Chest
Volume 146, Issue 6, December 2014, Pages 1612-1618
Journal home page for Chest

Original Research: Chest Infections
Automated Surveillance for Ventilator-Associated Events

https://doi.org/10.1378/chest.13-2255Get rights and content

Abstract

BACKGROUND:The US Centers for Disease Control and Prevention has implemented a new, multitiered definition for ventilator-associated events (VAEs) to replace their former definition of ventilator-associated pneumonia (VAP). We hypothesized that the new definition could be implemented in an automated, efficient, and reliable manner using the electronic health record and that the new definition would identify different patients than those identified under the previous definition.

METHODS:We conducted a retrospective cohort analysis using an automated algorithm to analyze all patients admitted to the ICU at a single urban, tertiary-care hospital from 2008 to 2013.

RESULTS:We identified 26,466 consecutive admissions to the ICU, 10,998 (42%) of whom were mechanically ventilated and 675 (3%) of whom were identified as having any VAE. Any VAE was associated with an adjusted increased risk of death (OR, 1.91; 95% CI, 1.53-2.37;P< .0001). The automated algorithm was reliable (sensitivity of 93.5%, 95% CI, 77.2%-98.8%; specificity of 100%, 95% CI, 98.8%-100% vs a human abstractor). Comparison of patients with a VAE and with the former VAP definition yielded little agreement (κ = 0.06).

CONCLUSIONS:A fully automated method of identifying VAEs is efficient and reliable within a single institution. Although VAEs are strongly associated with worse patient outcomes, additional research is required to evaluate whether and which interventions can successfully prevent VAEs.

Section snippets

Setting

The study was performed at the Beth Israel Deaconess Medical Center, a tertiary care, urban hospital in Boston, Massachusetts, with > 70 intensive care beds in nine ICUs. The study was reviewed by the hospital's institutional review board and was granted a waiver of informed consent (protocol number 2013-P000062).

Study Design and Data Sources

All patients aged ≥ 18 years admitted to any of the hospital's nine ICUs from July 1, 2008, to March 31, 2013, were included in the study. We extracted prospectively collected

Results

A total of 26,466 consecutive hospital admissions were included for analysis. Of these, 10,998 (42%) required mechanical ventilation, with an average duration of mechanical ventilation of 4 days (median, 2 days; interquartile range, 1-5 days) and a total number of 46,850 ventilated days. There were 3,302 patients ventilated for ≥ 4 days continuously.

Discussion

Our results show that, in a large cohort of consecutive ICU admissions, the CDC's new definition for VAEs identifies patients with increased risk of death, longer lengths of stay, and decreased likelihood of returning home following hospitalization. Our study also demonstrates the feasibility of complete automation of screening for VAE, potentially saving thousands of hours of staff time spent in chart review. Finally, although patients were at increased risk of death when identified under

Conclusions

In a large cohort of consecutive ICU admissions, the CDC's new definition for VAEs effectively identifies patients at greater risk of poor outcomes. The new surveillance definition for VAEs put forth by the CDC represents a substantial step forward toward generating a reliable method of identifying iatrogenic complications from mechanical ventilation. However, it is not yet clear whether the new definition identifies an iatrogenic cause of patient illness that can be intervened upon or,

Acknowledgments

Author contributions:J. P. S. had full access to all of the data, conducted all analyses, and takes responsibility for the integrity of the data and the accuracy of the data analysis. J. P. S. contributed to and revised the manuscript; M. D. H. served as senior author, participating in all phases of the study, and contributed to and critically revised the manuscript; G. S., J. G., D. T., and M. K. contributed to study design and analyses and critically revised the manuscript; V. N. contributed

References (21)

There are more references available in the full text version of this article.

Cited by (0)

Dr Klompas is currently at Harvard Pilgrim Health Care Institute (Boston, MA).

FUNDING/SUPPORT:This work was supported by the Centers for Disease Control [Grant U54 CK000172-01S1], the Public Health Prevention Fund Ventilator-associated pneumonia ACA, with Dr Klompas as overall PI and Dr Howell as site PI at Beth Israel Deaconess Medical Center.

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.

View full text