The aim of the present study was to investigate the effect of fat-tail on metabolism of inhalation anesthesia in fat-tailed sheep and those with ligated median sacral artery (MSA). Twelve healthy, 9-12-month- old female sheep were used in this study. After mask induction anesthesia with isoflurane in 100% oxygen. Serum fluoride concentration (SFC) was measured 0,1,3,6,12,24,48 and 72 h post-anesthesia. Prior to starting the second step of anesthesia (after two weeks), MSA of sheep in the experimental group was ligated under epidural anesthesia. Results:In the second step of anesthesia, increase in SFC level in sheep with unligated MSA was similar to that observed in the first step. Concentration of this ion in the experimental group was significantly reduced 3, 6, 12 and 24 hrs after induction of anesthesia, compared to that in the control group and the first step of the anesthesia. Conclusion: The fat in the tail absorbs more isoflurane which is slowly released into the general circulation after administration of anesthetic is discontinued, resulting in prolonged elevated concentration of isoflurane.
Siavash Sharifi and Ahmadreza Mohammadnia