ABSTRACT
20 % . In both groups CH was induced with infusion of 0.01 % NTP at a rate 0.5-6.0 ?g?kg-1?min-1 to maintain MAP at 55-65 mm Hg. MAP, HR, CVP and CO were continuously monitored. Arterial lactate concentration was measured by enzyme assay. Arterial and mixed venous blood gases were analyzed, and oxygen delivery (DO2 ) and consumption (VO2) were calculated before AHH (T0) after AHH was performed (T1), 30 min after CH was induced (T2) and 30 min after termination of CH (T3) in group Ⅰ and in group Ⅱ before CH (T1), 30 min after induction of CH (T2) and 30 rain after termination of CH (T3 ) .ResultsIn group Ⅰ(AHH + CH) compared with the baseline values (T0 ) HR significantly decreased while CVP significantly increased after AHH (T1 ) ; cardiac output (CO) significantly increased after AHH (T1 ) and during CH (T2) while DO2 was significantly decreased after AHH (T1) and CH (T3 ) but arterial lactate concentration was significantly decreased during and after CH (T2, T3). In group Ⅱ (CH alone) compared with the baseline values (T1) HR significantly increased while CVP significantly decreased during and after CH (T2, T3 ) ; there was no significant change in CO and DO2 at T2 and T3 but arterial lactate concentration significantly increased during and after CH (T2, T3). There was significantly less blood loss during operation in group I than in group Ⅱ . ConclusionThere was tissue deoxygenation during and after deliberate hypotension as shown by increased arterial lactate concentration while AHH combined with CH can improve tissue perfusion and oxygenation. AHH can also maintain hemodynamic stability during CH.