OBJECTIVE The experience of noninvasive positive pressure ventilation (NPPV) in the pediatric setting is limited. The aim of the present study is to retrospectively evaluate the effectiveness of NPPV in pediatric immunocompromised patient admitted in our PICU (Pediatric Intensive Care Unit) for acute respiratory failure. METHODS Retrospective cohort study of children admitted to the PICU of Hospital do Cancer between June 1997 and May 2005 requiring ventilatory support. RESULTS A total of 239 admissions were included. The first mechanical ventilation (MV) technique used was NPPV in 120 (50.2%) patients [noninvasive ventilation (NIV) group] and conventional MV in 119 (49.8%) [invasive ventilation (IV) group]; 25.8% of the patients from the NIV group subsequently required intubation. Patients in the IV group were more likely to be in a severe clinical status. Characteristics associated with severe clinical status were median value for therapeutic intervention scoring system score (37.5 points IV vs. 29 points NIV, P<0.0001), presence of >2 organs failure (63.6% IV vs. 36.4% NIV, P<0.0001), cardiac failure (62.5% IV vs. 37.5% NIV, P<0.0001), and septic shock (63.9% IV vs. 36.1% NIV, P<0.0001). Documented severe pulmonary disease was significantly higher (67.6%) in IV group, P=0.02. Baseline values of arterial pCO2, hypoxemia, arterial pH, and respiratory rate did not differ between the groups. Multivariate analysis showed that independent predictive factors for intubation were solid tumors (P=0.012), cardiovascular dysfunction (P<0.0001), and therapeutic intervention scoring system score >or=40 points (P=0.018). CONCLUSIONS Our results encourage the use of NPPV as a first-line treatment in children with malignancies who develops acute respiratory failure, except in those with severe hemodynamic status.