369. The Use of Serial Surveillance Endotracheal Aspirates (EA) Cultures for Microbiologic Diagnosis of Ventilator-Associated Respiratory Infections (VARI)
Session: Poster Abstract Session: Community and Healthcare Acquired Pneumonia - Epidemiology
Friday, October 21, 2011
Room: Poster Hall B1
Background:

VARI, which includes ventilator-associated tracheobronchitis (VAT) and pneumonia (VAP), is associated with increased patient morbidity and mortality.  We hypothesized that daily EA surveillance cultures would facilitate earlier identification of multidrug-resistant (MDR) pathogens, diagnosis and treatment, prevent VAP and improve patient outcomes. 

Methods:

We performed a prospective, observational study of 98 mixed intensive care unit patients intubated for ≥ 48h. Semi-quantitative endotracheal aspirates (SQ-EA) cultures were examined daily (STUDY group); results were not reported back to clinicians (MD). Microbiologic VARI was defined as EA cultures with moderate (+++) or heavy (++++) growth. The STUDY and MD groups were compared in terms of time to first positive culture (median days) and for specific pathogens. Kaplan-Meier curves and test of correlated proportions were used for analysis, a p- <0.05 is significant.

 

Results:

STUDY samples had a significantly higher positive yield vs MD samples: 40% vs 19% by ++++ criteria (p<.0001) and 57% vs 44% by +++ criteria (p<.01). Pathogens were identified sooner in the STUDY vs the MD group for +++ growth: (7 vs. 11 days in 11 days, p=0.0012). The estimated % of patients that would test positive by day 7 was also significantly higher in the STUDY group: 52% vs 47% by +++ criteria and 39% vs 20% by ++++ criteria. Distribution of multidrug-resistant (MDR) pathogens, such as Pseudomonas aeruginosa, Acinetobacter species, and methicillin resistant Staphylococcus aureus (MRSA) was similar in both groups; Enterobactericeae were more commonly identified in the STUDY group (p< .05).

 

Conclusion:

Surveillance samples with microbiologic criteria for VARI were positive in significantly more subjects and sooner than MD samples. The VARI model allows earlier identification of MDR pathogens that would facilitate earlier institution of infection control measures, such as proper patient isolation. In addition information on MDR pathogens and antibiotic sensitivity data would be available to clinicians for earlier, targeted antibiotic therapy of VARI.  Focusing on and treating VARI when clinical signs develop, may prevent VAP and improve patient outcomes. Farther studies to assess the VARI model are needed.


Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

Jana Hudcova, MD1,2, Yuxiu Lei, Ph.D3, Robin Ruthazer, MPH4, Akmal Sarwar, MD5 and Donald Craven, MD, FIDSA3,6, (1)Anaesthesia, Tufts Medical Center, Boston, MA, (2)Surgical Critical Care, Lahey Clinic, Burlington, MA, (3)Center for Infectious Disease & Prevention, Lahey Clinic, Burlington, MA, (4)Tufts Medical Center, Boston, MA, (5)Pulmonary & Critical Care Medicine, Lahey Clinic, Burlington, MA, (6)Tufts University School of Medicine, Burlington, MA

Disclosures:

J. Hudcova, None

Y. Lei, None

R. Ruthazer, None

A. Sarwar, None

D. Craven, pfizer: Consultant, Investigator, Scientific Advisor and Speaker's Bureau, Consulting fee, Grant recipient and Speaker honorarium

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