Predictors of success of high-flow nasal cannula in the treatment of acute hypoxemic respiratory failure. / Predictores de éxito del tratamiento con cánula nasal de alto flujo en el fallo respiratorio agudo hipoxémico.

BACKGROUND: High-flow nasal cannula (HFNC) therapy is used in the treatment of acute respiratory failure (ARF) and is both safe and effective in reversing hypoxemia. In order to minimize mortality and clinical complications associated to this practice, a series of tools must be developed to allow early detection of failure. The present study was carried out to: (i)examine the impact of respiratory rate (RR), peripheral oxygen saturation (SpO2), ROX index (ROXI=[SpO2/FiO2]/RR) and oxygen inspired fraction (FiO2) on the success of HFNC in patients with hypoxemic ARF; and (ii)analyze the length of stay and mortality in the ICU, and the need for mechanical ventilation (MV). METHODS: A retrospective study was carried out in the medical-surgical ICU of Hospital de Montilla (Córdoba, Spain). Patients diagnosed with hypoxemic ARF and treated with HFNC from January 2016 to January 2018 were included. RESULTS: Out of 27 patients diagnosed with ARF, 19 (70.37%) had hypoxemic ARF. Fifteen of them (78.95%) responded satisfactorily to HFNC, while four (21.05%) failed. After two hours of treatment, RR proved to be the best predictor of success (area under the ROC curve [AUROC] 0.858; 95%CI: 0.63-1.05; P=.035). For this parameter, the optimal cutoff point was 29rpm (sensitivity 75%, specificity 87%). After 8hours of treatment, FiO2 and ROXI were reliable predictors of success (FiO2: AUROC 0.95; 95%CI: 0.85-1.04; P=.007 and ROXI: AUROC 0.967; 95%CI: 0.886-1.047; P=.005). In the case of FiO2 the optimal cutoff point was 0.59 (sensitivity 75%, specificity 93%), while the best cutoff point for ROXI was 5.98 (sensitivity 100%, specificity 75%). Using a Cox regression model, we found RR<29rpm after two hours of treatment, and FiO2<0.59 and ROXI>5.98 after 8hours of treatment, to be associated with a lesser risk of MV (RR: HR 0.103; 95%CI: 0.11-0.99; P=.05; FiO2: HR 0.053; 95%CI: 0.005-0.52; P=.012; and ROXI: HR 0.077; 95%CI: 0.008-0.755; P=.028, respectively). CONCLUSIONS: RR after two hours of treatment, and FiO2 and ROXI after 8hours of treatment, were the best predictors of success of HFNC. RR<29rpm, FiO2<0.59 and ROXI>5.98 were associated with a lesser risk of MV.

Soporte respiratorio de alto flujo con cánula nasal / No disponible

La oxigenoterapia es la primera medida a tomar ante un paciente con insuficiencia respiratoria. Los sistemas utilizados pueden ser de bajo o de alto flujo, según suplan o no la necesidad de flujo del paciente. Desde hace algún tiempo, se ha añadido a este arsenal terapéutico el alto flujo con cánula nasal (AFCN), dispositivo que utiliza una mezcla de aire y oxígeno, calentado y humidificado. Entre las ventajas que tiene podemos citar la mayor fiabilidad de la fracción inspirada de oxígeno (FiO2), mejor tolerancia y confort, lavado de espacio muerto orofaríngeo y disminución del esfuerzo inspiratorio. Estas propiedades sitúan al AFCN por encima de la simple oxigenoterapia, haciéndola muy útil en el tratamiento del paciente con insuficiencia respiratoria aguda y crónica

Oxygen therapy is the first step to take in a patient with respiratory failure. The systems can be low or high flow, as fit or not fit the patient´s flow demand. For some time, we have a news device that has been added to the therapeutic arsenal, high flow nasal cannula (HFNC). These devices use a mixture of air and oxygen, heated and humidified. Among the advantages we can cite the increased reliability of the inspiratory oxygen fraction (FiO2), better tolerance and comfort, washing oropharyngeal dead space and decreased inspiratory effort. These properties place the HFNC above simple oxygen therapy, making it very useful in the treatment of patients with chronic and acute respiratory failure

Manejo de una vía aérea difícil en el medio prehospitalario / No disponible

El manejo óptimo de la vía aérea y ventilación de pacientes críticos sigue siendo un pilar básico en la supervivencia, evolución y pronóstico; la intubación orotraqueal (IOT) es el gold standard en estas situaciones. Conocer la posición, lasmaniobras y el material “facilitador” de la IOT, así como realizar una oxigenación-ventilación previa y una sedorrelajación adecuadas, aumentará de forma significativa las posibilidades de éxito.Hay ocasiones en las que, aun siendo ortodoxos en la realización de la técnica, no conseguimos el fin deseado (no intubación, no ventilación), definiéndose tal situación como vía aérea difícil (VAD). Los médicos y enfermeros de Atención Primaria deben estar preparados ante tal eventualidad y disponer del material y la formación necesarios para hacer frente a este momento crítico en el manejo de pacientes graves.Basándonos en las directrices y guía clínicas de las principales sociedades científicas en el manejo de la vía aérea (Grupo Español para el Manejo de la Vía Aérea [GEMVA], Sociedad Americana de Anestesiología [ASA] y el Colegio Americano de Cirujanos), presentamos una revisión de las alternativas recomendadas, centrándonos en una somera descripción del material y una más amplia exposición de la técnica

Optimum management of the airway and ventilation incritical patients continues to be a basic cornerstone in survival, evolution and prognosis. orotracheal intubation (OTI) is the “gold standard” in these situations. Knowing the position, maneuvers and material that “facilitate” the OTI and how to perform previous adequate oxygen-ventilation and sedoanalgesia will significantly increase the possibilities ofsuccess.There are times when, although being orthodox in thetechnique performance, we do not achieve the desired purpose (no intubation, no ventilation), defining such a situation as difficult airway (DAW). Primary Health Care physicians and nurses should be prepared for this and have the necessary material and training to face this critical moment in the management of severe patients.Taking the clinical guidelines of the principal scientific societies into account in the management of the airway (Spanish Group for the Management of the Airway [GEMVA], American Society of Anesthesiology [ASA], and the American College of Surgeons), we present a review of the alternatives recommended, focusing on a brief description of the material and a more extensive presentation of the technique