Impact of air pollution on exacerbations of respiratory and cardiovascular diseases for the intensivist: a narrative review.

Air pollution is a major global health threat, yet its specific impact on critically ill patients remains underexplored. While the link between air pollution and respiratory and cardiovascular events is well-documented, its contribution to organ dysfunction in the ICU setting requires a comprehensive synthesis for the intensivist. This narrative review aims to summarize the pathophysiological mechanisms and epidemiological evidence linking short-term and long-term air pollution exposure to exacerbations of respiratory and cardiovascular diseases, with a focus on critical illness. We therefore conducted a comprehensive review of the literature, focusing on clinical studies and mechanistic models. We specifically examined the impact of particulate matter and gaseous pollutants on ICU-specific outcomes. Evidence indicates that air pollution notably acts as a potent trigger for acute respiratory distress syndrome, acute lower respiratory infections, and exacerbations of chronic obstructive pulmonary disease and asthma. Higher levels of air pollution are associated with acute cardiovascular events leading to hospital admission, especially myocardial infarction, stroke, acute heart failure, and arrhythmia. Recent data suggest that long-term exposure significantly increases the susceptibility to critical illness, while short-term peaks are associated with immediate spikes in ICU mortality and morbidity. In conclusion, air pollution is a silent but significant contributor to the burden of critical illness. For the intensivist, understanding these environmental determinants is crucial for both clinical risk assessment and public health advocacy. Future research must bridge the gap between general population observations and direct clinical evidence in the ICU to refine protective strategies in the context of a changing climate.