Accuracy of clinical definitions of ventilator-associated pneumonia: comparison with autopsy findings.
METHODS
We studied patients requiring mechanical ventilation for more than 48 hours who died in the intensive care unit and whose bodies were autopsied. We evaluated 3 clinical definitions of ventilator-associated pneumonia: loose definition, defined as chest radiograph infiltrates and 2 of 3 clinical criteria (leukocytosis, fever, purulent respiratory secretions); rigorous definition, defined as chest radiograph infiltrates and all of the clinical criteria; and a clinical pulmonary infection score higher than 6 points. Sensitivity, specificity, and likelihood ratios were calculated by using pathology pattern as criterion standard.


RESULTS
One hundred forty-two (56%) of the 253 patients included had histological criteria of pneumonia. Patients who met the clinical criteria of ventilator-associated pneumonia were 163 (64%) for the loose definition, 32 (13%) for the rigorous definition, and 109 (43%) for the clinical pulmonary infection score. The operative indexes (sensitivity and specificity) of each definition were as follows: loose definition, 64.8% and 36%; rigorous definition, 91% and 15.5%; and clinical pulmonary infection score higher than 6, 45.8% and 60.4%. The addition of microbiological data to the clinical definitions increased the specificity and decreased the sensitivity but not significantly.


CONCLUSIONS
Accuracy of 3 commonly used clinical definitions of ventilator-associated pneumonia was poor taking the autopsy findings as reference standard.
Tejerina
Eva
E
Intensive Care Unit, Hospital Universitario de Getafe, Carretera de Toledo, kilómetro 12.5, 28905 Getafe (Madrid), Spain. evateje@gmail.com
Esteban
Andrés
A
Fernández-Segoviano
Pilar
P
Frutos-Vivar
Fernando
F
Aramburu
José
J
Ballesteros
Daniel
D
Rodríguez-Barbero
José María
JM
D000368:Aged; D001344:Autopsy; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D053717:Pneumonia, Ventilator-Associated / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity