Nasal continuous positive airway pressure (N-CPAP), applied immediately after extubation, was prospectively evaluated in 18 neonates recovering from respiratory distress syndrome. Patients were randomly assigned to N-CPAP (group 1, N=9) or a control group given oxygen by hood (group 2, N=9). Groups were comparable in birth weight and duration of intubation. In the 24-hour period following extubation, group 1 showed a significantly lower mean respiratory rate (46 +/- 2 vs 74 +/- 4), alveolar-arterial oxygen gradient (94 +/- 9 vs 134 +/- 12 mm Hg), PCO2 (45 +/- 1 vs 50 +/- 1 mm Hg), higher pH (7.33 +/- 0.01 vs 7.30 +/- 0.01), and less atelectasis by roentgenographic scores. This was associated with considerably better clinical courses in group 1 when compared with group 2, in which six patients required a late trial of N-CPAP because of respiratory deterioration and two patients needed reintubation. Postextubation N-CPAP has a striking beneficial effect on respiratory function and prevention of atelectasis.