Risk factors for ventilator-associated pneumonia by Pseudomonas aeruginosa in presence of recent antibiotic exposure.
BACKGROUND
To facilitate the decision-making process for therapy and prevention of ventilator-associated pneumonia (VAP) in patients undergoing recent antibiotic exposure, this study investigated whether the development of VAP episodes caused by Pseudomonas aeruginosa or other pathogens are related to different risk factors, thereby distinguishing two risk population for this serious complication.


METHODS
A 5-year retrospective case-control observational study was conducted. Cases of VAP caused by P. aeruginosa were compared with those caused by other pathogens. Univariate and multivariate analysis was performed using SPSS 11.0 software (SPSS Inc., Chicago, IL).


RESULTS
Two groups were identified: P. aeruginosa (group P) was isolated in 58 (63.7%) episodes, and 33 episodes served as controls (group C), after a median of 12 days (interquartile range, 4-28 days) and 9 days (interquartile range, 3-12.5 days) of mechanical ventilation, respectively. P. aeruginosa was identified in 34.7% of episodes with early-onset pneumonia and in 73.5% with late-onset pneumonia. In a logistic regression analysis, P. aeruginosa was independently associated with duration of stay of 5 days or longer (relative risk = 3.59; 95% confidence interval, 1.04-12.35) and absence of coma (relative risk = 8.36; 95% confidence interval, 2.68-26.09). Risk for pathogens different from P. aeruginosa (group C) in early-onset pneumonia associated with coma was estimated to be 87.5%.


CONCLUSIONS
Risk factors in episodes under recent antibiotic treatment caused by P. aeruginosa or other microorganism are not the same, a fact that could have implications for preventive and therapeutic approaches for this infection.
Rello
Jordi
J
Critical Care Department, Joan XXIII University Hospital, University Rovira & Virgili, Institut Pere Virgili, Carrer Dr. Mallafre Guasch 4, 43007 Tarragona, Spain. jordi.rello@urv.cat
Allegri
Camilla
C
Rodriguez
Alejandro
A
Vidaur
Loreto
L
Sirgo
Gonzalo
G
Gomez
Frederic
F
Agbaht
Kemal
K
Pobo
Angel
A
Diaz
Emili
E
D018806:APACHE; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016022:Case-Control Studies; D003128:Coma / Q000150:complications; D016208:Databases, Factual; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D018410:Pneumonia, Bacterial / Q000453:epidemiology* / Q000382:microbiology*; D011552:Pseudomonas Infections / Q000453:epidemiology* / Q000382:microbiology*; D012121:Respiration, Artificial / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors; D009626:Terminology as Topic; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents