Postural drainage (PD) is an airway clearance technique that uses gravity to mobilize and drain excess mucus and secretions from the lungs. This method involves positioning the body in various ways to allow gravity to pull secretions from the smaller, peripheral airways into the larger, central airways. From these larger passages, the mucus can be more easily cleared through coughing or huffing. PD is frequently combined with chest percussion or vibration to mechanically loosen secretions and enhance the effect of gravity. The successful and safe application of this technique is generally performed under the guidance of a healthcare professional, such as a physical or respiratory therapist.
Essential Preparation Before Starting
Proper preparation ensures the procedure is both safe and effective. The session should be timed ideally before meals or at least one to two hours after eating to reduce the risk of reflux or vomiting. Many people find performing drainage first thing in the morning beneficial for clearing overnight secretions. Preparing the environment requires having necessary equipment ready, such as firm pillows, foam wedges, or an adjustable bed, to achieve the precise body angles needed.
Hydration is important, as well-hydrated mucus is thinner and easier to mobilize. Have a container and tissues readily available for the collection and proper disposal of expectorated secretions. Before starting, it is crucial to confirm there are no contraindications, which are conditions that make the procedure unsafe.
The procedure should not be performed without physician approval if the individual has certain conditions. The head-down (Trendelenburg) position should be avoided if the person has severe, untreated gastroesophageal reflux or is significantly short of breath.
Contraindications that require caution or physician approval include:
- Unstable head or neck injuries.
- Acute hemorrhage with hemodynamic instability.
- Untreated pneumothorax.
- Severe, uncontrolled high blood pressure.
- Recent neurosurgery or intracranial pressure greater than 20 mm Hg.
- Recent rib fractures, severe osteoporosis, or a recent heart attack.
Specific Body Positions for Drainage
The core of postural drainage involves positioning the body so the specific lung segment needing clearance is oriented vertically above the main bronchus. This alignment allows gravity to assist the movement of secretions toward the trachea. Each position is typically maintained for five to fifteen minutes, allowing adequate time for the secretions to drain. The specific angle of tilt can vary, but generally ranges from 15 to 30 degrees for segments requiring a head-down position.
Upper Lobe – Apical Segments
To target the apical segments of the upper lobes, the person should be seated upright in a comfortable position, often leaning back against a pillow at an angle of approximately 30 to 40 degrees. This slightly reclined position helps align the apical bronchi for drainage. The area for percussion, if used, is over the muscular area located between the collarbone and the top of the shoulder blade on both sides. This position is often well-tolerated and can be done while sitting in a chair or propped up in bed.
Lower Lobe – Posterior Basal Segments
Draining the posterior basal segments of the lower lobes requires the person to lie on their stomach in a prone position with their hips and legs elevated. This is usually achieved by raising the foot of the bed or drainage table by about 18 to 20 inches, creating a downward tilt of roughly 30 degrees. A pillow should be placed beneath the hips for comfort and to help maintain the position. The caregiver applies percussion over the lower ribs on the back, taking care to avoid the spine and the lowest rib area.
Lower Lobe – Lateral Basal Segments
For the lateral basal segments of the lower lobes, the person should be positioned in a side-lying orientation, rotated one-quarter turn forward onto their stomach. The foot of the bed must still be elevated by 18 to 20 inches to create the necessary head-down tilt. To drain the right lung’s lateral basal segment, the person lies on their left side, and vice-versa, with the upper leg flexed over a pillow for stability and comfort. Percussion is then applied over the uppermost portion of the lower ribs on the side facing the ceiling.
Completing the Procedure and Monitoring
Once the designated time for a specific position has elapsed, the person should transition slowly back to an upright or sitting position. This gradual change helps to prevent sudden drops in blood pressure or dizziness, especially after a head-down tilt. The next step involves actively clearing the mobilized secretions from the larger airways, which is often accomplished using the huffing technique. Huffing is a controlled, forced expiration performed with an open throat, mimicking the action of trying to fog up a mirror.
To perform a huff, the person should sit upright, take a slow, deep breath to partially fill the lungs, and hold it for two to three seconds to allow air to get behind the mucus. They then exhale strongly but slowly, with the mouth open in an “O” shape, using the abdominal muscles to squeeze the air out. This forced exhalation moves mucus from the smaller airways to the central airways, and the process is repeated two to three times, followed by a gentle cough to expel the secretions. Any mucus that is coughed up should be collected in the prepared container and properly disposed of, and hands should be washed immediately afterward.
Throughout the entire session, the patient’s response must be carefully monitored, watching for any signs of distress, such as increased shortness of breath, chest pain, or a change in skin color. If the person experiences severe discomfort, lightheadedness, or heart palpitations, the procedure should be stopped immediately, and the person should be returned to a comfortable, seated position. Following the drainage and clearance of secretions, a brief period of rest is recommended, as the entire process can be physically tiring.