The Effects of Intravenous Thiopental Injection on Jugular Venous Oxygen Saturation (SjVO2) during Cerebral Aneurysm Surgery

Abstract

Background: Thiopental has a profound impact on the cardiovascular system. The effects of hemodynamics after intravenous thiopental on the balance of cerebral metabolism with cerebral blood flow is unknown. The purpose of this study was to monitor hemodynamic change, cerebral arterial-jugular venous oxygen content difference (AVDO2) and jugular venous oxygen saturation (SjVO2) after a thiopental injection for brain protection during cerebral aneurysm surgery.

Methods: Twenty patients received a standard anesthetic consisting of isoflurane, vecuronium and fentanyl with a PaCO2 of 30⁣35 mmHg. Hemodynamics, arterial and jugular venous blood gases were measured at 3 time points: I; Just before thiopental injection; II; Electroencephalographic (EEG) burst suppression after a 4⁣5 mg/kg intravenous thiopental injection; and III; EEG recovery.

Results: Intravenous thiopental (4⁣5 mg/kg) induced an EEG burst suppression for 6.5 ⁑ 1.7 minutes. Hemodynamics and arterial blood gas analysis were not significantly different among the different time points, but mean arterial pressure (68.4 ⁑ 7.2 mmHg) and systemic vascular resistance (1027.0 ⁑ 300.9 dynes·sec/cm5) in II were significantly (P ＜ 0.05) decreased compared with I (84.3 ⁑ 9.6, 1169.1 ⁑ 304.5) and III (89.1 ⁑ 10.6, 1288.6 ⁑ 426.1). SjVO2 (71.6 ⁑ 11.8%) was significantly (p ＜ 0.05) decreased within the normal value compared with I (75.1 ⁑ 5.6) and III (76.1 ⁑ 10.1), but AVDO2 was not significantly different among the 3 time points. There was no evidence of cerebral ischemia or infarction in computed tomographic (CT) findings of the 20 patients after surgery.

Conclusions: Hemodynamics after 4⁣5 mg/kg intravenous thiopental do not modify the balance of cerebral oxygen metabolism with cerebral blood flow in patients undergoing cerebral aneurysm surgery.