Objective. Our objective was to compare the results of a blind lavage vs a bronchoscopic-guided bronchoalveolar lavage for the etiologic diagnosis of ventilator-associated pneumonia (VAP). Design. Prospective study in consecutive patients with high probability of VAP. Every patient underwent both procedures, in a formally randomized fashion. The interpretation of quantitative cultures was done in a blind fashion. Setting. Single center study, with a 20 bed medical and surgical Intensive Care Unit of the University Hospital in Monterrey, Mexico. Patients. Twenty-five patients with high probability of VAP. Interventions. Every patient underwent blind bronchoalveolar lavage with a modified nasogastric tube, and a bronchospic-guided bronchoalveolar lavage. Results. Twenty-one patients underwent both procedures. Four patients were excluded due to contamination of the cultures. The quantitative cultures were compared in a paired fashion. Only two patients had discordant cultures. The correlation coefficient between the number of colonies was very high, r = 0.90 (95% confidence interval [CI], 0.77-0.96; p = 0.0001). Conclusions. The blind bronchoalveolar lavage with a modified nasogastric tube is a valuable tool for the identification of etiologic agent in VAP, particularly when trained bronchoscopists or the necessary resources for bronchoscopic-guided bronchoalveolar lavage are not readily available.