Mather L E, Owen H
Department of Anaesthesia and Intensive Care, Flinders Medical Centre, Flinders University of South Australia, Adelaide.
Anaesth Intensive Care. 1988 Nov;16(4):427-36. doi: 10.1177/0310057X8801600408.
The current practice of patient-controlled analgesia has grown from empirical observations. Although several variants of patient-controlled analgesia, bolus doses, infusions, or combinations of both, have been suggested, a scientific basis for advocating one variant over the others has been lacking. Most systems have been based on the simplest system, bolus demand, although the use of a combined bolus and background infusion method has theoretical merit. Similarly, a scientific basis for setting the variables of patient-controlled analgesia, drug choice, incremental dose, maximum dose and lockout interval, also has been lacking. Settings for these variables may be rationalised post hoc on the basis of the physicochemical properties and global pharmacokinetic properties of the opioids used but knowledge of these properties has not helped in setting the variables a priori. Foremost, the drug choice should be based on therapeutic index. Knowledge of the regional kinetics of drug (influx and efflux) from brain may provide a more logical basis for setting the patient-controlled analgesia variables but such information can only come from animal experiments. More research is required if patient-controlled analgesia is to become anything but an empirical tool in the quest for improved analgesia in patients.
目前患者自控镇痛的实践源于经验观察。尽管有人提出了患者自控镇痛的几种变体，如单次剂量、输注或两者结合，但一直缺乏支持一种变体优于其他变体的科学依据。大多数系统基于最简单的系统，即单次剂量需求，尽管联合单次剂量和背景输注方法具有理论优势。同样，也缺乏设定患者自控镇痛变量（药物选择、增量剂量、最大剂量和锁定间隔）的科学依据。这些变量的设置可能会根据所用阿片类药物的物理化学性质和整体药代动力学性质事后合理化，但这些性质的知识无助于事先设定变量。首先，药物选择应基于治疗指数。了解药物从脑内的区域动力学（流入和流出）可能为设定患者自控镇痛变量提供更合理的依据，但此类信息只能来自动物实验。如果患者自控镇痛想要在寻求改善患者镇痛效果方面不仅仅成为一种经验性工具，就需要更多的研究。
