ABSTRACT
Recently, GMCH Laboratory present a point of care analyzer, HemoCue, for Hemoglobin, total WBC and differential counts to reduce turnaround time, especially for pediatric patients. The objective of this study is to validate these tests before introducing it to the patient care. There are 2 units; one for the measurement of Hemoglobin, called Hb201+ and the other for total WBC and differential counts, called HemoCue WBCDIFF. Hb201+ performs photometric measurement of hemoglobin by converting it to hemoglobinazide by special capillary action microcuvettes. In the cuvette for HemoCueWBCDIFF, red blood cells are lysed and white blood cells are stained. Cells are counted and differentiated by image analysis. Whole blood collected in EDTA from patients covering [known value] high to low hemoglobin and total WBC counts was used for precision study. 5 replicates in 5 different runs were used.%CV was calculated and compared against allowable imprecision based on total allowable error TEa for all the parameters. For correlation study, 20 previously analyzed whole blood EDTA samples from patients were analyzed for all the parameters. The values obtained were compared with the results of Sysmex 2000i, automated hematology analyzer. The%bias for the parameters was calculated and compared with allowable%bias based on TEa for each of the parameter and linear regression analysis was performed to calculate coefficient of variance [r].TEa was based on biological variation. Hemoglobin showed a maximum CV of 0.96% and bias of 0.16% and r=0.997. Total WBC count showed maximum CV of 1.27% and the differential WBC count a maximum CV of 3.6% [neutrophils and lymphocytes]. Both, accuracy and precision for the analyzer for all the parameters are acceptable as per the quality goal of TEa and comparable to fully automated hematology analyzer. The POCT is relatively inexpensive, simple to use, battery operated, thus helps to reduce turnaround time and venous sample collection, especially in pediatric patients
ABSTRACT
The objective of the present work was to perform validation study on a group of cardiac biomarkers so that they could be confidently used for the on-spot diagnosis of a range of cardiovascular events like acute coronary syndrome, heart failure and thromboembolic phenomena. A group of cardiac markers including NT-pro BNP, Troponin T, OK- MB, Myoglobin and D-Dimer were recently introduced in GMC Hospital as a point of care using Cobas h232, a handheld device from Roche Company. Precision study was carried out using commercially available control material. Five replicates were carried out across 4 different runs and performed over 5 different days. Coefficient of variation%CV was calculated both for within run and between runs and compared with Total Error Allowable [TEa] for the analytes. The accuracy study for Troponin T was determined by using 8 previously tested heparinized whole blood patient samples obtained from Rashid Laboratory, Dubai, and comparing the result with Cobas h232 available in GMC lab. Percent CV calculated for all analytes was found to be less than TEa. Bias between the achieved target and manufactured target was found to be within one- third of the TEa. The bias achieved, based on the medical decision values was found to be acceptable when compared with TEa. For D-Dimer assay, the bias between the achieved target and manufacture's target was greater than the TEa/3. However it was found within the reference allowable range of the QCcompared with the conversional method the turnaround time was extremely low in the average of 45 minutes. Due to its good analytical agreement with the laboratory methods and ease of use Cobas h232 system for POCT could be reliably used to support on site decision making regarding cardiovascular patients in acute and non-acute settings