Outpatient management of acute uncomplicated appendicitis after laparoscopic appendectomy: a randomized controlled trial.

OBJECTIVE: To confirm the safety and efficacy of outpatient management of laparoscopic appendectomy, with an enhanced recovery after surgery (ERAS) protocol, in adult patients with uncomplicated acute appendicitis. Outpatient laparoscopic appendectomy is feasible and secure in selected patients in observational studies. The benefits include reduced length of stay (LOS) and postoperative complications. This is the first randomized controlled trial of outpatient management following ERAS protocol. METHODS: Patients admitted from the emergency department with acute appendicitis were randomized into one of two groups: standard care within the hospital (HG) or the outpatient group (OG). An ERAS protocol was followed for both groups. Patients in the HG were admitted to the surgical ward. Patients in the OG were referred to the day-surgery unit. The primary endpoint was the length of stay. RESULTS: Ninety-seven patients were included: 49 in the OG and 48 in the HG. LOS was significantly shorter in the OG (mean 8.82 h) than in the HG (mean 43.53 h), p < 0.001. There was no difference in readmission rates (p = 0.320); we observed only one readmission in the OG. No further emergency consultations or complications were observed. The cost saving was $516.52/patient as a result of the intervention. CONCLUSION: Outpatient management of appendectomy is safe and feasible procedure in selected patients. This approach could become the standard of care for patients with uncomplicated appendicitis, showing fewer complications, lower LOS and cost. TRIAL REGISTRATION: Registration: www. CLINICALTRIALS: gov (NCT05401188) Clinical Trial ID: NCT05401188.

Clinical implications of diabetes mellitus in patients with acute coronary syndrome: Prognostic role and use of new P2Y12 receptor inhibitors.

AIMS: We investigated the impact of diabetes mellitus (DM) in acute coronary syndrome (ACS) patients, and the 2-year prognosis based on antiplatelet therapy. METHODS: This is a prospective and multicenter registry including hospitalized ACS patients. Clinical management and antiplatelet therapy at discharge were recorded. Bleeding events, all-cause mortality and major adverse cardiovascular events (MACEs) were recorded during 2-years and compared according to DM and the P2Y12 receptor inhibitor. RESULTS: From 1717 ACS patients, 653 (38%) had DM. Diabetic patients were older, more commonly females, with higher prevalence of comorbidities and more conservative management. After excluding antiplatelet monotherapy or oral anticoagulation, clopidogrel was prescribed in 59.6% of DM patients. Cox regression analysis showed that DM was an independent risk factor for MACE (aHR 1.39, 95% CI 1.05-1.83). The use of clopidogrel instead of ticagrelor/prasugrel was also independently associated with MACE (aHR 1.71, 95% CI 1.11-2.63), and all-cause mortality (aHR 2.47, 95% CI 1.23-4.96) in diabetic patients (log-rank p-values < 0.001). CONCLUSIONS: In ACS patients, DM was associated with higher risk of MACE. In such patients, the use of ticagrelor/prasugrel reduced MACE and mortality compared to clopidogrel. Novel P2Y12 receptor inhibitors might be used as the first therapeutic choice in these high-risk patients.

Importancia de los hallazgos de la resonancia magnética cardiaca en el diagnóstico de la miocardiopatía arritmogénica del ventrículo izquierdo / Importance of cardiac magnetic resonance findings in the diagnosis of left dominant arrythmogenic cardiomyopathy

INTRODUCCIÓN Y OBJETIVOS: Recientemente, la miocardiopatía arritmogénica del ventrículo izquierdo (MCAVI) ha sido reconocida como parte del espectro de la miocardiopatía arritmogénica. Se caracteriza por el reemplazo fibroadiposo de la pared de dicho ventrículo. Se describen las formas de presentación clínica más frecuentes, hallazgos de imagen y eventos en el seguimiento, destacando la importancia de la resonancia magnética cardiaca (RMC). MÉTODOS: Registro prospectivo de pacientes con hallazgos compatibles con MCAVI. Se realizó análisis de imagen de RMC y seguimiento clínico. El objetivo primario fue la aparición de eventos cardiovasculares adversos mayores (MACE) durante el seguimiento, definidos como muerte súbita cardiaca, arritmias ventriculares sostenidas y trasplante cardiaco. RESULTADOS: Se incluyeron 74 pacientes consecutivos (edad media 48,6 años, 50 varones [67,6%]). Las indicaciones más frecuentes para la RMC fueron dolor torácico con coronariografía normal, arritmias ventriculares y sospecha de miocardiopatías. Los principales hallazgos de RMC fueron: realce tardío meso-subepicárdico (91,9%), infiltración grasa subepicárdica (83,8%) y anomalías segmentarias de la contractilidad del ventrículo izquierdo (47,9%). En un seguimiento medio de 3,74 años, 24 pacientes (32,4%) presentaron un MACE (muerte súbita cardiaca 8,1%, arritmias ventriculares sostenidas 21,6% y trasplante cardiaco 4,1%). La presencia en RMC de realce tardío grave, predice independientemente la aparición de MACE, además del hecho de ser varón y practicar deporte. CONCLUSIONES: La RMC es una herramienta clave para diagnosticar la MCAVI. La infiltración grasa subepicárdica y el realce tardío meso-subepicárdico son hallazgos característicos. El pronóstico de esta población es pobre con una alta incidencia de muerte súbita cardiaca y arritmias ventriculares

INTRODUCTION AND OBJECTIVES: Left dominant arrhythmogenic cardiomyopathy (LDAC) has recently been recognized as falling on the spectrum of arrhythmogenic cardiomyopathy. It is characterized by fibroadipose replacement of the left ventricle. The aim of this study was to describe the most frequent forms of clinical presentation of LDAC, imaging findings, and events at follow-up, highlighting the importance of cardiac magnetic resonance (CMR). METHODS: Prospective registry of patients with findings compatible with LDAC. CMR image analysis and clinical follow-up was performed. The primary endpoint was the appearance of major adverse cardiovascular events (MACE) during follow-up, defined as sudden cardiac death, sustained ventricular arrhythmias, and heart transplant. RESULTS: We included 74 consecutive patients (mean age, 48.6 years; 50 men [67.6%]). The most frequent CMR indications were chest pain with normal coronary angiography, ventricular arrhythmias, and suspicion of cardiomyopathies. The main CMR findings were midwall and/or subepicardial pattern of late gadolinium enhancement (91.9%), fatty epicardial infiltration (83.8%), and left ventricle segmental contractility abnormalities (47.9%). At a mean follow-up of 3.74 years, 24 patients (32.4%) had a MACE (sudden cardiac death 8.1%, sustained ventricular arrhythmias 21.6%, and heart transplant 4.1%). Independent predictors for the appearance for MACE were a CMR study showing severe late gadolinium enhancement, male sex, and practicing sports. CONCLUSIONS: CMR is a key tool for diagnosing LDAC. Characteristic findings are subepicardial fatty infiltration and midwall-subepicardial late gadolinium enhancement. The prognosis of this population is poor with a high incidence of sudden cardiac death and ventricular arrhythmias

Validity of a clinical scale in predicting the failure of non-invasive ventilation in hypoxemic patients.

INTRODUCTION: The HACOR scale is a clinical score that can predict early failure of NIV in hypoxemic acute respiratory failure (ARF) The aim of this study is to analyze the validity of the HACOR scale. METHODS: A retrospective study of a cohort of over 2749 episodes on 2711 consecutive patients requiring NIV for hypoxemic ARF in a polyvalent intensive care unit. The scale was measured before starting NIV and at 1, 6, 12, 24 and 48 h after the initiation of NIV. RESULTS: NIV failure occurred in 963 patients (35%). The value of the HACOR scale before NIV did not differ between success and failure. However, at 1, 6, 12, 24 and 48 h of NIV, the scale values clearly differed between the two groups. The HACOR scale at NIV initiation accurately predicts NIV failure in the first hour, with an optimal cut-off value of 8 points. The AUC for predicting NIV failure with HACOR at 1 h is greater than 0.9 in patients with pneumonia and adult respiratory distress syndrome (ARDS). CONCLUSIONS: The HACOR scale measured at 1 h after NIV initiation accurately predicts NIV failure, especially in pneumonia and ARDS.

Importance of cardiac magnetic resonance findings in the diagnosis of left dominant arrythmogenic cardiomyopathy.

INTRODUCTION AND OBJECTIVES: Left dominant arrhythmogenic cardiomyopathy (LDAC) has recently been recognized as falling on the spectrum of arrhythmogenic cardiomyopathy. It is characterized by fibroadipose replacement of the left ventricle. The aim of this study was to describe the most frequent forms of clinical presentation of LDAC, imaging findings, and events at follow-up, highlighting the importance of cardiac magnetic resonance (CMR). METHODS: Prospective registry of patients with findings compatible with LDAC. CMR image analysis and clinical follow-up was performed. The primary endpoint was the appearance of major adverse cardiovascular events (MACE) during follow-up, defined as sudden cardiac death, sustained ventricular arrhythmias, and heart transplant. RESULTS: We included 74 consecutive patients (mean age, 48.6 years; 50 men [67.6%]). The most frequent CMR indications were chest pain with normal coronary angiography, ventricular arrhythmias, and suspicion of cardiomyopathies. The main CMR findings were midwall and/or subepicardial pattern of late gadolinium enhancement (91.9%), fatty epicardial infiltration (83.8%), and left ventricle segmental contractility abnormalities (47.9%). At a mean follow-up of 3.74 years, 24 patients (32.4%) had a MACE (sudden cardiac death 8.1%, sustained ventricular arrhythmias 21.6%, and heart transplant 4.1%). Independent predictors for the appearance for MACE were a CMR study showing severe late gadolinium enhancement, male sex, and practicing sports. CONCLUSIONS: CMR is a key tool for diagnosing LDAC. Characteristic findings are subepicardial fatty infiltration and midwall-subepicardial late gadolinium enhancement. The prognosis of this population is poor with a high incidence of sudden cardiac death and ventricular arrhythmias.

One-year efficacy and safety of prasugrel and ticagrelor in patients with acute coronary syndromes: Results from a prospective and multicentre ACHILLES registry.

BACKGROUND: Prasugrel and ticagrelor have demonstrated higher efficacy than clopidogrel in their main clinical trials for patients with acute coronary syndrome (ACS). However, the long-term prognosis and different clinical characteristics related to the type of antiplatelet prescription in current clinical practice ACS patients have not been analysed in depth. The objective of this study was to analyse the clinical profile of ACS and the efficacy and safety of novel oral P2Y12 inhibitors in current clinical practice patients discharged afterACS. METHODS: We collected data from the ACHILLES registry, and an observational, prospective and multicentre registry of patients discharged after ACS. We analysed baseline characteristics, clinical profile and therapy during ACS admission and compared with the different treatments at discharge. After 1 year of follow-up, ischaemic and major bleeding events were analysed. Multivariate Cox regression analysis and Kaplan Meier curves were also plotted. RESULTS: Of 1717 consecutive patients, 1294 (75.4%) were discharged with a P2Y12 inhibitor without oral anticoagulation. Novel oral P2Y12 inhibitors were indicated in 47%. Patients treated with clopidogrel were elderly (69.1 ± 13.4 vs 60.4 ± 11.5 years; P < .001) and had a higher prevalence of cardiovascular risk factors. GRACE and CRUSADE scores were higher in the clopidogrel than in novel oral P2Y12 inhibitors group (P < .001). After 1 year of follow-up, 64(5.0%/year) patients had a new myocardial infarction, 127(10.0%/year) had a major adverse cardiovascular event (MACE) and 78(6.1%/year) died. Patients treated with clopidogrel had a significantly higher annual rate of cardiovascular mortality, MACE and all-cause mortality (allP < .001) without differences in major bleeding (P = .587) compared with novel oral P2Y12 inhibitors. After multivariate adjustment for the main clinical variables related to adverse prognosis in ACS patients, the discharge with novel oral P2Y12 inhibitors therapy was independently associated with lower risk of all-cause mortality (HR0.49, 95% CI [0.24-0.98], P = .044) and lower risk of MACE (HR0.64, 95% CI [0.41-0.98], P = .044). CONCLUSIONS: In this prospective, observational and current clinical practice ACS registry, the use of novel oral P2Y12 inhibitors was associated with a reduction in adverse events compared with clopidogrel in patients with ACS. Novel oral P2Y12 inhibitors prescription at discharge was independently associated with lower all-cause mortality and MACE without differences in bleeding events. However, clopidogrel remained the most common P2Y12 inhibitor employed for ACS, especially in older and high-risk patients.

Resultados de un taller de cricotiroidotomía quirúrgica con un modelo de tráquea de cerdo / Results of a surgical cricothyrotomy workshop with a pig trachea model

Introducción: Las últimas guías de la Difficult Airway Society recomiendan que todos los anestesiólogos deberían estar entrenados para la realización de una cricotiroidotomía quirúrgica (CtQ). El objetivo de este estudio es analizar los resultados de aprendizaje de un taller de CtQ mediante la evaluación de la tasa de éxito y el tiempo necesario para realizarla en un modelo de tráquea porcina. Material y métodos: Diseñamos un taller en el que cada alumno respondía un cuestionario con datos demográficos y conocimientos teóricos sobre el abordaje quirúrgico de la vía aérea. Durante la hora siguiente se revisaron aspectos teóricos. Se mostró el modelo y realizamos una CtQ siguiendo la técnica clásica. Después, en grupos de 3-4 alumnos con un instructor, los alumnos realizaron 6 CtQ cada uno. Registramos si la ventilación era correcta, el tiempo necesario para realizarla y la facilidad de realización evaluada por alumno e instructor. Finalmente, los alumnos respondieron un cuestionario de aspectos teóricos. Realizamos un análisis estadístico, considerando estadísticamente significativo un valor de p<0,05. Resultados: Llevamos a cabo 8 ediciones del taller, con 91 alumnos. Consiguieron hacer la CtQ y ventilar correctamente el 86% en el primer intento y el 92% en el sexto (p<0,0001). El tiempo necesario para hacer una CtQ pasó de 163 [107-211] a 70 [55-85] segundos (p<0,0001). Al final del taller los alumnos habían mejorado sus conocimientos teóricos (p<0,0001) y la percepción de facilidad de la técnica. Conclusión: El taller realizado mejora los conocimientos teóricos y la competencia en la realización de una CtQ

Background: The latest Difficult Airway Society (DAS) guidelines recommend that all anaesthesiologists should to be trained in the performing of a surgical cricothyrotomy (CtQ). The aim of this study was to analyse the learning results of a CtQ workshop by assessing the success rate and time to perform CtQ on a porcine tracheal model. Material and methods: A workshop was designed in which each student completed a questionnaire with demographic data and theoretical knowledge about surgical approaches of airway. During the following hour, a review was presented theoretical aspects of CtQ. The model was shown and a CtQ was performed using a classical technique. Afterwards, in groups of 3-4 students with an instructor, each one of the students performed 6 CtQ. A record was made on whether the ventilation was correct, the time to perform CtQ, and the ease of performing the CtQ by the students and instructors. Finally, students completed a questionnaire on the theoretical aspects. Students and instructors performed a workshop debriefing. A statistical analysis was performed, considering a P-value <0.05 as statistically significant. Results: A total of 8 workshop sessions were held with a total of 91 students. At first attempt, 86% of students performed a CtQ with successful ventilation, and 92% at the sixth attempt (P<.0001). Time taken was 163 [107-211] seconds at first attempt, and 70 [55-85] seconds at the sixth (P<.0001). At the end of workshop, students had improved their theoretical knowledge (P<.0001) and perception of the ease of the technique. Conclusion: Workshop performance improved theoretical knowledge and competence in surgical cricothyrotomy

Results of a surgical cricothyrotomy workshop with a pig trachea model. / Resultados de un taller de cricotiroidotomía quirúrgica con un modelo de tráquea de cerdo.

BACKGROUND: The latest Difficult Airway Society (DAS) guidelines recommend that all anaesthesiologists should to be trained in the performing of a surgical cricothyrotomy (CtQ). The aim of this study was to analyse the learning results of a CtQ workshop by assessing the success rate and time to perform CtQ on a porcine tracheal model. MATERIAL AND METHODS: A workshop was designed in which each student completed a questionnaire with demographic data and theoretical knowledge about surgical approaches of airway. During the following hour, a review was presented theoretical aspects of CtQ. The model was shown and a CtQ was performed using a classical technique. Afterwards, in groups of 3-4 students with an instructor, each one of the students performed 6 CtQ. A record was made on whether the ventilation was correct, the time to perform CtQ, and the ease of performing the CtQ by the students and instructors. Finally, students completed a questionnaire on the theoretical aspects. Students and instructors performed a workshop debriefing. A statistical analysis was performed, considering a P-value <0.05 as statistically significant. RESULTS: A total of 8 workshop sessions were held with a total of 91 students. At first attempt, 86% of students performed a CtQ with successful ventilation, and 92% at the sixth attempt (P<.0001). Time taken was 163 [107-211] seconds at first attempt, and 70 [55-85] seconds at the sixth (P<.0001). At the end of workshop, students had improved their theoretical knowledge (P<.0001) and perception of the ease of the technique. CONCLUSION: Workshop performance improved theoretical knowledge and competence in surgical cricothyrotomy.

Conservatively managed patients with non-ST-segment elevation acute coronary syndrome are undertreated with indicated medicines.

INTRODUCTION AND AIMS: Patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) are often managed conservatively. Clinical practice guidelines recommend treating these patients with the same pharmacological drugs as those who receive invasive treatment. We analyze the use of new antiplatelet drugs (NADs) and other recommended treatments in people discharged following an NSTE-ACS according to the treatment strategy used, comparing the medium-term prognosis between groups. METHODS: Prospective observational multicenter registry study in 1717 patients discharged from hospital following an ACS; 1143 patients had experienced an NSTE-ACS. We analyzed groups receiving the following treatment: No cardiac catheterization (NO CATH): n = 134; 11.7%; Cardiac catheterization without revascularization (CATH-NO REVASC): n = 256; 22.4%; percutaneous coronary intervention (PCI): n = 629; 55.0%; and coronary artery bypass graft (CABG): n = 124; 10.8%. We assessed major adverse cardiovascular events (MACE), all-cause mortality, and hemorrhagic complications at one year. RESULTS: NO CATH was the oldest, had the most comorbidities, and was at the highest risk for ischemic and hemorrhagic events. Few patients who were not revascularized with PCI received NADs (NO CATH: 3.7%; CATH-NO REVASC: 10.6%; PCI: 43.2%; CABG: 3.2%; p<0.001). Non-revascularized patients also received fewer beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARB), and statins (p<0.001). At one year, MACE incidence in NO CATH group was three times that of the other groups (30.1%, p<0.001), and all-cause mortality was also much higher (26.3%, p<0.001). There were no significant differences in hemorrhagic events. Belonging to NO CATH group was an independent predictor for MACE at one year in the multivariate analysis (HR 2.72, 95% CI 1.29-5.73; p = 0.008). CONCLUSIONS: Despite current invasive management of NSTE-ACS, patients not receiving catheterization are at very high risk for under treatment with recommended drugs, including NADs. Their medium-term prognosis is poor, with high mortality. Patients treated with PCI receive better pharmacological management, with high use of NADs.

Therapeutic management and one-year outcomes in elderly patients with acute coronary syndrome.

BACKGROUND: Elderly represents a subgroup of high-risk ACS patients due to their advanced age and other comorbidities. Unfortunately, they are also often under-represented in many studies and clinical trials. Furthermore, cardiologists commonly find difficulties in the choice of the antiplatelet treatment and even on whether invasive revascularization should be used. In this study, the management of elderly ACS patients regarding antiplatelet therapy and revascularization procedures will be analyzed. METHODS: 1717 ACS patients were consecutively included in this study from 3 tertiary Hospitals in the Southeast of Spain. Of them, 529 (30.8%) were ≥ 75 years. They were mainly male (60.7%) with a mean age of 81.4±4.7 years. Clinical characteristics, treatment received (antiaplatelet therapy, revascularization) and outcome were analyzed. RESULTS: Regression analysis showed that being ≥ 75 years is independently associated with neither performing catheterization (79.6% vs 97.1%), nor revascularization (51.8% vs 72.5%), being the medical conservative treatment the election in these elderly patients (40.6% vs 18.9%) (p < 0.001 for all). Furthermore, ticagrelor prescription were significantly decreased in older patients (11.5% vs 19.6%; p < 0.001). Regarding patients outcome after one-year of follow-up, being ≥ 75 years was associated with death, major adverse cardiac events (MACE) and major bleeding (all of them p < 0.001). Importantly, nor performing catheterization was independently associated with MACE and death in Cox multivariate analysis in elderly patients. CONCLUSIONS: Elderly patients with ACS are undertreated both invasively and pharmacologically, and this fact might be associated with the observed worse outcomes.

Ventana sagital paramedial oblicua para el acceso de la rama medial del nervio raquídeo posterior guiado ecográficamente / Ultrasound guided parasagittal obliqua aproach for lumbar medial branch block

Objetivos: el método de abordaje ecográfico más utilizado para el bloqueo del ramo medial del nervio raquídeo posterior (RmNRp) requiere de la utilización de una técnica ecográfica biplanar con punción guiada en plano en ventana transversal, para situar la cánula perpendicular al RmNRp, limitando la realización de radiofrecuencia. La utilización de una ventana ecográfica parasagital oblicua permite el acceso al RmNRp permitiendo situar la cánula de forma paralela al nervio, logrando estímulos sensitivos y motores, y posibilitando la realización de radiofrecuencia térmica para segmentos lumbares por encima de L5.En el presente estudio valoramos la eficacia de este nuevo abordaje ecográfico mediante la comprobación fluoroscópica de la situación de la cánula y la comprobación de la obtención de estímulos sensitivos y motores. Material y métodos: se estudian 31 pacientes diagnosticados de síndrome facetario propuestos para la realización de bloqueos de RmNRp diagnósticos. Describimos cuatro ventanas ecográficas lumbares secuenciales necesarias para incluir los pacientes en el estudio. Una vez obtenidas, se localiza el punto objetivo utilizando una ventana parasagital oblicua para lograr la visualización de la cara externa de la apófisis articular superior y la parte más dorsal de la apófisis transversa. Se realiza punción guiada en plano hasta situar la punta en la unión entre apófisis articular superior y apófisis transversa. Una vez situada la cánula en el objetivo se procede a estímulo sensitivo 50 Hz y motor 2Hz para reposicionar la cánula en caso de no obtenerse estímulos. Una vez obtenido estímulo motor o sensitivo o ambos, se realiza una proyección fluoroscópica oblicua 30° y caudo-craneal para comprobar la localización de la punta de la aguja. Resultados: en el 16% de los pacientes no se pueden identificar las 4 ventanas ecográficas por lo que se aborta el procedimiento. En el 84% restante se consigue situar la aguja en el punto target en el 100% de los casos en el primer intento o con un sólo reposicionamiento de la aguja. Conclusión: la ventana ecográfica parasagital oblicua nos permite una aproximación tangencial al RmNRp lumbar con un alto índice de éxito para situar la cánula de radiofrecuencia de forma similar a cuando utilizamos fluoroscopia. La identificación de las cuatro ventanas ecográficas descritas en el estudio nos permite hacer un cribado de los pacientes tributarios a ecografía para el bloqueo de RmNRp (AU)

Objectives: The most used ultrasound guided medial branch block method requires the use of a biplane ultrasound technique. Using this technique the cannula is positioned not parallel to the medial branch by limiting their use to perform conventional radiofrequency. Using a sonographic parasagittal obliqua view allows placing the cannula parallel to the nerve, achieving sensory and motor stimuli and making possible radiofrequency above L5 lumbar segments. In the present study we determined the effectiveness of this new approach by using fluoroscopy and by obtention of sensory and motor stimuli. Material and methods: Thirty-one patients diagnosed with lumbar facet joint pain proposed for diagnostic medial branch blocks were studied. We describe four lumbar sequential sonographic views necessary to include patients in the study. Once obtained, the target point is located using a parasagittal oblique sonographic view to achieve the external face of the superior articular process and the more dorsal part of the transverse process. Puncture is performed guided in plane to place the tip at the junction between superior articular process and transverse process. Once the cannula located in the target proceeds to sensory stimulus 50 Hz and Motor 2 Hz to perform a cannula repositioning in case there were no stimuli. Once obtained either motor or sensory stimulus a caudal to craneal 30° oblique projection is performed by fluoroscopy to check the location of the needle tip. Results: In 16% of patients cannot identify the four ultrasound views so the procedure is aborted. In the remaining 84% is achieved by placing the needle into the target point at 100% of the cases on the first attempt or by once a repositioning of the needle. Conclusion: Ultrasound oblique parasagittal view allows us a tangential approach to the lumbar medial branch with a high rate of success to position the radiofrequency cannula similar to when using fluoroscopy. The sonographic identification of the four windows described in the study allows us to screening tributary patient for ultrasound medial branch blocks (AU)