Microcirculatory effects of hyperglycemia on retinal ischemia

2000 Fiscal Year Final Research Report Summary

• Project/Area Number: 11470331
• Research Category: Grant-in-Aid for Scientific Research (B).
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Anesthesiology/Resuscitation studies
• Research Institution: KAWASAKI MEDICAL SCHOOL
• Principal Investigator: FUJITA Yoshihisa Kawasaki Medical School, Anesthesiology, Asociate Professor, 医学部, 助教授 (10144263)
• Co-Investigator(Kenkyū-buntansha): ENDO Sumiko Kawasaki Medical School, Anesthesiology, Faculty Assistant, 医学部, 助手 (90278945) ; KIMURA Kenichi Kawasaki Medical School, Anesthesiology, Assistant Professor, 医学部, 講師 (90214874)
• Project Period (FY): 1999 – 2000
• Keywords: microcirculation / retina / fluorescein microscope / ischemia / reperfusion / anesthetics / halothane / propofol

Research Abstract

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 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.