Variations in the disappearance rate of indocyanine green.
Time-associated changes in the disappearance rate of indocyanine green from the blood (K.ICG) as an index of liver function, were studied. Blood was drawn 5 times at 3-minute intervals from 32 patients. Early, intermediate, and late K.ICG values were 0.087 +/- 0.040, 0.082 +/- 0.038, and 0.076 +/- 0.033 min-1, respectively, showing serial decreases. When blood was drawn 8 times at 2-minute intervals from 22 other patients, the means of the K.ICG values at 11 time points showed a nearly linear relationship (r = -0.986). These findings indicated that K.ICG is approximated by a linear function of time, K(t) = -K'.t + K0. According to this function, K.ICG is considered to decrease by 1.96% every minute. The K.ICG value determined by the conventional method is, therefore, a mean disappearance rate of 15 minutes, and K0 is considered to reflect the initial reaction speed.
Kumazawa
K
K
Department of Surgery, Tokyo Women's Medical College, Daini Hospital, Japan.
Kikuchi
T
T
Oishi
T
T
Nakajima
H
H
Ohigashi
S
S
Kato
H
H
Kajiwara
T
T
Sakakibara
N
N
D002779:Cholestasis / Q000175:diagnosis; D006801:Humans; D007208:Indocyanine Green / Q000097:blood / Q000493:pharmacokinetics*; D008103:Liver Cirrhosis / Q000175:diagnosis; D008111:Liver Function Tests; D008113:Liver Neoplasms / Q000175:diagnosis; D012044:Regression Analysis; D013997:Time Factors
D007208:Indocyanine Green