AN EVALUATION OF A NEW ANALYZER FOR INHALED NITRIC-OXIDE ADMINISTRATION

We examined the ability of a new combined nitric oxide (NO)/nitrogen d ioxide (NO2) electrochemical analyser (PrinterNO(x), Micro Medical Lim ited Chatham, Kent, England) to measure NO and NO2 concentrations. The PrinterNO(x) was compared to a chemiluminescence analyser (42H, Therm o Environmental Instruments Inc, Franklin MA, U.S.A.). NO and NO2 were generated in a standard ventilator circuit using a paediatric ventila tor (900C, Siemens Elema, Sweden) connected to an artificial lung (260 li, TTL Test Lung, Michigan Instruments, MI, U.S.A.). Forty-four paire d NO measurements ranging from 2.56 ppm to 74.6 ppm and 50 paired NO2 measurements ranging from 0.0 ppm to 5.39 ppm were obtained. For the m easurement of NO the PrinterNO(x) showed a tendency to overestimate th e chemiluminescence analyser Regression analysis showed a close relati onship between the two analysers with r(2) = 0.9981 and a regression e quation of y = 1.1658 x +0.0197. In the more clinically important rang e of 0-25 ppm, r(2) increased to 0.9996 with a regression equation of y = 1.1984 x -0.4657. Conversely the PrinterNO(x) underestimated the c hemiluminescence analyser for the measurement of NO2. The regression e quation describing this relationship was y = 0.879 x -0.0447 (r(2) = 0 .9993). We conclude that the PrinterNO(x) is of sufficient accuracy to be of clinical use in the administration of NO.