Microcirculatory effects of hyperglycemia on retinal ischemia

由于异丙酚麻醉在眼科手术中比吸入麻醉有许多优点，我们决定在兔眼缺血模型中研究异丙酚和氟烷麻醉对视网膜循环和功能的影响。方法：用异丙酚（异丙酚组，n=8）或氟烷（氟烷组，n=9）深度麻醉17只双侧结扎颈动脉的荷兰兔，致视网膜不完全缺血，平均动脉压为40 mmHg。我们通过扫描激光检眼镜染色稀释技术评估视网膜循环，并通过检测基线、深度和恢复麻醉60 min时视网膜电图b波振幅来评估视网膜功能。结果：两组脑电b波振幅变化相似。在深度麻醉时，异丙酚组和氟烷组的振幅分别下降到基线值的63%和54%，并在麻醉时完全恢复。深麻醉时，异丙酚组眼压下降，仍低于基线值，氟烷组保持不变。两组深度麻醉时视网膜节段血流量均减少。异丙酚组在恢复麻醉期间升高，氟烷组仍降低。结论：与氟烷相比，本研究未发现异丙酚对视网膜缺血性损伤有明显保护作用的证据。异丙酚麻醉的特点是持续的低IOP和迅速恢复视网膜血流量。这些可能是用于眼科手术的麻醉剂的合适特征。方法：用异丙酚（异丙酚组，n=8）或氟烷（氟烷组，n=9）深度麻醉17只双侧结扎颈动脉的荷兰兔，致视网膜不完全缺血，平均动脉压为40 mmHg。我们通过扫描激光检眼镜染色稀释技术评估视网膜循环，并通过检测基线、深度和恢复麻醉60 min时视网膜电图b波振幅来评估视网膜功能。结果：两组脑电b波振幅变化相似。在深度麻醉时，异丙酚组和氟烷组的振幅分别下降到基线值的63%和54%，在恢复麻醉时，两组的振幅都完全恢复。深麻醉时，异丙酚组眼压下降，仍低于基线值，氟烷组保持不变。两组深度麻醉时视网膜节段血流量均减少。异丙酚组在恢复麻醉期间升高，氟烷组仍降低。结论：与氟烷相比，本研究未发现异丙酚对视网膜缺血性损伤有明显保护作用的证据。异丙酚麻醉的特点是持续的低IOP和迅速恢复视网膜血流量。这些可能是用于眼科手术的麻醉剂的合适特征。结果：两组脑电b波振幅变化相似。在深度麻醉时，异丙酚组和氟烷组的振幅分别下降到基线值的63%和54%，在恢复麻醉时，两组的振幅都完全恢复。深麻醉时，异丙酚组眼压下降，仍低于基线值，氟烷组保持不变。两组深度麻醉时视网膜节段血流量均减少。异丙酚组在恢复麻醉期间升高，氟烷组仍降低。结论：与氟烷相比，本研究未发现异丙酚对视网膜缺血性损伤有明显保护作用的证据。异丙酚麻醉的特点是持续的低IOP和迅速恢复视网膜血流量。这些可能是用于眼科手术的麻醉剂的合适特征。结论：与氟烷相比，本研究未发现异丙酚对视网膜缺血性损伤有明显保护作用的证据。异丙酚麻醉的特点是持续的低IOP和迅速恢复视网膜血流量。这些可能是用于眼科手术的麻醉剂的合适特征。少

Because propofol based anesthesia has several advantages over inhalational anesthetics for ophthalmic surgery, we decided to investigate the effects of propofol and halothane anesthesia on retinal circulation and function in a rabbit model of ocular ischemia. Methods : Incomplete retinal ischemia was induced in 17 pigmented Dutch rabbits with bilaterally ligated carotid arteries by deep anesthesia with propofol (propofol group, n=8) or by halothane (halothane group, n=9) to a mean arterial pressure of 40 mmHg. We evaluated retinal circulation by means of the dye dilution technique with a scanning laser ophthalmoscope and retinal function by examining the electroretinogram b-wave amplitude at the end of 60 min baseline, deep and recovery anesthesia. Results : Similar changes in ERG b-wave amplitudes were noted in both groups. The amplitudes in the propofol and halothane group decreased respectively to 63 % and 54 % of their baseline values during deep anesthesia, and fully recovered dur … More ing recovery anesthesia in both groups. Intraocular pressure in the propofol group decreased during deep anesthesia and remained less than the baseline value, while in the halothane group it remained unchanged. Segment retinal blood flow decreased in both groups during deep anesthesia. It increased during recovery anesthesia in the propofol group, but remained decreased in the halothane group. Conclusion : Evidence of the distinctive protective effects of propofol against ischemic injury to the retina could not be found in this study, when compared with halothane. Propofol anesthesia is characterized by a sustained lower IOP and prompt recovery of retinal blood flow. These may be suitable features for an anesthetic used for ophthalmic surgery.Methods : Incomplete retinal ischemia was induced in 17 pigmented Dutch rabbits with bilaterally ligated carotid arteries by deep anesthesia with propofol (propofol group, n=8) or by halothane (halothane group, n=9) to a mean arterial pressure of 40 mmHg. We evaluated retinal circulation by means of the dye dilution technique with a scanning laser ophthalmoscope and retinal function by examining the electroretinogram b-wave amplitude at the end of 60 min baseline, deep and recovery anesthesia. Results : Similar changes in ERG b-wave amplitudes were noted in both groups. The amplitudes in the propofol and halothane group decreased respectively to 63 % and 54 % of their baseline values during deep anesthesia, and fully recovered during recovery anesthesia in both groups. Intraocular pressure in the propofol group decreased during deep anesthesia and remained less than the baseline value, while in the halothane group it remained unchanged. Segment retinal blood flow decreased in both groups during deep anesthesia. It increased during recovery anesthesia in the propofol group, but remained decreased in the halothane group. Conclusion : Evidence of the distinctive protective effects of propofol against ischemic injury to the retina could not be found in this study, when compared with halothane. Propofol anesthesia is characterized by a sustained lower IOP and prompt recovery of retinal blood flow. These may be suitable features for an anesthetic used for ophthalmic surgery.Results : Similar changes in ERG b-wave amplitudes were noted in both groups. The amplitudes in the propofol and halothane group decreased respectively to 63 % and 54 % of their baseline values during deep anesthesia, and fully recovered during recovery anesthesia in both groups. Intraocular pressure in the propofol group decreased during deep anesthesia and remained less than the baseline value, while in the halothane group it remained unchanged. Segment retinal blood flow decreased in both groups during deep anesthesia. It increased during recovery anesthesia in the propofol group, but remained decreased in the halothane group. Conclusion : Evidence of the distinctive protective effects of propofol against ischemic injury to the retina could not be found in this study, when compared with halothane. Propofol anesthesia is characterized by a sustained lower IOP and prompt recovery of retinal blood flow. These may be suitable features for an anesthetic used for ophthalmic surgery.Conclusion : Evidence of the distinctive protective effects of propofol against ischemic injury to the retina could not be found in this study, when compared with halothane. Propofol anesthesia is characterized by a sustained lower IOP and prompt recovery of retinal blood flow. These may be suitable features for an anesthetic used for ophthalmic surgery. Less