Enhancing analgesic effects of lidocaine in rabbit epidural analgesia using metoclopramide or tramadol

The objective of the present experience was to study the effects of metoclopramide and tramadol on epidural analgesia induced by lidocaine in rabbits.Fifteen healthy New Zealand White rabbits weighting 3-3.5 kg of both genders were used.Animals were divided randomly into three groups. Three different combinations of drugs were injected into the epidural space to induce epidural analgesia in the following order: group A2% lidocaine (1.5 ml), group B the combination of 2% lidocaine (1.5 ml) and metoclopramide (0.5 ml) and group C, the combination of 2% lidocaine (1.5 ml) and tramadol (0.2 ml). The procedure was repeated 48 hours and a week after the first injection. The onset time of analgesia (OT), duration of flaccid paresis (DFP) and duration of analgesia (DA) was determined in all treatments. There was no complication in the induction of epidural analgesia.Statistical analysis showed thatmean of OT in group C (15.7±4.2 sec), was significantly lower in comparison to group A (68.6±15.5 sec) and group B (45.8±17.1 sec)(p=0.004). Mean DFP was significantly higher in group C (35.9±10.5 min) in comparison to group A (18.3±5.2 min) and group B (29.2±11.5 min)( p =0.001). Mean of DA was significantly higher in group B (39.1±16.2 min) compared to group A (23.6±5.5 min)(p=0.018) and also in group C (48.9±10.7 min) compared to group A (p =0.00). But there was no significant difference between means of DA in group B and C (p =0.05).The present study indicates that addition ofmetoclopramide and tramadol to lidocaine is effective in prolongation of epidural analgesia in rabbit.