Group B

(n = 48)

Group M

(n = 48)

P value

Intra-operative fentanyl (µg) consumption

104.17 ± 20.19

102.08 ± 14.43

0.56

Time of 1^st request of analgesia (hours)

6.48 ± 1.11

7.29 ± 1.34

0.002*

Total pethidine consumption in the first 24 h (mg) post-operative

43.75 ± 11.18

30.31 ± 8.84

<0.001**