RÉSUMÉ
Resumen: El uso de la pausa al final de la inspiración (PFI) en ventilación mecánica data de hace más de 50 años y con mayor impulso en la década de los 70, se le atribuye una mejoría en la presión parcial de oxígeno arterial (PaO2) al incrementar la presión media de la vía aérea (Pma), mayor aclaramiento de la presión parcial de dióxido de carbono arterial (PaCO2) y permite la monitorización de la presión meseta (Pmeseta) en la mecánica ventilatoria; sin embargo, los estudios clínicos sobre su uso son escasos y controversiales. En este artículo se abordan los mecanismos fisiológicos, fisiopatológicos y la evidencia sobre el uso de la PFI en ventilación mecánica (VM).
Abstract: The use of the end inspiratory pause (EIP) in mechanical ventilation has been going on for more than 50 years and with greater momentum in the 1970s, an improvement in the partial pressure of arterial oxygen (PaO2) is attributed to the increase mean airway pressure, greater clearance of partial pressure of arterial carbon dioxide and allows monitoring of plateau pressure in ventilatory mechanics; However, the Clinical studies on its use are few and controversial. This article addresses the physiological and pathophysiological mechanisms and the evidence on the use of EIP in mechanical ventilation.
Resumo: A utilização da pausa ao final da inspiração (PFI) na ventilação mecânica remonta a mais de 50 anos e com maior impulso na década de 70, atribui-se uma melhora na pressão parcial de oxigênio arterial (PaO2) pelo aumento da pressão média das vias aéreas (Pma), uma maior depuração da pressão parcial de dióxido de carbono arterial (PaCO2) e permite a monitorização da pressão de platô (Pplateau) na mecânica ventilatória, porém estudos Os dados clínicos sobre seu uso são escassos e controversos. Este artigo aborda os mecanismos fisiológicos e fisiopatológicos e as evidências sobre o uso do PFI na ventilação mecânica (VM).
RÉSUMÉ
In anesthesia practice, mechanical ventilation is a fundamental tool, and its correct configuration is essential in the patients care. Airway pressure is often assumed to reflect the forces applied to the lung and is used to monitor mechanical ventilation. This assumption is erroneous because pressure acts on the respiratory system as a whole and the impact on its components will depend on the ratio of lung and respiratory system elastances. In turn, patients' lungs with the same body size and ventilated with the same tidal volume, may be subjected to different forces depending on their functional size. This is expressed under the concepts of stress and strain. Its surrogate owners, the Paw plateau and the Vt, have shown a poor correlation compared to transpulmonary pressure and the airway driving pressure. This review aims to provide the theoretical-practical tools necessary to optimize mechanical ventilation for each patient.
En la práctica anestésica, la ventilación mecánica es una herramienta fundamental, y su correcta configuración es esencial en el cuidado de los pacientes. La presión de la vía aérea es, muchas veces, asumida como el reflejo de las fuerzas aplicadas en el pulmón y es utilizada para monitorizar la ventilación mecánica. Esta asunción es errónea porque la presión actúa sobre el sistema respiratorio en su totalidad y la repercusión sobre sus componentes va a depender de la relación de elastancias del pulmón y el sistema respiratorio. A su vez, los pulmones de pacientes con el mismo tamaño corporal y ventilados con el mismo volumen corriente, pueden estar sujetos a diferentes fuerzas dependiendo de su tamaño funcional. Esto es expresado bajo los conceptos de stress y strain. Sus respectivos subrogantes, Pawplateau y el Vt, han demostrado tener una pobre correlación en comparación con la presión transpulmonar y la airway driving pressure. Esta revisión pretende brindar las herramientas teórico-prácticas necesarias para optimizar la ventilación mecánica para cada paciente.
Sujet(s)
Humains , Ventilation artificielle , Stress physiologique , Mécanique respiratoire/physiologie , Pression , ÉlasticitéRÉSUMÉ
Objective To find out whether we can get the optimality in the prognosis of acute respiratory distress syndrome (ARDS) by combing the pressure parameters in mechanical ventilation with traditional PaO2/FiO2.Methods This is a retrospective study.Patients included here were diagnosed as ARDS in the Emergency Unit (EICU) of the First Affiliated Hospital of China Medical University fiom January 2018 to December 2018.All the patients were intubated and mechanically ventilated.Patients with a short observation time (＜ 48 h) or unable to cooperate with treatment were excluded.According to the patient's 28-day survival,patients were divided into the survival and non-survival groups.Parameters in the two groups such as basic characteristics,SOFA score,non-respiratory system SOFA score (nR-SOFA),and PaO2/FiO2 were analyzed with LSD-t test or rank sum test.Simultaneously,plateau pressure,driving pressure,mean airway pressure and the ratio of these mechanical ventilation pressure parameters to the PaO2/FiO2 were also analyzed.Results A total of 147 patients were included in the study and 117 of them were analyzed.The overall 28-day mortality was 31.62％ (n=37).There were no significant differences in gender,age,body mass index,initial arterial oxygen partial pressure and carbon dioxide partial pressure between the survival group and non-survival groups (P ＞0.05).But there was a significant difference in SOFA score(6.53 ± 2.96 vs 8.65 ± 3.00) and nR-SOFA(3.44 ± 2.98 vs 5.27 ± 2.86).Among the evaluation indexes,the PPOI obtained the AUC of 0.828,with the sensitivity of 86.5％,and specificity of 71.2％.The AUC of the SOFA score was 0.707,while the AUC of the PPOI combined with the SOFA score was 0.833.Conclusion Mechanical ventilation pressure parameters can be used to predict the prognosis of patients with ARDS.PPOI may evaluate the prognosis of ARDS in a more simple,timely and real-time manner.