Caudal epidural injection of lidocaine, tramadol, and lidocaine-tramadol for epidural anesthesia in cattle.

Caudal epidural anesthesia is commonly utilized in veterinary medicine to allow diagnostic, obstetrical, and surgical intervention, in the perineal region of large animal. The aim of this study is to directly compare the time of onset and duration of analgesia produced by a tramadol and lidocaine-tramadol combination with that produced by lidocaine administration in the epidural space of Cattle. Five healthy adult Holstein dairy cows were selected to this study. Epidural anesthesia was produced in all cows by lidocaine, with 2 weeks intervals repeated by a combination of lidocaine-tramadol and tramadol. Time to onset and duration of analgesia were recorded. Heart rate, respiratory rate and body temperature were recorded at 0 min and at 5, 10, 15, 30, 60, and 75 min after the epidural administrations of each treatments. The tramadol produced a significant (P < 0.05) longer duration of analgesia (306.8 ± 8.58 min) than lidocaine (69.40 ± 8.96 min) alone and lidocaine-tramadol combination (174 ± 4.84 min). Also, lidocaine-tramadol combination produced a significant (P < 0.05) longer duration of analgesia than lidocaine alone. Complete analgesia began at 14.10 ± 1.57 min in the tramadol treatment, being more delayed than in the treatments with lidocaine-tramadol (4.84 ± 0.68 min) and lidocaine (3.90 ± 0.89 min). Body temperatures, heart rates, and respiratory rates were not significantly different in comparison with baseline values throughout the study in the all treatments. The combination of lidocaine-tramadol produced anesthesia of longer duration than lidocaine and the onset time was approximately same as for the lidocaine group. Utilizing this combination, long duration of anesthesia could commence relatively soon after epidural injection and might be used without re-administration of anesthetic agent in long-duration obstetrical and surgical procedures.