What is the purpose and procedure of postural drainage in patients with excessive mucus production?

Postural Drainage: Purpose and Procedure

Postural drainage is a gravity-assisted positioning technique used to facilitate mucus clearance from specific bronchopulmonary segments in patients with excessive sputum production, particularly those with cystic fibrosis and bronchiectasis, though its benefits are modest and require proper technique with adequate drainage time (3-15 minutes per position). 1, 2

Purpose and Mechanism

Postural drainage uses gravity to mobilize secretions from peripheral airways toward central airways where they can be expectorated. 1 While gravity is not the primary mechanism for normal secretion clearance, it plays a major role in ventilation patterns and secretion mobilization in patients who produce large quantities of sputum and have difficulty clearing it. 2

The technique is most beneficial for:

• Cystic fibrosis patients - where it has demonstrated efficacy in increasing mucus clearance 1
• Bronchiectasis patients - particularly those with hypersecretion and inability to expectorate effectively 1
• Patients with excessive sputum production who cannot clear secretions independently 2

Procedure and Technique

Patient Positioning

Review CT imaging to identify affected bronchopulmonary segments and teach appropriate postural drainage positions targeting those specific areas. 1 Each position should be maintained for 3-15 minutes to allow adequate drainage time, as benefits are technique-dependent. 2

Consider gravity-assisted positioning (where not contraindicated) to enhance airway clearance technique effectiveness. 1

Modified Approach When Standard Positioning Contraindicated

Use modified postural drainage without head-down tilt in patients for whom traditional postural drainage is contraindicated or not tolerated. 1 If gastroesophageal reflux symptoms increase with modified positioning, teach airway clearance techniques in the sitting position instead. 1

Integration with Other Techniques

Combine postural drainage with forced expiration technique (huffing) rather than relying on percussion and vibration alone. 1 The forced expiration technique consists of one or two forced expirations without glottic closure, starting from mid-lung to low lung volume, followed by relaxed breathing. 1

Evidence shows that:

• Active cycle of breathing techniques plus postural drainage enhances sputum expectoration compared to techniques performed in sitting position alone 1
• Huffing with postural drainage improves sputum clearance compared to no treatment in CF patients 1
• Percussion and vibration add questionable additional value beyond postural drainage with forced expiration 1

Treatment Duration and Frequency

Advise patients to perform airway clearance for a minimum of 10 minutes up to a maximum of 30 minutes, continuing until two clear huffs or coughs are completed or until fatigue begins. 1 The frequency should be tailored to individual needs and increased during infectious exacerbations. 1

Important Caveats and Contraindications

When to Avoid

Do not use postural drainage in patients with COPD if combined with manually assisted cough, as this may be detrimental and decrease peak expiratory flow rate. 1 Standard postural drainage alone remains acceptable in COPD when combined with huffing. 1

Monitoring Requirements

Monitor patients for symptom improvement and oxygen saturation during treatment. 1 Studies show postural drainage with percussion can cause oxygen desaturation (from 93.3% to 91.2%), requiring 15 minutes post-treatment to return to baseline, whereas alternative techniques like autogenic drainage may avoid this complication. 3

Alternative Techniques

Teach autogenic drainage as an adjunct to postural drainage in CF patients, as it can be performed without assistance and in one position while achieving comparable or faster mucus clearance. 1 Autogenic drainage cleared mucus faster than postural drainage in CF patients without significant differences in spirometry. 1

Offer active cycle of breathing techniques or oscillating positive expiratory pressure as primary options for bronchiectasis patients. 1

Clinical Reality

While postural drainage is considered a mainstay treatment for bronchiectasis and CF, the long-term effectiveness remains unknown and effects on quality of life, exacerbation rates, hospitalizations, and mortality have not been established. 1 The technique requires considerable time investment and proper application to achieve benefits. 2 Patient preference and adherence should guide selection among equivalent airway clearance techniques. 1