Postoperative analgesic comparison of tramadol or epidural morphine in sheep submitted to cesarean section

Abstract

Sense, the ability to feel, encompasses all vertebrate animals. However, ruminants, particularly sheep, are relatively stoic beings, showing no obvious signs of anguish and pain, but they can feel it. The objective of this study was to evaluate the postoperative analgesic efficiency of the use of 2mg.kg-1 epidural tramadol hydrochloride (GT), or 0,1mg.kg-1 epidural morphine sulfate (GM), in ewes submitted to cesarean section. After administration of the analgesia proposed via the epidural, it was expected 60 minutes to start the surgical procedure. The animals were evaluated before epidural administration. The animals were placed on the surgical table, in sternal decubitus, contained by limbs and eyelashes. After antisepsis, proximal paravertebral block with long spinal needle was performed in the T13-L1, L1-L2 and L2-L3 spaces, and 2 ml of lidocaine hydrochloride 2% without vasoconstrictor was deposited at each point. (T0), one hour after injection (T1), two (T2), three (T3), four (T4), six (T6), eight (T8), ten (T10), twelve (T12), sixteen T16), twenty (T20) and twenty-four hours (T24) post epidural administration. The surgical time was 112 ± 30 minutes. An adaptation of the UNESP Botucatu's One-Dimensional Scale for Post-Operative Pain Evaluation in Bovine was used. There was satisfactory analgesia up to 8 GT hours and 6 hours GM. There were no significant physiological changes. However, there was a greater reduction of ruminal and respiratory movements in GT. Scale adaptation was satisfactory in the evaluation of pain.