Objective: Fiberoptic bronchoscopy (FOB) and bronchoalveolar lavage (BAL) are major tools in the diagnosis of pulmonary complications in immunocompromised patients. Nevertheless, severe hypoxemia is an accepted contraindication to FOE in nonintubated patients. The purpose of this study was to evaluate the feasibility and safety of laryngeal mask airway (LMA)-supported FOE with BAL in immunosuppressed patients with suspected pneumonia and severe hypoxemia. Design: Prospective, clinical investigation. Setting: Medical intensive care unit of a university hospital. Patients: Forty-six immunosuppressed patients admitted to our intensive care unit with suspected pneumonia and Pao(2)/F-102 less than or equal to 125. Interventions: After the administration of 0.3 mg kg(-1) of etomidate, the patients were ventilated manually while receiving 1.0 Re,. After the administration of 2.5 mg kg(-1) of propofol, followed by an infusion of 9.1 +/- 2.3 mg kg(-1) hr(-1) of propofol, the LMA (size 3 or 4) was placed and connected to a bag-valve unit to allow manual ventilation with 1.0 Fo(102). The FOE was introduced through a T-adapter attached to the LMA, and BAL was carried out with 150 mt of sterile 0.9% saline solution by sequential instillation and aspiration of 50-ml aliquots. Measurements and Main Results: Three patients developed transient laryngospasm during passage of the bronchoscope via the LMA, which resolved with deepening of anesthesia. Changes in mean blood pressure, heart rate, Pao(2)/Fo(102), and Pacq Values induced by the procedure did not reach significance. Seven patients (15%) presented hypotension (mean blood pressure, <60 mm Hg) maintained for 120 +/- 40 sees, which required plasma expanders in three cases. Oxygen desaturation to <90% occurred in six patients (13%) during BAL. Nevertheless, the lowest Sao, during the procedure was significantly higher than the initial san, (94% +/- 4% vs. 90% +/- 2%). No patient required tracheal intubation during the 8 hrs after the procedure. BAL had an overall diagnostic yield of 65%, Because of the results obtained by using the BAL analysis, treatment was modified in 33 (72%) cases. Conclusion: Application of the LMA appears to be a safe and effective alternative to intubation for accomplishing FOE with BAL in immunosuppressed patients with suspected pneumonia and severe hypoxemia.