Clinical and haematological evaluation of subarachnoid ropivacaine, dexmedetomidine and their combinations with ketamine for tube cystostomy in urolithic buffalo calves

The study was conducted on 25 male buffalo calves of 3–4 months age, suffering from urolithiasis for 2–4 days. They were divided into five groups having five animals each. In group R, ropivacaine 0.45 mg/kg b.wt, in group RK ropivacaine and ketamine 0.225 mg/kg b.wt and 2 mg/kg b.wt, in group D dexmedetomidine 7.5 μg/kg b.wt, in group DK dexmedetomidine and ketamine 3.75 μg/kg b.wt and 2 mg/kg b.wt, and in group RDK ropivacaine, dexmedetomidine and ketamine 0.15 mg/kg b.wt, 2.5 μg/kg b.wt and 2 mg/kg b.wt were injected at lumbosacral subarachnoid space. The clinical examination revealed earliest onset of analgesia in group RK. However, duration of analgesia was almost same in all the groups. In animals of all the groups, complete analgesia of tail, perineum, inguinal region, thigh, digits, posterior flank and lower abdomen was seen. However, group RDK produced analgesia of greater extent and depth. Mild to moderate sedation was recorded in dexmedetomidine containing groups. Mild degree of salivation was recorded in group DK only. Recovery time was longest in group R (336 ± 51.66 min), while shortest in group D (128.80 ± 5.11 min). Haemoglobin, PCV and TLC values did not show significant change in any group. A significant neutrophilia and lymphocytopenia were recorded in groups R and D at 60 and 90 min intervals. The results of this study suggested that ropivacaine, dexmedetomidine and their combinations with ketamine produce only transient and minor changes in haematological parameters and produce good analgesia at lower abdomen and hence, considered safe for tube cystostomy in urolithic buffalo calves.