Oxygen saturation in cystic fibrosis.

The availability of non-invasive oxygen saturation (SaO2) measurement could prove to be a useful tool for following up the progress of patients with cystic fibrosis. The present study was undertaken to compare its use with other routine measurements in the clinic. A total of 100 patients with cystic fibrosis were compared with 50 patients with stable asthma. The children were aged between 5 and 16 years and were studied as outpatients. A positive correlation was found between forced expiratory volume in one second and SaO2 in the group with cystic fibrosis and in the comparison group. Median SaO2 in those with cystic fibrosis (94.0%) was significantly lower than in controls (97.0%). Significant correlations were also found in the patients with cystic fibrosis for the following: Shwachman-Kulczycki score, higher weight centiles, and chronic pseudomonas lung infection with or without staphylococci. An inverse correlation was found with the Chrispin-Norman chest x ray score. SaO2 measurements are useful in the outpatient assessment of patients with cystic fibrosis and compare well with other standard tests of disease severity.