PROTECTED BRONCHOALVEOLAR LAVAGE IN THE DIAGNOSIS OF VENTILATOR-ASSOCIATED PNEUMONIA

The aim of this study was to evaluate the diagnostic efficacy of prote cted bronchoalveolar lavage (PBAL) in ventilator-associated pneumonia (VAP), and to determine the effect of antibiotic therapy on its microb iological and cytological results. We prospectively studied 102 episod es of suspected VAP in 93 patients, Subsequent follow-up confirmed VAP in 35 of the 102 (34%) cases, In 55 of the 102 (55%) VAP was ruled ou t, and the diagnosis remained undetermined in 12 of the 102 (12%) epis odes. In the VAP group, 30 of the 35 (86%) PBAL (>10(4) colony-forming units (cfu). mL(-1)) cultures were positive, In the non-VAP group, 5 of the 55 (9%) PBAL cultures were positive, A Giemsa stain of PBAL sam ples was performed in 32 of the 35 cases of VAP, Intracellular organis ms (ICO) were found in 24 of the 32 (75%) cases, Seven of the other ei ght cases without evidence of ICO were already on antibiotics, In the non-VAP group, ICO were present in only 1 out of 55 (2%) cases, The me an ICO was significantly higher in the group who had not received anti biotics when compared with those patients previously treated for less than 48 h (p less than or equal to 0.01) and those treated for more th an 48 h (p=0.009). The sensitivity of protected bronchoalveolar lavage quantitative cultures was 87% and the specificity 91%. The sensitivit y of cytological analysis for intracellular organisms was 75% and the specificity 98%, According to our results, if the patient is already o n antibiotics, the direct examination of protected bronchoalveolar lav age fluid is less reliable, although still helpful.