The objective of this study was to describe the performance of POCG measurements under routine clinical conditions when results were in the critical value range as reported by participants in the College of American Pathologists (CAP) Q-Probes program.
Participants were instructed to collect retrospective data on the previous 50 cases in which POCG test results were within their critical range or for all critical results within the past 6 month if fewer than 50 cases were found.
Participants also provided information about relative test volume among inpatient, critical care, and emergency department locations as well as the number of operators trained and certified to perform POCG testing.
Table 2 shows the estimated 2012 volume of POCG testing.
Among 49 participants, 35 (71.4%) reported that retesting another specimen was done for POCG results in their critical value range.
Among the critical POCG tests not confirmed, the median repeat value was 101 mg/dL for critical low values and 418 mg/dL for critical high values.
A total of 105 928 POCG measurements were performed during a 12-month period between April 2012 and March 2013.
During the study period, 577 certified POCG operators performed one or more POCG tests.
Among all 22 critical POCG results of less than 10 mg/dL, only 2 cases (9%) remained in the critical range (<10 and 21 mg/dL) when retested.
Among all 204 specimens retested within 10 minutes of initial POCG critical results, the cumulative percentages retested at 2, 3, and 4 minutes were 110 (53.9%) 154 (75.5%), and 172 (84.3%), respectively.
Among 188 repeat capillary POCG measurements made within 10 minutes of initial critical value, a different glucose meter was used in 51 (27.1%) and a different operator in 82 (43.6%).
Among all POCG critical values, 90.2% (231 of 256) were repeated within 60 minutes including 86.3% of critical high (115 of 133) and all but one of the critical low (70 of 71; 99%) values.