Group III with 0.3mg morphine had the longest postoperative analgesia time: 29.87 ± 7.00 hours, followed by group II with 0.2mg morphine of 22.33 ± 4.44 hours and the lowest was group I with 0.1mg morphine of 18.28 ± 3.86 hours, the difference had statistically meaning with p <0.05.