Relación de la presión de distensión pulmonar con la mortalidad en pacientes bajo ventilación mecánica con COVID-19 / Relationship of lung distention pressure with mortality in patients under mechanical ventilation with COVID-19 / Relação da pressão de distensão pulmonar com a mortalidade em pacientes sob ventilação mecânica com COVID-19

Resumen: Objetivo: Determinar la relación de la presión de distensión pulmonar (DP) con la mortalidad en pacientes bajo ventilación mecánica (VM) con COVID-19. Material y métodos: Estudio de cohorte en pacientes con COVID-19 y VM de marzo a septiembre de 2020, se compararon dos grupos, expuesto (pacientes con DP superior a 13 cmH2O) y no expuestos (pacientes con DP igual o menor a 13 cmH2O), se analizó la edad, sexo, hipertensión arterial (HTA), diabetes, obesidad, enfermedad renal crónica (ERC), enfermedad pulmonar obstructiva crónica (EPOC), inmunosupresión y enfermedad cardiovascular. Resultados: Con un total de 90 pacientes, la DP alta mostró ser un factor de riesgo para defunción (p = 0.000) al igual que la HTA (p = 0.013) y la inmunosupresión (p = 0.040). En pacientes hipertensos se encontró una DP de 10 cmH2O como meta de protección pulmonar, la cual se relaciona con la probabilidad de morir en 49.6% incrementando a 89.6% cuando existe una DP de 13 cmH2O. Conclusiones: Ochenta por ciento de la población tiene alto riesgo de mortalidad cuando existe DP alta, e incremento de mortalidad cuando se asocia con HTA e inmunosuprimidos. El resultado más importante fue la relación de mortalidad de la DP en pacientes hipertensos.

Abstract: Objective: To determine the relationship of driving pressure (DP) with mortality in patients under mechanical ventilation (MV) with COVID-19. Material and methods: Cohort study in patients with COVID-19 and MV from March to September 2020, two groups were compared, exposed (patients with DP greater than 13 cmH2O) and unexposed (patients with DP equal to or less than 13 cmH2O), age was analyzed, sex, hypertension (HT), diabetes, obesity, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), immunosuppression, and cardiovascular disease. Results: With a total of 90 patients, high DP was shown to be a risk factor for death (p = 0.000) as well as hypertension (p = 0.013) and immunosuppression (p = 0.040). In hypertensive patients, a DP of 10 cmH2O was found as a lung protection goal, which is related to the probability of dying in 49.6%, increasing to 89.6% when there is a DP of 13 cmH2O. Conclusions: 80% of the population has a high risk of mortality when there is high DP, and an increase in mortality when associated with hypertension and immunosuppression. The most important result was the mortality ratio of DP in hypertensive patients.

Resumo: Objetivo: Determinar a relação da pressão de distensão pulmonar (DP) com a mortalidade em pacientes com COVID-19 com ventilação mecânica (VM). Material e métodos: Estudo de coorte em pacientes com COVID-19 e VM de março a setembro de 2020, foram comparados dois grupos, expostos (pacientes com DP maior que 13 cmH2O) e não expostos (pacientes com DP igual ou menor que 13 cmH2O), analisou-se a idade, sexo, pressão arterial alta (HAS), diabetes, obesidade, DRC, DPOC, imunossupressão e doenças cardiovasculares. Resultados: Com um total de 90 pacientes, a DP elevada mostrou-se fator de risco para óbito (p = 0.000), assim como hipertensão (p = 0.013) e imunossupressão (p = 0.040). Em pacientes hipertensos, encontrou-se uma DP de 10 cmH2O como meta de proteção pulmonar, que está relacionada à probabilidade de morrer em 49.6%, aumentando para 89.6% quando há DP de 13 cmH2O. Conclusões: 80% da população tem alto risco de mortalidade quando há DP elevada, e mortalidade aumentada quando associada à hipertensão e imunossupressão. O resultado mais importante foi a razão de mortalidade da DP em pacientes hipertensos.

Relación entre intensidad de la ventilación mecánica y agravamiento de la disfunción multiorgánica por la COVID-19 / Relationship between intensity of mechanical ventilation and multiple organ dysfunction worsening by COVID-19

RESUMEN Introducción: La intensidad de la ventilación mecánica está reflejada por la presión de conducción dinámica y el poder mecánico. Es un predictor de lesión pulmonar inducida por el ventilador y está asociada a la mortalidad. Objetivo: Determinar si existe relación entre intensidad de la ventilación mecánica y el ΔSOFA>0 (agravamiento) en los pacientes con la COVID-19 a las 72 horas después de la intubación. Material y Métodos: Grupo de estudio conformado por 35 pacientes diagnosticados con la COVID-19 que estuvieron ventilados por más de 72 horas. Se empleó la prueba de Chi cuadrado (X 2 ) o test exacto de Fisher para comparar variables cualitativas; para las cuantitativas se empleó la prueba t de Student o U de Mann-Whitney. Se realizó una Regresión Logística Binaria Simple para encontrar relación de las variables con ΔSOFA dicotomizada para ΔSOFA≤0 y ΔSOFA>0. La capacidad discriminativa de los modelos se evaluó mediante la Curva ROC. Resultados: Presentaron SOFA>0 21 pacientes (60 %). No se encontraron diferencias significativas de la Presión de Conducción entre ambos grupos (15 vs. 18, U=94.00, z= -1,795, p=0,77). Fueron buenas predictoras de ΔSOFA>0 el Poder Mecánico (OR 3,421 [95 % IC1,510 a 7,750, p=0,003]) y el Volumen Tidal (OR 1,03 [95 % IC 1,012 a 1,068], p=0,005). El Modelo Predictivo de ΔSOFA>0 en función del Poder Mecánico (AUC 0,888 [95 % IC 0,775 a 1], p<0,001) mostró una buena capacidad discriminatoria. Conclusiones: El Poder Mecánico está relacionado con el agravamiento de la disfunción multiorgánica en pacientes sometidos a ventilación mecánica por la COVID-19.

ABSTRACT Introduction: The intensity of mechanical ventilation is reflected by driving pressure and mechanical power. It is a predictor of ventilator-induced lung injury and it can be associated with mortality. Objective: To determine if there is a relationship between intensity of mechanical ventilation and ΔSOFA>0 (worsening) in patients with COVID-19 at 72 h after intubation. Material and Methods: Study group composed of 35 COVID-19 patients who were ventilated for more than 72 hours. Chi-square test (X 2 ) or Fisher's exact test was used to compare qualitative variables; Student t test or Mann-Whitney U test was employed for quantitative ones. A Simple Binary Logistic Regression Model was performed in order to find the relationship between variables and dichotomized ΔSOFA for ΔSOFA≤0 and ΔSOFA>0. The discriminatory capacity of the models was tested by using ROC Curve. Results: A total of 21 patients (60 %) presented ΔSOFA>0 (worsening). No significant differences related to Driving Pressure were found between the two groups (15 vs. 18, U=94,00, z= -1,795, p=0,77). Mechanical Power (OR 3,421 [95 % CI 1,510 a 7,750, p=0,003]) and Tidal Volume (OR 1,03 [95 % CI 1,012 a 1,068], p=0,005) were good predictors of ΔSOFA>0. The Predictive Model of ΔSOFA>0 depending on Mechanical Power (AUC 0,888 [95 % CI 0,775 a 1], p<0,001) showed a good discriminatory capacity. Conclusions: Mechanical Power is related to multi-organ dysfunction worsening in mechanically ventilated patients with COVID-19.

Lung protective effect of driving pressure-guided lung protective ventilation strategy combined with pressure-controlled ventilation in elderly patients undergoing thoracoscopic radical resection of lung cancer / 肿瘤研究与临床

Objective:To investigate the lung protective effect of driving pressure-guided lung protective ventilation strategy (LPVS) combined with pressure-controlled ventilation (PCV) in elderly patients undergoing thoracoscopic radical resection of lung cancer.Methods:One hundred elderly patients scheduled for thoracoscopic radical resection of lung cancer from April 2021 to April 2022 in the Second Hospital of Shanxi Medical University were selected. Patients were aged 60-80 years old and American Society of Anesthesiologists (ASA) classification Ⅰ-Ⅱ. All patients were divided into 4 groups by using the random number table method, with 25 cases in each group. Group A received volume-controlled ventilation (VCV) + 5 cm H 2O (1 cm H 2O = 0.098 kPa) PEEP, group B received PCV+5 cm H 2O PEEP, group C received VCV+driving pressure-guided individualized PEEP, and group D received PCV+driving pressure-guided individualized PEEP. The arterial oxygen partial pressure (PaO 2) was recorded before one-lung ventilation (OLV) (T 0), 30 min after OLV (T 1) and 60 min after OLV (T 2). The serum concentrations of neutrophil elastase (NE) in radial artery blood samples of patients were measured at T 0 and 10 min after the end of OLV (T 3). The occurrence of postoperative pulmonary complications (PPC) within 5 d after surgery was recorded. Results:The PaO 2 of group A and B at T 1 [(135±50), (146±51) mmHg (1 mmHg = 0.133 kPa)] and T 2 [(137±46), (143±47) mmHg] were lower than those of group C and group D at T 1 [(168±27), (190±30) mmHg] and T 2 [(180±30), (183±24) mmHg] (all P < 0.05). The incidence of PPC within 5 d after surgery in group A was higher than that in group D [36% (9/25) vs. 4% (1/25)] ( P = 0.005). The concentration of NE at T 3 in group A [(202.8±9.7) ng/ml] was lower than that in group B, C and D [(182.5±12.0), (180.0±10.3), (160.6±13.0) ng/ml] ( P < 0.05). Conclusions:During OLV, driving pressure-guided LPVS combined with PCV can not only improve oxygenation, but also show obvious advantages in reducing inflammatory response. It is a safe and effective intraoperative ventilation strategy for elderly patients undergoing thoracoscopic radical resection of lung cancer.

Effects of driving pressure-guided individualized PEEP ventilation on intraoperative cardiac function in elderly patients undergoing laparoscopic surgery / 中华麻醉学杂志

Objective:To evaluate the effect of driving pressure-guided individualized PEEP ventilation on intraoperative cardiac function in elderly patients undergoing laparoscopic surgery.Methods:Seventy American Society of Anesthesiologists physical statusⅠor Ⅱ patients, aged 60-75 yr, with body mass index of 18-25 kg/m 2, with left ventricular ejection fraction (LVEF)>50%, undergoing elective laparoscopic radical gastrectomy under general anesthesia, were divided into 2 groups ( n=35 each) by the random number table method: conventional PEEP ventilation group (group P) and driving pressure-guided individualized PEEP ventilation group (group D). The patients were mechanically ventilated in the volume-controlled ventilation mode, with a V T of 7 ml/kg, an inspired oxygen concentration of 60%, an inspiratory/expiratory ratio of 1∶2, and an end-inspiratory pause time of 10%.In group P, 5 cmH 2O PEEP was given for ventilation from 5 min after the establishment of pneumoperitoneum until the end of operation.In group D, driving pressure-guided individualized PEEP titration was performed at 5 min after the establishment of pneumoperitoneum, and ventilation was maintained with the titrated individualized PEEP until the pneumoperitoneum was closed.After the pneumoperitoneum was closed, group D underwent driving pressure-directed individualized PEEP again, and ventilation was maintained with re-titrated PEEP until the end of surgery.Before pneumoperitoneum (T 0), at 5 min after establishment of pneumoperitoneum (T 1), 5 min of PEEP ventilation (T 2), 30 min of PEEP ventilation (T 3) and 5 min after the end of pneumoperitoneum (T 4), MAP was recorded, LVEF, global longitudinal strain of left ventricle, tricuspid annular systolic displacement, early diastolic peak velocity (E peak) of mitral valve and tricuspid valve orifice, early diastolic peak velocity (e′) and systole peak velocity (S′) of mitral valve and tricuspid valve annulus were measured using transesophageal ultrasonography, and myocardial performance index (MPI) and E/e′ were calculated. Results:Compared with group P, MAP, LVEF, mitral valve annulus S′, global longitudinal strain of left ventricle, tricuspid valve annulus S′, and tricuspid annular systolic displacement were significantly decreased at T 2 and T 3, and left ventricular MPI, mitral valve E/e′, right ventricular MPI and tricuspid E/e′ were increased in group D ( P<0.05). Conclusions:Driving pressure-guided individualized PEEP ventilation can decrease the cardiac function during pneumoperitoneum in elderly patients undergoing laparoscopic surgery.

Asociación de la presión de impulso y el poder mecánico ventilatorio con la mortalidad en pacientes con COVID-19 grave-crítico / Association of driving pressure and ventilatory mechanical power with mortality in patients with severe-critical COVID-19 / Associação da pressão de impulso e potência mecânica ventilatória com a mortalidade em pacientes com COVID-19 grave em estado crítico

Resumen: Introducción: Una ventilación eficiente es fundamental en COVID-19, pero se debe aplicar un presión de distensión (PD) y el poder mecánico (PM) apropiado. Objetivo: Evaluar la asociación de la presión de distensión y el poder mecánico con la mortalidad en pacientes con COVID-19 grave-crítico. Material y métodos: Estudio observacional, transversal, analítico, retrospectivo. Mediante análisis estadístico bivariado y multivariado se determinó si el DP y el PM se asocian con la mortalidad, considerando significativa una p < 0.05. Resultados: Se incluyeron 137 pacientes con COVID-19 grave-crítico, de edad media 55.8 ± 16.4 años. Las comorbilidades fueron hipertensión arterial 85 (62%), obesidad 62 (45.3%) y diabetes mellitus 50 (36.5%). La mortalidad fue de 71 (52.3%). En enfermedad grave el DP fue de 14.2 ± 5.1 cmH2O y en enfermedad crítica fue de 11.3 ± 5.0 cmH2O (p = 0.001). Los valores medios del PM con COVID-19 grave fueron 19.5 ± 19.3 J/min y en COVID-19 crítico fueron 29.1 ± 27.6 J/min (p = 0.026). El área bajo la curva (AUC) del DP para predecir mortalidad fue de 0.740 (p < 0.001) y del PM 0.569 (p = 0.171). En el análisis multivariado los factores independientemente asociados a mortalidad fueron la edad (ORa = 1.041, IC95% 1.015-1.068, p = 0.002) y el DP (ORa = 1.207, IC95% 1.101-1.322, p < 0.001). Conclusión: La presión de distensión es un predictor independiente y significativo de mortalidad en pacientes con COVID-19 grave- crítico.

Abstract: Introduction: Efficient ventilation is essential in COVID-19 but an appropriate driving pressure (DP) and mechanical power (PM) must be applied. Objective: To evaluate the association of driving pressure and mechanical power with mortality in patients with severe-critical COVID-19. Material and methods: Observational, cross-sectional, analytical, retrospective study. Through bivariate and multivariate statistical analysis, it was determined if the DP and PM are associated with mortality, considering significant a p < 0.05. Results: 137 patients with severe-critical COVID-19, mean age 55.8 ± 16.4 years, were included. The comorbidities were arterial hypertension 85 (62%), obesity 62 (45.3%) and diabetes mellitus 50 (36.5%). Mortality was 71 (52.3%). In severe illness, the DP was 14.2 ± 5.1 cmH2O and in critical illness it was 11.3 ± 5.0 cmH2O (p = 0.001). The mean PM values with severe COVID-19 were 19.5 ± 19.3 J/min and in critical COVID-19 they were 29.1 ± 27.6 J/min (p = 0.026). The AUC of DP to predict mortality was 0.740 (p < 0.001) and of PM 0.569 (p = 0.171). In the multivariate analysis, the factors independently associated with mortality were age (ORa = 1.041, CI95% 1.015-1.068, p = 0.002) and DP (ORa = 1.207, CI95% 1.101-1.322, p < 0.001). Conclusion: Driving pressure is an independent and significant predictor of mortality in patients with severe-critical COVID-19.

Resumo: Introdução: Uma ventilação eficiente é essencial no COVID-19, mas se deve ser aplicar uma driving pressure (DP) e potência mecânica (PM) apropriadas. Objetivo: Avaliar a associação da driving pressure e a potência mecânica com a mortalidade em pacientes com COVID-19 grave-crítico. Material e métodos: Estudo observacional, transversal, analítico, retrospectivo. Por meio de análise estatística bivariada e multivariada, determinou-se se o DP e PM estão associados à mortalidade, considerando significativo um p < 0.05. Resultados: Incluíram-se 137 pacientes com COVID-19 grave-crítico, com idade média de 55.8 ± 16.4 anos. As comorbidades foram hipertensão arterial 85 (62%), obesidade 62 (45.3%) e diabetes mellitus 50 (36.5%). A mortalidade foi de 71 (52.3%). Na doença grave, o DP foi de 14.2 ± 5.1 cmH2O e na doença crítica foi de 11.3 ± 5.0 cmH2O (p = 0.001). Os valores médios de PM com COVID-19 grave foram 19.5 ± 19.3 J/min e em COVID-19 crítico foram 29.1 ± 27.6 J/min (p = 0.026). A AUC de DP para predizer mortalidade foi de 0.740 (p < 0.001) e de PM 0.569 (p = 0.171). Na análise multivariada, os fatores independentemente associados à mortalidade foram idade (ORa = 1.041, IC 95% 1.015-1.068, p = 0.002) e DP (ORa = 1.207, IC 95% 1.101-1.322, p < 0.001). Conclusão: A driving pressure é um preditor independente e significativo de mortalidade em pacientes com COVID-19 grave-crítico.

Effect of driving pressure-guided lung protective ventilation strategy on early postoperative pulmonary function in adults patients undergoing heart valve surgery: A randomized controlled study / 中国胸心血管外科临床杂志

@#Objective    To evaluate the effect of driving pressure-guided lung protective ventilation strategy on lung function in adult patients under elective cardiac surgery with cardiopulmonary bypass. Methods    In this randomized controlled trial, 106 patients scheduled for elective valve surgery via median sternal incision under cardiopulmonary bypass from July to October 2020 at West China Hospital of Sichuan University were included in final analysis. Patients were divided into two groups randomly. Both groups received volume-controlled ventilation. A protective ventilation group (a control group, n=53) underwent traditional lung protective ventilation strategy with positive end-expiratory pressure (PEEP) of 5 cm H2O and received conventional protective ventilation with tidal volume of 7 mL/kg of predicted body weight and PEEP of 5 cm H2O, and recruitment maneuver. An individualized PEEP group (a driving pressure group, n=53) received the same tidal volume and recruitment, but with individualized PEEP which produced the lowest driving pressure. The primary outcome was oxygen index (OI) after ICU admission in 30 minutes, and the secondary outcomes were the incidence of OI below 300 mm Hg, the severity of OI descending scale (the Berlin definition), the incidence of pulmonary complications at 7 days after surgery and surgeons’ satisfaction on ventilation. Results    There was a statistical difference in OI after ICU admission in 30 minutes between the two groups (273.5±75.5 mm Hg vs. 358.0±65.3 mm Hg, P=0.00). The driving pressure group had lower incidence of postoperative OI<300 mm Hg (16.9% vs. 49.0%, OR=0.21, 95%CI 0.08-0.52, P=0.00) and less severity of OI classification than the control group (P=0.00). The incidence of pulmonary complications at 7 days after surgery was comparable between the driving pressure group and the control group (28.3% vs. 33.9%, OR=0.76, 95%CI 0.33-1.75, P=0.48). The atelectasis rate was lower in the driving pressure group (1.0% vs. 15.0%, OR=0.10, 95%CI 0.01-0.89, P=0.01). Conclusion    Application of driving pressure-guided ventilation is associated with a higher OI and less lung injury after ICU admission compared with the conventional protective ventilation in patients having valve surgery.

Impacto de la presión de distensión alveolar en los pacientes con síndrome de distrés respiratorio agudo (SDRA): revisión narrativa / Impact of alveolar distention pressure on days under mechanical ventilation in patients with acute respiratory distress syndrome (SDRA) / Impacto da pressão da distensão alveolar em pacientes com síndrome do desconforto respiratório agudo (SDRA): revisão narrativa

Resumen: Introducción: El síndrome de distrés respiratorio agudo (SDRA) se caracteriza por una heterogeneidad del daño en el parénquima pulmonar; la asociación entre el volumen tidal (Vt) y la distensibilidad pulmonar estática (Cst) puede ser evaluada mediante la presión de distensión (PD). Se desconoce hasta el día de hoy si el control de la PD impacta en otros objetivos, tales como la disminución de los días bajo ventilación mecánica. Material y métodos: Se realizó una revisión de artículos médicos científicos en Pubmed, EMBASE y Medigraphic con las siguientes palabras clave: «driving pressure¼ y «acute respiratory distress syndrome¼ para relacionar la PD y los días libres de ventilación mecánica en los principales estudios sobre SDRA; se analizaron las variables respiratorias reportadas por estas publicaciones y se tomaron estudios de revisión, revisiones sistematizadas y metaanálisis, lo cual fue evaluado por seis de los autores principales. Resultados: Se encontró en la revisión sistematizada la siguiente relación: los pacientes ventilados con SDRA y PD < 15 cmH2O se asociaban con menos días de ventilación mecánica con un valor de p = 0.03; los pacientes ventilados con SDRA y PD < 15 cmH2O, al comparar la mortalidad a 90 días, la disminuían, tomando un valor de p ≤ 0.0001; los pacientes sin SDRA y PD < 15 cm cmH2O, comparando la mortalidad a 28 días con una p = 0.005, las complicaciones pulmonares postoperatorias, la PD < 15 cmH2O y los valores de PD mayores a 15 cmH2O se asociaron con barotrauma, infecciones pulmonares postoperatorias, con una p ≤ 0.0001; en supervivencia y mortalidad a los 90 días, se correlacionó con una razón de momios (RM) de 0.60 a favor de PD < 15 cmH2O, y en mortalidad a 28 días con una RM de 0.29 a favor de la PD menor, al valor de corte. Conclusión: La PD se asocia con mortalidad de manera directamente proporcional y los valores más bajos de PD se asocian con menos días de ventilación mecánica.

Abstract: Introduction: ARDS is characterized by a heterogeneity of damage in the lung parenchyma and the association between tidal volume (Vt) and static lung compliance (Cst) can be evaluated by DP. Most studies on DP and ARDS focus on mortality, showing a lower percentage of survival while the level of DP is higher, however, it is unknown until today whether the control of DP impacts on other objectives such as decrease of days under mechanical ventilation. Material and methods: A systematic review of medical articles in Pubmed, EMBASE and Medigraphic was carried out with key words: driving pressure and acute respiratory distress syndrome to relate DP and days free of mechanical ventilation in the main studies on ARDS, analyzing the respiratory variables reported by these publications. Results: The relationship was found in the systematized review; that patients ventilated with ARDS and DP < 15 cmH2O was associated with fewer days of mechanical ventilation with a p = 0.03, patients with ARDS and DP < 15 cmH2O comparing mortality at 90 days, decreased their mortality with p ≤ 0.0001, patients without ARDS and PD < 15 cm cmH2O comparing mortality at 28 days with p = 0.005, patients with ARDS and DP association of postoperative pulmonary complications and DP < 15 cmH2O, DP values greater than 15 cmH2O was associated with barotrauma, postoperative pulmonary infections, with a p ≤ 0.0001 of, in survival and mortality at 90 days, correlated with a odds ratio (OR) of 0.60 in favor of DP less than 15 cmH2O and in mortality at 28 days with an OR of 0.29, in favor of DP below 15 cmH2O. Discussion: DP is associated with mortality in a directly proportional way. Conclusion: Lower values of DP are associated with fewer days of mechanical ventilation.

Resumo: Introdução: A SDRA é caracterizada pela heterogeneidade do dano do parênquima pulmonar e a associação entre volume corrente (Vt) e complacência pulmonar estática (Cst) pode ser avaliada por pressão de distensão alveolar (PD). Não se sabe até hoje se o controle da PD afeta outros objetivos, como redução de dias sob ventilação mecânica. Material e métodos: Foi realizada uma revisão de artigos médicos científicos no Pubmed, EMBASE e Medigraphic com palavras-chave: pressão de distensão e síndrome do desconforto respiratório agudo para relacionar PD e dias sem ventilação mecânica nos principais estudos de SDRA, analisando as variáveis relatados por essas publicações, realizando estudos de revisão, revisões sistemáticas e meta-análises, sendo avaliados por 6 dos principais autores. Resultados: A relação foi encontrada na revisão sistemática; que ventilaram pacientes com SDRA e PD < 15 cmH2O estiveram associados a menos dias de ventilação mecânica com p = 0.03, pacientes ventilados com SDRA e PD < 15 cmH2O comparando a mortalidade em 90 dias, sua mortalidade diminuiu com p ≤ 0.0001, pacientes sem SDRA e PD < 15 cm cmH2O comparando mortalidade em 28 dias com p = 0.005, associação de complicações pulmonares pós-operatórias e PD < 15 cmH2O, valores de PD maiores que 15 cmH2O foram associados a traumatismo barro, infecções pulmonares pós-operatórias , com p ≤ 0.0001 de, na sobrevida e mortalidade aos 90 dias, foi correlacionada com uma Odds Ratio (RM) de 0.60 a favor da PD menor que 15 cmH2O e na mortalidade aos 28 dias com uma RM de 0.29, a favor do PD menor que o valor de corte. Conclusão: a PD está associada à mortalidade de maneira diretamente proporcional. e valores mais baixos de PD estão associados a menos dias de ventilação mecânica.

Investigation of mechanical ventilation pressure parameters' effect on the prognosis of acute respiratory distress syndrome / 中华急诊医学杂志

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.

¿Limitar la presión de distensión protege contra la lesión pulmonar adquirida por la ventilación mecánica (VALI)? / Does limiting the distension pressure protect against lung injury acquired by mechanical ventilation (VALI)? / A limitação da pressão de distensão protege contra lesão pulmonar adquirida por ventilação mecânica (VALI)?

Resumen: El incremento en la presión de las vías respiratorias causa lesión de la membrana alveolar proponiendo el barotrauma como causa de lesión pulmonar adquirida por el ventilador (VALI), esta afección se presenta de forma frecuente, lo que conduce a entender mejor el papel desempeñado por los ajustes del ventilador mecánico, la fisiopatología pulmonar subyacente y su interacción. En la última década se ha dado relevancia al término presión de distensión (PD), que surge del cálculo del delta de presión (∆P = Vt/CRS). La PD representa los cambios dinámicos de la presión que se genera en la vía aérea en cada ciclo ventilatorio. Aunque se instalen medidas de protección pulmonar de manera inicial, existen diversas condiciones que modifican las propiedades elásticas, tales como reanimación hídrica y el balance positivo de líquidos, procesos infecciosos agregados, etc. Sin embargo, aun cuando se cumplan estas medidas de protección puede haber distensión pulmonar excesiva, por lo que la monitorización de la PD puede ser una herramienta útil para determinar de manera sistemática los cambios en la rigidez pulmonar, estableciendo intervenciones. En ausencia de ensayos que usen PD como objetivo al establecer el ventilador, se sugiere que se utilice como complemento y no como un sustituto de parámetros de protección pulmonar.

Abstract: The increase in airway pressure causes injury in the alveolar membrane by proposing barotrauma as the cause of ventilator-acquired Lung Injury (VALI), this condition occurs frequently, which leads to a better understanding of the roles played by the mechanical ventilator settings, underlying lung pathophysiology and their interaction. In the last decade, the term pressure of distension (PD) has emerged, arising from the calculation of the pressure delta (ΔP = Vt/CRS). The PD represents the dynamic changes of the pressure that is generated in the airway in each ventilatory cycle. Although pulmonary protection measures are initially installed, there are several conditions that modify elastic properties, such as fluid resuscitation and positive fluid balance, aggregated infectious processes, etc. However, even if these protective measures are met, excessive pulmonary distention may occur, so PD monitoring may be a useful tool for systematically determining changes in pulmonary stiffness by establishing interventions. In the absence of assays using PD as a target when establishing the ventilator, it is suggested that it be used as a complement and not as a substitute for pulmonary protection parameters.

Resumo: O aumento da pressão das vias aéreas causa lesão da membrana alveolar, propondo o barotrauma como causa de Lesão Pulmonar Adquirida pelo Ventilador (VALI), esta condição ocorre com frequência, o que leva a uma melhor compreensão dos papéis desempenhados pelos ajustes do ventilador mecânico, a fisiopatologia pulmonar subjacente e sua interação. Na última década, o termo pressão de distensão (PD) tem recebido relevância decorrente do cálculo do delta de pressão (ΔP = Vt/CRS). A DP representa as mudanças dinâmicas da pressão gerada na via aérea em cada ciclo ventilatório. Embora as medidas de proteção pulmonar sejam instaladas inicialmente, existem várias condições que modificam as propriedades elásticas, tais como ressuscitação hídrica e balanço hídrico positivo, processos infecciosos agregados, etc. No entanto, mesmo que essas medidas de proteção sejam atendidas, pode haver distensão pulmonar excessiva, de modo que a monitorização da DP possa ser uma ferramenta útil para determinar sistematicamente as mudanças na rigidez pulmonar, estabelecendo intervenções. Na ausência de ensaios que utilizem a PD como objetivo no estabelecimento do ventilador, sugere-se que seja utilizado como complemento e não como substituto dos parâmetros de proteção pulmonar.