Pre-admission air pollution exposure prolongs the duration of ventilation in intensive care patients.

ABSTRACT

PURPOSE: Air pollutant exposure constitutes a serious risk factor for the emergence or aggravation of (existing) pulmonary disease. The impact of pre-intensive care ambient air pollutant exposure on the duration of artificial ventilation was, however, not yet established. METHODS: The medical records of 2003 patients, admitted to the intensive care unit (ICU) of the Antwerp University Hospital (Flanders, Belgium), who were artificially ventilated on ICU admission or within 48 h after admission, for the duration of at least 48 h, were analyzed. For each patient's home address, daily air pollutant exposure [particulate matter with an aerodynamic diameter ≤ 2.5 µm (PM2.5) and ≤ 10 µm (PM10), nitrogen dioxide (NO2) and black carbon (BC)] up to 10 days prior to hospital admission was modeled using a high-resolution spatial-temporal model. The association between duration of artificial ventilation and air pollution exposure during the last 10 days before ICU admission was assessed using distributed lag models with a negative binomial regression fit. RESULTS: Controlling for pre-specified confounders, an IQR increment in BC (1.2 µg/m3) up to 10 days before admission was associated with an estimated cumulative increase of 12.4% in ventilation duration (95% CI 4.7-20.7). Significant associations were also observed for PM2.5, PM10 and NO2, with cumulative estimates ranging from 7.8 to 8.0%. CONCLUSION: Short-term ambient air pollution exposure prior to ICU admission represents an unrecognized environmental risk factor for the duration of artificial ventilation in the ICU.