Patients with cystic fibrosis (CF) performing airway clearance (AC) daily to remove secretions are faced with a broad array of devices and techniques to aid in this process and little to guide them in making an informed choice. Two of the most common approaches are chest percussion and use of high frequency chest wall compression (HFCWP) vests. Until recently, there has been very little evidence to indicate that one technique is superior to the other. However, recent research conducted at the Stanford University Cystic Fibrosis Center in Palo Alto, California (http://cfcenter.stanford.edu) offers significant insights.
The research, led by principal investigators Carlos E. Milla, MD (http://Med.Stanford.edu/profiles/Carlos_Milla.edu) and Colleen Dunn, RRT (http://cfcenter.stanford.edu), sought to determine whether AC treatment with either chest percussion combined with postural drainage or HFCWP vests were preferred for performing chest physical therapy (CPT). These are two very different treatments.
Traditional AC that combines manual percussion with postural drainage is a standard form of therapy. The objective is to dislodge congestion that can be coughed out. Even though this is the oldest form of therapy, no other approach has proven to be superior. However, manual percussion is time and labor intensive; it is tiring, and generally requires a therapist or trained individual to perform applications on a patient’s back. Chest percussion aided by a percussive device can vastly reduce their time and labor demands.
By contrast, high-frequency chest wall compression is comprised of an inflatable vest connected to a compressor that causes the vest to inflate and deflate against the thorax creating an oscillatory motion. The vibratory shear forces reduce the viscosity of secretions similar to the way shaking jello will liquefy it.
The Stanford study sought to determine which is the most effective of these two approaches for performing CPT by comparing:
- Sputum production during the sessions,
- Changes in pulmonary function after each session, and
- Differences in comfort level and tolerability using a standardized survey instrument.
The methodology involved a randomized study of 15 CF patients between the ages of 15-35 years. Although the patients were administered supervised treatments, they also were required to have a regular home therapeutic regimen performed at least 2 times daily. They were further had to have stable lung functions in which the FVC and FEV1 were greater than 40%.
The Stanford Research used the Med Systems Electro Flo® 5000 and a vest for their comparison. The findings were presented at a June 13-14, 2013, 36th European Cystic Fibrosis Conference in Lisbon, Portugal and summarized on the Med Systems web page (www.medsystems.com) as an Abstract titled “Comparison of Acute Effects of Conventional High Frequency Chest Wall Oscillation and the Electro Flo® 5000 Airway Clearance Devices in Cystic Fibrosis Patients.” The results showed that both devices were well tolerated by the patients, and both were comparable in their efficacy in promoting sputum mobilization.
Since they are comparable in a research setting, doctor and patient preferences are important considerations when deciding what to use. This is consistent with the position taken by the California Thoracic Society in their white paper titled:
“Airway Clearance Devices: Limited Evidence for What Is ‘The Best Method.’”¹
That is, a young person under 50 pounds and a person with a condition that limits their ability to conduct vigorous chest percussion may find the vest preferable. However, someone else seeking a stronger form of therapy may choose the Electro Flo® 5000 with its Force Multiplying Technology consisting of 30 targeted setting options. Research published in the journal Respiratory Care draws a clear relationship between higher pressure during CPT and greater relief among cystic fibrosis patients.²
Combined with the Self-Administrator®, a strap for securing the Electro Flo® 5000 power head, a patient may direct therapy to individual lobes on the back as needed. In contrast to vests which are heavy and bulky, the Electro Flo® 5000 is light weight, and easily portable so patients can use it wherever they choose. A further consideration is that the Electro Flo® 5000 costs significantly less than a vest.
Given both the research findings, and knowing about the benefits of the Electro Flo® 5000, patients now have a solid basis from which to determine the best means for managing their CF airway clearance needs.