COVID-19 ARDS Is Characterized by Increased Dead Space Ventilation Compared With Non-COVID ARDS

Area of Science:

• Pulmonary Medicine
• Critical Care Medicine
• Respiratory Physiology

Background:

• Acute Respiratory Distress Syndrome (ARDS) in COVID-19 patients involves pulmonary microcirculatory alterations.
• These alterations may lead to increased dead-space ventilation compared to non-COVID-19 ARDS.

Purpose of the Study:

• To determine if dead-space ventilation differs between COVID-19 ARDS and non-COVID-19 ARDS.
• To compare respiratory system compliance and mechanical ventilation parameters in these patient groups.

Main Methods:

• A comparative study included 187 patients with COVID-19 ARDS and 178 with non-COVID-19 ARDS on invasive mechanical ventilation.
• Data on dead-space ventilation, respiratory compliance, and ventilation settings were collected within 24 hours of ventilation initiation.

Main Results:

• Corrected minute ventilation, a dead-space surrogate, was significantly higher in COVID-19 ARDS (12.6 L/min) versus non-COVID-19 ARDS (9.4 L/min).
• Respiratory system compliance was similar between groups when PEEP was optimized.
• COVID-19 ARDS patients received higher PEEP and lower tidal volumes.

Conclusions:

• Indirect measurements indicate higher dead-space ventilation in COVID-19 ARDS.
• Optimal respiratory system compliance is achievable in both ARDS types with individualized PEEP.
• Mechanical ventilation strategies should be tailored to individual patients, irrespective of ARDS etiology.