Incidence and Risk Factors for Ventilator-associated Pneumonia in an Intensive Care Unit of a Tertiary Hospital / 병원감염관리

ABSTRACT

BACKGROUND: Ventilator-associated pneumonia (VAP) is the most severe form of nosocomial infection. However the actual incidence of pneumonia associated with ventilator is not known. The purpose of this study is to examine the incidence of VAP, find out related risk factors, and establish effective preventive measures. METHODS: The medical records of 172 consecutive patients, who have been admitted to the intensive care unit (ICU) from January 2005 to October 2005 and were subjected to mechanical ventilation for more than 48 hours, have been reviewed retrospectively. VAP was defined according to the definition of CDC (1992). The statistical software SPSS (version 12.0) was used to conduct descriptive and comparative analysis including Chi-square, student's t-test, and logistic regression. RESULTS: The incidence was 163 per 1,000 persons and 19.0 per 1,000 ventilator use patient-days. The significant risk factors for VAP were type of ICU (surgical ICU, OR=5.942, 95% CI=1.894-8.644) and duration of ventilator use (OR=3.603, 95% CI=1.810-7.173). VAP developed 3.04 (+/-0.88) days after initiating mechanical ventilation. Causative agents of VAP were Acinetobacter baumanii (35.2%), MRSA (18.8%), Enterobacter aerogenes (12.4%), Klebsiella pneumonia (9.4%), Staphylococcus aureus (6.3%), Burkholderia (6.3%), Serratia marcesceus (6.3%), Stenotrophomonas (3.1%), and Pseudomonas (3.1%) spp. CONCLUSION: Type of ICU (surgical ICU, OR=5.942, 95% CI=1.894-18.644) and duration of ventilator use (OR=3.603, 95% CI=1.810-7.173) were considered to increase the incidence of VAP. Further study with larger number of cases and preventive measures would be necessary to identify risk factors related to the ventilator-associated pneumonia.