Comparing mini bronchoalveolar lavage and endotracheal aspirate in diagnosing bacterial pneumonia in the intensive care unit

Pneumonia is a major cause of morbidity and mortality among patients in the intensive care unit (ICU). Timely and accurate diagnosis is crucial for effective treatment, but lower respiratory tract sampling techniques vary in sensitivity and specificity. This study aims to compare the diagnostic accuracy of endotracheal aspirate (ETA) with mini bronchoalveolar lavage (mBAL) in detecting bacterial pneumonia in intubated patients, assessing sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ETA against mBAL, the gold standard.

A cross-sectional comparative study was conducted at the ICU of Sindh Institute of Urology and Transplantation (SIUT), Karachi, Pakistan, over 7 months. Adult patients on mechanical ventilation with suspected or confirmed pneumonia were included. Both mBAL and ETA samples were collected under strict aseptic conditions.

Out of 120 patients, 112 paired samples were analyzed. ETA exhibited a sensitivity of 81.1%, specificity of 92.1%, PPV of 95.2%, and NPV of 71.4%, with an overall accuracy of 84.8%. The most commonly isolated pathogens were Acinetobacter and Klebsiella. No serious adverse events occurred.

ETA is a cost-effective and reliable alternative to mBAL for diagnosing bacterial pneumonia in intubated ICU patients, but clinicians should carefully interpret negative results.