Jones R M, Cashman J N, Eger E I, Damask M C, Johnson B H
Department of Anaesthetics, Guy's Hospital, University of London, England.
Anesth Analg. 1990 Jan;70(1):3-7. doi: 10.1213/00000539-199001000-00002.
The inhalation anesthetic, desflurance (I-653), is a methyl ethyl ether halogenated entirely with fluorine and differing from isoflurance only in the substitution of fluorine for chlorine on the alpha-ethyl carbon. Relative to presently used potent inhalation anesthetics, desflurane has low blood/gas (0.42) and oil/gas (18.7) partition coefficients. These indicate that it will undergo rapid washin and washout (and hence rapid induction of and recovery from anesthesia) and have a MAC value of about 5%. In the present study we demonstrate that desflurane possesses these characteristics in healthy young volunteers. After a 10-min exposure to desflurane the ratio of alveolar (FA) (determined by end-tidal sampling) to inspired (FI) concentration (FA/FI) was 0.82. Washout was similarly rapid; 10 min after discontinuing administration of desflurane, the alveolar concentration relative to the last concentration during administration of anesthetic (FAO) was 0.11 (FA/FAO). These values are similar to those for nitrous oxide. Volunteers responded to commands an average of 2.7 min after discontinuing anesthetic administration. The values for MAC-awake and MAC (the latter determined by tetanic stimulation of the ulnar nerve using surface electrodes) were 2.42% and 4.58% and the ratio of the former to the latter was 0.53.
吸入麻醉药地氟烷（I - 653）是一种完全由氟取代的甲基乙基醚，与异氟烷的区别仅在于α - 乙基碳上的氯被氟取代。相对于目前使用的强效吸入麻醉药，地氟烷具有较低的血/气（0.42）和油/气（18.7）分配系数。这些表明它将经历快速的吸入和呼出（从而快速诱导麻醉和从麻醉中恢复），并且其最低肺泡有效浓度（MAC）值约为5%。在本研究中，我们证明地氟烷在健康年轻志愿者中具有这些特性。在接触地氟烷10分钟后，肺泡（通过呼气末采样测定）与吸入（FI）浓度的比值（FA/FI）为0.82。呼出同样迅速；停止给予地氟烷10分钟后，相对于麻醉给药期间的最后浓度（FAO）的肺泡浓度为0.11（FA/FAO）。这些值与氧化亚氮的值相似。志愿者在停止麻醉给药后平均2.7分钟就能对指令做出反应。清醒时的MAC值和MAC（后者通过使用表面电极对尺神经进行强直刺激来测定）分别为2.42%和4.58%，前者与后者的比值为0.53。
