CHANGES IN NOCTURNAL OXIMETRY AFTER TREATMENT OF EXACERBATIONS IN CYSTIC-FIBROSIS

Sleep related arterial oxygen desaturation has been described in clini cally stable young adults with cystic fibrosis. The incidence and seve rity of nocturnal oxygen desaturation in children during infective exa cerbations and the changes that occur with treatment were examined. Fo rty five children with proved cystic fibrosis, median age 8.9 years, a dmitted to the Regional Cystic Fibrosis Unit underwent clinical evalua tion, spirometry, and measurement of peak flow and nocturnal oxygen sa turation on admission and after 10 days' treatment. There was a signif icant improvement in all the above measurements, with the averaged ove rnight saturation changing from a mean (SD) 92.7 (2.7)% to 94.3 (2.0)% , mean (SE) difference 1.58 (0.37). The time spent with a saturation 4 % or more below their clinic value showed a marked improvement from 12 2 (152) minutes on the first night to 21 (30.7) on the second, mean (S E) difference 101 (22.4). Eight young children could not perform pulmo nary function tests, all desaturated on the admission night. Nocturnal hypoxaemia is a common finding in young cystic fibrosis patients duri ng infective exacerbations but improves with treatment. Overnight oxim etry is simple to perform, well tolerated, and identifies patients wit h marked nocturnal desaturation.