Abstract
Inhaled nitric oxide (iNO) has been reported as a rescue strategy in ARDS. A potential role for iNO is proposed in COVID-19, especially given the ‘pulmonary vascular’ phenotype and right ventricular (RV) dysfunction increasingly apparent in this disease.
Patients admitted to a tertiary respiratory failure centre in the UK receiving iNO with at least moderate ARDS in March-May 2020 were studied. Measurements to calculate PaO2/FiO2 ratio, oxygenation index (OI), and dead space fraction (based on the Bohr equation) were obtained before and after initiating iNO from ventilator data.
Thirty-five consecutive patients (20% female) were treated with 20 ppm iNO, for 146.4 (80.8) h. PaO2/FiO2 ratio increased from baseline (13.6 [3.9] vs 17.4 [5.5] kPa at 24 hours, p<0.001). OI and dead space fraction were significantly reduced (Figure 1).
According to a pre-defined improvement in PaO2/FiO2 ratio by at least 1.33 kPa, 23 patients [65.7%] responded to iNO at 24 h. Responders had higher baseline brain natriuretic peptide (p=0.023) and troponin (p=0.015).
The 30 day mortality after starting iNO was 17/35 (48.5%).
In this cohort of patients with at least moderately severe COVID-ARDS, iNO at 20 ppm improved oxygenation and ventilatory efficiency. We were able to differentiate responders from non-responders on the basis of higher levels of cardiac biomarkers, suggesting a putative mechanism.
Footnotes
Cite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA3325.
This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2021