Yasuda N, Lockhart S H, Eger E I, Weiskopf R B, Liu J, Laster M, Taheri S, Peterson N A
Department of Anesthesia, University of California, San Francisco 94143-0464.
Anesth Analg. 1991 Mar;72(3):316-24. doi: 10.1213/00000539-199103000-00007.
The low solubility of sevoflurane in blood suggests that this agent should enter and leave the body more rapidly than isoflurane. However, the closeness of sevoflurane and isoflurane tissue/blood partition coefficients suggests that the rates of equilibration with and elimination from tissues should be similar. We tested both predictions, comparing sevoflurane with isoflurane and nitrous oxide in seven volunteers. We measured the rate at which the alveolar (end-tidal) (FA) concentration of nitrous oxide increased toward an inspired (FI) concentration of 65%-70%, then measured the concurrent rise in FA and mixed expired concentrations (FM) of sevoflurane and isoflurane at respective FI values of 1.0% sevoflurane and 0.6% isoflurane for 30 min. Minute ventilation (VE) was measured concurrently with the measurements of anesthetic concentrations. For the potent agents, we also measured VE, FA, and FM for 6-7 days of elimination. FA/FI values at 30 min of administration were as follows: nitrous oxide, 0.986 +/- 0.003 (mean +/- SD); sevoflurane, 0.850 +/- 0.018; and isoflurane, 0.733 +/- 0.027. FA/FA0 (FA0 = the last FA during administration) values after 5 min of elimination were as follows: sevoflurane, 0.157 +/- 0.020; isoflurane, 0.223 +/- 0.024. Recovery (volume of anesthetic recovered during elimination/volume taken up) of sevoflurane (101% +/- 7%) equaled recovery of isoflurane (101% +/- 6%). Time constants for a five-compartment mammillary model for sevoflurane were smaller than those for isoflurane for the lungs but were not different from isoflurane for the other compartments.(ABSTRACT TRUNCATED AT 250 WORDS)
七氟烷在血液中的低溶解度表明，该药物进出人体的速度应比异氟烷更快。然而，七氟烷与异氟烷的组织/血液分配系数相近，这表明它们在组织中达到平衡的速率以及从组织中消除的速率应该相似。我们在7名志愿者身上对这两个预测进行了测试，将七氟烷与异氟烷和氧化亚氮进行比较。我们测量了氧化亚氮的肺泡（呼气末）（FA）浓度向吸入（FI）浓度65%-70%升高的速率，然后在七氟烷FI值为1.0%、异氟烷FI值为0.6%的情况下，测量七氟烷和异氟烷在30分钟内FA和呼出混合气体浓度（FM）的同时升高情况。在测量麻醉剂浓度的同时测量分钟通气量（VE）。对于强效麻醉剂，我们还在消除6-7天的时间里测量了VE、FA和FM。给药30分钟时的FA/FI值如下：氧化亚氮，0.986±0.003（平均值±标准差）；七氟烷，0.850±0.018；异氟烷，0.733±0.027。消除5分钟后的FA/FA0（FA0=给药期间的最后一个FA）值如下：七氟烷，0.157±0.020；异氟烷，0.223±0.024。七氟烷的回收率（消除期间回收的麻醉剂体积/摄取的体积）为101%±7%，与异氟烷的回收率（101%±6%）相等。七氟烷五室乳头模型的时间常数在肺部比异氟烷小，但在其他腔室与异氟烷没有差异。（摘要截断于250字）
