Bloqueo del nervio ciático poplíteo ecoguiado en urgencias en un paciente pediátrico con dolor severo producido por una picadura de escorpión / Ultrasound-guided sciatic popliteal block performed at the Emergency Department in a patient with a scorpion bite and severe pain

Presentamos el caso de un paciente pediátrico que acudió a urgencias con dolor severo en la extremidad inferior derecha causado por la picadura de un escorpión. Ante la ausencia de respuesta a los analgésicos administrados se optó por realizar un bloqueo poplíteo ecoguiado, lo que consiguió una analgesia completa y permitió el manejo ambulatorio del paciente, sin referir efectos adversos. Las familias de escorpiones presentes en nuestro país no suponen un riesgo vital para el ser humano, pero su picadura produce una reacción local con dolor autolimitado a unas 24-48h que puede ser severo. El manejo prioritario es realizar una correcta analgesia. Las técnicas anestésicas regionales son de utilidad para el control del dolor agudo y pueden representar una colaboración eficaz entre los servicios de anestesiología y urgencias.(AU)

We report the case of a paediatric patient who presented at the Emergency Department with severe pain in the right lower extremity caused by a scorpion sting. Analgesics were ineffective, so we decided to perform an ultrasound-guided popliteal block. This, which achieved complete analgesia and allowed the patient to be followed up in the outpatient department, with no adverse effects. The sting of the species of scorpion found in Spain is not dangerous to human life; however, it causes self-limiting localised pain that lasts for 24-48hours, and can be severe. The first-line treatment is effective analgesia. Regional anaesthesia techniques are useful in the control of acute pain, and are an example of effective collaboration between the Anaesthesiology and Emergency services.(AU)

Ultrasound-guided sciatic popliteal block performed at the Emergency Department in a patient with a scorpion bite and severe pain.

We report the case of a paediatric patient who presented at the Emergency Department with severe pain in the right lower extremity caused by a scorpion sting. Analgesics were ineffective, so we decided to perform an ultrasound-guided popliteal block, which provided complete analgesia and allowed the patient to be followed up in the outpatient department, with no adverse effects. The sting of the species of scorpion found in Spain is not dangerous to human life; however, it causes self-limiting localised pain that lasts for 24-48h, and can be severe. The first-line treatment is effective analgesia. Regional anaesthesia techniques are useful in the control of acute pain, and are an example of effective collaboration between the Anaesthesiology and Emergency services.

Influencia de la posición en la visualización con ultrasonido del nervio ciático en la fosa poplítea por médicos en formación / Patient positioning and ultrasound visualization of the sciatic nerve in the fossa by anesthesia residents

OBJECTIVE: Evaluate the effect of the patients' position in obtaining a good quality image of the sciatic nerve at the popliteal fossa by anesthesiology trainees. METHODS: First and 2nd year residents of our anesthesiology program scanned de right popliteal fossa of a unique subject. The subject laid in 3 different positions (supine, lateral and prone). Before the scanning, residents reviewed a video showing basic ultrasound probe management and images of the sciatic nerve at the popliteal fossa. Time elapsed upon receiving the ultrasound probe and obtaining a good quality image was measured (at least 70% counter definition and 3 clearly identified structures within the nerve). An evaluator (blinded to the subject position) determined during real time observation the quality of the image. Residents completed a questionnaire regarding the experience lived. RESULTS AND CONCLUSIONS: 26 residents completed the study. There were no statistical differences in the overall time needed by residents to obtain a good quality image in the 3 different positions. Although 96% felt that position influenced the ability to obtain good image. From this experience residents would prefer to do an US guided popliteal block on the prone position.

OBJETIVOS: Evaluar la influencia de la posición del paciente en la obtención de una imagen de calidad del nervio ciático a nivel poplíteo por médicos en formación del programa de anestesiología. METODOLOGÍA: Médicos en formación del programa de Anestesiología examinarán desde la cara posterior la fosa poplítea derecha de un único sujeto en tres posiciones diferentes. Previamente serán expuestos a un video del uso del ecógrafo y de imágenes del nervio ciático a nivel poplíteo. Se consignará el tiempo desde que reciben el transductor hasta obtener imagen del nervio ciático con al menos 70% de definición de contorno y más de 3 estructuras visibles en su interior. Un investigador en tiempo real, ciego a la posición del modelo, decidirá si la imagen cumple los criterios. Finalmente completan una encuesta sobre apreciación subjetiva de la experiencia. RESULTADOS Y CONCLUSIONES: Se evaluaron 26 residentes en total. No hubo deferencias en el tiempo que necesitaron para obtener una imagen de buena calidad del nervio ciático a nivel de la fosa poplítea en las distintas posiciones.

Ultrasound guided injection inside the common sheath of the sciatic nerve at division level has a higher success rate than an injection outside the sheath.

BACKGROUND AND OBJECTIVE: The recommendations for the level of injection and ideal placement of the needle tip required for successful ultrasound-guided sciatic popliteal block vary among authors. A hypothesis was made that, when the local anesthetic is injected at the division of the sciatic nerve within the common connective tissue sheath, the block has a higher success rate than an injection outside the sheath. METHODS: Thirty-four patients scheduled for hallux valgus repair surgery were randomized to receive either a sub-sheath block (n=16) or a peri-sheath block (n=18) at the level of the division of the sciatic nerve at the popliteal fossa. For the sub-sheath block, the needle was advanced out of plane until the tip was positioned between the tibial and peroneal nerves, and local anesthetic was then injected without moving the needle. For the peri-sheath block, the needle was advanced out of plane both sides of the sciatic nerve, to surround the sheath. Mepivacaine 1.5% and levobupivacaine 0.5% 30mL were used in both groups. The progression of motor and sensory block was assessed at 5min intervals. Duration of block was recorded. RESULTS: Adequate surgical block was achieved in all patients in the subsheath group (100%) compared to 12 patients (67%) in the peri-sheath group at 30min. Sensory block was achieved faster in the subsheath than peri-sheath (9.1±7.4min vs. 19.0±4.0; p<.001). CONCLUSIONS: Our study suggests that for successful sciatic popliteal block in less than 30min, local anesthetic should be injected within the sheath.