A comparison of epidural anaesthesia with lignocaine, bupivacaine and a lignocaine-bupivacaine mixture in cats

Abstract

A mixture of 2% lignocaine (LIG) and 0.5% bupivacaine (BUP), at respective dose rates of 2 mg/kg and 0.5 mg/kg (LIG-BUP), was compared to LIG (4 mg/kg) and BUP (1 mg/kg) for lumbosacral epidural anaesthesia in 5 sedated cats. Each cat received all 3 treatment regimens at 1-week intervals. The cats were premedicated with an intramuscular injection of atropine sulphate (0.04 mg/kg) and ketamine hydrochloride (10 mg/kg). Onset and duration of analgesia, and time to walking were determined. Associated changes in heart rate (HR), respiratory frequency (ƒR) and rectal temperature (RT) were recorded. Onset of analgesia with epidurally administered LIG-BUP (4.5 ± 0.7 min), LIG (3.9 ± 1.0 min) and BUP (5.0 ± 1.0 min) was similar. Duration of analgesia with LIG-BUP (49.4 ± 4.5 min) was significantly (P < 0.05) longer than with LIG (40.2 ± 1.0 min) but shorter than with BUP (79.4 ± 6.3 min). There were no significant differences in times to standing with LIG-BUP (26.3 ± 6.4 min), LIG (20.4 ± 4.7 min) and BUP (22.6 ± 10.3 min). Minimal changes were observed in HR, ƒR and RT. In conclusion, duration of analgesia produced by LIG-BUP was shorter compared with BUP but longer compared with LIG. Neither LIG nor LIG-BUP has any advantage over epidural BUP in terms of onset of analgesia, time to standing and physiological responses. Therefore, lumbosacral epidural administration of BUP appears to be the best choice for a long surgical procedure lasting more than 1 hour when compared with either LIG or LIG-BUP.

Evaluation of Oral Robenacoxib for the Treatment of Postoperative Pain and Inflammation in Cats: Results of a Randomized Clinical Trial

“…Once fully anesthetized, the cats received forelimb 4-point regional nerve blocks under aseptic conditions to achieve local anesthesia of the median nerve, palmar branch of the ulnar nerve, and the dorsal digital nerves I to V. The local anesthetic used was 0.5% bupivacaine with the total dosage for both paws not exceeding 5.0 mg/kg [9]. Bupivacaine was selected for its relatively long duration of action, reported to be over 1 hour in cats [10]. …”

Epidural levobupivacaine alone or combined with different morphine doses in bitches under continuous propofol infusion

“…Similar findings have been reported after administration of morphine (0.1mg kg -1 ) and sodium chloride (0.9% NaCl) epidurally in bitches resulting in cardiovascular stability (Pereira and Marques, 2009). Lawal and Adetunji (2009) have compared the effects of epidural bupivacaine (1mg kg -1 ), lidocaine (4mg kg -1 ) or lidocaine (0.5mg kg -1 ) combined with bupivacaine (0.5mg kg -1 ) in cats. No significant cardiac changes were observed, similarly to the levobupivacaine alone.…”

An Update on Drugs Used for Lumbosacral Epidural Anesthesia and Analgesia in Dogs

“…Bupivacaine is another amide type local anesthetic with a prolonged duration of effect compared with lidocaine (56) and may induce ventricular arrhythmias and cardiotoxicity at lower doses than lidocaine (57) but this is usually not a concern when doses and concentrations stated in this review are followed. At clinically used doses, epidural bupivacaine has limited effects on ventilation and oxygenation (24).…”