BACKGROUND: A handheld blood gas analyser has been newly developed for mobile monitoring of blood gasses and electrolytes. We evaluated the performance of a portable blood gas analyser, Epoc(TM) (Epocal Inc., Canada) according to Clinical and Laboratory Standard Institute (CLSI) guidelines, and compared it to that of a conventional analyser used in clinical laboratories. METHODS: Precision and percent carry-over were determined using three levels of aqueous and hematocrit control materials according to CLSI EP10-A3. Linearity was determined using five levels of control materials according to CLSI EP6-A. The pH, pCO2, pO2, Na+, K+, Ca2+, glucose, lactate, and hematocrit levels were compared between the Epoc(TM) and Stat Profile Critical Care Xpress (STP CCX; Nova Biomedical, USA) analysers using whole blood samples from 40 subjects according to CLSI EP9-A2. RESULTS: The coefficient of variation of the within-run precision and total precision were 0.000% to 4.563% and 0.000% to 5.298%, respectively. The carry-over was within 5%. The Epoc(TM) analyser showed excellent linearity for all nine parameters evaluated. For the comparison study, the Epoc(TM) and conventional analysers showed comparable results (correlation coefficient [r]=0.900-0.995), except for hematocrit (r=0.764). CONCLUSIONS: The Epoc(TM) POC analyser shows reliable analytical precision and is comparable to the traditional bench-top blood gas analysers. It could be useful in clinical settings, especially in operating rooms and pediatric intensive care units.
Blood Gas Analysis ; Critical Care ; Electrolytes ; Glucose ; Hematocrit ; Hydrogen-Ion Concentration ; Intensive Care Units, Pediatric ; Lactic Acid ; Operating Rooms ; Point-of-Care Systems

For the use of Indirect-conversion CMOS (complementary metal-oxide-semiconductor) detectors for digital x-ray radiography and their better designs, we have theoretically evaluated the spatial-frequency-dependent detective quantum efficiency (DQE) using the cascaded linear-systems transfer theory. In order to validate the developed model, the DQE was experimentally determined by the measured modulation-transfer function (MTF) and noise-power spectrum, and the estimated incident x-ray fluence under the mammography beam quality of W/Al. From the comparison between the theoretical and experimental DQEs, the overall tendencies were well agreed. Based on the developed model, we have investigated the DQEs values with respect to various design parameters of the CMOS x-ray detector such as phosphor quantum efficiency, Swank noise, photodiode quantum efficiency and the MTF of various scintillator screens. This theoretical approach is very useful tool for the understanding of the developed imaging systems as well as helpful for the better design or optimization for new development.
Mammography ; Noise ; Radiographic Image Enhancement

BACKGROUND: B-type natriuretic peptide (BNP) levels are elevated in various conditions unrelated to heart failure, such as acute coronary syndrome, and cardiac troponin (cTn) levels may also be elevated in several non-ischemic conditions. This study aimed to evaluate the clinical usefulness of combined cardiac marker testing (BNP and cTnI) with point-of-care devices in patients who presented to the emergency department (ED). METHODS: Two thousand six hundred and seventy-four consecutive patients who visited the ED from March to August 2013 were included in this study. Cardiac marker testing was performed using the Triage Cardio3 panel (Alere, USA). Electronic medical records were collected on August 2014. RESULTS: We found that 22.2% patients had elevated BNP and/or cTnI (12.8% with only elevated BNP, 4.4% with only elevated cTnI, and 5.0% with both elevations). Patients with elevations in both marker levels showed significantly higher admission rate (78.5% vs. 62.7%, P=0.006) and longer length of hospital stay (11 vs. 6 days, P=0.001) than those with only elevated cTnI. Patients with elevations in both marker levels also showed higher admission rate (78.5% vs. 67.3%, P=0.016) and higher BNP levels (430 vs. 194 pg/mL, P<0.001) than those with only elevated BNP. CONCLUSIONS: Concurrent elevation of BNP and cTnI may be associated with inferior clinical outcome and combined testing of cTnI and BNP levels with high sensitivity would provide important information for assisting management decisions at the ED.
Acute Coronary Syndrome ; Electronic Health Records ; Emergencies* ; Emergency Service, Hospital* ; Heart Failure ; Humans ; Length of Stay ; Natriuretic Peptide, Brain ; Point-of-Care Systems* ; Triage ; Troponin ; Troponin I

BACKGROUND: For correct interpretation of the high-density lipoprotein cholesterol (HDL-C) data from the Korea National Health and Nutrition Examination Survey (KNHANES), the values should be comparable to reference values. We aimed to suggest a way to calibrate KNHANES HDL-C data from 2008 to 2015 to the Centers for Disease Control and Prevention (CDC) reference method values. METHODS: We derived three calibration equations based on comparisons between the HDL-C values of the KNHANES laboratory and the CDC reference method values in 2009, 2012, and 2015 using commutable frozen serum samples. The selection of calibration equation for correcting KNHANES HDL-C in each year was determined by the accuracy-based external quality assurance results of the KNHANES laboratory. RESULTS: Significant positive biases of HDL-C values were observed in all years (2.85-9.40%). We created the following calibration equations: standard HDL-C=0.872×[original KNHANES HDL-C]+2.460 for 2008, 2009, and 2010; standard HDL-C=0.952×[original KNHANES HDL-C]+1.096 for 2012, 2013, and 2014; and standard HDL-C=1.01×[original KNHANES HDL-C]-3.172 for 2011 and 2015. We calibrated the biases of KNHANES HDL-C data using the calibration equations. CONCLUSIONS: Since the KNHANES HDL-C values (2008-2015) showed substantial positive biases compared with the CDC reference method values, we suggested using calibration equations to correct KNHANES data from these years. Since the necessity for correcting the biases depends on the characteristics of research topics, each researcher should determine whether to calibrate KNHANES HDL-C data or not for each study.
Algorithms ; Calibration ; Cholesterol, HDL/*blood/standards ; Humans ; *Nutrition Surveys ; Reference Values ; Republic of Korea