may not improve survival. Identifying more granular aspects of healthcare contributing to spending patterns in Louisiana may provide targets for future quality improvement work.

Biomarkers associated with 30-day readmission and mortality after pediatric congenital heart surgery.

OBJECTIVES: Novel cardiac biomarkers serum (suppression of tumorigenicity [ST2]) and Galectin-3 may be associated with an increased likelihood of important events after cardiac surgery. Our objective was to explore the association between pre- and postoperative serum biomarker levels and 30-day readmission or mortality for pediatric patients. METHODS: We prospectively enrolled pediatric patients <18 years of age who underwent at least one cardiac surgical operation at Johns Hopkins Children's Center from 2010 to 2014 (N = 162). Blood samples were collected immediately before surgery and at the end of bypass. We evaluated the association between pre- and postoperative Galectin-3 and ST2 with 30-day readmission or mortality, using backward stepwise logistic regression, adjusting for covariates based on the Society of Thoracic Surgeons (STS) Congenital Heart Surgery Mortality Risk Model. RESULTS: In our cohort, 21 (12.9%) patients experienced readmission or mortality 30-days from discharge. Before adjustment, preoperative ST2 terciles demonstrated a strong association with readmission and/or mortality after surgery (OR: 2.58; 95% CI: 1.17-3.66 and OR: 4.37; 95% CI: 1.31-14.57). After adjustment for covariates based on the STS congenital risk model, Galectin-3 postoperative mid-tercile was significantly associated with 30-day readmission or mortality (OR: 6.17; 95% CI: 1.50-0.43) as was the highest tercile of postoperative ST2 (OR: 4.98; 95% CI: 1.06-23.32). CONCLUSIONS: Elevated pre-and postoperative levels of ST2 and Galectin-3 are associated with increased risk of readmission or mortality after pediatric heart surgery. These clinically available biomarkers can be used for improved risk stratification and may guide improved patient care management.

A multi-center analysis of readmission after cardiac surgery: Experience of The Northern New England Cardiovascular Disease Study Group.

BACKGROUND: Readmissions after cardiac surgery are common and associated with increased morbidity, mortality and cost of care. Policymakers have targeted coronary artery bypass grafting to achieve value-oriented health care milestones. We explored the causes of readmission following cardiac surgery among a regional consortium of hospitals. METHODS: Using administrative data, we identified patients readmitted to the same institution within 30 days of cardiac surgery. We performed standardized review of readmitted patients' medical records to identify primary and secondary causes of readmission. We evaluated causes of readmission by procedure and tested for univariate associations between characteristics of readmitted patients and nonreadmitted patients in our clinical registry. RESULTS: Of 2218 cardiac surgery patients, 272 were readmitted to the index hospital within 30 days for a readmission rate of 12.3%. Median time to readmission was 9 days (interquartile range 4-16 days) and only 13% of patients were evaluated in-office before readmission. Readmitted patients were more likely to have had valve surgery (31.3% vs 22.7%) than patients not readmitted. Readmitted patients were also more likely to have preoperative creatinine more than or equal to 2 mg/dL (P = .015) or congestive heart failure (CHF) (P = .034), require multiple blood transfusions or sustained inotropic support (P < .001), and experience postoperative atrial fibrillation (P = .022) or renal insufficiency (P < .001). Infection (26%), pleural or pericardial effusion (19%), arrhythmia (16%), and CHF (11%) were the most common primary etiologies leading to readmission. CONCLUSIONS: Ensuring early follow-up for high-risk patient groups while improving early detection and management of the principal drivers of readmission represent promising targets for decreasing readmission rates.

Biomarkers improve prediction of 30-day unplanned readmission or mortality after paediatric congenital heart surgery.

OBJECTIVE: To evaluate the association between novel pre- and post-operative biomarker levels and 30-day unplanned readmission or mortality after paediatric congenital heart surgery. METHODS: Children aged 18 years or younger undergoing congenital heart surgery (n = 162) at Johns Hopkins Hospital from 2010 to 2014 were enrolled in the prospective cohort. Collected novel pre- and post-operative biomarkers include soluble suppression of tumorgenicity 2, galectin-3, N-terminal prohormone of brain natriuretic peptide, and glial fibrillary acidic protein. A model based on clinical variables from the Society of Thoracic Surgery database was developed and evaluated against two augmented models. RESULTS: Unplanned readmission or mortality within 30 days of cardiac surgery occurred among 21 (13%) children. The clinical model augmented with pre-operative biomarkers demonstrated a statistically significant improvement over the clinical model alone with a receiver-operating characteristics curve of 0.754 (95% confidence interval: 0.65-0.86) compared to 0.617 (95% confidence interval: 0.47-0.76; p-value: 0.012). The clinical model augmented with pre- and post-operative biomarkers demonstrated a significant improvement over the clinical model alone, with a receiver-operating characteristics curve of 0.802 (95% confidence interval: 0.72-0.89; p-value: 0.003). CONCLUSIONS: Novel biomarkers add significant predictive value when assessing the likelihood of unplanned readmission or mortality after paediatric congenital heart surgery. Further exploration of the utility of these novel biomarkers during the pre- or post-operative period to identify early risk of mortality or readmission will aid in determining the clinical utility and application of these biomarkers into routine risk assessment.

The Association between Cytokines and 365-Day Readmission or Mortality in Adult Cardiac Surgery.

Cardiac surgery results in a multifactorial systemic inflammatory response with inflammatory cytokines, such as interleukin-10 and 6 (IL-10 and IL-6), shown to have potential in the prediction of adverse outcomes including readmission or mortality. This study sought to measure the association between IL-6 and IL-10 levels and 1-year hospital readmission or mortality following cardiac surgery. Plasma biomarkers IL-6 and IL-10 were measured in 1,047 patients discharged alive after isolated coronary artery bypass graft surgery from eight medical centers participating in the Northern New England Cardiovascular Disease Study Group between 2004 and 2007. Readmission status and mortality were ascertained using Medicare, state all-payer claims, and the National Death Index. We evaluated the association between preoperative and postoperative cytokines and 1-year readmission or mortality using Kaplan-Meier estimates and Cox's proportional hazards modeling, adjusting for covariates used in the Society of Thoracic Surgeons 30-day readmission model. The median follow-up time was 1 year. After adjustment, patients in the highest tertile of postoperative IL-6 values had a significantly increased risk of readmission or death within 1 year (HR: 1.38; 95% CI: 1.03-1.85), and an increased risk of death within 1 year of discharge (HR: 4.88; 95% CI: 1.26-18.85) compared with patients in the lowest tertile. However, postoperative IL-10 levels, although increasing through tertiles, were not found to be significantly associated independently with 1-year readmission or mortality (HR: 1.25; 95% CI: .93-1.69). Pro-inflammatory cytokine IL-6 and anti-inflammatory cytokine IL-10 may be postoperative markers of cardiac injury, and IL-6, specifically, shows promise in predicting readmission and mortality following cardiac surgery.

Maximum allowable contrast dose and prevention of acute kidney injury following cardiovascular procedures.

PURPOSE OF REVIEW: Contrast-induced acute kidney injury (CI-AKI) is a serious complication. Although nonmodifiable and modifiable risk factors have been thoroughly characterized, the utility of the maximal allowable contrast dose (MACD) has not received adequate attention. The focus of this review is to provide a critical appraisal of this modifiable risk factor. RECENT FINDINGS: Several retrospective and prospective cohort studies have demonstrated that the incidence of CI-AKI among patients receiving contrast media in volumes exceeding the MACD is consistently higher compared with those who do not exceed the MACD (an average of 24 vs. 6%). Furthermore, the MACD is independent predictor of CI-AKI and other adverse events. A two-step algorithm incorporating the determination of the MACD and the contrast volume to eGFR ratio prior to a planned cardiovascular procedure is a sound approach to minimize contrast volume and prevent CI-AKI. SUMMARY: Prevention of CI-AKI must remain a clinical priority. Intraprocedural preventive measures should include a priori calculation of the MACD and contrast volume to eGFR ratio to limit contrast volume. Other measures may include the adoption of the transradial approach, the use of automated contrast injectors and small catheters to limit contrast volume, the use of low-osmolar contrast agents, and if necessary the use of staged procedures. We call for the system-wide implementation of evidence-based care bundles to prevent CI-AKI.