RELATIONSHIP OF MICROBIOLOGIC DIAGNOSTIC-CRITERIA TO MORBIDITY AND MORTALITY IN PATIENTS WITH VENTILATOR-ASSOCIATED PNEUMONIA

Objective.-To evaluate whether the mortality and the morbidity of vent ilator-associated pneumonia, defined by positive result of protected s pecimen brush culture, was different from that defined by other method s, Design.-Matched-cohort study. All patients with clinical suspicion of pneumonia were investigated with protected specimen brush, bronchoa lveolar lavage, and blind bronchial samplings. Two groups were defined : brush-positive patients (positive culture of the protected specimen brush) and brush-negative patients (negative culture of the protected specimen brush, but positive culture with another method). Setting.-A 14-bed medicosurgical intensive care unit (ICU) in an 850-bed teaching hospital, Patients.-All patients with documented ventilator-associate d pneumonia over 4 years 9 months, A total of 102 cases documented by protected specimen brush culture and 223 documented by another samplin g procedure, Patients were matched according to diagnosis on admission , age, sex, date of admission, Acute Physiology and Chronic Health Eva luation II (APACHE II) score, and date of onset of pneumonia, Main Out come Measures.-Mortality rate, duration of mechanical ventilation, dur ation of ICU stay, duration of hospital stay, sampling methods, and mi crobiologic cultures, Results.-A total of 76 pairs were submitted for analysis, The effectiveness of matching was 81.85%, There was no diffe rence in mortality between brush-positive patients and brush-negative patients, The ICU fatality rate was 38% in the brush-positive group an d 39.4% in the brush-negative group (odds ratio [OR], 0.95; 95% confid ence interval [CI], 0.46-1.93), The hospital fatality rate was 41% (OR , 1;95% CI, 0.5-2.01), The mean (SD) duration of ventilation was 26 (2 3) days in the 2 groups (range, 3-132 days). The duration of ICU stay was 33 (27.4) days in the 2 groups (range, 3-152 days), Conclusions.-W hen confounding factors are controlled, patient outcome is the same if ventilator-associated pneumonia has been diagnosed by protected speci men brush or by another sampling method.