Performance of the epoc Blood Analysis System
Objectives: To describe validation and performance of epoc, a blood gas analysis point-of-care system, in a live clinical setting.
Methods: Data were collected for 156 epoc systems over 12 months. Preimplementation precision and correlation studies and postimplementation quality assurance data were collected, including test card, reader, and personal data assistant (PDA) failure rates.
Results: The coefficient of variation was clinically acceptable for all analytes. Correlation studies yielded an R from 0.901 (for sodium) to 0.994 (for potassium) with the Nova analyzer and from 0.961 (sodium) to 0.991 (glucose) with the i-STAT. Average test card failure rate was 13%. Of the PDA/reader units, 55% needed repair within 1 year.
Conclusions: The analytical performance showed high precision and good correlation with the Nova and i-STAT platforms. Test card and instrument failure rates were higher than that of the i-STAT system.
Blood gas analysis can be performed in a laboratory or at the point of care (POC). The advantages of central laboratory testing include higher accuracy and precision associated with the use of a few large, well-maintained instruments operated by highly trained laboratory professionals, as well as lower costs due to the cheaper reagents and more efficient use of labor. Transport delays, sample queuing, and the need to look up the results in the electronic medical record have led many hospitals to use POC devices for urgent samples. Although POC instruments provide much faster turnaround times than a central laboratory, the reliability of results can be compromised because of testing by clinical staff, whose primary expertise is not laboratory work. In addition, the cost per test is usually higher for POC assays due to higher reagent/cartridge costs.
Historically, i-STAT instruments (Abbott Point of Care, Princeton, NJ) dominated the POC blood gas and electrolyte testing market in the United States. The US Food and Drug Administration approved the epoc blood gas and electrolyte analysis system (Alere, Waltham, MA) in 2006 for testing many of the analytes available on the i-STAT platform. The epoc instruments, which use similar technology to the i-STAT, are being marketed as a cost-effective alternative. In addition to cost, the advantages of epoc include built-in Wi-Fi connectivity and individually barcoded cards that can be stored at room temperature. The analytical performance of the epoc blood analysis system was found to be comparable to the i-STAT for pH, CO2, O2, sodium, potassium, ionized calcium, and hematocrit. Our institution was among the first large academic medical centers to implement the epoc. This communication describes the performance of the epoc system in a large clinical setting and its effects on the total use of blood gas analysis. We also extend the prior analytical evaluation to include glucose and lactate, two analytes that were not previously available on the epoc, and correlate the epoc results with central laboratory methods.
Abstract and Introduction
Abstract
Objectives: To describe validation and performance of epoc, a blood gas analysis point-of-care system, in a live clinical setting.
Methods: Data were collected for 156 epoc systems over 12 months. Preimplementation precision and correlation studies and postimplementation quality assurance data were collected, including test card, reader, and personal data assistant (PDA) failure rates.
Results: The coefficient of variation was clinically acceptable for all analytes. Correlation studies yielded an R from 0.901 (for sodium) to 0.994 (for potassium) with the Nova analyzer and from 0.961 (sodium) to 0.991 (glucose) with the i-STAT. Average test card failure rate was 13%. Of the PDA/reader units, 55% needed repair within 1 year.
Conclusions: The analytical performance showed high precision and good correlation with the Nova and i-STAT platforms. Test card and instrument failure rates were higher than that of the i-STAT system.
Introduction
Blood gas analysis can be performed in a laboratory or at the point of care (POC). The advantages of central laboratory testing include higher accuracy and precision associated with the use of a few large, well-maintained instruments operated by highly trained laboratory professionals, as well as lower costs due to the cheaper reagents and more efficient use of labor. Transport delays, sample queuing, and the need to look up the results in the electronic medical record have led many hospitals to use POC devices for urgent samples. Although POC instruments provide much faster turnaround times than a central laboratory, the reliability of results can be compromised because of testing by clinical staff, whose primary expertise is not laboratory work. In addition, the cost per test is usually higher for POC assays due to higher reagent/cartridge costs.
Historically, i-STAT instruments (Abbott Point of Care, Princeton, NJ) dominated the POC blood gas and electrolyte testing market in the United States. The US Food and Drug Administration approved the epoc blood gas and electrolyte analysis system (Alere, Waltham, MA) in 2006 for testing many of the analytes available on the i-STAT platform. The epoc instruments, which use similar technology to the i-STAT, are being marketed as a cost-effective alternative. In addition to cost, the advantages of epoc include built-in Wi-Fi connectivity and individually barcoded cards that can be stored at room temperature. The analytical performance of the epoc blood analysis system was found to be comparable to the i-STAT for pH, CO2, O2, sodium, potassium, ionized calcium, and hematocrit. Our institution was among the first large academic medical centers to implement the epoc. This communication describes the performance of the epoc system in a large clinical setting and its effects on the total use of blood gas analysis. We also extend the prior analytical evaluation to include glucose and lactate, two analytes that were not previously available on the epoc, and correlate the epoc results with central laboratory methods.