Effects of thoracic epidural anesthesia on systemic oxygen supply-demand relationship during one-lung ventilation
- VernacularTitle:胸段硬膜外麻醉复合全麻对开胸单肺通气患者氧代谢的影响
- Author:
Yi FENG
;
Ying SUN
;
Baxian YANG
- Publication Type:Journal Article
- Keywords:
Anesthesia,epidural;
Anesthesia,general;
Pulmonary ventilation;
Oxygen consumption
- From:
Chinese Journal of Anesthesiology
1995;0(10):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To assess the influence of upper thoracic epidural anesthesia (TEA) on systemic oxygen supply-demand relationship during one-lung ventilation (OLV). Methods Twenty ASA Ⅰ-Ⅲ patients undergoing elective esophageal surgery were randomly divided into 2 groups : group Ⅰ general anesthesia (GI n = 10) and group Ⅱ combined general-epidural anesthesia (GIE n = 10). In both groups anesthesia was induced with propofol 1.5-2.0 mg?kg-1, fentanyl 3 ?g?kg-1 and vecuronium 0.1 mg?kg-1. The patients were intubated with double-lumen catheter. Correct positioning was verified by auscultation and fiberoptic bronchoscopy. Anesthesia was maintained with isoflurane (1.5-2.0% ) and intermittent i. v. boluses of fentanyl. BIS was maintained at 45-55 during operation. In GIE group epidural puncture was performed at T7-8 or T8-9. The catheter was advanced 3.5-4.0 ml in the epidural space cephalad. 0.5% ropivacaine was infused at 3-5 ml?h-1 during operation. Anesthetic block levels ranged from T2-4 to T10-12 . Radial artery was cannulated for BP monitoring and blood sampling and Swan-Ganz catheter was positioned in the pulmonary artery via right internal jugular vein. ECG, MAP, HR, CVP, continuous cardiac output index (CCI) and BIS were continuously monitored during anesthesia. Arterial and mixed venous blood samples were obtained before induction of anesthesia (T0 ), 30 min after intubation while two lungs were being ventilated (T1) at 15, 30, 60 and 120 min of OLV (T2-3) and 30 min after TLV was resumed (T6 ) . MAP, CVP, cardiac output index (CI) and arterial and mixed venous blood oxygen content were measured and oxygen supply (DO2) and consumption (VO2) were calculated at each time point. Results In GIE group MAP was significantly lower than that in GI group ( P 0.05). At 15, 30 and 60 min of OLV (T2-4) mixed venous oxygen saturation (SVO2 ) was significantly lower while VO2 significantly higher in group GIE than in group GI. Consequently DO2/ VO2 in group GIE was significantly lower than that in group GI. Conclusion Thoracic epidural anesthesia combined with general anesthesia increases oxygen consumption (VO2) and consequently decreases DO2/ VO2 during OLV.
