目的：通过对SD大鼠吸入不同浓度七氟烷麻醉不同时间后血中游离六氟异丙醇（hexafluoro-isopropanol, HFIP）浓度的测定，分析血中游离HFIP的生成规律及其与七氟烷麻醉浓度的关系。方法：选择114只健康成年SD大鼠，其中6只用于测定HFIP样品的血/气分配系数，其余108只随机分为三组，每组36只，分别接受1.16% (S1组)、2.32% (S2组)和3.48% (S3组)浓度的七氟烷麻醉。每组内再分为6个麻醉时段，分别麻醉0.5 h, 1.0 h, 1.5 h, 2.0 h, 3.0 h和4.0 h，每个时段用鼠6只。麻醉结束后立即取腹主动脉血5-10 mL。首先采用顶空二次平衡法测得HFIP样品的血/气分配系数，再使用一次平衡法测得麻醉大鼠血中实际游离HFIP浓度。同时使用顶空二次平衡法测定麻醉大鼠血中七氟烷浓度及血/气分配系数。分析组内血中游离HFIP浓度与麻醉时间的关系，及组间七氟烷麻醉浓度与血中游离HFIP浓度的关系。结果：三组不同时点SD大鼠血中均能测出游离HFIP，且在麻醉1.0 h时均达峰值，而后随着麻醉时间的延长，其浓度逐渐降低。与S1组相比，S2组各对应时点血中游离HFIP浓度均增高（P < 0.05）；除4.0 h时点外，S3组各对应时点血中游离HFIP浓度却无显著性差异（P > 0.05）。与S2组相比，S3组各对应时点血中游离HFIP浓度均显著降低（P < 0.05）。结论：各组大鼠血中游离HFIP浓度均随七氟烷麻醉时间的延长呈先增高后降低的趋势。当七氟烷麻醉浓度增加到3.48%时，血中各时点游离HFIP浓度反而降低，七氟烷代谢受到抑制。
Objective: Though determining the free hexafluoro-isopropanol (HFIP) concentration in blood when SD rats had been anesthetized with different sevoflurane concentrations for different time, to observe the change of free HFIP concentration in rats’ blood, and analyze the relationship between inhaled sevoflurane concentration and free HFIP concentration in blood among the three groups. Methods: One hundred and fourteen healthy adult SD rats were selected, in which 6 rats were used to determine the blood/gas partition coefficient (B/G) of HFIP, and the rest 108 rats were randomly divided into three groups (S1, S2 and S3) with 36 rats in each group, and anesthetized by sevoflurane with different concentrations (1.16%, 2.32% and 3.48%), respectively. Every 6 rats in each group were accepted anesthesia by inhaled sevoflurane with a preset concentration for 0.5 1.0, 1.5, 2.0, 3.0 and 4.0 h, respectively. First, the blood/gas partition coefficient of HFIP samples was measured by the two-stage headspace equilibration, and then the actual free HFIP concentration in the blood of anesthetized rats was measured by the one-stage headspace equilibration. At the same time, the sevoflurane concentration and blood/gas partition coefficient in the blood of anesthetized rats were determined by the two-stage headspace equilibrium method. Both the curves of free HFIP concentration in blood and inhaled sevoflurane concentration vs. anesthesia time were made, and the relationship among them was analyzed. Results: Free HFIP can be detected and its peak value occurred at 1.0 hr after inhaled sevoflurane anesthesia in each group, and after that decreased along with the prolong of anesthesia time. Compared with group S1, the free HFIP concentration in group S2 was higher at each corresponding time point (P < 0.05), but except for the time point of 4.0 h, no significant differences were found in group S3 at corresponding time points (P > 0.05). Compared with group S2, the free HFIP concentration in group S3 was significantly lower at each corresponding time point (P < 0.05). Conclusion: The free HFIP concentration in blood showed a tendency from initial increase to subsequent decrease with the prolongation of sevoflurane anesthesia time. When the inhaled sevoflurane concentration increased to 3.48%, the generation of free HFIP was decreased and the metabolism of sevoflurane was inhibited.