RESEARCH PAPER: Segmental dorsolumbar epidural analgesia via the caudal approach using multiple port catheters with ketamine or lidocaine or in combination in cattle

ObjectiveTo determine the analgesic and systemic effects of epidural administration of ketamine, lidocaine or a combination of ketamine/lidocaine in standing cattle.Study designProspective, randomized, experimental trial.AnimalsSix healthy male cattle weighing between 335 and 373 kg.MethodsThe animals received 0.5 mg kg^?1 of ketamine (K), 0.2 mg kg^?1 of 2% lidocaine (L) or 0.25 mg kg^?1 ketamine plus 0.1 mg kg^?1 lidocaine (KL). All the drugs were injected into the dorsolumbar epidural space via a caudal approach through a non‐styletted multiple‐port catheter. Each animal received each treatment at random. Evaluations of analgesia, sedation, ataxia, heart rate, arterial pressure, respiratory rate, skin temperature and rectal temperature were obtained at 0 (basal), 5, 10, 15, 30, 45, 60, 75, 90 minutes after epidural injection, and then at 30‐minute intervals until loss of analgesia occurred. Skin temperature was taken at these intervals up to 60 minutes. All the animals received a standard noxious stimulus; a 4‐point scale was used to score the response. A second scale was used to score ataxia and a third for sedation.ResultsThe duration of analgesia in the upper and lower flanks in cattle was 140 ± 15, 50 ± 14 and 80 ± 22 minutes (mean ± SD) after dorsolumbar epidural KL, K or L, respectively. The cardiovascular changes were within acceptable limits in these clinically healthy cattle.ConclusionsDorsolumbar epidural administration of KL to cattle resulted in longer duration of analgesia of the upper and lower flanks in standing conscious cattle, than the administration of K or L alone.Clinical relevanceFurther research is necessary to determine whether this combination using this technique provides sufficient analgesia for flank surgery in standing cattle.     

Lignocaine versus bupivacaine for flank anaesthesia using multiport catheters via a caudal epidural approach in cattle

Objective To determine the anaesthetic and systemic effects of dorsolumbar epidural anaesthesia using non-stylet multiport catheters via the caudal approach to administer hypertonic 5% lignocaine (HL) or hypertonic 0.5% bupivacaine (HB) to the flank in standing cattle. Materials and methods Six healthy adult cattle weighing 310–455 kg received 0.2 mg/kg HL or 0.025 mg/kg of HB; control animals received 0.9% saline solution. All drugs were injected into the dorsolumbar epidural space via a caudal approach through a non-stylet multiport catheter. Each animal received each treatment at random. Evaluations of anaesthesia, ataxia, heart rate, arterial pressures, respiratory rate and rectal temperature were obtained at 0 (basal), 5, 10, 15, 30, 45, 60, 75, and 90 min after epidural injection and then at 30-min intervals until loss of anaesthesia. All animals received a standard noxious stimulus and a 4-point scale was used to score the response. A second scale was used to score ataxia. Results The duration of anaesthesia in the upper and lower flanks in cattle was 68 ± 12 and 110 ± 15 min (mean ± SD) after dorsolumbar epidural HL or HB, respectively. Both hypertonic local anaesthetics produced a mild ataxia. The systemic changes were within acceptable limits in these clinically healthy cattle. Conclusion In standing cattle the dorsolumbar epidural injection of hypertonic lignocaine provided faster onset of anaesthesia and fewer cardiovascular effects, but had a shorter duration of anaesthesia than hypertonic bupivacaine.     

Successful introduction of modified dorsolumbar epidural anesthesia in a bovine referral center

This study describes the successful use of modified dorsolumbar epidural anesthesia with a fixed volume of anesthetic in a bovine referral center. Among the 130 Holstein cattle scheduled for flank surgery, 90 cattle received a mixed anesthetic consisting of 1 ml of xylazine hydrochloride and 3 ml of lidocaine hydrochloride by modified dorsolumbar epidural anesthesia. Eighteen cattle with dehydration and/or lameness received a mixed anesthetic containing 0.5 ml of xylazine and 3 ml of lidocaine. Infiltration anesthesia was performed in 22 cattle whose epidural space could not be reached in order to perform the flank surgery. The surgeries began about 12 min after the administration of the anesthetic and lasted for about 36 min. The modified method using a fixed volume of anesthetic was successfully introduced and effectively used in a bovine referral center. This modified method will allow veterinarians to save time and effort, thus lowering the cost of each surgery.     

Eliminating the effect of epidural fat during dorsolumbar epidural analgesia in cattle

Objective To compare the distribution of new methylene blue (NMB) solution injected into either the subperiosteal space or under the epidural fat at the first and second lumbar vertebral interspace in cattle. Study design Prospective experimental study. Sample population Nine nonpregnant cows. Methods Needles were advanced towards the first interlumbar epidural space using a dorsal mid‐line approach. Upon confirmation of successful penetration of the ligamentum flavum, group 1 received 5 mL of 0.12% NMB in 0.9% saline. In group 2, the needle was slowly advanced a further 7–10 mm to ensure injection under the epidural fat; the same dose was injected. The extent of cranial and caudal migration of dye, as indicated by staining of epidural fat and the dura mater was measured. Results In group 1 (n = 4), NMB solution migrated only between the periosteum and the epidural fat. There was unilateral distribution in two cows. In contrast, there was no difference between left‐ and right‐sided distribution in group 2 (n = 5), and the NMB solution migrated only between epidural fat and the dura mater. Although the dura mater was not penetrated in any animal of group 2, the dorsal roots were slightly stained and the overlying dura mater was heavily stained in these animals. Conclusions and clinical relevance Variation in distribution of local anaesthetic solution can probably be overcome by deeper needle penetration of the epidural fat.     

Practical tips for modified dorsolumbar epidural anesthesia in cattle

Segmental dorsolumbar epidural anesthesia has been considered difficult to perform. The purpose of this study was to determine whether or not it is difficult for beginners to learn how to do modified dorsolumbar epidural anesthesia of cattle. Thirty cattle were divided into two groups, young (n = 8) and adult (n = 22), according to their age and body weight, and 0.12% new methylene blue (NMB) was injected into the first interlumbar (L1-L2) epidural space by four fifth-year veterinary school students who had never performed this method. After a 1 hour lecture on the modified dorsolumbar epidural anesthesia procedure which included basic anatomy and skills, each student successfully performed the procedure. In the young group, the NMB solution was distributed between the periosteum and the epidural fat (BPF) in one half and between the epidural fat and the dura mater (BFD) in the other half of the cattle. In about 60% (13/22) of the adult group, the NMB solution distributed as BFD type. This study showed that the modified dorsolumbar epidural anesthesia procedure is easy for beginners to perform if they overcome their fear about the deeper insertion of the epidural needle with basic anatomical knowledge and a little experience.