Padbury J F, Agata Y, Baylen B G, Ludlow J K, Polk D H, Habib D M, Martinez A M
Department of Pediatrics, Harbor-UCLA Medical Center, University of California, Los Angeles School of Medicine, Torrance 90509.
J Pediatr. 1990 Sep;117(3):472-6. doi: 10.1016/s0022-3476(05)81101-1.
Dopamine pharmacokinetics was investigated in 14 critically ill newborn infants ranging from 27 to 43 weeks of gestational age and from 0.9 to greater than 4 kg birth weight. Plasma clearance rate was determined from dopamine levels during controlled infusions under actual clinical conditions. Dopamine was administered in stepwise increasing doses up to 8 micrograms/kg/min. Dopamine concentration and dopamine clearance rate were determined from duplicate samples drawn during each infusion in each patient. Steady-state plasma dopamine concentrations and plasma clearance rates were observed within 20 minutes at each infusion. Plasma dopamine concentration ranged from 0.5 ng/ml before infusion to almost 70 ng/ml at an infusion rate of 4 to 8 micrograms/kg/min. There was a linear correlation between infusion rate and plasma dopamine concentration (r = 0.68, p less than 0.001). Neither plasma dopamine concentration nor infusion rate had a significant effect on clearance rate. These data are consistent with first-order kinetics for administered dopamine in critically ill neonates over the range of concentrations studied.
对14名孕周为27至43周、出生体重为0.9至4千克以上的危重新生儿进行了多巴胺药代动力学研究。在实际临床条件下，通过控制输注期间的多巴胺水平来测定血浆清除率。多巴胺以逐步递增的剂量给药，最高可达8微克/千克/分钟。从每位患者每次输注期间采集的两份重复样本中测定多巴胺浓度和多巴胺清除率。在每次输注的20分钟内观察到稳态血浆多巴胺浓度和血浆清除率。血浆多巴胺浓度在输注前为0.5纳克/毫升，在输注速率为4至8微克/千克/分钟时几乎达到70纳克/毫升。输注速率与血浆多巴胺浓度之间存在线性相关性（r = 0.68，p < 0.001）。血浆多巴胺浓度和输注速率对清除率均无显著影响。这些数据与在研究浓度范围内危重新生儿中给予多巴胺的一级动力学一致。
