Exhaled Breath: A Novel Technique for Rapid Diagnosis of Respiratory Diseases and Infections

The major aim of this observational study is to validate the new technique, Orbitrap and Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry, to sample and analyze exhaled patient breath that may be then used in non-intensive care unit (ICU) environments where rapid virus or other respiratory pathogen detection is of great utility. The ICU permits the direct measure of ventilator-dependent patients with known pulmonary disease (by sputum, chest x-ray, and/or bronchial lavage analysis) together with a simple, pure, and concentrated breath sample (expired air via ventilator tubing) for analysis.

Sub-aim 1: Run patient samples on Orbitrap & MALDI. Proteins in the samples will be captured and analyzed by Orbitrap and MALDI mass spectrometry. Selected proteins will be enzymatically digested into peptides and correlations to existing peptides from previous proteomic studies of exhaled breath condensates (EBC) will be examined. Candidate virus & bacterial proteins, as well as other cellular and biomarkers, will be cataloged.

Sub-aim 2: Correlate collected analyzed sample collection during hospitalization with other hospital data that may have been collected for clinical reasons by the clinical care team, at or around the study time period (+/- 3 days), concerning for the laboratory diagnosis of respiratory disease.

Inclusion criteria

• Non-COVID-19 adult consented patients (>18yo) on ventilatory support in the ICU at OHSU

Exclusion criteria

• Patients with "severe respiratory distress" as defined by arterial pO2 of <60 mmHg on maximal FiO2 & optimal ventilator settings
• Patient with severe hemodynamic instability as defined by (a) receiving IV infusion of 2 or more pressors or inotropic medications (Levophed, vasopressin, phenylephrine, or epinephrine) & (b) MAP of <60 mmHg or SB <80 mmHg