Ventilator-associated pneumonia. A multivariate analysis.
OBJECTIVE
To identify factors associated with the development of ventilator-associated pneumonia (VAP) and to examine the incidence of VAP in different intensive care unit (ICU) populations.


METHODS
An inception cohort study.


METHODS
Barnes Hospital, St Louis, Mo, an academic tertiary care center.


METHODS
A total of 277 consecutive patients required mechanical ventilation for longer than 24 hours from a medical ICU (75 patients), surgical ICU (100 patients), or cardiothoracic ICU (102 patients).


METHODS
Prospective patient surveillance and data collection.


METHODS
Ventilator-associated pneumonia and ICU mortality.


RESULTS
Ventilator-associated pneumonia occurred in 43 patients (15.5%). Stepwise logistic regression analysis identified four factors to be independently associated with VAP (P < .05): an organ system failure index of 3 or greater (adjusted odds ratio [AOR] = 10.2; 95% confidence interval [CI], 4.5 to 23; P < .001); patient age of 60 years or older (AOR = 5.1; 95% CI, 1.9 to 14.1; P = .002); prior administration of antibiotics (AOR = 3.1; 95% CI, 1.4 to 6.9; P = .004); and supine head positioning during the first 24 hours of mechanical ventilation (AOR = 2.9; 95% CI, 1.3 to 6.8; P = .013). Ventilator-associated pneumonia occurred more often in cardiothoracic patients (21.6%) compared with medical patients (9.3%) (P = .03). Patients with VAP also had a higher mortality (37.2%) than those without VAP (8.5%) (P < .001). An organ system failure index of 3 or greater (AOR = 16.1; 95% CI, 6.1 to 42; P < .001), a premorbid lifestyle score of 2 or greater (AOR = 3.1; 95% CI, 1.3 to 7.3; P = .012), and supine head positioning during the first 24 hours of mechanical ventilation (AOR = 3.1; 95% CI, 1.2 to 7.8; P = .016) were independently associated with mortality.


CONCLUSIONS
These data suggest potential interventions that might affect the incidence of VAP or outcome associated with VAP. Additionally, they indicate that different ICU populations may have different incidences of VAP.
Kollef
M H
MH
Department of Internal Medicine, Washington University School of Medicine, St Louis, MO 63110.
D000368:Aged; D016507:Cardiology Service, Hospital / Q000706:statistics & numerical data; D015331:Cohort Studies; D005260:Female; D006746:Hospital Bed Capacity, 500 and over; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008923:Missouri / Q000453:epidemiology; D015999:Multivariate Analysis; D011014:Pneumonia / Q000453:epidemiology* / Q000209:etiology* / Q000401:mortality; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000009:adverse effects* / Q000379:methods / Q000706:statistics & numerical data; D012307:Risk Factors; D013503:Surgery Department, Hospital / Q000706:statistics & numerical data