Comparative study of epidural anesthesia in dogs by weight or occipito-coccygeal distance

Abstract

RESUMOThe effects of volume on lumbosacral epidural block in dogs were evaluated using two different doses of 2% lidocaine. Ten adult dogs, without defined breed, were subjected to two different anesthetic protocols. In the first, the local anesthetic was calculated based on the body weight (GP), wherein 1.0 mL of local anesthetic was used for each 3.5 kg; in the second protocol, the dose was stipulated according to the occipito-coccygeal (DG) distance with 1.5mL of local anesthetic for every 10 cm of distance. The available time, recovery period, extent of block, and rectal temperature were measured. After the analysis of the results, it was possible to verify that there was an increase in the time in GD when compared with GP, due to the greater volume administered in that group. The recovery period remained similar in both groups, despite the use of different doses. Regarding the extent of blockade, there was an increase in GD in relation to GP due to the increase of the local anesthetic dose. On the other hand, the rectal temperature presented a difference between the groups, remaining lower and below the reference values for the species in GD compared with GP at all moments analyzed, possibly due to a sympathetic action triggered by the cranial extension of the epidural block. It could be concluded that when a longer time and a more cranial blockade of epidural anesthesia are desired, the anesthesia volume should be based on the occipito-coccygeal distance, however, observing the rectal temperature.Key words: lidocaine; volume; timing; recovery time; rectal temperature. Gisele Martins de Paula Estudo comparativo da anestesia epidural em cães por peso ou distância ocipto-coccígeaAvaliaram-se os efeitos do volume no bloqueio epidural lombossacro em cães utilizando-se duas doses diferentes de lidocaína a 2%. Foram utilizados dez cães adultos, SRD submetidos: No primeiro protocolo, o anestésico local foi calculado com base no peso corporal (GP) e no segundo protocolo a dose foi estipulada de acordo com a distância ocipto-coccígea (GD). Sendo os mesmos animais submetidos aos dois protocolos anestésicos, com intervalo de dez dias. Mensurou-se o tempo hábil, o período de recuperação, a extensão do bloqueio e a temperatura retal. Após a análise dos resultados foi possível constatar que houve acréscimo no tempo hábil em GD quando comparado a GP, devido ao maior volume administrado em tal grupo. O período de recuperação se manteve semelhante em ambos os grupos, apesar do uso de doses diferentes. Com relação à extensão do bloqueio, houve um aumento em GD quando comparado a GP devido ao aumento da dose de anestésico local. Já a temperatura retal apresentou diferença entre os grupos, mantendose menor e abaixo dos valores de referência para a espécie, em GD na comparação com GP em todos os momentos analisados possivelmente devido a uma ação simpática desencadeada pela extensão cranial do bloqueio epidural. Pode se concluir que quando se dejesa um maior tempo hábil e um bloqueio mais cranial de anestesia epidural...

Analgesic and Sedative Effects of Epidural Lidocaine-Xylazine in Elective Bilateral Laparoscopic Ovariectomy in Standing Mule Mares

“…It is important to highlight that the body length of the two mules that received supplementary ovarian local analgesia was longer than the others, which may have impeded the epidural analgesics from reaching the sacral spinal nerve 3 (S3). This hypothesis could lead to conclude that further comparative studies are needed to determine whether the dose of agents administered via the epidural route according to the desired effect should take into account the body weight of the animal or the extension of the vertebral column, as it has been reported in small animals [ 42 , 43 , 44 ]. Therefore, operators should pay attention more to that physical parameter rather than to the effective weight in mules, which is the main parameter we normally consider when preparing the dose and volume for epidural analgesic drugs combination.…”

Epidural Volume of Injectate Using a Dose Regimen Based on Occipito-Coccygeal Spinal Length (OCL): Randomized Clinical Study Comparing Different Ropivacaine Concentrations, with or without Morphine, in Bitches Undergoing Total Unilateral Mastectomy

“…When performing lumbosacral epidural anaesthesia, two methods are commonly used to determine the volume of injectate: one based on body weight, and another based on the vertebral column length [ 18 , 19 ]. Interestingly, controversies regarding the most appropriate method are still ongoing [ 20 , 21 ]. In case the volume is calculated using a dose regimen based on the vertebral column length, the volume is obtained either by using a fixed volume per cm of vertebral column length, as 1 mL per 10 cm −1 of occipito-coccygeal length (OCL) [ 12 , 21 ] or by using a nomogram that allows adjusting the volume of injectate as a function of the desired percentage of OCL to desensitize [ 22 ].…”