Ventilatory Efficiency in Critically Ill COVID-19 Patients

Summary

The new severe acute respiratory syndrome coronavirus 2019 (SARS-CoV-2) causes the illness named COVID-19, which is primarily characterized by pneumonia. As of 27 December, there have been over 79.2 million cases and over 1.7 million deaths reported since the start of the pandemic. In many cases, pneumonia evolves to acute respiratory distress syndrome (ARDS) with the need for mechanical ventilation and patient admission to intensive care unit, determining a marked increase in the need for intensive care beds worldwide.

Pulmonary involvement causes predominantly hypoxemic respiratory failure. Although COVID-19 pneumonia often falls within the diagnostic criteria of ARDS, it differs from it for some peculiar pathophysiological characteristics. In particular, patients with ARDS secondary to COVID-19 often have the compliance of the respiratory system within the normal range. A significant role in the pathophysiology of hypoxemia seems to depend on vascular alterations such as altered pulmonary vascular self-regulation, pulmonary capillary leakage, and microvascular thrombosis in a complex process known as "immunothrombosis". All together they act by altering the relationship between ventilation and perfusion and increasing the dead space, which ultimately results in impaired efficiency of the pulmonary ventilation. Among the various markers associated with the prognosis of patients with COVID-19, D-dimer is linked to both the inflammatory state and thrombotic phenomena and could help to identify patients at greater risk of developing early ventilation-perfusion changes.

This study aims at measuring the ventilatory efficiency, assessed by Ventilatory Ratio, in critically ill, mechanically ventilated, COVID-19 patients and its correlation with plasma D-dimer and quasi-static respiratory compliance.

Conditions

• ARDS

Interventions

OTHER

data collecting

Within 24h from ICU admission, the ventilatory efficiency will be assessed by the following Ventilatory Ratio equation: Ventilatory Ratio = \[minute ventilation (ml/min) × PaCO2 (mm Hg)\]/(predicted body weight × 100 × 37.5). Where PaCO2 is the partial pressure of carbon dioxide in mmHg in the arterial blood. Tha quasi-static compliance will be calculated according to the equation: C=Tidal Volume/(Paw plateau - PEEP total) where Paw plateau is the airway pressure measured during 4 seconds of inspiratory pause, PEEP total is the airway pressure measured during 4 seconds of expiratory pause. In the same time frame, complete blood count, d-dimer, sequential organ failure assessment score, blood gas analysis, haemodynamic and ventilatory parameters will be collected.

Sponsors & Collaborators

• Ospedale Infermi Rimini

  collaborator UNKNOWN

• S. Anna Hospital

  collaborator OTHER

• Azienda Ospedaliero, Universitaria Ospedali Riuniti

  collaborator OTHER

• ASST Fatebenefratelli Sacco

  lead OTHER

Principal Investigators

• Riccardo Colombo, M.D. · ASST Fatebenefratelli Sacco - Ospedale Luigi Sacco

Eligibility

Min Age

18 Years

Max Age

90 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2020-09-01

Primary Completion

2021-03-31

Completion

2021-04-15

Countries

• Italy

Study Locations