Ventilator-associated pneumonia: the clinical pulmonary infection score as a surrogate for diagnostics and outcome

The Clinical Pulmonary Infection Score (CPIS) was developed to serve as a surrogate tool to facilitate the diagnosis of ventilator-associated pneumonia (VAP). The CPIS is calculated on the basis of points assigned for various signs and symptoms of pneumonia (eg, fever and extent of oxygenation impairment). Although some studies suggest that a CPIS >6 may correlate with VAP, most studies indicate that the CPIS has limited sensitivity and specificity. In addition, no well-done studies validate the CPIS in either acute lung injury or trauma. The interobserver variability in CPIS calculation remains substantial, suggesting that this cannot be routinely used across multiple centers to support the conduct of randomized clinical trials. Changes in the CPIS may correlate with outcomes in VAP, but it appears that the ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen is a more important marker for outcomes than the CPIS. At present, the CPIS has a limited role both clinically and as a research tool.