Activity-based cost analysis of laboratory tests in clinical chemistry.

OJECTIVES: Since health care budgets are limited and must be allocated efficiently, there is an economic pressure to reduce the costs of health care interventions. This study aims to investigate the cost of testing within a Clinical Chemistry laboratory. METHODS: This study was conducted in the Clinical Chemistry laboratory of the University Hospital UZ Brussel, Belgium, in which 156 tests were included and an average cost per test was calculated for the year 2018. Activity-based costing (ABC) was applied, using a top-down perspective. Costs were first allocated to different activity centers and subsequently to different tests. Number of tests, parameters, analyzers and time estimates were used as activity cost drivers. RESULTS: The blood glucose test on the point-of-care testing (POCT) analyzer Accu Chek Inform II had the lowest unit cost (€0.92). The determination of methanol, ethanol and isopropanol on the GC-FID (7820A) is the test with the highest unit cost (€129.42). In terms of average cost per test per activity center, core laboratory (€3.37) scored lowest, followed consecutively by POCT (€3.49), diabetes (€22.09), toxicology (€31.52), metabolic disorder (€41.53) and cystic fibrosis (€86.02). The cost per test was mainly determined by staff (57%), costs of support services (23%) and reagents (14%). CONCLUSIONS: High-volume and automated tests have lower unit costs, as is the case with the core laboratory. ABC provides the ability to identify high average cost tests that can benefit from optimizations, such as focusing on automation or outsourcing low-volume tests that can benefit from economies of scale.

Exercise-induced biphasic increase in circulating NT-proBNP levels in patients with chronic heart failure.

BACKGROUND: Exercise increases natriuretic peptide levels in chronic heart failure (CHF) patients, but the effect is considered minor. We assessed acute and short-term release (<24 h) of NT-proBNP in CHF patients after a maximal cardiopulmonary exercise test (CPET) and 2 different submaximal training sessions. METHODS AND RESULTS: 102 CHF patients either performed CPET (Group 1), a 1 h endurance (Group 2) or a combined endurance-resistance training session (Group 3). NT-proBNP concentration was determined before, at exercise cessation and after 18-22 h (Protocol A). In 20 patients, samples were obtained before, at exercise cessation, after 15, 30, 45, 60, 90 min, 2, 3, 4, 5, 6, 12, 22 h (Protocol B). Protocol A: At peak exercise, a 15%, 11% and 17% relative increase (p<0.001 vs baseline, all 3 groups) was seen, with a return to baseline after 18-22 h. The increase correlated with indicators of more advanced heart failure. Protocol B: A biphasic pattern was derived with a first peak within 1 h of exercise termination and a second peak (39%, 31% and 33% higher than baseline; p<0.05, all 3 groups) after 4-12 h. CONCLUSIONS: The observed biphasic release of B-type natriuretic peptides supports standardization of sampling, taking recent exercise into account.

Cystic Lymphangioma: Are Triglycerides Always Measurable?

The presence of chylous fluid with high triglycerides levels on endoscopic ultrasound- (EUS-) guided fine needle aspiration (FNA) is very pathognomonic for the diagnosis of cystic lymphangiomas of the pancreas. In our case report the puncture of the pancreatic cyst showed a typical milky fluid though measurable triglyceride concentrations were absent in the laboratory. Two possible explanations were found. First of all grossly lipemic samples show a slower rate of color development than do clear serums which can produce a false negative result if the sample is insufficiently diluted. Secondly, high lipase levels can divide triglycerides in glycerol and fatty acids, making the concentration of triglycerides undetectable.

Combined endurance/resistance training reduces NT-proBNP levels in patients with chronic heart failure.

AIMS: This study was designed to evaluate the effects of combined endurance/resistance training on NT-proBNP levels in patients with chronic heart failure (CHF). The safety of resistive weight training for patients with CHF is questioned. Possible detrimental effects include an increase in ventricular diastolic pressure and secondary unfavourable remodelling. Circulating levels of the N-terminal fragment of brain natriuretic peptide (NT-proBNP) reflect left ventricular diastolic wall stress and are strongly related to mortality and treatment success in CHF. METHODS AND RESULTS: In this study, 27 consecutive patients with stable CHF and left ventricular ejection fraction (LVEF) <35% were enrolled in a 4 months non-randomized combined endurance/resistance training programme. Blood sampling for measurement of NT-proBNP, functional assessment, cardiopulmonary exercise testing, echocardiography and radionuclide angiography were performed at entry and after 4 months. After 4 months, exercise training caused a significant reduction in circulating concentrations of NT-proBNP (2124+/-397 pg/ml before, 1635+/-304 pg/ml after training, p=0.046, interaction), whereas no changes were observed in an untrained heart failure control group. NYHA functional class (p=0.02, interaction), maximal (peak VO2: p=0.035, interaction; maximal workload: p<0.00001, interaction) and submaximal (workload at anaerobic threshold: p=0.001, interaction; rate-pressure product at anaerobic threshold: p=0.001, interaction) exercise parameters as well as work efficiency (Wattmax/VO2peak: p=0.0001, interaction) were significantly improved. In addition, a decrease in left ventricular end-systolic diameter was observed in the trained heart failure group (p=0.016). CONCLUSION: Four months of combined endurance/resistance training significantly reduced circulating levels of NT-proBNP in patients with CHF, without evidence of adverse remodelling. Exercise training might offer additional non-pharmacological modulation of the activated neurohormonal pathways in the setting of CHF.