Critical Care Plus: VAP: High Costs in More Ways than One, says CDC Guideline
The fatality rates for hospital-associated pneumonia in general, and of ventilator-associated pneumonia (VAP) in particular, are high. For hospital-associated pneumonia, attributable mortality rates of 20% to 33% have been reported, according to the draft pneumonia prevention guideline by the Centers for Disease Control and Prevention (CDC).1 Here are some other findings gleaned from the draft document:
In one study, VAP accounted for 60% of all deaths due to hospital-associated infections. In studies in which invasive techniques were used to diagnose VAP, the crude mortality rates ranged from 4% in patients with VAP—but without antecedent antimicrobial therapy—to 73% in patients with VAP caused by Pseudomonas or Acinetobacter species. Attributable mortality rates ranged from 5.8% to 13.5%.
The wide ranges in crude and attributable mortality rates strongly suggest that a patient’s risk of dying from VAP is affected by multiple other factors, such as underlying disease, organ failure, receipt of antimicrobial agent, and the type of infecting organism.
Analyses of pneumonia-associated morbidity have shown that hospital-associated pneumonia can prolong ICU stay by an average of 4.3 days and hospitalization by four to nine days. A conservative estimate of the direct cost of excess hospital stay due to pneumonia in 1993 was $1.2 billion a year for the nation.
Pneumonia accounts for approximately 15% of all hospital-associated infections and 27% and 24% of all infections acquired in the medical ICU and coronary care unit, respectively. It is the second most common hospital-associated infection after that of urinary tract.
The primary risk factor for the development of hospital-associated bacterial pneumonia is mechanical ventilation (with its requisite endotracheal intubation). The CDC’s National Nosocomial Infection Surveillance System (NNIS) reported that in 1986-1990, the median rate of VAP per thousand ventilator-days in NNIS hospitals ranged from 4.7 in pediatric ICUs to 34.4 in burn ICUs. The median rate of nonventilator-associated pneumonia per 1,000 ICU days ranged from zero in pediatric and respiratory ICUs to 3.2 in trauma ICUs.
Studies indicate that patients receiving continuous mechanical ventilation have six to 21 times the risk of developing hospital-associated pneumonia compared with patients who are not vented. Because of this tremendous risk, in the last two decades, most of the research on hospital-associated pneumonia has been focused on VAP.
1. Centers for Disease Control and Prevention. Healthcare Infection Control Practices Advisory Committee. Draft Guideline For Prevention Of Healthcare-Associated Pneumonia. Atlanta; 2002.