Bronchial Hygiene: Secretion Clearance Versus Lung Expansion
Two distinct goals
Bronchial hygiene has two separate aims: moving secretions out and keeping alveoli open. Secretion clearance uses postural drainage with percussion and vibration, high-frequency chest wall oscillation, PEP and oscillating-PEP devices (Flutter, Acapella), autogenic drainage, huff coughing, and suctioning. Lung expansion uses incentive spirometry, IPPB, and early mobilization. Aerosolized agents - bronchodilators, hypertonic saline, dornase alfa for cystic fibrosis - support these techniques rather than replace them.
Sequencing
A useful rule is "medicate, drain, expand": bronchodilator first to open airways, then airway clearance, then incentive spirometry. Suction only when the patient cannot clear secretions; preoxygenate, limit each pass to 10–15 seconds, and use sterile technique.
Traps
Incentive spirometry prevents and treats atelectasis - it does not clear secretions. Postural drainage has real contraindications: increased intracranial pressure, unstable spine or fractures, recent hemoptysis, untreated pneumothorax, and recent chest or abdominal surgery. Avoid percussion over the spine, sternum, kidneys, and breast tissue, and stop if the patient becomes dyspneic or desaturates. PEP therapy is a poor choice for a patient who cannot tolerate increased work of breathing.
Worked example
A postoperative patient with atelectasis and scant secretions: order incentive spirometry every hour while awake with a goal of sustained maximal inspiration - not a PEP valve. A patient with copious secretions and a weak cough instead gets a bronchodilator, then assisted cough or suction, then positioning, with IS only after the airway is clear.