Postural Drainage of Bronchopulmonary Segments
Principle
Postural drainage uses gravity to drain secretions from specific bronchopulmonary segments toward the main bronchi, where they can be cleared by coughing. The patient is positioned so that the affected segment is uppermost and its draining bronchus points downward.
Used in: bronchiectasis, cystic fibrosis, lung abscess, chronic obstructive pulmonary disease, post-operative atelectasis.
Dependent Segments by Position
| Position | Most Dependent Segment(s) | Clinical Relevance |
|---|---|---|
| Supine | Superior (apical) of lower lobe — right > left | Aspirated material lodges here; aspiration pneumonia |
| Prone | Posterior basal of lower lobe | Secretions pool here; drainage achieved by lying prone |
| Left lateral decubitus | Right-sided segments become dependent | Secretions from right bronchial tree flow toward carina → stimulates cough reflex |
| Right lateral decubitus | Left-sided segments become dependent | — |
| Sitting/erect | Basal segments of lower lobes | Most common sites of pneumonia (gravity-dependent) |
| Trendelenburg (head-down) | Anterior segments of upper lobes | Used for draining upper lobe segments |
Postural Drainage Positions by Segment
Right Lung
| Segment | Drainage Position |
|---|---|
| Apical (S1) | Sitting upright, leaning slightly back |
| Posterior (S2) | Sitting, leaning forward over pillow |
| Anterior (S3) | Supine, flat |
| Lateral — Middle lobe (S4) | Left lateral, foot of bed elevated 15°, rotate slightly forward |
| Medial — Middle lobe (S5) | Left lateral, foot of bed elevated 15°, rotate slightly backward |
| Superior/Apical — Lower lobe (S6) | Prone, flat (or prone with pillow under abdomen) |
| Medial basal (S7) | Left lateral, foot of bed elevated 20° |
| Anterior basal (S8) | Supine, foot of bed elevated 20° |
| Lateral basal (S9) | Right lateral, foot of bed elevated 20° |
| Posterior basal (S10) | Prone, foot of bed elevated 20° |
Left Lung
| Segment | Drainage Position |
|---|---|
| Apical (S1) | Sitting upright, leaning slightly back |
| Posterior (S2) | Right lateral, leaning slightly forward |
| Anterior (S3) | Supine, flat |
| Superior lingular (S4) | Right lateral, foot of bed elevated 15°, rotate slightly backward |
| Inferior lingular (S5) | Right lateral, foot of bed elevated 15°, rotate slightly forward |
| Superior/Apical — Lower lobe (S6) | Prone, flat |
| Medial basal (S7) | Right lateral, foot of bed elevated 20° |
| Anterior basal (S8) | Supine, foot of bed elevated 20° |
| Lateral basal (S9) | Left lateral, foot of bed elevated 20° |
| Posterior basal (S10) | Prone, foot of bed elevated 20° |
Key Clinical Points
- Apical segment of lower lobe (S6) is the most dependent segment in the supine position → most common site of aspiration pneumonia and foreign body lodgement in supine patients
- Basal segments are most dependent in the erect position → most common sites of lobar pneumonia
- Postural drainage of right lung: placing patient in left lateral decubitus causes secretions to flow from the right bronchial tree toward the carina, stimulating the cough reflex and facilitating expectoration
- The procedure is most effective when combined with chest percussion and vibration (physiotherapy)