Effect of Rapid Plasma Volume Expansion during Anesthesia Induction on Haemodynamics and Oxygen Balance in Patients Undergoing Gastrointestinal Surgery

Aims: To investigate the reasonable dose of Voluven for rapid plasma volume expansion during the anaesthesia induction patients receiving gastrointestinal surgery. Methods: Sixty patients were randomly divided into three groups (n=20): Group A (5 ml/kg), Group B (7 ml/kg) and Group C (9 ml/kg). HES 130/0.4 was intravenously transfused at a rate of 0.3 ml/kg/min) at 30 min before anaesthesia induction. Besides standard haemodynamic monitoring, cardiac index (CI), systemic vascular resistance index (SVRI) and stroke volume variation (SVV) was continuously detected with the FloTrac/Vigileo system. Haemodynamic variables were recorded immediately before fluid transfusion (T(0)), immediately before induction (T(1)), immediately before intubation (T(2)), immediately after intubation (T(3)) and 5 min, 10 min, 20 min and 60 min after intubation (T(4)-T(7)). Arterial and venous blood was collected for blood gas analysis, Hb and Hct before volume expansion (t(0)), immediately after volume expansion (t(1)) and at 1 h after volume expansion (t(2)). Oxygen delivery (DO(2)), oxygen extraction ratio (ERO(2)) and volume expansion rate were calculated. Results: 1) MAP and CI decreased in Group A in T(2)~T(7) and remained changed in Group B and C. 2) CVP increased in three groups after fluid infusion without significant difference. 3) The decrease in SVRI was more obvious in Group B and C than that in Group A after induction and more obvious in Group C than in Group B in T(2)-T(4 )and T(6)~T(7). 4) SVV was lower in Group B and C than that in Group A after intubation, and lower in Group C than that in Group B in T(3)-T(6). 5) Hb and Hct decreased after fluid infusion, and the decrease in Hb and Hct was in the order of C>B>A. 6) Volume expansion rate was in the order of C>B>A. 7) ScvO(2), PaO(2) and DO(2) increased in three groups after fluid infusion and the increase in DO(2 )was in the order of C>B>A. Conclusions: Rapid plasma volume expansion with Voluven at 7-9 ml/kg can prevent haemodynamic fluctuation during anaesthesia induction, maintain the balance between oxygen supply and oxygen consumption during gastrointestinal surgery, and Voluven at 9 ml/kg can improve the oxygen delivery.