Using Ventilator-Associated Pneumonia Rates as a Health Care Quality Indicator

A Contentious Concept

Girish B. Nair, MD FACP, FCCP; Michael S. Niederman, MD, MACP, FCCP, FCCM, FERS


Semin Respir Crit Care Med. 2017;38(3):237-244. 

In This Article

Abstract and Introduction


Pneumonia is a leading cause of hospital-acquired infections, although reported rates of ventilator-associated pneumonia (VAP) have been declining in recent years. A multifaceted infection prevention approach, using a "ventilator bundle," has been shown to reduce the frequency of VAP, while improving other patient outcomes. Because of difficulties in defining VAP, the Center for Medicare and Medicaid Service introduced a new streamlined ventilator-associated event (VAE) definition in 2013 for the surveillance of complications in mechanically ventilated patients. VAE measures are increasingly being measured by institutions in the United States in place of VAP rates and as a potential measure of the quality of intensive care unit (ICU) care. However, there is increased recognition that the streamlined definitions identify a different subset of patients than those identified by traditional VAP surveillance and that VAP prevention strategies may not impact all the causes of VAE. Also, VAP and VAE rates may not always reflect the quality of care in a given ICU, especially since patient factors, beyond the control of the hospital, may impact the rates of VAP and VAE. In this review, we discuss the issues related to VAP as a quality measure and the areas of uncertainty related to the new VAE definitions.


Ventilator-associated pneumonia (VAP) is a serious nosocomial infection with substantial clinical and financial implications, incurring an additional hospital cost of ≥ 10,019 to 40,000 USD per admission.[1,2] The Center for Medicare and Medicaid Service's initiative for public reporting and performance evaluation, based on the frequency of hospital-acquired infections (HAIs), was originally conceived for reducing preventable complications in hospitalized patients and promoting a culture of safety. The Agency for Healthcare Research and Quality (AHRQ) has announced a 21% reduction in HAIs since 2010, including hospital-acquired pneumonia.[3] Similarly, the National Healthcare Safety Network (NHSN) estimates the incidence of VAP to range from 0.0 to 5.8/1,000 ventilator days.[2] These reported VAP incidence rates are considerably lower in recent years and are attributed to a multifaceted infection prevention program in the form of a "Bundle care approach" and its effective implementation.

Recently, the low incidence of VAP has been questioned. Metersky et al compared the rates of VAP reported by the Centers for Disease Control and Prevention (CDC) from 2006 to 2012, and the rates of VAP reported during the same time period by the Medicare Patient Safety Monitoring (MPSM) system.[4] They found that while the CDC surveillance system reported a decline in VAP rates from 3.2 to 0.9/1,000 ventilator days, the MPSM data found a steady rate of 10 to 11% in patients 65 and older. These findings show a true discrepancy between rates reported in a quality monitoring program, compared with rates observed in a patient care program.

According to a recent study based on cost-effectiveness modeling in Medicare patients, the introduction of various prevention programs has led to an improvement in HAI rates with a gain of 6.55 quality adjusted life year for VAP patients, and reduction in intensive care unit (ICU) costs of 163,000 USD per index admission.[5] However, an accurate diagnosis of VAP is challenging, and both surveillance and clinical definitions lack specificity or reproducibility. Using VAP as a quality benchmark and considering VAP to be a medical error may result in disingenuous reporting by health care institutions. Throughout the United States, there is an increased reporting of hospitals with a "zero incidence" of VAP, even though the antibiotic prescription and clinical diagnosis remain prevalent.[6] This prompted the CDC to introduce a new "objective" surveillance paradigm in 2013 based on complications while on the ventilator.[7] However, ventilator-associated events (VAE) identifies patients at high risk of death but has a low sensitivity and specificity in diagnosing VAP.[8] In this review, we discuss the issues related with VAP as a quality measure and areas of uncertainty related to the new VAE definitions.