Oda Y, Kariya N, Nakamoto T, Nishi S, Asada A, Fujimori M
Department of Anesthesiology and Intensive Care Medicine, Osaka City University Medical School, Japan.
Ther Drug Monit. 1995 Apr;17(2):207-10. doi: 10.1097/00007691-199504000-00019.
Lidocaine was used for evaluation of hepatic function in a patient undergoing hepatic resection. Preoperatively, half-life of indocyanine green (ICG) was 33 min after intravenous administration. Plasma concentration of the N-dealkylated metabolite of lidocaine, monoethylglycinexylidide (MEGX), was quantitatively determined to evaluate hepatic function. The patient's rate of formation of MEGX at 15 min after administration of lidocaine was within normal limits, at 56 micrograms/L. These findings suggest that in this patient, hepatic cytochrome P-450IIIA activity was not impaired, but selective impairment of uptake of ICG into hepatocytes or excretion into the bile ducts was present. The rate of formation of MEGX was decreased, and plasma concentration of bilirubin was elevated postsurgically; this could have been the result of decreased cytochrome P-450IIIA activity or decreased hepatic blood flow after hepatic resection. We conclude that the rate of formation of MEGX is a better index of hepatic function than is ICG half-life.
利多卡因被用于评估一位正在接受肝切除术患者的肝功能。术前，静脉注射吲哚菁绿（ICG）后的半衰期为33分钟。定量测定利多卡因的N-脱烷基代谢产物单乙基甘氨酰二甲苯（MEGX）的血浆浓度以评估肝功能。利多卡因给药后15分钟时，该患者的MEGX生成速率在正常范围内，为56微克/升。这些发现表明，在该患者中，肝细胞色素P-450IIIA活性未受损，但存在ICG摄取到肝细胞或排泄到胆管中的选择性受损。MEGX的生成速率降低，术后胆红素血浆浓度升高；这可能是肝切除术后细胞色素P-450IIIA活性降低或肝血流量减少的结果。我们得出结论，MEGX的生成速率比ICG半衰期是更好的肝功能指标。
