- 2.7 million children (<18 yr) affected annually in the U.S.
- 850,000 ED visits per year in the U.S.
- Inflammatory events, usually viral, lead to bronchoconstriction:
- Compounded by hyperreactivity of airways
- Mediators of the inflammatory cascade exacerbate symptoms
- Airway obstruction produces increased airway resistance and gas trapping:
- Mucosal edema
- Mucous plugging
- Infants more vulnerable to respiratory failure:
- Increased peripheral resistance
- Decreased elastic recoil with early airway closure
- Unstable rib cage
- Mechanically disadvantaged diaphragm
- Family history of allergy
- Medical history of early injury to airway (bronchopulmonary dysplasia, pneumonia, intubation, croup, reflux, passive exposure to smoking), reactions to foods and drugs, other allergic manifestations
- Environmental exposures such as pets, smoke, carpets, or dust may trigger or exacerbate
- Environment: Pollens, grasses, mold, house dust mites, and animal dander
- Occupational chemicals: Chlorine, ammonia – food and additives
- Irritants: Smoke, pollutants, gases, and aerosols
- Cold weather
- Emotional: Stress, phobia
- Intoxication: β-blockers, aspirin, NSAIDs
There's more to see -- the rest of this topic is available only to subscribers.