Eficacia analgésica de una dosis única de dexametasona perineural en el bloqueo ecoguiado del nervio femoral en cirugía de prótesis total de rodilla / Analgesic effect of a single-dose of perineural dexamethasone on ultrasound-guided femoral nerve block after total knee replacement

Introducción. La cirugía de prótesis de rodilla se caracteriza por tener un postoperatorio muy doloroso. El bloqueo del nervio femoral a dosis única ha demostrado proporcionar una analgesia similar a la epidural, con menos efectos secundarios pero limitado en el tiempo. Objetivo. Evaluar la eficacia de la analgesia proporcionada por la dexametasona utilizada a nivel perineural en el bloqueo del nervio femoral para cirugía de prótesis de rodilla, comparada con la aplicada a nivel intravenoso y con un grupo control. Material y métodos. Estudio prospectivo, aleatorizado, con enmascaramiento doble, controlado. Un total de 81 pacientes fueron aleatoriamente divididos en 3 grupos de estudio: 1) dexametasona 8mg i.v.; 2) dexametasona 8mg perineural, y 3)placebo. Todos los pacientes recibieron un bloqueo femoral con 20ml de ropivacaína al 0,5%. La variable principal fue la duración del bloqueo sensitivo-analgésico del nervio femoral. Como variables secundarias se midieron el dolor según EVA, la satisfacción del paciente y la incidencia de complicaciones. Resultados. La aleatorización fue efectiva. La duración de la analgesia fue significativamente mayor (p<0,0001) en el grupo dexametasona perineural (1.152,2 min; IC95%: 756,9-1.547,6) comparada con el grupo control (186 min; IC95%: 81,2-292) y el grupo dexametasona i.v. (159,4 min; IC95%: 109,8-209). El dolor postoperatorio, la incidencia de complicaciones y los efectos secundarios también fueron menores en este grupo. Conclusiones. La dexametasona prolonga el bloqueo sensitivo del nervio femoral realizado con ropivacaína, a la vez que proporciona una mejor analgesia con menos efectos secundarios (AU)

Introduction. Total knee replacement is usually a very painful procedure. A single-dose of femoral nerve block has been shown to provide similar analgesia to an epidural, with fewer side effects, but limited in time. Objective. To compare the analgesia provided by dexamethasone used at perineural level in the femoral nerve block after total knee replacement with the one used at intravenous level, and with that of a control group. Material and methods. A prospective, randomised, double-blind controlled trial was conducted on 81 patients randomly assigned to one of three groups: 1)IV dexamethasone (8mg); 2) perineural dexamethasone (8mg), and 3)placebo. All patients received 20ml of ropivacaine 0.5% for femoral nerve block. The primary outcome was the duration of the sensory-analgesic block of the femoral nerve block. The secondary outcomes included pain intensity measurements, patient satisfaction, and incidence of complications. Results. Randomisation was effective. Analgesia duration was significantly higher (P<.0001) in the perineural dexamethasone group (mean 1152.2 min, 95% confidence interval [95% CI]: 756.9-1547.6) in comparison with the control group (mean 186 min, 95%CI: 81.2-292) and dexamethasone IV group (mean 159.4min, 95%CI: 109.8-209). Postoperative pain, complications and side effects were also lower in this group. Conclusions. Dexamethasone prolongs sensory block of single dose of femoral nerve block using ropivacaine. It also provides better analgesia and patient satisfaction, with fewer side effects (AU)

Analgesic effect of a single-dose of perineural dexamethasone on ultrasound-guided femoral nerve block after total knee replacement. / Eficacia analgésica de una dosis única de dexametasona perineural en el bloqueo ecoguiado del nervio femoral en cirugía de prótesis total de rodilla.

INTRODUCTION: Total knee replacement is usually a very painful procedure. A single-dose of femoral nerve block has been shown to provide similar analgesia to an epidural, with fewer side effects, but limited in time. OBJECTIVE: To compare the analgesia provided by dexamethasone used at perineural level in the femoral nerve block after total knee replacement with the one used at intravenous level, and with that of a control group. MATERIAL AND METHODS: A prospective, randomised, double-blind controlled trial was conducted on 81 patients randomly assigned to one of three groups: 1)IV dexamethasone (8mg); 2)perineural dexamethasone (8mg), and 3)placebo. All patients received 20ml of ropivacaine 0.5% for femoral nerve block. The primary outcome was the duration of the sensory-analgesic block of the femoral nerve block. The secondary outcomes included pain intensity measurements, patient satisfaction, and incidence of complications. RESULTS: Randomisation was effective. Analgesia duration was significantly higher (P<.0001) in the perineural dexamethasone group (mean 1152.2min, 95% confidence interval [95% CI]: 756.9-1547.6) in comparison with the control group (mean 186min, 95%CI: 81.2-292) and dexamethasone IV group (mean 159.4min, 95%CI: 109.8-209). Postoperative pain, complications and side effects were also lower in this group. CONCLUSIONS: Dexamethasone prolongs sensory block of single dose of femoral nerve block using ropivacaine. It also provides better analgesia and patient satisfaction, with fewer side effects.