The role of quantitative cultures of non-bronchoscopic samples in ventilator associated pneumonia

Abstract

Purpose: The objective of this study is to determine the role of quantitative cultures of non-bronchoscopic samples such as blinded bronchial sampling (BBS) and endotracheal aspirates (ETA) in the management of ventilator associated pneumonia (VAP). The study also evaluates the clinical diagnosis of VAP based on the inclusion of Gram stain results of BBS/ETA samples into modified clinical pulmonary infection score (CPIS). Methods: Fifteen out of the 120 patients admitted to respiratory intensive care unit under mechanical ventilation for more than 48 hours with a clinical suspicion of VAP, were included in this study. Quantitative cultures of BBS and ETA were performed from all the 15 patients. Results: VAP was confirmed in 11 out of 15 cases by quantitative cultures of either the BBS or ETA samples. The condition of 8/11 VAP confirmed patients improved significantly with the change in antibiotic therapy. The overall mortality rate was found to be 18%. The agreement between BBS and ETA results was found to be 83.3%. Modified-clinical pulmonary infection score (CPIS) increased significantly when Gram stain results of BBS/ETA samples were included, thereby strengthening the clinical diagnosis of VAP. Conclusions: Quantitative culture of lower respiratory tract samples obtained by non-bronchoscopic methods may be a useful alternative to bronchoscopy, in the diagnosis of VAP. Inclusion of Gram stain results of BBS/ETA into modified-CPIS may augment the diagnostic evaluation of VAP. Key words: Quantitative cultures, blinded bronchial sampling, clinical pulmonary Infection score, ventilator associated pneumoniaVentilator-associated pneumsonia (VAP), an important form endotracheal aspirates or samples collected either of hospital acquired pneumonia (HAP), specifically refers to bronchoscopically or non-bronchoscopically.2 At the present pneumonia developing in a mechanically ventilated patient time, bronchoscopic sampling of the lower airways, using more than 48 hours after tracheal intubation or tracheostomy. either a protected specimen brush (PSB) or bronchoalveolar VAP continues to complicate the course of patients receiving lavage (BAL) is accepted as the most accurate method of mechanical ventilation in spite of major advances in diagnosing VAP, short of direct tissue examination. However, techniques for its diagnosis and treatment. VAP requires a bronschoscopy is not readily available in many settings and rapid diagnosis and initiation of the appropriate antibiotic there is a growing need to evaluate other sampling techniques treatment since many studies have shown the adverse effect for collecting respiratory secretions. The collection of blind, of inadequate antibiotic treatment on the patients' prognosis. 1 non-bronchoscopic samples is an appealing alternative. Blind sampling can be done by BAL, PSB, or a blind bronchial Detection of the causative organism is crucial for the suction sample (BBS) can be taken.3 In addition, they require diagnosis of VAP. This is done by microbiological less expertise an...

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