Capillary (Heelstick) versus Venous Blood Sampling for the Determination of Glucose Concentration in the Neonate

Abstract

Various sites may be used to obtain blood (plasma) for the determination of the glucose concentration in the neonate. Because multiple sites may be sampled in the same neonate, it is important to determine the variability in blood glucose concentration which may result from such sampling. Since pain and mechanical forces may be different because of the method used to obtain the capillary (heelstick) blood compared to the venous specimen, the two sites were sampled, and the blood glucose concentration was determined simultaneously in 25 asymptomatic well neonates whose mean birth weight was 2,562 ± 152 g and whose gestational age was 35.5 ± 1.5 weeks. There was a significant (p < 0.0001), but relatively weak correlation (r² = 0.64) between capillary (heelstick) blood and venous blood relative to blood glucose concentration. When the capillary (heelstick)-venous glucose concentration difference was compared to the mean of the capillary (heelstick) and venous glucose concentrations, a difference of ± 0.5 mM (9 mg/dl) was noted in 3 of 25 neonates. Appropriately obtained capillary (heelstick) blood samples provide measurement of blood glucose concentration which are variable compared to venous samples, but which are probably not significant physiologically.

Hypoglycemia in the newborn

“…It is important to also consider the variations between capillary and venous, blood and plasma, and immediate and stored samples (whole blood sugar is 10-15% less than the plasma sugar, the glucose levels can fall by 14-18 mg/dL per hour in blood samples that await the analysis. 9 ) b. Laboratory diagnosis: This is the most accurate method.…”

Hypoglycemia in the Newborn

“…However, treatment may be initiated based on the results of the reagent strips. It is important to also consider the variations between capillary and venous, blood and plasma, and immediate and stored samples (whole blood sugar is 10-15% less than the plasma sugar, the glucose levels can fall by 14-18 mg/dL per hr in blood samples that await the analysis [13].) Arterial samples have slightly higher value compared to venous and capillary samples.…”

Management of Hypoglycemia in Neonatal Period

“…Glukoz seviyelerinin düşmekte ya da yükselmekte olduğunu göstermesi, kan alma zamanlarını belirlemekte yararlı olabilir. Hem hipoglisemi, hem de hiperglisemiye duyarlı olan prematürelerde kullanımı önerilebilir, ancak standart klinik kullanımın bir parçası olmadan önce daha kapsamlı değerlendirilmeleri gerekir (35).…”