Vol. 15 •Issue 7 • Page 26
Home Pathways
How to Manage Secretions
Respiratory therapists have the solution.
Got sputum? Many patients with an assortment of pulmonary and non-pulmonary diseases do.
The list includes cystic fibrosis, bronchiectasis, pneumonias, ciliary dyskinesia, bronchitis, neuromuscular diseases such as amyotrophic lateral sclerosis, muscular dystrophies, and cerebral palsies, spinal cord injuries, stroke or cerebral vascular accidents, and closed head injuries.
When secretions are retained and patients lack the muscle control to generate a strong cough, they can develop impaired gas exchange, atelectasis, and infections. The good news is respiratory therapists have numerous airway clearance tools to help patients mobilize these secretions. Many of these technologies can be self-administered, giving patients the ability to increase their independence.
Airway clearance techniques (ACTs) are indicated for copious secretions of 25 to 30 mL/day. Symptoms include increased cough with greater shortness of breath. Patients experience a change in vital signs, and the amount of secretions may increase or decrease, as well as change tenacity or color.
Airway clearance devices can be used individually, in combination with two or more devices, or in addition to medicated aerosols. Depending on the disease process, patients use bronchodilators, mucolytics, or antibiotic therapy. These medicated devices are used before and/or during the ACTs depending on the disease.
Cough is crucial
The most important ACT is the cough. Many of us take the ability to cough for granted until we can’t generate one or feel our cough reflex being challenged (i.e., when we inhale and swallow a liquid at the same time).
A cough results when the cough receptors, mostly located in the airways, vocal cords, pharynx, and diaphragm, are stimulated.
Coughing is a protective reflex mechanism that removes secretions from the airways. It’s a coordinated effort between respiratory muscles contracting to generate a deep breath in, followed by closure of the glottis with a rapid increase in pressure within the thorax. After these maneuvers, the glottis opens to move the air, debris, and secretions out of the airways.
Many of the patients with the diseases listed above can’t generate an effective cough, or their cough is too weak to move the secretions out of the airways.
Helpful techniques may include the directed or huff cough which is a series of small coughs or forced expiratory technique. Have patients perform one or two huffs (forced expirations) from mid to low volumes with the glottis open, followed by a relaxation.1
To teach this technique to patients, have them place a cotton ball in the palm of their hand. Instruct them to take a slow, deep breath and then exhale with four or five small huffs to move the cotton ball off the palm. Patients or RTs can reinforce the huff cough with self-compression of the chest wall using adduction movement of the upper arms.1
Chest percussion therapy (CPT) and postural drainage (PD) are common therapies for patients with airway clearance impairment. CPT requires a caregiver to percuss or clap over the chest or thorax with cupped hands while the patient lies or sits in various drainage positions to assist with mobilizing secretions.2
The American Association for Respiratory Care’s clinical practice guideline for PD therapy describes CPT as an “external manipulation indicated when sputum is not mobile and there is a need to assist with the movement of secretions by gravity.”2 The secretions move into the airway and the patient can cough them out, or a suction device can be used.
Mechanical answers
Mechanical percussors are electrical handheld devices used to tap over the chest wall, as the patient lies or sits in the drainage positions. These devices are programmable for speed of the percussion.
The high-frequency chest wall compression (HFCWC) or oscillation devices are a mechanical form of chest percussion. HFCWC uses an air pulse generator to deliver small air pulses through a circuit to an inflatable vest worn by the patient.4 The inflated vest compresses and releases the chest wall about 20 times per second, creating a cough-like response.3
The benefits of HFCWC include all lobes of the lung being treated at the same time so the patient doesn’t have be placed in the eight to 10 varying positions that are needed for CPT and PD.
Positive expiratory pressure (PEP) therapy promotes mucus clearance by preventing airway closure and allows the patient to breathe out against a resistance that can be increased or decreased. The device can be used with a mask or mouthpiece.4
The 2006 American College of Chest Physicians evidence-based clinical practice guidelines advocate the use of PEP over CPT for patients with CF.3 This device can be taught to young children and adults.
A vibratory PEP therapy lets the patient take a deep breath and forced exhalation to clear the secretions in the airway. It combines high-frequency air flow oscillations with PEP. Another manufacturer offers a device that combines PEP and airway vibrations to mobilize secretions. The tool isn’t gravity dependent and may be easier to use.
Intrapulmonary percussive ventilation combines mechanical chest percussion and intermittent positive pressure breathing with high-frequency bursts of air or oxygen into the lungs.3 This device delivers high-flow jets of air into the airways with a pneumatic flow interrupter at a rate of 200 to 300 cycles/minute.3 The combination of the vibrations and pressure loosen the secretions and stimulates a cough. The patient controls the inspiratory time, peak pressure, and respiratory rate.
A mechanical insufflation-exsufflation machine is a portable electric device that incorporates a blower and a valve to alternately apply positive and negative pressure to the patient’s airway. The quick shift in pressure generates a high expiratory flow from the lung that will simulate a cough. This will assist the patient in clearing retained secretions.
Researchers performed a systematic review of nonpharmacologic airway clearance devices between 1960 and 2004.3 They found most studies were primarily limited to CF patients and focused on the short-term effects of these therapies and not the long-term. This lends an area for studies to develop.
It’s important for RTs to become familiar with all types of ACT in order to match patients with the best treatment option. Selecting an ACT is dependant on the patient and the technique associated with the ACT.5 Patient factors include the ability to self-administer, disease type and severity, age, ability to learn, and work required to use the device. Technique factors are clinician teaching skills, cost, equipment required, physician and health care provider goals, and effectiveness of the therapy.5
Donna “De De” Gardner, MSHP, RRT, is assistant professor and director of clinical education, University of Texas Health Science Center at San Antonio.
For a list of references, please call Mike Bederka at 610-278-1400, ext. 1128, or look under the “From Print” toolbar on the left side of our home page at www.advanceweb.com/respmanager
