Correlation Analysis between Mechanical Power and Lung Ultrasound Score and Their Evaluation of Severity and Prognosis in ARDS Patients

Abstract

Background and Objective. During mechanical ventilation, the energy delivered by a ventilator to the respiratory system in one minute is defined as mechanical power (MP). It describes the combined effects of several mechanical factors, including tidal volume, driving pressure, transpulmonary pressure, flow rate, positive end-expiratory pressure, and respiratory rate on lung ventilation. As such, MP may be useful for evaluating the severity and prognosis of acute respiratory distress syndrome (ARDS), as improvements in pulmonary ventilation directly affect a patient’s prognosis. Recent advances in lung ultrasound technology make it possible to evaluate lung ventilation at the bedside. In this study, MP was monitored in ARDS patients, and its correlation with lung ultrasound scores (LUS) was evaluated. Further analysis also explored the value of MP in evaluating the severity and prognosis of ARDS. Methods. A total of 121 patients with moderate to severe ARDS admitted to the intensive care unit (ICU) from June 2017 to April 2020 and treated with invasive mechanical ventilation were sequentially included in this study. Their general information was collected, and MP was recorded at 0 h, 24 h, 48 h, and 72 h after admission to the ICU. Professionally trained researchers performed the LUS assessments. Patients were divided into the death and survival groups according to their 28-day prognosis. The trend of MP and LUS at the four time points was analyzed. A receiver operating characteristic curve (ROC) was used to analyze the predictive value of MP and LUS scores at 0 h and 72 h for the prognosis (28-day mortality rate) of patients with moderate to severe ARDS. Results. 121 patients were included in the analysis, of which 73 were male and 48 were female. When patients entered the ICU, their oxygenation index ( t : 30885, P < 0.01 ), APACHE II score ( t : 2.105, P < 0.05 ), and SOFA score ( t : 4.134, P < 0.001 ) were higher in the death group than the survival group. The death group had significantly higher MP and LUS at each time point (0 h, 24 h, 48 h, and 72 h) compared to the survival group (all P < 0.05 ). There was a significant upward trend over time in the MP and LUS of the death group, contrasting to a significant downward trend in the survival group (all P < 0.05 ). The Pearson correlation analysis showed that MP and LUS were significantly positively correlated at each time point ( r values: 0 h: 0.3027; 24 h: 0.3705; 48 h: 0.3902; 72 h: 0.5916; all P < 0.01 ). The ROC curves showed that MP and LUS at 72 h were of significant value in predicting the prognosis of ARDS patients, with areas under the curve of 0.866 ± 0.032 and 0.839 ± 0.037 , respectively. Conclusion. There was a significant correlation between the MP and LUS of ARDS patients at four time points from 0 to 72 h, which has a clinical value in evaluating severity and prognosis.

Development and validation of a mechanical power-oriented prediction model of weaning failure in mechanically ventilated patients: a retrospective cohort study

“…3 As a comprehensive respiratory mechanics index, MP is a quantitative measure of the energy required to overcome pulmonary resistance and maintain alveolar opening and optimal oxygenation during mechanical ventilation, and can reflect the severity of lung lesions. 34 In this study, we found that larger MP values before weaning were associated with a greater energy load that must be overcome by the respiratory muscles during spontaneous breathing, and a higher the risk of weaning failure, which is consistent with the findings of Ghiani et al 11 In accordance with previous studies, 3 35 the length of ICU stay and duration of IMV were also independent predictors of weaning failure. With a length of stay in ICU >7 days and duration of IMV >3 days, the OR values of the risk of weaning failure increased to 2.43 (95% CI: 1.96 to 3.02) and 2.33 (95% CI: 1.87 to 2.90), respectively, (both p<0.001) (table 2).…”

role of point of care ultrasound in diagnosis of patients with sepsis in comparison with sequential organ failure assessment score in emergency medicine department of Suez Canal University hospital

“…Their findings revealed that at each time point (0 h, 24 h, 48 h, and 72 h), the lung ultrasonography in the death group was higher than in the survival group (all P 0.05). Noting that although the LUS of the survivors showed a significant decline over time, that of the death group showed a significant rise over time (all P 0.05) (14) .…”

Lung ultrasound score and in-hospital mortality of adults with acute respiratory distress syndrome: a meta-analysis

“…Overall, 13 cohort studies, including eight prospective studies [ 15 , 17 , 19 , 20 , 22 – 24 , 26 ] and five retrospective studies [ 14 , 16 , 18 , 21 , 25 ], were analyzed in this meta-analysis. The characteristics of the included studies are summarized in Table 1 .…”