Upton R N, Huang Y F
Department of Anaesthesia and Intensive Care, Royal Adelaide Hospital, University of Adelaide, SA, Australia.
Br J Anaesth. 1993 Mar;70(3):333-8. doi: 10.1093/bja/70.3.333.
The aim of this study was to quantitate factors affecting the initial "peak" of the pulmonary artery (PA) drug concentrations after i.v. bolus drug administration, which is a determinant of the subsequent drug uptake into both the lungs and other well-perfused organs. Indocyanine green (ICG) was used as a marker drug in anaesthetized (1.5% halothane) sheep prepared with an inferior vena cava injection catheter and a large-gauge pulmonary artery blood sampling catheter. For three ranges of cardiac output, 2.5-mg doses of ICG were injected in the following combinations: 10 ml injected over 1, 5 or 10 s; 5 or 25 ml injected over 1 s. On-line PA ICG concentrations were recorded for approximately 60 s using a densitometer. The mean maximum PA ICG concentrations (2-8 mg litre-1), the mean times at which they occurred (7-18 s after injection) and the time lags before ICG was detected in the PA (4-9 s), were inversely related to cardiac output, but linearly related to the time over which the injection was made. The area under the curve of the peak was related inversely to cardiac output only, while the aspect ratio of the peak was related inversely to the time over which the injection was made only. The injectate volume had no effect on any of the measured values. We conclude that, in some circumstances, the rate of injection of drugs with narrow margins of safety should be tailored to the cardiac output of an individual.
本研究的目的是对静脉推注给药后影响肺动脉（PA）药物浓度初始“峰值”的因素进行定量分析，该峰值是随后药物进入肺和其他灌注良好器官的决定因素。吲哚菁绿（ICG）被用作标记药物，对用下腔静脉注射导管和大口径肺动脉采血导管制备的麻醉（1.5%氟烷）绵羊进行研究。对于三个心输出量范围，以以下组合注射2.5mg剂量的ICG：10ml在1、5或10秒内注射；5或25ml在1秒内注射。使用密度计记录约60秒的在线PA ICG浓度。平均最大PA ICG浓度（2 - 8mg/升）、其出现的平均时间（注射后7 - 18秒）以及在PA中检测到ICG之前的时间滞后（4 - 9秒）与心输出量呈负相关，但与注射时间呈线性相关。峰值曲线下面积仅与心输出量呈负相关，而峰值的纵横比仅与注射时间呈负相关。注射体积对任何测量值均无影响。我们得出结论，在某些情况下，安全范围窄的药物的注射速率应根据个体的心输出量进行调整。
