There was no difference of VAS score under quiet state , but under the motion state the VAS scores declined significantly , the total amount of morphine reduced [ ( 5.2 1.2 ) vs ( 13.9 1.6 ) mg ) ] , the cases of nausea , vomiting , pruritus , orthostatic hypotension decreased and the postoperative first anal exhaust time interval shortened ( P < 0.05 ) .