objectives: To identify pulmonary risk factors associated with prolonged ICU stay in young children (less than or equal to 2 years) undergoing surgical I repair for congenital heart disease (CHD), Design: Retrospective case series analysis. Setting: Tertialy-care facility, Patients: Clinical records of 134 consecutive, patients aged less than or equal to 2 years undergoing cardiac surgery for CHD were reviewed, and 37 were excluded according to inclusion criteria. Thus, 97 patients were allocated to two groups based on the duration of ICU stay: less than or equal to 7 dais (group 1, n = 57), and > 7 days (group 2, n = 40), Results: Mean ICU duration for groups 1 and 2 was 3.0 +/- 0.4 days and 28.1 +/- 4.4 days, respectively (p < 0,001), In group 1, there were three extubation failures, whereas 11 extubation failures occurred in group 2 (p < 0,0.0001), A total of 22 patients (4 in group 1 and 18 in gl group 2) developed noninfectious pulmonary complications, such as airway, problems, including extrinsic airway compression and tracheobronchomal, (n = 6); pulmonary hypertension (n = 5); phrenic nerve palsy (n = 7); and pleural effusion (n = 8), These 22 patients (23%) contributed to the majority of total ventilator days (67%) as well as ICU stay (61%). Conclusions: Pulmonary complications in general, and central airway problems in particular, are a frequent cause for delayed recovery following cardiac surgery in young children.