Accuracy of Glucometers Should Not Be Assumed

Conclusions in the article by Lacara and colleagues¹ contradict recent work soon to be published by our laboratory on the accuracy of bedside glucometer testing in the critical care setting. Our findings demonstrate that hematocrit has a significant effect on the accuracy of widely used point-of-care (POC) glucometers, and we noted that this effect becomes clinically meaningful when red cell volume is less than 34%. Many centers practice permissive anemia^2,–4 to reduce exposure to transfused blood, and the higher prevalence of low hematocrits has reduced the accuracy of POC glucose analyzers.^5,6 

The authors discuss the nationally accepted standard error of glucometers of ±20%, but these devices are not intended for intensive care use. Such a degree of inaccuracy is a holdover from a time before tight glucose control became common practice, and should not be accepted by centers that target a glucose...