High-dose inhaled nitric oxide therapy for nosocomial pneumonia following cardiac surgical procedures
Authors: Kalashnikova T. P. , Kamenshchikov N. O. , Podoksenov Yu. K. , Arseneva Yu. A. , Tyo M. A. , Churilina E. A. , Svirko Yu. S. , Avdeev S. N. , Kozlov B. N. , Boshchenko A. A. 
Published: February 2025

Nosocomial pneumonia is the most common infectious complication following cardiac surgical procedures. The aim was to assess the efficacy and safety of repeated inhalation sessions of 200 ppm nitric oxide for nosocomial pneumonia following cardiac surgical procedures. Methods. The pilot single-center prospective randomized study included spontaneously breathing patients with cardiovascular diseases, operated on under artificial circulation, with a complicated postoperative period in the form of nosocomial pneumonia. These patients (n = 40) underwent surgical procedures under cardiopulmonary bypass and developed nosocomial pneumonia in the postoperative period. The control group (n = 20) received standard antibacterial therapy, the experimental group (n = 20) received additional inhalation of 200 ppm nitric oxide (iNO) for 30 minutes 3 times a day before the completion of antibacterial therapy, but no more than 7 days later. We assessed the duration of antibacterial therapy, the changes in temperature, blood pressure, respiratory rate and heart rate, the oxygenation index SpO2/FiO2 and PO2/FiO2, the level of leukocytes, C-reactive protein, procalcitonin, presepsin, ferritin, and the quality of life questionnaire EQ-5D-5L score. The frequency of changes in antibacterial therapy regimens due to their ineffectiveness and the duration of hospitalization were compared. Results. iNO therapy was well tolerated, did not have a significant effect on systemic hemodynamics, and was not accompanied by a clinically significant increase in the level of methemoglobin and NO2. Its duration was 6.2 ± 0.8 days. In the iNO treatment group, there was a shorter time of antibacterial therapy (p < 0.001), a shorter duration of fever (p = 0,008), and a shorter frequency of changing antibacterial treatment regimens due to their ineffectiveness (p < 0,001). Under the influence of iNO, higher rates of oxygenation indices SpO2/FiO2 were noted on Day 3 (p = 0,034) and on the day of completion of antibacterial therapy (p = 0,009); higher PO2/FiO2 were observed on Day 3 (p = 0,002), Day 5 (p < 0,001) of the therapy and the day of the completion of antibacterial therapy (p = 0,004). In the iNO treatment group, a decrease in the level of leukocytes, procalcitonin, and the neutrophil-to-lymphocyte ratio was detected on Day 3 of the treatment, as well as lower neutrophil levels in the blood on the day of the completion of antibacterial therapy in comparison with the control group. Conclusion. iNO at a dose of 200 ppm 3 times a day in patients with nosocomial pneumonia following cardiac surgical procedures is safe, leads to a reduction in the duration of antibacterial therapy, a decrease in the frequency of changes in antibacterial therapy regimens, the improvement of oxygenation, and faster changes in the laboratory markers of inflammation. The data obtained serve as a prerequisite for the use of iNO for the treatment of nosocomial pneumonia in cardiac surgical patients.