Noninvasive Administration of Inhaled Nitric Oxide and its Hemodynamic Effects in Patients With Acute Right Ventricular Dysfunction

Objective: The authors aimed to assess the hemodynamic effects and demonstrate the feasibility of inhaled nitric oxide (iNO) in hemodynamically unstable patients with acute right ventricular (RV) dysfunction and to explore the safety profile of this approach.

Design: Retrospective cohort study.

Setting: Intensive care unit (ICU) of 2 tertiary care centers between January 2013 and 2017.

Participants: All patients with RV dysfunction in whom iNO was initiated without invasive mechanical ventilation.

Intervention: Noninvasive administration of iNO.

Measurements and main results: Eighteen patients received the intervention during the study period; 8 of these patients had a pulmonary artery catheter and 2 had a pulse contour analysis device. Median (interquartile range) iNO concentration was 20 (20-20) ppm, and therapy duration was 24 (12-46) hours. Most patients received iNO through nasal prongs (66.7%) or a high-flow nasal cannula (27.8%). Within 1 hour, iNO reduced pulmonary vascular resistance from 219.1 to 165.4 dyn•s/cm⁵ (n = 7; p < 0.001), mean pulmonary artery pressure from 28.4 to 25.3 mmHg (n = 8; p = 0.01), and central venous pressure from 17.5 to 13.1 mmHg (n = 16; p = 0.001). Indexed cardiac output increased from 2.0 to 2.6 L/min/m² (n = 9; p = 0.004). ICU mortality was 27.78%, and median ICU length of stay was 7 (5-9) days. Two significant bleeding episodes requiring intervention and 1 acute kidney injury occurred during iNO therapy. No headache was reported.

Conclusion: Noninvasively administered iNO was associated with favorable hemodynamic effects in ICU patients with acute RV dysfunction. These results suggest the safety and feasibility of this therapy for which further prospective study is warranted.