Comparative efficacy of bronchoalveolar lavage and telescoping plugged catheter in the diagnosis of pneumonia in mechanically ventilated patients

Abstract

The relative efficacy of telescoping plugged catheter (TPC) and bronchoalveolar lavage (BAL) in the diagnosis of pneumonia in mechanically ventilated patients has been compared in 45 subjects suspected of having pneumonia because of the presence of clinical and radiographic criteria. Diagnosis of pneumonia was strongly suggested in 25 of the 45 patients, and definitely confirmed in 10 of them. The diagnostic threshold to assess a quantitative bacterial culture as positive was a growth on BAL of greater-than-or-equal-to 10(5) cfu/ml and on TPC of greater-than-or-equal-to 10(3) cfu/ml. The BAL, specimen cultures established the diagosis in 19 cases (76 percent). In the remaining six patients, this technique did not permit the assessment of the diagnosis, which was established by other procedures (TPC, blood cultures, clinical outcome, or autopsy). False-positive results were not found. Sensitivity and specificity for BAL cultures were 76 percent and 100 percent, respectively. Telescoping plugged catheter established the presence of pneumonia in 16 patients (64 percent). Combining both techniques, the sensitivity increased up to 88 percent, maintaining specificity of 100 percent. In summary, BAL has a greater sensitivity than TPC in the diagnosis of pneumonias in mechanically ventilated patients. However, they are procedures that can complement each other.