In the preoperative embolization group and conventional surgery group , the blood loss was 912 ml vs. 2 500 ml ( P < 0.001 ) , the blood transfusion was 1 000 ml vs. 2 600 ml ( P < 0.001 ) , the operation time was 4.1 h vs. 5.9 h ( P < 0.001 ) , and the length of hospital stay was 12.5 d vs. 19.8 d ( P < 0.001 ) .