Clinical utility of a bedside blood analyzer for measuring blood chemistry values in neonates

The purpose of this study was to determine whether blood chemistry measurements obtained by a bedside blood analyzer through an umbilical artery catheter agreed with those obtained with use of conventional laboratory analyzers.

Forty-two neonates (1910 +/- 1000 gm) being treated in a level III neonatal intensive care unit had 88 blood samples drawn through an umbilical artery catheter. Serum sodium, potassium, glucose, and hematocrit concentrations were measured (n = 352) with use of a laboratory analyzer (0.7 ml of blood) and a bedside blood analyzer (0.06 ml of blood).

Only 5.7% of all measurement differences (20/352) were outside the predetermined clinically acceptable difference range, and just 1.4% (5/352) might have affected clinical decision making. Correlations between laboratory analyzer measurements and bedside blood analyzer measurements were excellent: serum potassium, r = 0.97, p = 0.0001; serum glucose, r = 0.93, p = 0.0001; and blood hematocrit, r = 0.93, p = 0.0001. Serum sodium measurement correlation was significant (p = 0.0001) but weaker (r = 0.86).

The bedside blood analyzer evaluated in this report is clinically useful for neonatal patients and could limit phlebotomy loss if used routinely.