Anestesia regional guiada por ultrasonido en territorio del nervio pudendo / Regional anesthesia guided by ultrasound in the pudendal nerve territory

Abstract Introduction: Pudendal nerve blocks have a wide range of clinical applications for the management of acute post-operative pain in urologic, gynecological surgery, in coloproctology, as well as in pain medicine for differential diagnosis, and for the management of pudendal neuropathies. However, despite its benefits it is infrequently used. Objective: To perform a detailed description of the most recent ultrasound-guided techniques with the aim of encouraging safe and reproducible learning. Materials and methods: We have performed a broad, non-systematic review of the literature through Medline, Embase and Science Direct between 1985 and 2016, to evaluate the most relevant articles, using the following key words: pudendal nerve anatomy, pudendal nerve, pudendal nerve blocks, pudendal nerve ultrasound, pudendal neuralgia, nerve entrapment, chronic pain, Alcock canal, and pelvic pain. The search was limited to articles published in Spanish, English and French. Results: Recent descriptions were found of a large number of anatomic variants, which are described in detail and shown in graphic documents in order to facilitate the sonoanatomic correlation of nerve location as a guide for the performance of the pudendal nerve block through the different approaches. Conclusions: The deep and detailed knowledge of the anatomy of the pudendal nerve and its variations is essential for the realization of Regional Anesthesia techniques guided by images. These promising techniques should continue to be evaluated with clinical studies.

Resumen Introducción: Los bloqueos del nervio pudendo poseen un amplio rango de utilidades clínicas en el manejo agudo de dolor POP en cirugía urológica, ginecológica, en coloproctología, así como en medicina del dolor en diagnóstico diferencial y manejo de las neuropatías del nervio pudendo. Sin embargo, su aplicación es relativamente infrecuente a pesar de los beneficios. Objetivo: Realizar una descripción detallada de las técnicas más recientes guiadas por ultra-sonografía con el objeto de motivar su aprendizaje de una manera segura y reproducible. Materiales y métodos: Se realizó una revisión amplia, no sistemática de la literatura a través de Medline, Embase y Science Direct desde 1985 hasta 2016, evaluando los artículos más relevantes, utilizando las palabras clave: anatomía del nervio pudendo, nervio pudendo, bloqueos del nervio pudendo, ultrasonido del nervio pudendo, neuralgia del pudendo, atrapamiento nervioso, dolor crónico, canal de Alcock y dolor pélvico. La búsqueda se limitó a artículos publicados en español, inglés y francés. Resultados: Se encontraron recientes descripciones de una gran cantidad de variantes anatómicas, que se describen en detalle y muestran en documentos gráficos con el propósito de facilitar la correlación sonoanatómica de la localización del nervio como guía para la realización de bloqueos de nervio pudendo a través de los diferentes abordajes. Conclusiones: El conocimiento profundo y detallado de la anatomía del nervio pudendo y sus variaciones es esencial para la realización de técnicas de anestesia regional guiada por imágenes. Estas técnicas promisorias deben continuar evaluándose con estudios clínicos.

Esmolol versus ketamine-remifentanil combination for early postoperative analgesia after laparoscopic cholecystectomy: a randomized controlled trial.

PURPOSE: Controversy surrounds the optimal technique to moderate pain after laparoscopic cholecystectomy (LC). Opioid analgesics, sympatholytic drugs, and adjuvants, such as ketamine, have all been used. We compared esmolol with a combination of remifentanil plus ketamine in patients undergoing LC to determine the impact of these drugs on morphine requirements and pain control. METHODS: Sixty American Society of Anesthesiologists physical status I-II patients undergoing LC and anesthetized with sevoflurane were randomized to one of two groups. Group E patients received a bolus of esmolol 0.5 mg·kg(-1) iv at induction followed by an infusion of 5-15 µg·kg(-1)·min(-1), and Group R-K patients received a bolus of ketamine 0.5 mg·kg(-1) iv and remifentanil 0.5 µg·kg(-1) iv at induction followed by a remifentanil infusion titrated over a range of 0.1-0.5 µg·kg(-1)·min(-1). All patients received paracetamol, dexketoprofen, and levobupivacaine via infiltration of laparoscopic port sites. After surgery, a predetermined bolus of morphine was administered according to a verbal numerical rating scale (VNRS) for pain intensity. The primary outcome of interest was postoperative morphine requirement. RESULTS: Median consumption of morphine was higher in Group R-K than in Group E (5 mg [4-6] vs 0 mg [0-2], respectively; P < 0.001). In the postanesthesia care unit, patients in Group R-K had higher pain scores than patients in Group E (difference in maximum VNRS, -11; 95% confidence interval (CI), -19 to -3). The concentration of sevoflurane to maintain a bispectral index~40 was higher in Group E than in Group R-K (between-group difference 0.3%; 95% CI, 0.15 to 0.40). The incidence of postoperative nausea and vomiting was similar between the two groups. CONCLUSION: Intraoperative esmolol infusion reduces morphine requirements and provides more effective analgesia compared with a combination of remifentanil-ketamine given by infusion in patients undergoing LC.