Dorsolumbar epidural analgesia in water buffalo: anaesthetic assessment and anatomical studies

ABSTRACT

Anesthesia of the flank region of ten native buffaloes was accomplished through the dorsolumber epidural technique by using two different doses [4ml and 5ml] from anesthetic mixture containing xylazine hydrochloride [2%] and lidocaine hydrochloride [2%]. Computed tomography and gross dissection were done for the thoraco-lumber region to show the special structures in this area. The results showed that, the anaesthetized area and the duration of analgesia in both sides of the flank region were wider and more prolonged at dose 5 ml than at 4 ml from the mixture. The CT showed that the epidural space at the lumbar region is enlarged and the widest part found at the third and fourth lumbar vertebrae. There is no inter-arcuate space between the last two thoracic vertebrae while the space was found between the last thoracic and the first lumbar vertebrae and continues between all lumbar vertebrae. Grossly, the last thoracic and first lumbar spinal nerve rootlets are nearly centered on the intervertebral discs between the last thoracic and the first lumbar vertebrae and between the first and the second lumbar vertebrae respectively. The second, the third, the fourth and the fifth lumbar spinal nerve rootlets are displaced cranially to extent, which the rootlets of the second and third lumbar spinal nerves are nearly located in the caudal portion of the canal of the second and third lumbar vertebrae respectively. Furthermore, the fourth lumbar spinal nerve rootlets are nearly located in the central part of the canal of the fourth lumbar vertebra, while the fifth lumbar spinal nerve rootlets appeared in the cranial portion of the canal of the fifth lumbar vertebra. The study illustrated that dorsolumber epidural anesthesia was easy to perform in buffaloes and consume low dose from anesthetic drug which save cost, time and effort. Moreover, adding of xylazine hydrochloride to the local anesthetic will promote its anesthetic properties in addition to the sedative effect needed in such conditions