Incorporating Acute Conditions into Risk-Adjustment for Provider Profiling: The Case of the US News and World Report Best Hospitals Rankings Methodology.

Several years ago, the US News and World Report changed their risk-adjustment methodology, now relying almost exclusively on chronic conditions for risk adjustment. The impacts of adding selected acute conditions like pneumonia, sepsis, and electrolyte disorders ("augmented") to their current risk models ("base") for 4 specialties-cardiology, neurology, oncology, and pulmonology-on estimates of hospital performance are reported here. In the augmented models, many acute conditions were associated with substantial risks of mortality. Compared to the base models, the discrimination and calibration of the augmented models for all specialties were improved. While estimated hospital performance was highly correlated between the 2 models, the inclusion of acute conditions in risk-adjustment models meaningfully improved the predictive ability of those models and had noticeable effects on hospital performance estimates. Measures or conditions that address disease severity should always be included when risk-adjusting hospitalization outcomes, especially if the goal is provider profiling.

Building the pipeline: the creation of a residency training pathway for future physician leaders in health care quality.

PROBLEM: Many health care organizations seek physicians to lead quality improvement (QI) efforts, yet struggle to find individuals with the necessary expertise. Although most residency programs incorporate QI and patient safety principles into their curricula, few provide a specialized training program for residents exploring careers as physician leaders in quality. APPROACH: Recognizing this training void, the authors designed and implemented the Healthcare Leadership in Quality (HLQ) track for residents at the University of Pennsylvania Health System in 2010. This longitudinal, two-year graduate medical education (GME) track aligns with the quality goals of the University of Pennsylvania Health System and includes a core curriculum, integration into an interprofessional health care leadership team that is accountable for quality and safety outcomes on a hospital unit, a capstone QI project, and mentorship. OUTCOMES: Early evaluation has demonstrated the feasibility and efficacy of the track diverse graduate medical education training programs. Using Yardley and Dornan's interpretation of the Kirkpatrick framework, the authors have demonstrated the track's impact on four levels of educational and organizational outcomes. NEXT STEPS: Building on their early experiences, the authors are integrating project and time management skills into the core curriculum, and they are focusing more effort on faculty development in QI mentorship. Additionally, the authors plan to follow HLQ track graduates to determine whether they seek leadership roles in quality and safety and to assess the influence of the program on their careers.

Mechanisms of type 2 diabetes resolution after Roux-en-Y gastric bypass.

BACKGROUND: Bariatric surgery is the most effective treatment for the reduction of weight and resolution of type 2 diabetes mellitus (T2 DM). The objective of this study was to longitudinally assess hormonal and tissue responses after RYGB. METHODS: Eight patients (5 with T2 DM) were studied before and after RYGB. A standardized test meal (STM) was administered before and at 1, 3, 6, 9, 12, and 15 months. Separately, a 2-hour hyperinsulinemic-euglycemic clamp (E-clamp) and a 2-hour hyperglycemic clamp (H-clamp) were performed before and at 1, 3, 6, and 12 months. Glucagon-like peptide-1 (GLP-1) was infused during the last hour of the H-clamp. Body composition was assessed with DXA methodology. RESULTS: Enrollment body mass index was 49±3 kg/m(2) (X±SE). STM glucose and insulin responses were normalized by 3 and 6 months. GLP-1 level increased dramatically at 1, 3, and 6 months, normalizing by 12 and 15 months. Insulin sensitivity (M of E-clamp) increased progressively at 3-12 months as fat mass decreased. The insulin response to glucose alone fell progressively over 12 months but the glucose clearance/metabolism (M of H-clamp) did not change significantly until 12 months. In response to GLP-1 infusion, insulin levels fell progressively throughout the 12 months. CONCLUSION: The early hypersecretion of GLP-1 leads to hyperinsulinemia and early normalization of glucose levels. The GLP-1 response normalizes within 1 year after surgery. Enhanced peripheral tissue sensitivity to insulin starts at 3 months and is associated with fat mass loss. ß-cell sensitivity improves at 12 months and after the loss of ≈33% of excess weight. There is a tightly controlled feedback loop between peripheral tissue sensitivity and ß-cell and L-cell (GLP-1) responses.

GLP-1 (7-36) amide restores myocardial insulin sensitivity and prevents the progression of heart failure in senescent beagles.

BACKGROUND: We previously demonstrated that older beagles have impaired whole body and myocardial insulin responsiveness (MIR), and that glucagon-like peptide-1 (GLP-1 [7-36] amide) improves MIR in young beagles with dilated cardiomyopathy (DCM). Here, we sought to determine if aging alone predisposes to an accelerated course of DCM, and if GLP-1 [7-36] amide would restore MIR and impact the course of DCM in older beagles. METHODS: Eight young beagles (Young-Control) and sixteen old beagles underwent chronic left ventricle (LV) instrumentation. Seven old beagles were treated with GLP-1 (7-36) amide (2.5 pmol/kg/min) for 2 weeks prior to instrumentation and for 35 days thereafter (Old + GLP-1), while other 9 served as control (Old-Control). All dogs underwent baseline metabolic determinations and LV biopsy for mitochondria isolation prior to the development of DCM induced by rapid pacing (240 min-1). Hemodynamic measurements were performed routinely as heart failure progressed. RESULTS: At baseline, all old beagles had elevated non-esterifed fatty acids (NEFA), and impaired MIR. GLP-1 reduced plasma NEFA (Old-Control: 853 ± 34; Old + GLP-1: 531 ± 33 µmol/L, p < 0.02), improved MIR (Old-Control: 289 ± 54; Old + GLP-1: 512 ± 44 mg/min/100 mg, p < 0.05), and increased uncoupling protein-3 (UCP-3) expression in isolated mitochondria. Compared to the Young-Control, the Old-Controls experienced an accelerated course of DCM (7 days versus 29 days, p < 0.005) and excess mortality, while the Old + GLP-1 experienced increased latency to the onset of DCM (7 days versus 23 days, p < 0.005) and reduced mortality. CONCLUSION: Aging is associated with myocardial insulin resistance, which predispose to an accelerated course of DCM. GLP-1 treatment is associated with increased MIR and protection against an accelerated course of DCM in older beagles.

Beyond glycemic control: cardiovascular effects of incretin-based therapies.

As cardiovascular (CV) disease remains the major cause of mortality and morbidity in type 2 diabetes mellitus, reducing macrovascular complications has been a major target of antiglycemic therapies. Emerging evidence suggests that incretin-based therapies are safe and may provide CV and cerebrovascular (CBV) benefits beyond those attributable to glycemic control, making the class an attractive therapeutic option. However, the mechanisms whereby the various classes of incretin-based therapies exert CV and CBV benefits may be distinct and may not necessarily lead to similar outcomes. In this chapter, we will discuss the potential mechanisms and current understanding of CV and CBV benefits of native glucagon-like peptide (GLP)-1, GLP-1 receptor agonists and analogues, and of dipeptidyl peptidase-4 inhibitor therapies as a means to better understand differences in safety and efficacy.

GLP-1(32-36)amide, a novel pentapeptide cleavage product of GLP-1, modulates whole body glucose metabolism in dogs.

We have previously demonstrated in human subjects who under euglycemic clamp conditions GLP-1(9-36)amide infusions inhibit endogenous glucose production without substantial insulinotropic effects. An earlier report indicates that GLP-1(9-36)amide is cleaved to a nonapeptide, GLP-1(28-36)amide and a pentapeptide GLP-1(32-36)amide (LVKGR amide). Here we study the effects of the pentapeptide on whole body glucose disposal during hyperglycemic clamp studies. Five dogs underwent indwelling catheterizations. Following recovery, the dogs underwent a 180 min hyperglycemic clamp (basal glucose +98 mg/dl) in a cross-over design. Saline or pentapeptide (30 pmol kg(-1) min(-1)) was infused during the last 120 min after commencement of the hyperglycemic clamp in a primed continuous manner. During the last 30 min of the pentapeptide infusion, glucose utilization (M) significantly increased to 21.4±2.9 mg kg(-1) min(-1)compared to M of 14.3±1.1 mg kg(-1)min(-1) during the saline infusion (P=0.026, paired t-test; P=0.062, Mann-Whitney U test). During this interval, no significant differences in insulin (26.6±3.2 vs. 23.7±2.5 µU/ml, P=NS) or glucagon secretion (34.0±2.1 vs. 31.7±1.8 pg/ml, P=NS) were observed. These findings demonstrate that under hyperglycemic clamp studies the pentapeptide modulates glucose metabolism by a stimulation of whole-body glucose disposal. Further, the findings suggest that the metabolic benefits previously observed during GLP-1(9-36)amide infusions in humans might be due, at least in part, to the metabolic effects of the pentapeptide that is cleaved from the pro-peptide, GLP-1(9-36)amide in the circulation.

Patient-centered community health worker intervention to improve posthospital outcomes: a randomized clinical trial.

IMPORTANCE Socioeconomic and behavioral factors can negatively influence posthospital outcomes among patients of low socioeconomic status (SES). Traditional hospital personnel often lack the time, skills, and community linkages required to address these factors. OBJECTIVE To determine whether a tailored community health worker (CHW) intervention would improve posthospital outcomes among low-SES patients. DESIGN, SETTING, AND PARTICIPANTS A 2-armed, single-blind, randomized clinical trial was conducted between April 10, 2011, and October 30, 2012, at 2 urban, academically affiliated hospitals. Of 683 eligible general medical inpatients (ie, low-income, uninsured, or Medicaid) that we screened, 237 individuals (34.7%) declined to participate. The remaining 446 patients (65.3%) were enrolled and randomly assigned to study arms. Nearly equal percentages of control and intervention group patients completed the follow-up interview (86.6% vs 86.9%). INTERVENTIONS During hospital admission, CHWs worked with patients to create individualized action plans for achieving patients' stated goals for recovery. The CHWs provided support tailored to patient goals for a minimum of 2 weeks. MAIN OUTCOMES AND MEASURES The prespecified primary outcome was completion of primary care follow-up within 14 days of discharge. Prespecified secondary outcomes were quality of discharge communication, self-rated health, satisfaction, patient activation, medication adherence, and 30-day readmission rates. RESULTS Using intention-to-treat analysis, we found that intervention patients were more likely to obtain timely posthospital primary care (60.0% vs 47.9%; P = .02; adjusted odds ratio [OR], 1.52; 95% CI, 1.03-2.23), to report high-quality discharge communication (91.3% vs 78.7%; P = .002; adjusted OR, 2.94; 95% CI, 1.5-5.8), and to show greater improvements in mental health (6.7 vs 4.5; P = .02) and patient activation (3.4 vs 1.6; P = .05). There were no significant differences between groups in physical health, satisfaction with medical care, or medication adherence. Similar proportions of patients in both arms experienced at least one 30-day readmission; however, intervention patients were less likely to have multiple 30-day readmissions (2.3% vs 5.5%; P = .08; adjusted OR, 0.40; 95% CI, 0.14-1.06). Among the subgroup of 63 readmitted patients, recurrent readmission was reduced from 40.0% vs 15.2% (P = .03; adjusted OR, 0.27; 95% CI, 0.08-0.89). CONCLUSIONS AND RELEVANCE Patient-centered CHW intervention improves access to primary care and quality of discharge while controlling recurrent readmissions in a high-risk population. Health systems may leverage the CHW workforce to improve posthospital outcomes by addressing behavioral and socioeconomic drivers of disease. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01346462.

The glucoregulatory benefits of glucagon-like peptide-1 (7-36) amide infusion during intensive insulin therapy in critically ill surgical patients: a pilot study.

OBJECTIVES: Intensive insulin therapy for tight glycemic control in critically ill surgical patients has been shown to reduce mortality; however, intensive insulin therapy is associated with iatrogenic hypoglycemia and increased variability of blood glucose levels. The incretin glucagon-like peptide-1 (7-36) amide is both insulinotropic and insulinomimetic and has been suggested as an adjunct to improve glycemic control in critically ill patients. We hypothesized that the addition of continuous infusion of glucagon-like peptide-1 to intensive insulin therapy would result in better glucose control, reduced requirement of exogenous insulin administration, and fewer hypoglycemic events. DESIGN: Prospective, randomized, double-blind, placebo-controlled clinical trial. SETTING: Surgical or burn ICU. PATIENTS: Eighteen patients who required intensive insulin therapy. INTERVENTIONS: A 72-hour continuous infusion of either glucagon-like peptide-1 (1.5 pmol/kg/min) or normal saline plus intensive insulin therapy. MEASUREMENTS AND MAIN RESULTS: The glucagon-like peptide-1 cohort (n = 9) and saline cohort (n = 9) were similar in age, Acute Physiology and Chronic Health Evaluation score, and history of diabetes. Blood glucose levels in the glucagon-like peptide-1 group were better controlled with much less variability. The coefficient of variation of blood glucose ranged from 7.2% to 30.4% in the glucagon-like peptide-1 group and from 19.8% to 56.8% in saline group. The mean blood glucose coefficient of variation for the glucagon-like peptide-1 and saline groups was 18.0% ± 2.7% and 30.3% ± 4.0% (p = 0.010), respectively. The 72-hour average insulin infusion rates were 3.37 ± 0.61 and 4.57 ± 1.18 U/hr (p = not significant). The incidents of hypoglycemia (≤ 2.78 mmol/L) in both groups were low (one in the glucagon-like peptide-1 group, three in the saline group). CONCLUSIONS: Glucagon-like peptide-1 (7-36) amide is a safe and efficacious form of adjunct therapy in patients with hyperglycemia in the surgical ICU setting. Improved stability of blood glucose is a favorable outcome, which enhances the safety of intensive insulin therapy. Larger studies of this potentially valuable therapy for glycemic control in the ICU are justified.

Incretin-based therapies: can we achieve glycemic control and cardioprotection?

Glucagon-like (GLP-1) is a peptide hormone secreted from the small intestine in response to nutrient ingestion. GLP-1 stimulates insulin secretion in a glucose-dependent manner, inhibits glucagon secretion and gastric emptying, and reduces appetite. Because of the short circulating half-life of the native GLP-1, novel GLP-1 receptor (GLP-1R) agonists and analogs and dipeptidyl peptidase 4 (DPP-4) inhibitors have been developed to facilitate clinical use. Emerging evidence indicates that GLP-1-based therapies are safe and may provide cardiovascular (CV) benefits beyond glycemic control. Preclinical and clinical studies are providing increasing evidence that GLP-1 therapies may positively affect CV function and metabolism by salutary effects on CV risk factors as well as via direct cardioprotective actions. However, the mechanisms whereby the various classes of incretin-based therapies exert CV effects may be mechanistically distinct and may not necessarily lead to similar CV outcomes. In this review, we will discuss the potential mechanisms and current understanding of CV benefits of native GLP-1, GLP-1R agonists and analogs, and of DPP-4 inhibitor therapies as a means to compare their putative CV benefits.

Chasing high performance: best business practices for using health information technology to advance patient safety.

The emergence of information technology in healthcare holds the promise to transform the industry through the creation of highly reliable information exchange. These same technologies have a central role in the patient safety movement. Organizations that wish to deliver safe and high-quality healthcare will only be successful if they plan, develop, and use health information systems with the principles of high-performing organizations in mind. We discuss the current state of health information technology in the patient safety movement, how this technology can contribute to high organizational performance, and some caveats.

Influence of renal dysfunction phenotype on mortality in the setting of cardiac dysfunction: analysis of three randomized controlled trials.

AIMS: Renal neurohormonal activation leading to a reduction in glomerular filtration rate (GFR) has been suggested as a mechanism for renal insufficiency (RI) in the setting of heart failure. We hypothesized that RI occurring in the presence of renal neurohormonal activation may be prognostically more important than RI in the absence of renal neurohormonal activation. METHODS AND RESULTS: Subjects in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial (n = 429), Beta-Blocker Evaluation of Survival Trial (BEST) (n = 2691), and Studies Of Left Ventricular Dysfunction (SOLVD) trial (n = 6782) limited datasets were studied. The blood urea nitrogen to creatinine ratio (BUN/Creatinine) was employed as a surrogate for renal neurohormonal activation and the primary outcome was the interaction between BUN/Creatinine and RI associated mortality. Baseline RI (GFR < 60 mL/min/1.73 m²) was associated with mortality in all study populations (P < 0.001). In patients with higher BUN/Creatinine, the risk of mortality was consistently greater in patients with RI [adjusted hazard ratio (HR) ESCAPE = 2.8, 95% confidence interval (CI) 1.3-14.3, P = 0.019; BEST = 1.6, 95% CI 1.2-2.2, P = 0.002; SOLVD = 1.6, 95% CI 1.3-2.0, P = 0.001]. However, in patients with lower BUN/Creatinine, the risk of mortality was not elevated in patients with RI (adjusted HR ESCAPE = 0.94, 95% CI 0.35-2.4, P = 0.90, P interaction = 0.005; BEST = 0.97, 95% CI 0.64-1.4, P = 0.90, P interaction = 0.02; SOLVD = 1.0, 95% CI 0.8-1.3, P = 0.71, P interaction = 0.005). CONCLUSION: The association between RI and poor survival observed in heart failure populations appears to be contingent not simply on the presence of a reduced GFR, but possibly on the mechanism by which GFR is reduced.

Interaction between loop diuretic-associated mortality and blood urea nitrogen concentration in chronic heart failure.

OBJECTIVES: The purpose of this study was to investigate whether a surrogate for renal neurohormonal activation, blood urea nitrogen (BUN), could identify patients destined to experience adverse outcomes associated with the use of high-dose loop diuretics (HDLD). BACKGROUND: Loop diuretics are commonly used to control congestive symptoms in heart failure; however, these agents cause neurohormonal activation and have been associated with worsened survival. METHODS: Subjects in the BEST (Beta-Blocker Evaluation of Survival Trial) receiving loop diuretics at baseline were analyzed (N = 2,456). The primary outcome was the interaction between BUN- and HDLD-associated mortality. RESULTS: In the overall cohort, HDLD use (≥160 mg/day) was associated with increased mortality (hazard ratio [HR]: 1.56; 95% confidence interval [CI]: 1.35 to 1.80). However, after extensively controlling for baseline characteristics, this association did not persist (HR: 1.06; 95% CI: 0.89 to 1.25). In subjects with BUN levels above the median (21.0 mg/dl), both the unadjusted (HR: 1.59; 95% CI: 1.34 to 1.88) and adjusted (HR: 1.29; 95% CI: 1.07 to 1.60) risk of death was higher in the HDLD group. In patients with BUN levels below the median, there was no associated risk with HDLD (HR: 0.99; 95% CI: 0.75 to 1.34) and after controlling for baseline characteristics, the HDLD group had significantly improved survival (HR: 0.71; 95% CI: 0.49 to 0.96) (p interaction = 0.018). CONCLUSIONS: The risk associated with HDLD use is strongly dependent on BUN concentrations with reduced survival in patients with an elevated BUN level and improved survival in patients with a normal BUN level. These data suggest a role for neurohormonal activation in loop diuretic-associated mortality.

Eliminating hospital acquired infections: is it possible? Is it sustainable? Is it worth it?

An estimated 2 million hospital-acquired infections (HAI) are now reported annually in the US, and are associated with an estimated $5 billion in additional health care costs. With this, the growing incidence of HAI has become "ground zero" in the campaign to improve patient safety and eliminate waste in health care.We studied the characteristics of high-performing organizations and their leaders outside of health care to determine how such organizations become "best in class." We then sought to apply the principles that led to this status to eliminating HAI associated with central venous catheters.Observations of the current condition of health care revealed multiple defects in various processes, that were breeding grounds for error. Redesign of these processes by the people involved in them under the guidance of a leader resulted in an 86% reduction in infections in the blood. Overall, financial performance improved by $5.1 million over a 2-year period. Mortality in intensive care units declined by 29%.Using methods borrowed from highly reliable industries and engaging workers at the point of care can have profound and sustainable effects in nearly eliminating HAI, with significant clinical and financial benefits.

Impact of changes in blood pressure during the treatment of acute decompensated heart failure on renal and clinical outcomes.

AIMS: One of the primary determinants of blood flow in regional vascular beds is perfusion pressure. Our aim was to investigate if reduction in blood pressure during the treatment of decompensated heart failure would be associated with worsening renal function (WRF). Our secondary aim was to evaluate the prognostic significance of this potentially treatment-induced form of WRF. METHODS AND RESULTS: Subjects included in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial limited data were studied (386 patients). Reduction in systolic blood pressure (SBP) was greater in patients experiencing WRF (-10.3 ± 18.5 vs. -2.8 ± 16.0 mmHg, P < 0.001) with larger reductions associated with greater odds for WRF (odds ratio = 1.3 per 10 mmHg reduction, P < 0.001). Systolic blood pressure reduction (relative change > median) was associated with greater doses of in-hospital oral vasodilators (P ≤ 0.017), thiazide diuretic use (P = 0.035), and greater weight reduction (P = 0.023). In patients with SBP-reduction, WRF was not associated with worsened survival [adjusted hazard ratio (HR) = 0.76, P = 0.58]. However, in patients without SBP-reduction, WRF was strongly associated with increased mortality (adjusted HR = 5.3, P < 0.001, P interaction = 0.001). CONCLUSION: During the treatment of decompensated heart failure, significant blood pressure reduction is strongly associated with WRF. However, WRF that occurs in the setting of SBP-reduction is not associated with an adverse prognosis, whereas WRF in the absence of this provocation is strongly associated with increased mortality. These data suggest that WRF may represent the final common pathway of several mechanistically distinct processes, each with potentially different prognostic implications.

Use of benchmarking and public reporting for infection control in four high-income countries.

Benchmarking of surveillance data for health-care-associated infection (HCAI) has been used for more than three decades to inform prevention strategies and improve patients' safety. In recent years, public reporting of HCAI indicators has been mandated in several countries because of an increasing demand for transparency, although many methodological issues surrounding benchmarking remain unresolved and are highly debated. In this Review, we describe developments in benchmarking and public reporting of HCAI indicators in England, France, Germany, and the USA. Although benchmarking networks in these countries are derived from a common model and use similar methods, approaches to public reporting have been more diverse. The USA and England have predominantly focused on reporting of infection rates, whereas France has put emphasis on process and structure indicators. In Germany, HCAI indicators of individual institutions are treated confidentially and are not disseminated publicly. Although evidence for a direct effect of public reporting of indicators alone on incidence of HCAIs is weak at present, it has been associated with substantial organisational change. An opportunity now exists to learn from the different strategies that have been adopted.

Impact of worsening renal function during the treatment of decompensated heart failure on changes in renal function during subsequent hospitalization.

BACKGROUND: Worsening renal function (WRF) commonly complicates the treatment of acute decompensated heart failure. Despite considerable investigation in this area, it remains unclear to what degree WRF is a reflection of treatment- versus patient-related factors. We hypothesized that if WRF is significantly influenced by factors intrinsic to the patient, then WRF during an index hospitalization should predict WRF during subsequent hospitalization. METHODS: Consecutive admissions to the Hospital of the University of Pennsylvania with a discharge diagnosis of congestive heart failure were reviewed. Patients with >1 hospitalization were retained for analysis. RESULTS: In total, 181 hospitalization pairs met the inclusion criteria. Baseline patient characteristics demonstrated significant correlation between hospitalizations (P ≤ .002 for all) but minimal association with WRF. In contrast, variables related to the aggressiveness of diuresis were weakly correlated between hospitalizations but significantly associated with WRF (P ≤ .024 for all). Consistent with the primary hypothesis, WRF during the index hospitalization was strongly associated with WRF during subsequent hospitalization (odds ratio [OR] 2.7, P = .003). This association was minimally altered after controlling for traditional baseline characteristics (OR 2.5, P = .006) and in-hospital treatment-related parameters (OR 2.8, P = .005). CONCLUSIONS: A prior history of WRF is strongly associated with subsequent episodes of WRF, independent of in-hospital treatment received. These results suggest that baseline factors intrinsic to the patient's cardiorenal pathophysiology have substantial influence on the subsequent development of WRF.

Characteristics of patients with improvement or worsening in renal function during treatment of acute decompensated heart failure.

Worsening renal function (RF) and improved RF during the treatment of decompensated heart failure have traditionally been thought of as hemodynamically distinct events. We hypothesized that if the pulmonary artery catheter-derived measures are relevant in the evaluation of cardiorenal interactions, the comparison of patients with improved versus worsening RF should highlight any important hemodynamic differences. All subjects in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness trial limited data set with admission and discharge creatinine values available were included (n = 401). No differences were found in the baseline, final, or change in pulmonary artery catheter-derived hemodynamic variables, inotrope and intravenous vasodilator use, or survival between patients with improved versus worsening RF (p = NS for all). Both groups were equally likely to be in the bottom quartile of cardiac index (p = 0.32), have a 25% improvement in cardiac index (p = 0.97), or have any worsening in cardiac index (p = 0.90). When patients with any significant change in renal function (positive or negative) were compared to those with stable renal function, strong associations between variables such as a reduced cardiac index (odds ratio 2.2, p = 0.02), increased intravenous inotrope and vasodilator use (odds ratio 2.9, p <0.001), and worsened all-cause mortality (hazard ratio 1.8, p = 0.01) became apparent. In contrast to traditionally held views, the patients with improved RF and those with worsening RF had similar hemodynamic parameters and outcomes. Combining these groups identified a hemodynamically compromised population with significantly worse survival than patients with stable renal function. In conclusion, the changes in renal function, regardless of the direction, likely identify a population with an advanced disease state and a poor prognosis.

Accuracy and reliability of the Nova StatStrip® glucose meter for real-time blood glucose determinations during glucose clamp studies.

AIMS/HYPOTHESIS: The Andres clamp technique, which requires accurate and timely determination of glucose, utilizes the Beckman or Yellow Springs Instruments (YSI) glucose analyzers. Both instruments require maintenance, a dedicated operator, preparation of a plasma sample, and a duplicate measurement that takes ≥2 minutes. The Nova StatStrip glucose meter was evaluated for accuracy, reliability, and near-real-time availability of glucose. METHODS: Blood samples from 24 patients who underwent 6-hour clamp studies and 12 patients who had a standardized meal tolerance test (SMT) were measured. Specimens were analyzed simultaneously and immediately upon collection by Beckman, YSI, and Nova. RESULTS: Of 1004 data pairs for the Nova device versus Beckman, the Nova data points ranged from 32 to 444, while Beckman ranged from 42 to 412. The coefficient for the slope of Beckman versus Nova was 1.009 (r = 0.978). Using error grid analysis, the number and percentage of values for Nova were 976 (97.2%) in the A zone and 28 (2.8%) in the B zone. Of 399 data pairs for the Nova device versus YSI, the Nova data points ranged from 46 to 255, whereas YSI ranged from 47 to 231. The coefficient for the slope of YSI versus Nova was 1.023 (r = 0.989). All Nova readings fell in the A zone. Time required for final reading, in duplicate, was 15 seconds for Nova and 120-180 seconds for Beckman and YSI. CONCLUSIONS: The simplicity of Nova and its reliability, accuracy, and speed make it an acceptable replacement device for Beckman and YSI in the conduct of clamps, especially when perturbations require rapid glucose determination.

Worsening renal function defined as an absolute increase in serum creatinine is a biased metric for the study of cardio-renal interactions.

OBJECTIVES: Worsening renal function (WRF) during the treatment of decompensated heart failure, frequently defined as an absolute increase in serum creatinine >or=0.3 mg/dl, has been reported as a strong adverse prognostic factor in several studies. We hypothesized that this definition of WRF is biased by baseline renal function secondary to the exponential relationship between creatinine and renal function. METHODS: We reviewed consecutive admissions with a discharge diagnosis of heart failure. An increase in creatinine >or=0.3 mg/dl (WRF(CREAT)) was compared to a decrease in GFR >or=20% (WRF(GFR)). RESULTS: Overall, 993 admissions met eligibility. WRF(CREAT) occurred in 31.5% and WRF(GFR) in 32.7%. WRF(CREAT) and WRF(GFR) had opposing relationships with baseline renal function (OR = 1.9 vs. OR = 0.51, respectively, p < 0.001). Both definitions had similar unadjusted associations with death at 30 days [WRF(GFR) OR = 2.3 (95% CI 1.1-4.8), p = 0.026; WRF(CREAT) OR = 2.1 (95% CI 1.0-4.4), p = 0.047]. Controlling for baseline renal insufficiency, WRF(GFR) added incrementally in the prediction of mortality (p = 0.009); however, WRF(CREAT) did not (p = 0.11). CONCLUSIONS: WRF, defined as an absolute change in serum creatinine, is heavily biased by baseline renal function. An alternative definition of WRF should be considered for future studies of cardio-renal interactions.