Thank you for the article by Cook et al1 warning that significantly different results can be obtained when measuring blood glucose if the source is a fingerstick versus a central venous catheter. One revelation in the article was that “most POC glucose meters have an adjustment to correct glucose values from capillary blood to more closely approximate laboratory glucose values of venous blood.”1 Differences in these results have been the subject of scholarly debate for some time, but we must inject an element of realism: as long as there are critically ill patients without arterial lines, there are likely to be nurses who either are unaware of these differences, recognize the pain a fingerstick causes, or try to save time by using a point-of-care (POC) meter on blood they have already drawn for other purposes from a central venous line.
As this practice at the POC is unlikely...