ABSTRACT
objective To investigate the changes in angiotensin-Ⅱ (AT-Ⅱ), endothelin (ET) andcalcitonin gene-related peptide (CGRP) during clipping of intracranial aneurysm performed under desfiuraneanesthesia. Methods Forty-five ASAⅠ -Ⅱ patients (20 male, 25 female) aged 14-66yr undergoing electiveclipping of intracranial aneurysm two weeks after acute subarachnoid bleeding. Anesthesia was induced withmidazolam 0 .05 mg?kg~(-1), fentanyl 2?g?kg~(-1), propofol 2 mg?kg~(-1) and vecuronium 0.1 mg?kg~(-1). The patientswere mechanically ventilated after tracheal intubation and P_(ET)CO_2 was maintained at 30-35 mm Hg. Anesthesia wasmaintained with desflurane at 1 .0-1 .5 MAC with low flow (0.3-0.5 L?min~(-1) ) supplemented with intermittentintravenous boluses of vecuronium. Radial artery was cannulated for direct continuous BP monitoring. ECG, HR,SPO_2 and P_(ET) CO_2 were continuous monitored during operation. Blood samples were taken before induction ofanesthesia (T_1, baseline), when dura was opened (T_2 ), while aneurysm was being clipped (T_3 ) and 30 min afterclipping for determination of plasma concentrations of AT-Ⅱ, ET and CGRP. Results Plasma concentration ofAT-Ⅱ did not change significandy throughout the surgery. Plasma ET concentration decreased significantly at T_2and T_3 compared with the baseline (P