THE SAFETY AND DIAGNOSTIC-ACCURACY OF MINIBRONCHOALVEOLAR LAVAGE IN PATIENTS WITH SUSPECTED VENTILATOR-ASSOCIATED PNEUMONIA

Objectives: To assess the safety of minibronchoalveolar lavage done by respiratory therapists for the evaluation of suspected ventilator-ass ociated pneumonia and to determine the diagnostic agreement between qu antitative lower airway cultures obtained by the minibronchoalveolar l avage and protected specimen brush techniques. Design: A prospective d irect comparison of two diagnostic techniques. Setting: An academic te rtiary care center in St. Louis, Missouri. Patients: 72 consecutive pa tients suspected of having ventilator-associated pneumonia on the basi s of clinical evidence. Interventions: Sampling of lower airway secret ions using the protected specimen brush and minibronchoalveolar lavage techniques. Main Outcome Measures: Clinical complications and quantit ative cultures of respiratory secretions. Results: 72 patients suspect ed of having ventilator-associated pneumonia (first episode) were eval uated using minibronchoalveolar lavage. In 42 patients, lower airway s ecretions were also obtained using the protected specimen brush techni que. No change in arterial blood oxygen saturation or heart rate occur red after minibronchoalveolar ravage (P > 0.2). Mean arterial pressure slightly increased with minibronchoalveolar lavage (baseline mean pre ssure, 90.1 mm Hg [CI, 88.4 to 91.7 mm Hg]; average within-person chan ge, 2.6 mm Hg; P = 0.024). Good diagnostic agreement was shown for qua ntitative cultures obtained with the protected specimen brush and mini bronchoalveolar ravage techniques (kappa statistic, 0.63; concordance, 83.3%); 10(3) colony forming units/mL was used as the threshold for a clinically significant culture result. Conclusions: Minibronchoalveol ar ravage is a safe and technically simple procedure for obtaining qua ntitative lower airway cultures in patients requiring mechanical venti lation. Quantitative culture results obtained by minibronchoalveolar r avage are similar to those obtained by the protected specimen brush te chnique.