During the postoperative 48 h , there was marked reduction in morphine requirements in Group B compared to Group C , ( 8.6 0.94 mg vs. 18.83 3.4 mg respectively , P = 0.2 ) , lower postoperative pain scores , shorter extubation time ( 117 10 min vs. 195 19 min , respectively , P = 0.03 ) , better respiratory parameters ( PaO 2 / FiO 2 , PaCO 2 and pH ) , with no incidence of wound infection , no differences in ICU or hospital stay duration .