Evaluation of two prototypes for inhalation of nitric oxide during mechanical ventilation with different tidal volumes

Background: Two prototypes for integrated nitric oxide (NO) administration during mechanical ventilation have recently been developed (Servo 300 NO-A prototype, Siemens, Lund, Sweden; NO-domo, Drager AG, Lubeck, Germany). Objectives: To test the accuracy for the administration and the inbuilt electrochemical NO/NO2 measurement of these prototypes. Design: Different NO concentrations (NOin, 0.5-90 ppm) and different tidal volumes (TV, 100-250 ml for paediatric patients, 300-1,000 ml for adult patients) were tested. Both the adjusted NOin as well as the electrochemical measurement were compared to chemiluminescence as the reference method. Results: The mean difference between NOin and chemiluminescence measurements was 0.46±0.72 ppm for the Servo and 0.61±2.01 ppm for the NO-domo. This difference was dependent on TV and NOin. For NOin ≤40 ppm and the adult range of TV, the mean difference was 0.17±0.25 ppm for the Servo and 1.00±0.48 ppm for the NO-domo. The comparison between the electrochemical measureme...