Comparative effects of preemptive Tramadol and Pentazocine administration in dogs undergoing ventral midline laparotomy surgical procedures

Ventral midline laparotomy surgery in dogs is regarded as a painful surgery with higher pain score and lower nociceptive threshold. This study evaluated the comparative effects of preoperative tramadol or pentazocine administration in dogs undergoing ventral midline laparotomy surgical procedures. Ten bitches were randomly allocated into two groups containing 5 dogs each. The bitches in each group were made to undergo either gastrotomy or ovriohysterectomy surgery. Group 1 received intarmuscular injection of 2mg/kg Pentazocine while group 2 received 2mg/kg Tramadol HCl intramuscularly 15 minutes before premedication with Xylazine (1mg/kg IM) and atropine (0.04mg/kg IM) while anaesthetic induction was achieved with intravenous administration of Ketamine (10mg/kg) and Diazepam (0.25mg/kg). Cardiopulmonary and anaesthetic parameters were monitored for 90 minutes while antinociception was also assessed by pedal withdrawal reflex. Data between the two groups were compared using independent sample T-test and values of P ≤ 0.05 were considered significant. The quality of anaesthesia was better in the tramadol group with longer duration of antinociception (48.00±5.08minutes) compared to the pentazocine group (40.20±5.17minutes) which is not statistically significant (p>0.05). The TSD was significantly longer in the tramadol group (33.80±10.71min) compared to the pentazocine group (7.00±4.36min). The anaesthetic parameters did not differ significantly (p>0.05) between the pentazocine and tramadol group. There was no significant effect of anaesthesia on the cardiopulmonary parameters measured in both groups. Even though tramadol provide longer duration of antinociception, pentazocine is an alternative replacement in dogs undergoing laparotomy especially in developing countries where there is limited access to tramadol.