Prognostication using SpO(2)/FiO(2) in invasively ventilated ICU patients with ARDS due to COVID-19-Insights from the PRoVENT-COVID study

Background: The SpO(2)/FiO(2) is a useful oxygenation parameter with prognostic capacity in patients with ARDS. We investigated the prognostic capacity of SpO(2)/FiO(2) for mortality in patients with ARDS due to COVID-19. Methods: This was a post-hoc analysis of a national multicenter cohort study in invasively ventilated patients with ARDS due to COVID-19. The primary endpoint was 28-day mortality. Results: In 869 invasively ventilated patients, 28-day mortality was 30.1%. The SpO(2)/FiO(2) on day 1 had no prognostic value. The SpO(2)/FiO(2) on day 2 and day 3 had prognostic capacity for death, with the best cut-offs being 179 and 199, respectively. Both SpO(2)/FiO(2) on day 2 (OR, 0.66 [95%-CI 0.46-0.96]) and on day 3 (OR, 0.70 [95%-CI 0.51-0.96]) were associated with 28-day mortality in a model corrected for age, pH, lactate levels and kidney dysfunction (AUROC 0.78 [0.76-0.79]). The measured PaO2/FiO(2) and the PaO2/FiO(2) calculated from SpO(2)/FiO(2) were strongly correlated (Spearman's r = 0.79). Conclusions: In this cohort of patients with ARDS due to COVID-19, the SpO(2)/FiO(2) on day 2 and day 3 are independently associated with and have prognostic capacity for 28-day mortality. The SpO(2)/FiO(2) is a useful metric for risk stratification in invasively ventilated COVID-19 patients. (C) 2021 The Authors. Published by Elsevier Inc

Prognostication using SpO2/FiO2 in invasively ventilated ICU patients with ARDS due to COVID-19 - Insights from the PRoVENT-COVID study

BACKGROUND: The SpO2/FiO2 is a useful oxygenation parameter with prognostic capacity in patients with ARDS. We investigated the prognostic capacity of SpO2/FiO2 for mortality in patients with ARDS due to COVID-19. METHODS: This was a post-hoc analysis of a national multicenter cohort study in invasively ventilated patients with ARDS due to COVID-19. The primary endpoint was 28-day mortality. RESULTS: In 869 invasively ventilated patients, 28-day mortality was 30.1%. The SpO2/FiO2 on day 1 had no prognostic value. The SpO2/FiO2 on day 2 and day 3 had prognostic capacity for death, with the best cut-offs being 179 and 199, respectively. Both SpO2/FiO2 on day 2 (OR, 0.66 [95%-CI 0.46-0.96]) and on day 3 (OR, 0.70 [95%-CI 0.51-0.96]) were associated with 28-day mortality in a model corrected for age, pH, lactate levels and kidney dysfunction (AUROC 0.78 [0.76-0.79]). The measured PaO2/FiO2 and the PaO2/FiO2 calculated from SpO2/FiO2 were strongly correlated (Spearman's r = 0.79). CONCLUSIONS: In this cohort of patients with ARDS due to COVID-19, the SpO2/FiO2 on day 2 and day 3 are independently associated with and have prognostic capacity for 28-day mortality. The SpO2/FiO2 is a useful metric for risk stratification in invasively ventilated COVID-19 patients

Associations between changes in oxygenation, dead space and driving pressure induced by the first prone position session and mortality in patients with acute respiratory distress syndrome

Background: Outcome prediction in acute respiratory distress syndrome (ARDS) is challenging, especially in patients with severe hypoxemia. The aim of the current study was to determine the prognostic capacity of changes in PaO2/FiO2, dead space fraction (VD/VT) and respiratory system driving pressure (ΔPRS) induced by the first prone position (PP) session in patients with ARDS. Methods: This was a post hoc analysis of the conveniently-sized 'Molecular Diagnosis and Risk Stratification of Sepsis' study (MARS). The current analysis included ARDS patients who were placed in the PP. The primary endpoint was the prognostic capacity of the PP-induced changes in PaO2/FiO2, VD/VT, and ΔPRS for 28-day mortality. PaO2/FiO2, VD/VT, and ΔPRS was calculated using variables obtained in the supine position before and after completion of the first PP session. Receiving operator characteristic curves (ROC) were constructed, and sensitivity, specificity positive and negative predictive value were calculated based on the best cutoffs. Results: Ninety patients were included; 28-day mortality was 46%. PP-induced changes in PaO2/FiO2 and VD/VT were similar between survivors vs. non-survivors [+83 (+24 to +137) vs. +58 (+21 to +113) mmHg, and -0.06 (-0.17 to +0.05) vs. -0.08 (-0.16 to +0.08), respectively]. PP-induced changes in ΔPRS were different between survivors vs. non-survivors [-3 (-7 to 2) vs. 0 (-3 to +3) cmH2O; P=0.03]. The area under the ROC of PP-induced changes in ΔPRS for mortality, however, was low [0.63 (95% confidence interval (CI), 0.50 to 0.75]; PP-induced changes in ΔPRS had a sensitivity and specificity of 76% and 56%, and a positive and negative predictive value of 60% and 73%. Conclusions: Changes in PaO2/FiO2, VD/VT, and ΔPRS induced by the first PP session have poor prognostic capacities for 28-day mortality in ARDS patients

Closed-Loop ventilation using sidestream versus mainstream capnography for automated adjustments of minute ventilation-A randomized clinical trial in cardiac surgery patients.

BackgroundINTELLiVENT-Adaptive Support Ventilation (ASV) is a closed-loop ventilation mode that uses capnography to adjust tidal volume (VT) and respiratory rate according to a user-set end-tidal CO2 (etCO2) target range. We compared sidestream versus mainstream capnography with this ventilation mode with respect to the quality of breathing in patients after cardiac surgery.MethodsSingle-center, single-blinded, non-inferiority, randomized clinical trial in adult patients scheduled for elective cardiac surgery that were expected to receive at least two hours of postoperative ventilation in the ICU. Patients were randomized 1:1 to closed-loop ventilation with sidestream or mainstream capnography. Each breath was classified into a zone based on the measured VT, maximum airway pressure, etCO2 and pulse oximetry. The primary outcome was the proportion of breaths spent in a predefined 'optimal' zone of ventilation during the first three hours of postoperative ventilation, with a non-inferiority margin for the difference in the proportions set at -20%. Secondary endpoints included the proportion of breaths in predefined 'acceptable' and 'critical' zones of ventilation, and the proportion of breaths with hypoxemia.ResultsOf 80 randomized subjects, 78 were included in the intention-to-treat analysis. We could not confirm the non-inferiority of closed-loop ventilation using sidestream with respect to the proportion of breaths in the 'optimal' zone (mean ratio 0.87 [0.77 to ∞]; P = 0.116 for non-inferiority). The proportion of breaths with hypoxemia was higher in the sidestream capnography group versus the mainstream capnography group.ConclusionsWe could not confirm that INTELLiVENT-ASV using sidestream capnography is non-inferior to INTELLiVENT-ASV using mainstream capnography with respect to the quality of breathing in subjects receiving postoperative ventilation after cardiac surgery.Trial registrationNCT04599491 (clinicaltrials.gov)

MOESM1 of Risk stratification using SpO2/FiO2 and PEEP at initial ARDS diagnosis and after 24Â h in patients with moderate or severe ARDS

Additional file 1. SF and PEEP in ARDS_Electronic Supplementary Material

Table of contents

Table of contents. In: Perspectives chinoises, n°3, 1992. p. 43

Risk stratification using SpO2/FiO2 and PEEP at initial ARDS diagnosis and after 24 h in patients with moderate or severe ARDS

Background: We assessed the potential of risk stratification of ARDS patients using SpO2/FiO2 and positive end-expiratory pressure (PEEP) at ARDS onset and after 24 h. Methods: We used data from a prospective observational study in patients admitted to a mixed medical–surgical intensive care unit of a university hospital in the Netherlands. Risk stratification was by cutoffs for SpO2/FiO2 and PEEP. The primary outcome was in-hospital mortality. Patients with moderate or severe ARDS with a length of stay of > 24 h were included in this study. Patients were assigned to four predefined risk groups: group I (SpO2/FiO2 ≥ 190 and PEEP < 10 cm H2O), group II (SpO2/FiO2 ≥ 190 and PEEP ≥ 10 cm), group III (SpO2/FiO2 < 190 and PEEP < 10 cm H2O) and group IV (SpO2/FiO2 < 190 and PEEP ≥ 10 cm H2O). Results: The analysis included 456 patients. SpO2/FiO2 and PaO2/FiO2 had a strong relationship (P < 0.001, R2 = 0.676) that could be described in a linear regression equation (SpO2/FiO2 = 42.6 + 1.0 * PaO2/FiO2). Risk stratification at initial ARDS diagnosis resulted in groups that had no differences in in-hospital mortality. Risk stratification at 24 h resulted in groups with increasing mortality rates. The association between group assignment at 24 h and outcome was confounded by several factors, including APACHE IV scores, arterial pH and plasma lactate levels, and vasopressor therapy. Conclusions: In this cohort of patients with moderate or severe ARDS, SpO2/FiO2 and PaO2/FiO2 have a strong linear relationship. In contrast to risk stratification at initial ARDS diagnosis, risk stratification using SpO2/FiO2 and PEEP after 24 h resulted in groups with worsening outcomes. Risk stratification using SpO2/FiO2 and PEEP could be practical, especially in resource-limited settings

Risk stratification using SpO2/FiO2and PEEP at initial ARDS diagnosis and after 24Â h in patients with moderate or severe ARDS

Background: We assessed the potential of risk stratification of ARDS patients using SpO2/FiO2and positive end-expiratory pressure (PEEP) at ARDS onset and after 24 h. Methods: We used data from a prospective observational study in patients admitted to a mixed medicalâ\u80\u93surgical intensive care unit of a university hospital in the Netherlands. Risk stratification was by cutoffs for SpO2/FiO2and PEEP. The primary outcome was in-hospital mortality. Patients with moderate or severe ARDS with a length of stay of > 24 h were included in this study. Patients were assigned to four predefined risk groups: group I (SpO2/FiO2 â\u89¥Â 190 and PEEP < 10 cm H2O), group II (SpO2/FiO2 â\u89¥Â 190 and PEEP â\u89¥Â 10 cm), group III (SpO2/FiO2 < 190 and PEEP < 10 cm H2O) and group IV (SpO2/FiO2 < 190 and PEEP â\u89¥Â 10 cm H2O). Results: The analysis included 456 patients. SpO2/FiO2and PaO2/FiO2had a strong relationship (P < 0.001, R2 = 0.676) that could be described in a linear regression equation (SpO2/FiO2 = 42.6 + 1.0 * PaO2/FiO2). Risk stratification at initial ARDS diagnosis resulted in groups that had no differences in in-hospital mortality. Risk stratification at 24 h resulted in groups with increasing mortality rates. The association between group assignment at 24 h and outcome was confounded by several factors, including APACHE IV scores, arterial pH and plasma lactate levels, and vasopressor therapy. Conclusions: In this cohort of patients with moderate or severe ARDS, SpO2/FiO2and PaO2/FiO2have a strong linear relationship. In contrast to risk stratification at initial ARDS diagnosis, risk stratification using SpO2/FiO2and PEEP after 24 h resulted in groups with worsening outcomes. Risk stratification using SpO2/FiO2and PEEP could be practical, especially in resource-limited settings

Ventilation management and clinical outcomes in invasively ventilated patients with COVID-19 (PRoVENT-COVID): a national, multicentre, observational cohort study

Background: Little is known about the practice of ventilation management in patients with COVID-19. We aimed to describe the practice of ventilation management and to establish outcomes in invasively ventilated patients with COVID-19 in a single country during the first month of the outbreak. Methods: PRoVENT-COVID is a national, multicentre, retrospective observational study done at 18 intensive care units (ICUs) in the Netherlands. Consecutive patients aged at least 18 years were eligible for participation if they had received invasive ventilation for COVID-19 at a participating ICU during the first month of the national outbreak in the Netherlands. The primary outcome was a combination of ventilator variables and parameters over the first 4 calendar days of ventilation: tidal volume, positive end-expiratory pressure (PEEP), respiratory system compliance, and driving pressure. Secondary outcomes included the use of adjunctive treatments for refractory hypoxaemia and ICU complications. Patient-centred outcomes were ventilator-free days at day 28, duration of ventilation, duration of ICU and hospital stay, and mortality. PRoVENT-COVID is registered at ClinicalTrials.gov (NCT04346342). Findings: Between March 1 and April 1, 2020, 553 patients were included in the study. Median tidal volume was 6·3 mL/kg predicted bodyweight (IQR 5·7–7·1), PEEP was 14·0 cm H2O (IQR 11·0–15·0), and driving pressure was 14·0 cm H2O (11·2–16·0). Median respiratory system compliance was 31·9 mL/cm H2O (26·0–39·9). Of the adjunctive treatments for refractory hypoxaemia, prone positioning was most often used in the first 4 days of ventilation (283 [53%] of 530 patients). The median number of ventilator-free days at day 28 was 0 (IQR 0–15); 186 (35%) of 530 patients had died by day 28. Predictors of 28-day mortality were gender, age, tidal volume, respiratory system compliance, arterial pH, and heart rate on the first day of invasive ventilation. Interpretation: In patients with COVID-19 who were invasively ventilated during the first month of the outbreak in the Netherlands, lung-protective ventilation with low tidal volume and low driving pressure was broadly applied and prone positioning was often used. The applied PEEP varied widely, despite an invariably low respiratory system compliance. The findings of this national study provide a basis for new hypotheses and sample size calculations for future trials of invasive ventilation for COVID-19. These data could also help in the interpretation of findings from other studies of ventilation practice and outcomes in invasively ventilated patients with COVID-19. Funding: Amsterdam University Medical Centers, location Academic Medical Center