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

Abstract

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). FindingsBetween 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 H 2 O (IQR 11•0-15•0), and driving pressure was 14•0 cm H 2 O (11•2-16•0). Median respiratory system compliance was 31•9 mL/cm H 2 O (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.

Mechanical ventilation parameters in critically ill COVID-19 patients: a scoping review

“…The final selection included 26 studies: 4 multicenter prospective cohort studies [17][18][19][20], 6 multicenter retrospective cohort studies [8,[21][22][23][24][25], 1 single center prospective cohort study [26], 1 multicenter prospective case series [27], 2 multicenter retrospective case series [28,29], 4 single center prospective case series [30][31][32][33] and 8 single center retrospective case series [34][35][36][37][38][39][40][41] (Fig. 1).…”

“…It was also suggested that the mechanical ventilation of patients classified to these two clinical types of disease should also differ; those with stiff lungs should be ventilated in accordance with the recommendations for ARDS, and those with compliant lungs may be ventilated with higher tidal volumes (7-9 ml/kg ideal body weight) and lower PEEP (< 10 cmH 2 O) than recommended [49]. Subsequent studies conducted in larger patient populations did not confirm this observation [17,19,20,23,26]. Our review of the available literature, limited as it is to pooled data from multiple studies with different methodologies, also does not support the existence of a clinical dichotomy.…”

“…Mode of ventilation: The mode of ventilation was reported in 5/26 studies. In four of them the choice was volume-controlled ventilation [18,26,31,36] while in the fifth study pressure-controlled ventilation was used in 52% and volume-controlled ventilation in 19% of the cases [23]. Tidal volume: TV was reported in 13/26 studies.…”

Pathophysiology of COVID-19-associated acute respiratory distress syndrome – Authors' reply

“…Thus, one cannot discriminate COVID-19 ARDS from classical ARDS on the basis of values of compliance. Moreover, studies now totalling well over 1000 patients with COVID-19 ARDS report values of compliance (27 mL/cm H 2 O, 1 35 mL/cm H 2 O, 2 28 mL/cm H 2 O, 3 and 32 mL/cm H 2 O 4 ) that are consistent or even lower than the values observed by Chiumello and colleagues (48 mL/cm H 2 O [SD 16] and 42 mL/cm H 2 O [14]) 5 , 6 and Gattinoni and colleagues (44 mL/cm H 2 O [17]) 7 in classical ARDS. In addition, Panwar and colleagues recently showed that patients with classical ARDS had a wide range of compliance, with about one in eight patients (136 [12·2%] of 1117 patients) having compliance of at least 50 mL/cm H 2 O, and that the ratio of partial pressure of arterial oxygen to fractional concentration of oxygen in inspired air (PaO 2 /FiO 2 ) and static compliance were almost completely dissociated.…”

The COVID‐19 insidious trick: Subjective perception of numbers

“…While it is true that this low infection fatality should reassure people that most infected individuals do not die, it should not be confused as a confirmation of a subjective impression (eg, possibly arising in people outside hospitals that only see asymptomatic/mildly symptomatic cases) that there is not an emergency and that individuals may soften the adoption of the necessary prevention and control measures to interrupt the spread of the disease. Indeed, if only a small percentage of patients are at risk of dying and require hospital care but many are infected in a very short window of time, the absolute number of those requiring admission may rapidly surpass the hospitals and intensive care units bed capacity, reducing quality of care and increasing fatality in patients with severe disease presentation (change of denominator), reaching values higher than 25%‐30% in intensive care units 9‐11 . This impression of a constantly severe disease may be the one of healthcare personnel caring for hospitalized COVID‐19 patients in highly affected areas, who everyday see several patients worsening and requiring invasive mechanical ventilation.…”