Performance Evaluation of the Stat Profile pHOx Ultra Blood Gas Analyzer

The objective of this study was to evaluate the analytical performance of the Stat Profile pHOx Ultra Blood Gas Analyzer (Nova Biomedical, USA), a new blood gas/chemistry analyser, including its precision and linearity, comparison studies, and the carry-over effect of commercial reagents and patient specimens. We assessed all the results on the basis of the Clinical and Laboratory Standards Institute guidelines. The following parameters were assessed: pH, partial pressure of carbon dioxide, partial pressure of oxygen, ionized calcium, ionized magnesium (iMg), and lactate concentration The total imprecision had a coefficient of variation of 0.0%–1.8%, and the linear measurement ranges for each parameter were all acceptable. In comparison with the Nova Critical Care Xpress Analyzer (Nova Biomedical, USA), the results indicated a good agreement, except for iMg. All carry-over ranges were between −0.5% and −1.4%. The Stat Profile pHOx Ultra Blood Gas Analyzer showed good analytical performance in terms of precision, linearity, comparison studies, and carry-over effect. The Stat Profile pHOx Ultra Blood Gas Analyzer can provide reliable measurements across a clinically relevant range and has potential use in laboratory tests.

Performance Evaluation of Cartridge-Type Blood Gas Analyzer: i-Smart 300

BACKGROUND: Blood gas analysis plays a crucial role in critical care settings, and immediate and precise analysis improves clinical outcomes through prompt treatment. We evaluated the performance of a cartridge-type blood gas analyzer, i-Smart 300 (i-SENS, Korea), according to the Clinical and Laboratory Standard Institute (CLSI) guidelines and compared it to a conventional blood gas analyzer. METHODS: The precision was evaluated according to CLSI EP5-A3. The i-Smart 300 was compared to the Stat Profile Critical Care Xpress (STP CCX) (Nova CCX; Nova Biomedical, USA) according to CLSI EP9-A3 using the following eight parameters: pH, partial carbon dioxide pressure, partial oxygen pressure, sodium, potassium, chloride, ionized calcium, and hematocrit. Linearity was determined using five levels of control materials according to CLSI EP6-A. RESULTS: Within-run precision and total precision, demonstrated as coefficients of variation, ranged from 0.02 to 2.50% and from 0.05 to 3.46%, respectively. Correlation analysis yielded a correlation coefficient from 0.966 to 0.996 between the i-Smart 300 and the conventional analyzer (Nova CCX). The i-Smart 300 showed excellent linearity at eight parameters with acceptable percent recovery. CONCLUSIONS: The i-Smart 300, a portable cartridge-type blood gas analyzer, showed high precision and good correlation with a traditional bench-top blood gas analyzer. It could be useful in critical care settings.

Comparisons of electrolytes were measured by Point-of-care testing and auto-analyzer / Эрүүл мэндийн лаборатори

Introduction@#Electrolyte values are measured by two different analyzers: arterial blood gas (Point of care) and auto-analyzers. Those two has different methods to measure electrolytes and have several pros and cons. We evaluated if there was agreement between whole blood electrolytes measured by a point-of-care device and serum electrolytes measured using indirect ion-selective electrodes. @*Materials and methods@#An observational cohort study was conducted in 50 paired venous samples from patients admitted in Gurvan gal central hospital. Those were analyzed on OPTC blood gas devise and Roche c-501 auto-analyzer. Statistical analyses were performed using paired t-test and persons’ correlation test. @*Results@#Sodium mean range was 138.54 mmol/l (SD=3.69) by blood gas analyser, but by the automated analyser mean range was 140.75 mmol/l (SD=4.45). Mean difference of the normal sodium group was 1.77 (SD=1.65, p=0.039), and hyposodium group was 4.4 (SD=0.33, p=0.007). Pottasium mean range was 3.13 mmol/l (SD=0.53) by blood gas analyser, but by the automated analyser mean range was 4.42 mmol/l (SD=0.45). Mean difference of the normal sodium group was 0.18 (p<0.001), and hypokalemi group was 1.44 (p<0.001). @*Conclusion@#Clinicians should be aware of the difference between whole blood and serum electrolytes. A correction factor needs to be determined at each laboratory.

Utilization of IQM data of GEM3000 blood gas analyzer for evaluating instrument performance / 国际检验医学杂志

Objective To apply the IQM quality data of the GEM 3000 blood gas analyzer to evaluate the instrument performance and to compared it with the traditional evaluation method .Methods The precision and accuracy were calculated by using the IQM data ,the external quality control substance was adopted to verify the main performance indexes of the blood gas analyzer .Results The precision of PH ,PCO2 and PO2 calculated by using the IQM data was 0 .02% ,2 .16% and 0 .63% ,which by the traditional e-valuation method was 0 .07% ,1 .68% and 1 .28% respectively ,the accuracy of PH ,PCO2 and PO2 calculated by using the IQM data was 0 .00% ,1 .15% and 0 .49% ,which by the traditional evaluation method was 0 .11% ,2 .91% and 1 .07% respectively .Conclu-sion The intelligent quality management can provide objective and reliable indicators for the performance evaluation of the blood gas analyzer ,and compared with the traditional performance evaluation scheme which is more simple and convenient to operate .

Comparison of the determination results of potassium by blood-gas analyzer and dry chemical analyzer / 国际检验医学杂志

Objective To analyze the comparability of potassium results detected by blood-gas analyzer and dry chemical analy-zer .Methods Dry chemical detection system was used as comparison method (X) ,and blood gas analyzer systems was used as the experimental method (Y ) .Arterial blood samples collected from ICU newborns were detected respectively by the two methods .If SE of medical decision level was less than or equal to 1/2 TEa decided by CLIA′88 ,the results was acceptable .Results There was a linear correlation in potassium concentrations of the two detection systems(r=0 .976 ,P<0 .01) .But among three medical decision levels ,the SE of the two detection systems only acceptable at 3 .0 mmol/L .Conclusion The potassium concentration of blood gas analyzer is lower than that of dry chemistry analyzer .The potassium concentration of dry chemistry analyzer should be taken as a reference to diagnose and clinical treatment .

Use of Point-of-Care Blood gas Analyzer for Potassium Measurement in Cardiac Arrest Cases

PURPOSE: The aim of this study was to assess agreement of potassium test results between the point-of-care-testing (POCT) blood gas analyzer and central laboratory (CL) biochemistry analysis associated with cardiopulmonary resuscitation (CPR) cases. METHODS: This was a prospective, comparative study of 108- paired results conducted between January 2009 and December 2010. Blood specimens were collected within 5 minutes of arrival to the emergency department from the femoral artery of cardiac arrest patients, and specimens were used for both arterial blood gas and routine laboratory analysis. Arterial blood gas analysis samples were immediately analyzed using a POCT blood gas machine [GEM Premier 3000 analyzer (Instrumentation Laboratory, Lexington, MA)]. Potassium levels obtained from the POCT arterial blood gas analyzer and subsequent CL biochemistry analysis were then compared. RESULTS: Mean values of potassium measured were 5.17+/-1.72 mmol/l using POCT and 5.37+/-1.79 mmol/l using CL. The mean difference+/-SD between simultaneous POCT and CL measurements was 0.19+/-0.66 mmol/l, with 95% limits of agreement of -1.48 to 1.10 mmol/l. The sensitivity, specificity, positive predictive value, and negative predictive value of POCT in diagnosing life threatening hyperkalaemia (> 6.5 mmol/l) were 85%, 97%, 85%, and 97%, respectively. CONCLUSION: The mean difference between the results obtained from the POCT blood gas analyzer and CL analysis were small. POCT is a thus a useful method for rapidly detecting life-threatening hyperkalaemia during CPR. However, due to wide limits of agreements, caution in interpretation of POCT results is necessary.

Experience on rescue of patients with severe multiple injuries after sudden disaster under field condition / 第二军医大学学报

Objective: To study the rescue strategy for patients with severe multiple injuries after sudden disaster under field condition. Methods and results: A 53-year-old female patient was referred to us after hit on the pelvis in the China Wenchuan earthquake. Her symptoms included large volume of hematuria, difficult breath, tenderness of the whole abdomen, and bedsore. Portable B ultrasound revealed effusion of abdomen and left chest cavity, and bladder rupture. Portable blood-gas analyzer indicated severe anemia + hypoxemia + hypokalemia + acidosis. Drainage was done through left chest cavity aspiration and bladder aspiration. Abdominal examination found rectal rupture (perforation), which was managed by Harttman + cystostomy followed by anti-infection treatment. The patient recovered 18 days after operation. Conclusion: The rich experience and skillful surgical management, the full play of portable equipment, the help from the local hospital, together with timely anti-infection management, are the keys to successful rescue of patients with severe multiple injuries under field condition.

Assessment of Blood Glucose Values Measured by Blood Gas Analyzer or Portable Glucometer / 대한마취과학회지

BACKGROUND: A portable glucometer is commonly used to immediately check the blood glucose level. In the anesthetic field, some blood gas analyzers can also give a rapid indication of the blood sugar level but the accuracy is unknown. Therefore, this study assessed the accuracy of the blood glucose values measured by either a blood gas analyzer or portable glucometer. METHODS: Venous blood from diabetic patients was used to measure the glucose level with either a blood gas analyzer or a portable glucometer. The difference and 5% deviation from reference values was analyzed. These values were also assessed using a Bland-Altman plot and clinical significance was examined using a Clarke error grid. RESULTS: The differences from the reference values were smaller using the blood gas analyzer (1.3 +/- 7.8 mg/dl) than using the portable glucometer (-5.1 +/- 16.7 mg/dl)(P < 0.01). 73.4% of the values measured by the blood gas analyzer and 40.0% of those measured by the portable glucometer were within 5% of the reference value. The 95% limits of agreement in the difference ranged from -14.3 to 16.9 in the blood gas analyzer and -38.5 to 28.2 in the portable glucometer. Error grid analysis showed that 100% of the values measured by the blood gas analyzer were located in zone A. When locating the values measured using the portable glucometer, 95.6% were located in zone A, and the remaining 4.4% are located in zone B. CONCLUSIONS: The blood gas analyzer measures the blood glucose more accurately than the portable glucometer. However, the blood glucose values measured by the portable glucometer are clinically acceptable.

Installation of Data Management System for Point-of-care Blood Gas Analyzers using Local Area Network / 대한진단검사의학회지

BACKGROUND: Point-of-care (POC) testing is expanding because of the many advantages, such as faster turnaround time, immediate decision making and patient management. However, POC testing has problems; poor maintenance and quality control of devices and management of test results. We installed data management system (DMS) for POC blood gas analyzers using local area network for the resolution of those problems. METHODS: We connected nine POC blood gas analyzers Rapidpoint 400 (Bayer Diagnostics Ltd., Newbury, UK) to POC data manager Rapidlink (Bayer Diagnostics Ltd.) by device interface using local area network and developed in-house program for connecting POC data manager to laboratory information system (LIS)/hospital information system (HIS). We surveyed user acceptability and reliability of test results. We examined patterns of problems detected and solved in operating DMS based on quality records. We calculated the change of the yearly test numbers of arterial blood gas analysis (ABGA) after installation of DMS. RESULTS: Test results of POC blood gas analyzers were transferred to LIS and could be checked in HIS. By means of user survey, we judged that the users of POC blood gas analyzers operated the devices with ease and thought test results reliable. POC data manager server implemented in central laboratory enabled remote maintenance and quality control of devices with little workload. POC ABGA test number increased by 3.7 fold during the two years. CONCLUSIONS: We developed DMS for POC blood gas analyzers, enabling test result retrieval and remote maintenance and quality control of devices. This is very informative study for other hospitals installing DMS for POC testing in Korea.

Relationship between Arterial and End-tidal Carbon Dioxide Tension during General Anesthesia for Caesarean Section / 대한마취과학회지

Studies were made to ascertain the relationship between arterial and end-tidal carbon dioxide tension in 19 patients during caesarean section under general anesthesia(Group 2). 27 nonpregnant patients scheduled for abdominal hysterectomy were also performed as a control group(Group I). 15 and 30 minutes after the induction of anesthesia in group I, and just before uterine incision, 15 minutes following induction in group 2, arterial blood was sampled for PaCO analysis and PETCO2(end-tidal CO2 tension) determined at the same time. In group 1, there was a statistically significant differences between PaCO2 and PETCO2 but in group 2, no differences between them were shown. The highly significant correlations between PaCO2 and PETCO2 in both groups were found. On the basis of the above results, we recommend that non-invasive measurement of PETCO2 can be used reliably in stead of measuring PaO2 to evaluate the ventilatory status during anesthesia in patients for caesarean section.

Relationship between Arterial and End-tidal Carbon Dioxide Tension during General Anesthesia for Caesarean Section / 대한마취과학회지

Studies were made to ascertain the relationship between arterial and end-tidal carbon dioxide tension in 19 patients during caesarean section under general anesthesia(Group 2). 27 nonpregnant patients scheduled for abdominal hysterectomy were also performed as a control group(Group I). 15 and 30 minutes after the induction of anesthesia in group I, and just before uterine incision, 15 minutes following induction in group 2, arterial blood was sampled for PaCO analysis and PETCO2(end-tidal CO2 tension) determined at the same time. In group 1, there was a statistically significant differences between PaCO2 and PETCO2 but in group 2, no differences between them were shown. The highly significant correlations between PaCO2 and PETCO2 in both groups were found. On the basis of the above results, we recommend that non-invasive measurement of PETCO2 can be used reliably in stead of measuring PaO2 to evaluate the ventilatory status during anesthesia in patients for caesarean section.