Elsevier

Journal of Critical Care

Volume 71, October 2022, 154021
Journal of Critical Care

Clinical characteristics, respiratory management, and determinants of oxygenation in COVID-19 ARDS: A prospective cohort study

https://doi.org/10.1016/j.jcrc.2022.154021Get rights and content

Highlights

  • Hypoxemia in COVID-19 ARDS is associated with disease severity and comorbidities.

  • Hypoxemia was related to PEEP level, increased deadspace, and d-dimer.

  • Obesity and previous respiratory disease were also independent determinants.

  • Respiratory-system compliance had a unimodal distribution, as in “classical” ARDS.

  • The Berlin definition adequately reflected COVID-19 ARDS severity and prognosis.

Abstract

Purpose

To identify determinants of oxygenation over time in patients with COVID-19 acute respiratory distress syndrome (ARDS); and to analyze their characteristics according to Berlin definition categories.

Materials and methods

Prospective cohort study including consecutive mechanically ventilated patients admitted between 3/20/2020–10/31/2020 with ARDS. Epidemiological and clinical data on admission; outcomes; ventilation, respiratory mechanics and oxygenation variables were registered on days 1, 3 and 7 for the entire population and for ARDS categories.

Results

1525 patients aged 61 ± 13, 69% male, met ARDS criteria; most frequent comorbidities were obesity, hypertension, diabetes and respiratory disease. On admission, 331(21%), 849(56%) and 345(23%) patients had mild, moderate and severe ARDS; all received lung-protective ventilation (mean tidal volumes between 6.3 and 6.7 mL/kg PBW) and intermediate PEEP levels (10–11 cmH2O). PaO2/FiO2, plateau pressure, static compliance, driving pressure, ventilation ratio, pH and D-dimer >2 mg/L remained significantly different among the ARDS categories over time. In-hospital mortality was, respectively, 55%, 58% and 70% (p < 0.000). Independent predictors of changes of PaO2/FiO2 over time were BMI; preexistent respiratory disease; D-dimer >2 mg/L; day 1-PEEP, and day 1-ventilatory ratio.

Conclusion

Hypoxemia in patients with COVID-19-related ARDS is associated with comorbidities, deadspace and activated coagulation markers, and disease severity—reflected by the PEEP level required.

Keywords

COVID-19
ARDS
Mechanical ventilation
Ventilatory ratio
Obesity
BMI

Abbreviations

ARDS
acute respiratory distress PaO2FiO2 syndrome
COVID-19
coronavirus disease 2019
BMI
Body mass index
PBW
predicted body weight
PEEP
positive end-expiratory pressure
ICU
Intensive Care Unit
HFNC
high-flow nasal cannula
NIV
noninvasive mechanical ventilation
APACHE II
Acute Physiologic and Chronic Health Evaluation
SOFA
Sequential Organ Failure Assessment
Vt
tidal volume
CXR
Chest X-ray
CT scan
Computed Tomography scan
RASS
Richmond Agitation Sedation Scale
ACE inhibitors
Angiotensin converting enzyme inhibitors
LDH
lactate dehydrogenase
Vd/Vt
dead space fraction

Cited by (0)

1

The complete list of investigators of the SATI-COVID-19 Study Group is included in Online Data Supplement.

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