論文ID: 09-0285
To evaluate the effects of IV fentanyl administration on end-tidal sevoflurane concentrations (ETSEVO) in throughbred racehorses, ETSEVO required for the internal fixation of longitudinal fractures were compared between the horses anesthetized with sevoflurane-fentanyl (Group SF; n=9) and those with sevoflurane alone (Group S; n=9). The loading dose of fentanyl (5.0 μg/kg) was administered over 15 min followed by the maintenance dose of fentanyl (0.1 μg/kg/min) throughout the operation in Group SF. Mean ETSEVO during operation in Group SF (2.6 ± 0.2%) were significantly lower than those in Group S (3.0 ± 0.3%). Plasma fentanyl concentrations (6.12 ± 0.88 ～ 7.78 ± 1.12 ng/ml) in 7 out of 9 horses in Group SF were stable and did not change significantly throughout the operation. Mean dobutamine infusion rate required for maintaining mean arterial blood pressure between 60 and 80 mmHg during operation in Group SF (0.56 ± 0.30 μg/kg/min) were significantly lower than those of Group S (0.90 ± 0.16 μg/kg/min). Qualities of the recoveries were clinically acceptable and serious complications were not observed in both groups. In conclusion, continuous IV fentanyl administration reduced sevoflurane requirement by 13% in thoroughbred racehorses undergoing orthopedic surgery, however fentanyl was considered to be less effective in horses compared to the other species.
