Relationship between inhaled β₂-agonists and ventilator-associated pneumonia: a cohort study.
OBJECTIVE
To determine the impact of aerosolized bronchodilators on ventilator-associated pneumonia.


METHODS
Prospective cohort study.


METHODS
A 30-bed medical and surgical intensive care unit.


METHODS
All intubated patients requiring mechanical ventilation for >48 hrs were eligible during a 13-month period. Nebulized β2-agonists were administered at the intensive care unit physician's discretion. Ventilator-associated pneumonia definition included clinical and quantitative microbiological criteria. Only first ventilator-associated pneumonia episodes were analyzed. Risk factors for ventilator-associated pneumonia were determined using univariate and multivariate analyses. The influence of inhaled β2-agonists on ventilator-associated pneumonia occurrence was also adjusted for confounding factors using Cox's proportional-hazards model.


RESULTS
Ventilator-associated pneumonia was diagnosed in 137 (31%) of the 439 enrolled patients. Ventilator-associated pneumonia was early-onset in 14 (10%) patients. The incidence rate of ventilator-associated pneumonia was 20 per 1,000 ventilator days. Ventilator-associated pneumonia was polymicrobial in 16 (11%) patients, and related to multidrug-resistant bacteria in 42 (28%) patients. Most cases of ventilator-associated pneumonia were caused by Gram-negative bacteria. Inhaled β2-agonists were significantly more frequently used in patients with ventilator-associated pneumonia compared with those without ventilator-associated pneumonia (49% vs. 34%, odds ratio [95% confidence interval] = 1.9 [1.2-2.8], p = .003). Multivariate analysis identified aerosolized β2-agonists (odds ratio [95% confidence interval] = 1.7 [1.1-2.6], p = .012), Simplified Acute Physiology Score II at intensive care unit admission (odds ratio [95% confidence interval] = 1.01 [1.001-1.02] per point, p = .031), and red blood cell transfusion (odds ratio [95% confidence interval] = 2 [1.3-3.1], p = .001) as independent risk factors for ventilator-associated pneumonia. Cox's proportional-hazards model also identified inhaled β2-agonists as a risk factor for ventilator-associated pneumonia (odds ratio [95% confidence interval] = 1.52 [1.06-2.19], p = .021).


CONCLUSIONS
Use of aerosolized bronchodilators in intensive care unit mechanically ventilated patients is an independent risk factor for ventilator-associated pneumonia.
Intensive Care Unit, CHU de Lille, Lille, France.
Emmanuelle
E
Jaillette
Saad
S
Nseir
D058666:Adrenergic beta-2 Receptor Agonists / Q000009:adverse effects*; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D053717:Pneumonia, Ventilator-Associated / Q000139:chemically induced* / Q000209:etiology / Q000382:microbiology; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors
D058666:Adrenergic beta-2 Receptor Agonists