Background  Postoperative fatigue syndrome (POFS) is defined as a series of clinical symptoms, such as muscle weakness, sleeplessness or drowsiness, and inattention, during the course of surgical rehabilitation. It is not only one of the most important postoperative complications, but also can lead to other complications, which is one of the main factors affecting rapid recovery of patients. Ideal animal models are of great significance for the study of the etiology and prevention and treatment of POFS. However, the method of anesthesia in the model of POFS is relative single.

  Objective  To evaluate the feasibility and effect of isoflurane inhalation anesthesia in 70% hepatectomy for establishing POFS model.

  Methods   SPF healthy male mice were randomly divided into four groups according to baseline of spontaneous activity and body weight, including the normal control group (CON, n=8) , isoflurane anesthesia sham operation group (ISO sham, n=8), isoflurane anesthesia model group (ISO PHx, n=8) and pentobarbital sodium anesthesia model group (NEMB PHx, n=8). The postoperative fatigue syndrome model was established by 70% hepatectomy. The observation indexes included the induction time and recovery time. General conditions of the animals were observed and recorded from day 0 to 7 after operation, including body weight, hair score, squinting score and food intake. Open field experiment was conducted on the day 0, 1, 3, 5 and 6 after operation, and treadmill test was conducted on the day 5 to evaluate the level of postoperative spontaneous activity and exercise endurance of the mice in each group.

  Results  Anesthesia induction time and recovery time were shorter in the ISO PHx group than those in the NEMB PHx group (0.95 ± 0.27min vs 3.65 ± 0.63 min; 1.85 ± 0.94 min vs 205.57 ± 27.95 min, P ＜ 0.001). Compared with the NEMB PHX group, the postoperative squint score (0 vs 1.22 ± 0.36) and the hair score (D1: 0.25 ± 0.08 vs 0.03 ± 0.03; D2: 0.22 ± 0.05 vs 0.03 ± 0.03) were also significantly lower (all P ＜ 0.001). Compared with CON group, the body weight in the ISO PHx group and the NEMB PHx group decreased on day 1, 2, 3 and 4 postoperatively (NEMB PHx group P ＜ 0.05), the open-filed spontaneous activity decreased significantly on day 0, 1 and 3 (P ＜ 0.01) and the distance of treadmill test decreased significantly on day 5 postoperatively (P ＜ 0.05), the spontaneous activity decreased significantly after the treadmill test. There was no significant difference in spontaneous activity between ISO PHx group and NEMB PHx group after treadmill test( P ＜ 0.01).

  Conclusion  Isoflurane inhalation anesthesia can be used as an effective anesthesia method for the establishment of 70% hepatectomy animal model of POFS, with the advantages of rapid induction, adjustable depth of anesthesia, rapid recovery and so on.