Outcome measures
blood loss, Bleeding, bleeding
BLOOD LOSS, BLEEDING, BLEEDING
Amount of intraoperative surgical bleeding, transfusion requirement, surgeon satisfaction, hemodynamic parameters, heart rate, blood pressure, and duration of surgery were measured. The amount of bleeding was estimated and registered based on the number of completely impregnated gauze pieces (15 cc for each 4 × 4 cm, and 50 cc for each 30 × 30 cm gauze piece), and the amount of blood in the suction bottle.Transfusion threshold was based on MABL (maximum allowable blood loss) during surgery or Hb < 9 after that. Bleeding less than MABL was replaced with three times the Ringer's lactate volume. Further blood loss was replaced with transfusions of red blood cells.Desirability of surgical field was recorded by the surgeon as good, moderate, or weak. Hemodynamic variables were recorded before the induction, after the intubation, after changing to prone position, every 15 min during the operation, at the end of surgery, after extubation, and before leaving the recovery unit. The surgeon and the staff who measured and recorded the hemodynamic variables were blinded to the mode of ventilation.