Verkaaik A P, Erdmann W
Dept. of Anesthesiology, Erasmus University, Rotterdam, The Netherlands.
Acta Anaesthesiol Belg. 1990;41(3):177-88.
An automatic feed back controlled totally closed circuit system (Physioflex) has been developed for quantitative practice of inhalation anesthesia and ventilation. In the circuit system the gas is moved unidirectionally around by a blower at 70 l/min. In the system four membrane chambers are integrated for ventilation. Besides end-expiratory feed back control of inhalation anesthetics, and inspiratory closed loop control of oxygen, the system offers on-line registration of flow, volume and respiratory pressures as well as a capnogram and oxygen consumption. Alveolar ventilation and static compliance can easily be derived. On-line registration of oxygen consumption has proven to be of value for determination of any impairment of tissue oxygen supply when the oxygen delivery has dropped to critical values. Obstruction of the upper or lower airways are immediately detected and differentiated. Disregulations of metabolism, e.g. in malignant hyperthermia, are seen in a pre-crisis phase (increase of oxygen consumption and of CO2 production), and therapy can be started extremely early and before a disastrous condition has developed. Registration of compliance is only one of the continuously available parameters that guarantee a better and adequate control of lung function (e.g. atalectasis is early detected). The newly developed sophisticated anesthesia device enlarges tremendously the monitoring and respiratory diagnostic possibilities of artificial ventilation, gives new insights in the (patho)physiology and detects disturbances of respiratory parameters and metabolism in an early stage.
已开发出一种自动反馈控制的全封闭回路系统（Physioflex），用于吸入麻醉和通气的定量实践。在该回路系统中，气体由一台鼓风机以70升/分钟的速度单向循环输送。系统中集成了四个膜式腔室用于通气。除了对吸入麻醉剂进行呼气末反馈控制以及对氧气进行吸气闭环控制外，该系统还可在线记录流量、容积和呼吸压力，以及二氧化碳波形图和氧气消耗量。肺泡通气量和静态顺应性可轻松得出。当氧气输送降至临界值时，氧气消耗量的在线记录已被证明对于确定组织氧气供应的任何损害具有重要价值。上呼吸道或下呼吸道的阻塞可立即被检测到并加以区分。代谢紊乱，例如恶性高热，在危机前阶段即可被发现（氧气消耗量和二氧化碳产生量增加），并且可以在灾难性状况发生之前极早开始治疗。顺应性的记录只是持续可用的参数之一，这些参数可确保更好且充分地控制肺功能（例如早期检测到肺不张）。新开发的先进麻醉设备极大地扩展了人工通气的监测和呼吸诊断可能性，为（病理）生理学提供了新的见解，并能在早期检测到呼吸参数和代谢的紊乱。
