Comparative efficacy of lignocaine alone and in combination with Ketamine as epidural anaesthesia in cow calves

The present study was conducted to evaluate the clinico-physiological effects of epidural anaesthesia using lignocaine alone and in combination with ketamine in cow calves. Eight clinically healthy non-descript, stallfed male cow calves aged 7 to 8 months and weighing 55 to 65 kg were used in the study. Animals were divided in two groups of four animals each. In (group A) lignocaine @ 0.5mg/kg body wt. and in (group B) lignocaine @ 0.5mg/kg body wt with ketamine @ 2 mg/kg body wt. was administered at first inter coccygeal epidural space. Clinical observations such as, onset, depth of analgesia, area of desensitization, motor incoordination, salivation, heart-rate, respiration rate and rectal temperature O ( F) were recorded before and at 5, 10, 20, 30, 45, 60, 90, 120, 150,180 and 240 minutes after injection of drug(s). Ruminal movements were recorded at every 30 minutes after the injection of drug(s) upto complete recovery and 24 hours after the injection. The onset of analgesia in group B was significantly shorter as compared to group A. Group B animals induced deeper analgesia as compared to group A. In group A animals decrease in heart rate was recorded whereas in group B animals heart rate was increased. In group A, decrease in RR was observed.


Introduction
(group B) lignocaine @ 0.5mg/kg body wt with ketamine @ 2 mg/kg body wt. was administered at Lignocaine hydrochloride is an amide-linked first inter coccygeal epidural space.The volume of the local anaesthetic agent being used as 2% solution to drug injected was kept constant i.e. 6 ml in all the produce good surgical analgesia (1).Ketamine groups after reconstituting with distilled water.hydrochloride is a congener of phencyclidine and Clinical observations recorded included onset chemically designated as (2-{0-chlorophenyl}-2and depth of analgesia, area of desensitization, motor methylaminocyclohexanone). The commercial product incoordination and salivation before and at 5, 10, 20, is a 50:50 racemic mixture (2).The positive isomer is 30,45,60,90,120,150,180 and 240 minutes after more potent than negative isomer for analgesic injection.After epidural injection of drug(s), response properties (3).The analgesic properties of ketamine to pin-prick was recorded at every 15 second interval may be mediated via blockade of high affinity at thoracic, abdominal and inguinal region till the loss monoaminergic uptake sites and inhibition of reuptake of sensation.Depth of analgesia and area of desenof neurotransmitters (4).
sitization were recorded by observing response to The present study was conducted to evaluate the pinpricks at a particular region and were graded on a 0 clinico-physiological effects of epidural anaesthesia to 3 score scale viz.(0 score-no analgesia; 1 scoreusing lignocaine alone and in combination with mild analgesia; 2 score -moderate analgesia and 3 ketamine in cow calves.score-complete analgesia).

Materials and Methods
The motor incoordination was graded on a 0 to 3 score scale viz (0 score -no incoordination; 1 to 2 score Eight clinically healthy non-descript, stall-fed -animal standing and able to walk with little incoormale cow calves aged 7 to 8 months and weighing 55 dination; 2 to 3 score -animal standing but frequent to 65 kg were used in the study.Each animal was kept swaying of body and could walk with extreme off feed for 24 hrs and water was withheld for 12 hrs incoordination standing).Heart rate, respiratory rate prior to start of experiment.After routine preparations, O the animals were divided in two groups of 4 each.In and rectal temperature ( F) were recorded before and (group A) lignocaine @ 0.5mg/kg body wt. and in at 5,10,20,30,45,60,90,120,150,180  after injection of drug(s).Ruminal movements were However, salivation was completely absent at the end recorded at every 30 minutes from paralumbar fossa of observation.after the injection of drug(s) upto complete recovery In group A animals significant (P<0.05)decrease in heart rate was recorded between 20 to 60 min and 24 hours after the injection.Onset, persistency and cessation of salivation were also recorded.
interval whereas in group B animals heart rate was The mean and standard error of recorded values significantly (P<0.05)increased between 10 to 45 min were calculated.Data were analyzed by Completely interval.However, the values returned to near Randomized Design (CRD) as described by ( 5).
normalcy by 150 minutes.Increase in heart rate might be because ketamine produces its sympathomimetic

Results and Discussion
action primarily by direct stimulation of CNS The onset of analgesia in group B (5.65+1.86structures (3).In animals of group A, a significant min) was significantly (P<0.01)shorter as compared decrease (P<0.05) in RR was observed between 20 to to that of group A (10.73+2.82min).Lignocaine along 45 min.which returned to near pre-administration with ketamine (group B) induced deeper analgesia as level at the end of observation.Animals of group B, compared to lignocaine alone (group A).
showed a slight increase in RR up to 10 min interval, Depth of analgesia and area of desensitization at which became significant (P<0.05) between 30 to 60 tail, perineum and flank in group A animals was mild min interval.Then it decreased gradually and returned to moderate between 5 to 45 min which might be due to near base value at 180 min interval.The increase in to action of local anaesthetic drugs on spinal nerves RR might be due to the stimulatory action of ketamine that are blocked distal to the dural sheaths after leaving on the respiratory center.(10) reported that tachypnoea the intervertebral foramina, producing a multiple occurs due to a residual effect of ketamine, as ketamine paravertebral block as reported by ( 6) in buffalo activates certain subcortical areas of the CNS.In calves.Group B animals showed complete analgesia animals of both the groups a non significant decrease of tail, perineum, inguinal and flank region between 10 in RT was observed upto 45 min which became to 60 min and mild to moderate analgesia of thorax, significant (P<0.05) between 60 to 150 min in group A ventral abdomen and digits which might be due to the and 60 to 180 min in group B. This might be due to the fact that ketamine is a potent non-competitive antagonist reduced basal metabolic rate, muscle activities and of NMDA receptors, which are involved in the transdepression of thermoregulatory centre.Ruminal mission and modulation of nociceptive information at movements showed a non significant decrease between the spinal cord level (7).Ataxia and motor in 30 to 60 min in both the groups.The values returned to coordination was maximum (1 to 2 score scales: near preadministration level by 24 hrs.animal standing and able to walk with little incoor-

Table - 1. Score of analgesia of Tail, Perineum, Flank, Inguinal, Hind limb, Thorax and Ventral abdomen after different treatments at various time intervals in different groups.
and 240 minutes