Screening for hypoglycemia at the bedside in the neonatal intensive care unit (NICU) with the Abbott PCx glucose meter

Abstract

BackgroundPoint of care (POC) glucose meters are routinely used as a screening tool for hypoglycemia in a neonatal setting. Glucose meters however, lack the same accuracy as laboratory instruments for glucose measurement. In this study we investigated potential reasons for this inaccuracy and established a cut off value for confirmatory testing.MethodsIn this prospective study, all patients in the neonatal intensive care unit who had a plasma glucose test ordered were eligible to participate. Demographic information, sample collection information (nine variables) and a recent hematocrit value were recorded for each sample. Glucose measurements were taken at the bedside on the glucose meter (RN PCx) as well as in the laboratory on both the glucose meter (LAB PCx) and the laboratory analyzer (PG). Data were analyzed by simple and mixed-effects regression analysis and by analysis of a receiver operator characteristics (ROC) curve.ResultsThere were 475 samples analyzed from 132 patients. RN PCx values were higher than PG values (mean = 4.9%), while LAB PCx results were lower (mean = -5.2%) than PG values. Only 31% of the difference between RN PCx – PG and 46% of the difference for LAB PCx – PG could be accounted for by the variables tested. The largest proportion of variance between PCx and PG measurements was explained by hematocrit (about 30%) with a greater effect seen at glucose concentrations ≤4.0 mmol/L (≤72 mg/dL)(48% and 40% for RN PCx and LAB PCx, respectively). The ROC analysis showed that for detection of all cases of hypoglycemia (PG < 2.6 mmol/L)(PG < 47 mg/dL) the PCx screening cut off value would need to be set at 3.8 mmol/L (68 mg/dL) requiring 20% of all samples to have confirmatory analysis by the laboratory method.ConclusionThe large difference between glucose results obtained by PCx glucose meter compared to the laboratory analyzer can be explained in part by hematocrit and low glucose concentration. These results emphasize that the glucose meter is useful only as a screening device for neonatal hypoglycemia and that a screening cut off value must be established.

Glutest Neo Super—a New Handheld Blood Glucose Meter—Corrects for the Effects of the Hematocrit Values in Both Hematocrit-Adjusted Samples and Samples Obtained from Anemic Patients

“…A similar tendency has been described in many previous reports of studies performed using other conventional BG meters. 5,8,9 According to our results, there was a positive bias of approximately 30% in the measurements obtained when the Hct value was 10%. This indicates that a PG level of 2.78 mmol=L (50 mg=dL) corresponds to a WBG level of 3.61 mmol=L (65 mg=dL) when the Hct value is 10%.…”

“…However, as reported previously, many studies performed using conventional BG meters and methods identical to those used in the present study have reported that the Hct values have similar effects on the measurements. 5,[8][9][10] Some of the results obtained for BG meters tested in previous studies are as follows: y ¼ À1.161x þ 0.339, GLUTEST NEO SUPER CORRECTS HEMATOCRIT EFFECT R ¼ À0.693, P < 0.001 for Glutest Neo (Sanwa Kagaku Kenkyusho Co. Ltd.) and y ¼ À1.661x þ 0.516, R ¼ À0.872, P < 0.001 for Precision Ò Xceed Ò (Abbott Diabetes Care, Abbott Park, IL). 5 Similar to the results of our present study, these results also indicated that the WBG levels are overestimated when the Hct value is low and underestimated when the Hct value is high.…”

Leitlinie zur Betreuung von Neugeborenen diabetischer Mütter

“…Da dies nur in einer begrenz ten Anzahl von Einrichtungen gewährleis tet ist, wird meist auf bettseitige Messungen mit "point of care"Geräten ausgewichen. Viele handelsübliche Blutglukosemessstrei fen sind nicht auf neonatale Proben mit ihren potenziell hohen Hämatokrit und niedrigen Glukosewerten ausgerichtet und deshalb bei der Fahndung nach neonatalen Hypoglykämien nur bedingt tauglich [2,3,17,18,31,38,43,52,58,60]. Geräte, die pa rallel zu Glukose den Hämatokrit und die Nichtglukosezucker messen und für die se korrigieren, scheinen akzeptable Werte zu ergeben, publizierte Vergleichsmessun gen im Bereich niedriger Glukosekonzen trationen mit neonatalen Proben sind je doch spärlich [7,64].…”

Challenges to Glycemic Measurement in the Perioperative and Critically Ill Patient: A Review

“…Many POC devices have been shown to be inadequate in this setting. [40][41][42][43] Point-of-care device test strips using glucose oxidase (see later) are prone to errors caused by oxygen effects. Tang and colleagues showed that errors of 15% or more could occur with highly oxygenated blood samples (i.e., PaO 2 >100 mm Hg), 44 and variances of up to 46% from reference values have been observed under hyperbaric conditions.…”