Digoxin clearance and serum beta-2-microglobulin in neonates.
To find reliable indicators of digoxin clearance (CLdig) in the neonatal period, we investigated the linear correlation of CLdig and the reciprocal of CLdig (1/CLdig) with serum beta 2-microglobulin (S beta 2-MG), serum creatinine, blood urea nitrogen, age, and weight on 25 occasions in 21 neonates with congenital heart disease. The S beta 2-MG value showed a significantly closer correlation to 1/CLdig (r = 0.84, p less than 0.0001) than to the other values. The regression equation was (1/CLdig) = 0.15 X (s beta 2-MG) + 0.08. Creatinine and blood urea nitrogen values correlated less closely with 1/CLdig (r = 0.67 and 0.71, respectively). Age and weight had no significant linear correlation with CLdig and 1/CLdig. Determination of s beta 2-MG values allowed an estimate of CLdig by means of the regression equation between s beta 2-MG and 1/CLdig, and permitted a prediction of the required maintenance dose of digoxin. We conclude that s beta 2-MG is a good indicator of CLdig in neonates, and that the determination of s beta 2-MG values may facilitate the advance individualization of digoxin therapy in the neonatal period.
Ito
S
S
Department of Pediatrics, Asahikawa Medical College, Japan.
Oka
R
R
Tsuchida
A
A
Yoshioka
H
H
Mori
Y
Y
D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000097:blood; D004077:Digoxin / Q000493:pharmacokinetics*; D005260:Female; D006330:Heart Defects, Congenital / Q000188:drug therapy*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011446:Prospective Studies; D012189:Retrospective Studies; D001613:beta 2-Microglobulin / Q000032:analysis*
D001613:beta 2-Microglobulin; D004077:Digoxin; D003404:Creatinine