INHALED NITRIC-OXIDE IN INFANTS WITH DEVELOPING OR ESTABLISHED CHRONIC LUNG-DISEASE

The effect on gas exchange of increasing concentrations of nitric oxid e (0-60 parts per million) added to the inspired gases of nine ventila tor-dependent infants (median postnatal age = 4 weeks, range 2 - 16 we eks) with chronic lung disease and pathological oxygenation index valu es was studied by means of arterial or transcutaneous PO2/PCO2. A sign ificant improvement of oxygenation, indicated by a reduction of oxygen ation index, was found (p < 0.014). The optimal nitric oxide concentra tion and the individual response varied between patients. PO2 returned to baseline values after the discontinuation of nitric oxide in all p atients except one. No effect on PCO2 could be identified, Methaemoglo bin values only increased marginally during the nitrous oxide expositi on (pre-nitric oxide: 0.56% +/- 0.27; post-nitric oxide: 0.78 +/- 0.08 ; p = ns). Systemic blood pressure and heart rate were unaffected in a ll patients. Before inhaled nitric oxide can be considered for prolong ed use in this patient category further studies regarding long-term ef ficacy and safety are needed.