Epidural anesthesia in Egyptian water buffalo (Bubalus bubalis): a comparison of lidocaine, xylazine and a combination of lidocaine and xylazine

Objective To evaluate and compare the analgesic effects of a combination of lidocaine and xylazine to lidocaine or xylazine administered alone for epidural anesthesia in Egyptian water buffalo (Bubalus bubalis). Study design Prospective, randomized, 'blinded', crossover experimental study. Animals A total of 12 female Egyptian water buffalo. Methods Buffalo were randomly assigned to one of three epidural treatments administered through the sacrococcygeal joint: a local anesthetic (2% lidocaine, 0.22 mg kg(-1)), an alpha-2-adrenergic agonist (xylazine, 0.1 mg kg(-1)) or a combination of both drugs in a rossover fashion with a 14 day washout period. The total volume of each treatment was fixed at 7.0 mL by adding 0.9% NaCl. Onset, maximal effect, and duration of epidural anesthesia were recorded. Results Caudal epidural anesthesia was easily performed, and all three treatments produced local anesthesia of the tail and perineal structures of standing buffalo. Onset of epidural anesthesia was faster (p < 0.05) with lidocaine (3.4 +/- 0.9 minutes) than with xylazine (9.1 +/- 1.1 minutes) or lidocaine-xylazine (6.4 +/- 1.1 minutes). The maximal effect of epidural anesthesia was reached faster (p < 0.05) with lidocaine (5.9 +/- 0.64 minutes) than xylazine (14.4 +/- 1.1 minutes) or lidocaine-xylazine (12.9 +/- 0.64 minutes). The duration of epidural anesthesia was longer (p < 0.05) with lidocaine- xylazine (145.8 +/- 3.3 minutes) than either lidocaine (118.4 +/- 2.7 minutes) or xylazine (102.1 +/- 3.7 minutes) administered alone. None of the treatments produced ataxia. Conclusions and clinical relevance Caudal epidural anesthesia was easily performed in Egyptian water buffalo by administering a local anesthetic, an alpha-2-adrenergic agonist or a combination of both drugs through the sacrococcygeal joint. Administering a combination of lidocaine and xylazine provided a longer duration of anesthesia than either drug used alone. Epidural xylazine provided a useful level of systemic sedation without ataxia.