Ventilator-associated pneumonia incidence

Kollef, M.H. Vlasnik, J. Sharpless, L. Pasque, C. Murphy, D. Fraser, V. Schedule changes of antibiotic classes A strategy to decrease the incidence of ventilator associated pneumonia. Am. J. Respir. Crit. Care Med. 1997, i56(4 Pt. 1), 1040 1048. 

There were, however, some convincing examples of major improvements within the run chart data collected locally some of the data capture was clearly both sustained and controlled (Box 19.4). For instance, patients received correctly timed antibiotics before surgery and the introduction of a care bundle in one site significantly reduced the incidence of ventilator associated pneumonia. In patients on mechanical ventilation, the cumulative risk of pneumonia increases with the duration of ventilation. This infection has serious potential complications and a high mortality rate, so improvement in the reliability of the care delivered has important implications. 

Marelich GP, Murin S, Battistella F, et al. Protocol weaning of mechanical ventilation in medical and surgical patients by respiratory care practitioners and nurses. Effect on weaning time and incidence of ventilator-associated pneumonia. Chest 2000 118 459-467. 

Most of the published studies report the incidence rate of nosocomial pneumonia, that is, the number of cases of nosocomial pneumonia per 100 hospitalized patients. In six studies summarized in Table 3, the incidence of ventilator-associated pneumonia ranged from 9% to 24% (20). These rates fail to adjust for the duration of ventilation and are therefore difficult to interpret. Device-associated incidence density rates of nosocomial pneumonia, that is, the number of cases of ventilator-associated pneumonia per 1000 ventilator-days, are reported only for three studies and range from 10 to 30 per 1000 ventilator-days (14,21). In the NNIS, rates of ventilator-associated pneumonia per 1000 ventilator-days range from 9.4 in medical ICUs to 14.9 in surgical ICUs, 16.9 in trauma ICUs and 20.9 in burn ICUs. 

Incidence density rates of ventilator-associated pneumonia and nonventilator-associated pneumonia (reported by the NNIS system) from 1990 to 1996 are shown in Figure 2. On average, ventilator-associated pneumonia rates are 9.3 times higher than nonventilator-associated pneumonia rates, ranging from 2.6 times higher in respiratory ICUs to 19 times higher in burn ICUs. 

Table 3 Incidence and Mortality Rate of Ventilator-Associated Pneumonia...

In intensive care units (ICUs), pneumonia is the most frequent nosocomial infection (1-3) and occurs most often as ventilator-associated pneumonia (VAP) in patients on mechanical ventilation. The overall incidence of VAP in different studies varies between 10% and 85%, depending on the patient population and the criteria used to establish the diagnosis. Ventilator-associated pneumonia has been associated with an attributable mortality rate ranging from 13% to 47% (4-7), although this is not a consistent finding (8-10). 

Pugin J, Auckenthaler R, Lew DP, Suter PM. Oropharyngeal decontamination decreases incidence of ventilator-associated pneumonia a randomized, placebo-controlled, double-blind clinical trial. J Am Med Assoc 1991 265 2704-2710. 

In a prospective study of enteral-based nutritional support regimen in bums and tramna patients, those receiving the highest amoxmts of enteral calories within the first week had the highest incidence of ventilator-assisted pneumonia and the lowest incidence of bacteraemia. PN was associated with a significantly increased risk of bacteraemia (OR=2.5 95% Cl 1.8-3.5), ventilator-assisted pneumonia (OR=2.5 95% Cl 1.7-3.3), and death (OR=1.9 95% Cl 1.1-3.1) [104 ]. A retrospective review of 12 cases of multiple sclerosis patients on home PN showed that there was no improvement in their fxmctional status there were also no significant changes in liver enzymes and bilirubin [105 ]. Five of the patients died within two years form causes unrelated to parenteral nutrition. 

Kirton OC, DeHaven B, Morgan J, Morejon O, Civetta J. A prospective, randomized comparison of an in-line heat moisture exchange filter and heated wire humidifiers Rates of ventilator associated early-onset (community-acquired) or late-onset (hospital-acquired) pneumonia and incidence of endotracheal tube occlusion. Chest. In Press. 

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