Where it is
From the carina, the right and left main bronchi enter the lungs at the hilum and divide into lobar, segmental and smaller bronchi, then bronchioles.
What it does
Conduct and distribute air. Smooth muscle in the bronchiole walls can constrict (bronchospasm) or relax.
Clinical relevance
- Asthma narrows the bronchioles through inflammation, mucus and smooth muscle spasm.
- Beta-2 agonists such as albuterol relax bronchial smooth muscle.
- Aspiration pneumonia most often affects the right lower lobe.
Nursing focus
- Teach inhaler use: shake, exhale, seal lips, press and inhale slowly, hold the breath 10 seconds; use a spacer when possible.
- Rinse the mouth after inhaled corticosteroids to prevent thrush.