Pneumonia associated with invasive and noninvasive ventilation: an analysis of the German nosocomial infection surveillance system database

Abstract

Purpose: Pneumonia associated with invasive mechanical ventilation (IMV) is one of the indicator infections of the German Nosocomial Infection Surveillance System. In 2005 surveillance was extended to include pneumonia associated with noninvasive ventilation (NIV). The aim of this study was to determine the utilization of IMV and NIV and the associated incidence densities (IDs) of pneumonia and to compare the characteristics of pneumonia cases and the spectrum of associated pathogens.

Methods: We analyzed the pooled data of 400 intensive care units (ICUs) with respect to three categories of pneumonia: pneumonia associated with IMV and NIV and pneumonia not associated with ventilation. Pooled ventilation utilization rates and pneumonia IDs were calculated in total and stratified by hospital size, hospital type and ICU type.

Results: Four hundred ICUs with 779,500 admitted patients, 1,068,472 IMV days and 101,569 NIV days reported 6,869 cases of pneumonia between 2005 and 2007. Of these, 5,811 cases were associated with IMV, 160 with NIV and 898 were not associated with ventilation. The mean pneumonia IDs were 1.58 and 5.44 cases per 1,000 ventilator days for NIV and IMV, respectively. Pneumonia cases associated with IMV were younger, had a longer ICU stay before onset of pneumonia and were more often associated with gram-negative bacteria than cases associated with NIV; however, there were no differences in the proportion of secondary sepsis and death.

Conclusions: This surveillance study including pneumonia associated with IMV and NIV and pneumonia not associated with ventilation shows significant differences of pneumonia IDs, patient characteristics and the spectrum of associated pathogens.