Targ A G, Yasuda N, Eger E I
Department of Anesthesia, University of California, San Francisco 94143-0464.
Anesth Analg. 1989 Aug;69(2):218-25.
This study defines some characteristics of a standard anesthetic circuit that may impede anesthetic induction and recovery with I-653, sevoflurane, isoflurane, and halothane. Partition coefficients for anesthetic circuit components (masks, bellows, bags, airways, and circuit tubes) consistently ranked halothane greater than isoflurane greater than sevoflurane greater than I-653, suggesting a reverse order of washin and washout rates for an anesthetic circuit constructed from similar components. Consistent with this prediction, the concentrations of I-653 increased and decreased more rapidly than those of the other agents at any flow rate during washin (0.5, 1, or 2 L/min gas inflow rates) or washout (1, 3, or 5 L/min) in a conventional anesthetic circuit. The rates of change in I-653 concentration closely approximated the maximal possible theoretical rates. Our results suggest that absorption of I-653 by circuit components or soda lime should not hinder induction of or recovery from anesthesia.
本研究确定了标准麻醉回路的一些特性，这些特性可能会妨碍使用I - 653、七氟烷、异氟烷和氟烷进行麻醉诱导和苏醒。麻醉回路组件（面罩、波纹管、贮气囊、气道和回路管道）的分配系数始终显示氟烷大于异氟烷大于七氟烷大于I - 653，这表明由类似组件构成的麻醉回路的吸入和呼出速率顺序相反。与该预测一致，在传统麻醉回路中，在吸入阶段（气体流入速率为0.5、1或2 L/分钟）或呼出阶段（1、3或5 L/分钟）的任何流速下，I - 653浓度的升高和降低都比其他药物更快。I - 653浓度的变化速率非常接近最大可能的理论速率。我们的结果表明，回路组件或碱石灰对I - 653的吸收不应妨碍麻醉诱导或苏醒。
