Evaluation of anesthetic, locomotor, and sedative scores for lumbosacral epidural analgesia using bupivacaine and bupivacaine-dexmedetomidine in sheep.

BACKGROUND

Lumbosacral epidural analgesia is one of the most important techniques for sheep anesthesia and is frequently used for surgery in caudal body regions.

AIM: This study aimed to evaluate the antinociceptive, locomotor, and sedative effects of lumbosacral epidural injection of bupivacaine alone or in conjunction with dexmedetomidine in sheep.

METHODS

Nine clinically healthy mixed-breed sheep were used. Each sheep received either bupivacaine (BUP) alone or bupivacaine in combination with dexmedetomidine (BUP-DEX). The heart rate, heart rhythm, respiratory rate, and rectal temperature were monitored. Anesthetic onset, recumbency duration, and unassisted standing time were recorded. Analgesic, sedative, and locomotor scores were assessed using established numeric scales.

RESULTS

Analgesia onset was noted after 6.50 ± 2.75 minutes in the BUP group and after 4.33 ± 0.67 minutes in the BUP-DEX group. Sheep showed a tendency for recumbency in the BUP group at 3.33 ± 1.28 minutes after epidural injection and at 3.00 ± 0.68 minutes after epidural injection in the BUP-DEX group. Animals tended to stand earlier in the BUP group (199.83 ± 23.55 minutes) than in the BUP-DEX group (496.00 ± 82.97 minutes) (p = 0.014). Marked sedation was noted in the BUP-DEX group. Motor block was detected in both groups. The analgesic score was more intense and had a longer duration in BUP-DEX than in BUP. Minimal cardiorespiratory changes were observed in BUP-DEX.

CONCLUSION

Briefly using of bupivacaine-dexmedetomidine mixture for epidural anesthesia is an important technique in sheep subjected to long-term surgical operations in the tail, perineal, inguinal, hind limb, flank, and umbilical regions with sufficient sedation, long-term recumbency, and minimal side effects.