Accurate evaluation of mechanical ventilation and spontaneous respiratory activity / 中华危重病急救医学

Maintenance of spontaneous effort during mechanical ventilation has long been recognized to improve oxygenation. Such effort has been considered beneficial because oxygenation is a key management aim. However, accumulating evidence indicates that spontaneous effort during mechanical ventilation may cause or worsen acute lung injury. Recently, effort-dependent lung injury has been termed as patient-self inflicted lung injury (P-SILI). This paper describes pathophysiological changes of ventilation-induced lung injury (VILI) induced by mechanical ventilation and spontaneous breathing, and the role of spontaneous breathing during mechanical ventilation in acute respiratory distress syndrome (ARDS). Studies have shown that spontaneous breathing is a double-edged sword, depending on the intensity of spontaneous breathing activity and the severity of lung injury. Future studies are needed to determine ventilator strategies minimizing injury.

Spontaneous breathing during mechanical ventilation in acute respiratory distress syndrome patients / 中国小儿急救医学

Mechanical ventilation is the most important support for acute respiratory distress syndrome (ARDS) patients. Spontaneous breathing (SB) can promote pulmonary revascularization,improve ventilation/blood flow ratio,improve pulmonary blood perfusion distribution,improve gas exchange,prevent ventilator-related diaphragmatic injury,improve systemic hemodynamics and organ perfusion,reduce lung in-jury and inflammatory responses,and shorten mechanical ventilation time and ICU hospitalization time. How-ever,strong SB can lead to excessive tidal volume and inestimable transpulmonary pressure (PL),increasing the risk of lung injury and thus mortality. Lacking of effective respiratory mechanics monitoring remains ques-tions for pediatric patients. When conducting mechanical ventilation on ARDS patients, whether to retain spontaneous respiration rely on the severity of the disease. In general,SB tends to be retained in mild to mod-erate ARDS patients. Respiratory mechanics monitoring in children including tidal volume ( Vt), platform pressure (Pplat),PL,and esophageal pressure (Pes) help to manage the spontaneous breathing during me-chanical ventilation in order to reduce the risk of lung injury.

Extubación fallida en una unidad de cuidados intensivos de la Ciudad de México / Failed extubation in an intensive care unit of Mexico City

Resumen: ANTECEDENTES: el soporte ventilatorio invasivo es una medida terapéutica de uso común en las unidades de cuidados intensivos; una vez aliviada la enfermedad que ocasionó el apoyo ventilatorio se inicia con el retiro de esta modalidad. Cuando se realiza el retiro puede ocurrir una extubación fallida incluso en 20% de los pacientes, requiriendo reintubación. OBJETIVO: reportar la frecuencia de extubación fallida en la Unidad de Cuidados Intensivos Adultos del Hospital 1° de Octubre del ISSSTE. MATERIAL Y MÉTODO: estudio analítico, observacio4nal y transversal, realizado en la Unidad de Cuidados Intensivos, en el que se analizaron expedientes en el periodo del 1 de marzo de 2014 al 28 de febrero de 2015, con apoyo de ventilación mecánica invasiva por más de 24 horas y que se extubaron después de una prueba de ventilación espontánea exitosa. RESULTADOS: se incluyeron 146 expedientes, 74 (51%) fueron de pacientes del sexo femenino, con promedio de edad de 56 años. Las indicaciones de la ventilación mecánica fueron: estado de choque, n=44 (30%), posquirúrgicos, n=40 (27%). El porcentaje de falla del retiro de la ventilación fue de 18%. El riesgo de prevalencia de extubación fallida fue: midazolam OR 4.8 (IC95% 1.56-14.8, p=0.002), obesidad OR 2.5 (IC95% 1.07-6.16), deterioro neurológico como indicación de ventilación OR 6 (IC95% 3.14-11.8), acidosis metabólica OR 5.2 (IC95% 1.2-22.6). CONCLUSIONES: la prevalencia de extubación fallida en nuestra unidad de cuidados intensivos es de 18%, similar a lo reportado en la bibliografía.

Abstract: BACKGROUND: Invasive ventilatory support is a therapeutic measure commonly used in the Intensive Care Units, cured the disease that caused the ventilatory support begins with withdrawal of this modality. Once the withdrawal is performed, a failed extubation can occur in up to 20% of patients, requiring reintubation. OBJECTIVE: To report the frequency of failed extubation in the Adult Intensive Care Unit from the Hospital 1° de Octubre, ISSSTE, Mexico. MATERIAL AND METHOD: An analytical, observational and transversal study was made in the intensive care unit; files were analyzed in the period from March 1st, 2014 to February 28, 2015, with support of mechanical ventilation for more than 24 hours and extubated after a successful spontaneous breath trail. RESULTS: One hundred forty-six records were identified, 74 (51%) were female, with a mean age of 56 years. The indications for mechanical ventilation were: shock state 44 (30%), postoperative 40 (27%). The percentage of ventilation withdrawal failure was 18%. The risk of prevalence for failed extubation: for midazolam OR 4.8 (95% CI 1.56-14.8, p=0.002), obesity OR 2.5 (95% CI 1.07-6.16), neurological deterioration as an indication of ventilation OR 6 (95% CI 3.14-11.8), metabolic acidosis OR 5.2 (95% CI 1.2-22.6). CONCLUSIONS: The prevalence of failed extubation in our intensive care unit is 18%, similar to that reported in the literature.