Abstract
ABSTRACT
This study evaluated lidocaine/ropivacaine combination for epidural anesthesia by comparing the anesthetic indices and physiologic changes associated with epidural administration of lidocaine, ropivacaine and lidocaine- ropivacaine combination in goats. Using a prospective crossover study design, four male adult West African Dwarf goats received epidural injections of lidocaine (2 mg kg-1), ropivacaine (1 mg kg-1) and lidocaine- ropivacaine (1 mg kg-1; 0.5 mg kg-1) at two-week treatment intervals for drug wash out. Onset of analgesia was significantly longer (p ˂ 0.05) with lidocaine - ropivacaine (6.25 ± 2.22 minutes) than with ropivacaine (3.50 ±1.73 minutes) and lidocaine (3.00 ± 1.63 minutes). Duration of analgesia was significantly (p ˂ 0.05) longer with lidocaine - ropivacaine (168.50 ± 45.53 minutes) than with lidocaine (98.00 ± 26.65 minutes) but significantly shorter (p ˂ 0.05) than with ropivacaine (229.25 ± 33.54 minutes). Respective values for duration of recumbency and time to standing were intermediate with lidocaine - ropivacaine (137.00 ± 57.87; 200.50 ± 37.17minutes); longest with ropivacaine (167.00 ± 55.94; 281.25 ± 23.77 minutes) and shortest with lidocaine (80.75 ± 28.27; 130.50 ± 24.72 minutes) (p≤0.05). There were no significant differences (p ≥ 0.05) in physiological parameters temperature, heart and respiratory rates of goats following the three treatments. Epidural ropivacaine appears the best for long surgical procedures. The lidocaine-ropivacaine combination will be useful for procedures of moderate duration where a longer duration of analgesia than that produced by lidocaine alone is needed or where shorter recumbency period than possible with ropivacaine alone is desirable.

Key words: epidural anaesthesia, combination, goat, lidocaine, ropivacaine