New device clears mucous in patients who cannot cough

[antiquity]

HEALTH SCAN: 'Vaculator' sucks up phlegm
Judy Siegel-Itzkovich

(April 4) - It sounds like a Rube Goldberg contraption, but a device that combines the mechanism of an ordinary vacuum cleaner and a ventilator - designed by a doctor and colleagues at Jerusalem's Alyn Hospital for children and teenagers suffering from Duchenne muscular dystrophy (DMD) - is in fact a serious device for clearing phlegm in patients who cannot cough it up.

Called a "vaculator," it has since been tested and approved by the Israel Standards Institute, and now has both Israeli and US patents pending. Clinical trials on inpatients at the orthopedic hospital and rehabilitation center for young people began last month, and the initial reports from both patients and therapists have been very positive, says its inventor and director of Alyn's respiratory rehabilitation unit, Dr. Eliezer Be'eri. "It is our hope that this simple, if somewhat surprising, solution to a serious problem - the lack of access to a necessary rehabilitation device - will help many of our patients avoid repeated pneumonia and eventual tracheostomy (making a breathing hole in the trachea)."

Duchenne muscular dystrophy is a common inherited disorder, affecting one out of every 3,000 male babies, making it the second most common genetic disorder after cystic fibrosis. The disease is due to a defect in the structure of muscle, and causes a slowly progressive and inexorable paralysis of all muscles of the body. In contrast to the severity of the muscle disease, however, the patient's mental functioning is usually unimpaired. Gradual weakening of the chest wall muscles (the muscles that expand and contract the lungs), occurs during the victim's teen years. This weakness becomes so severe that by age 20, most Duchenne patients go into chronic respiratory failure. Untreated, DMD is fatal by age 25, primarily due to respiratory infections.

In the early stages of respiratory failure, patients can be stabilized with nighttime ventilation through a face mask, Be'eri says. "Then, as the respiratory weakness progresses, the patient's inability to cough out sputum from his lungs results in repeated episodes of severe pneumonia. Until recently, the standard treatment for DMD patients at this more advanced stage of the disease was insertion of a tracheostomy, so as to facilitate daily suction of respiratory secretions from the lungs and thus prevent infection. This invasive treatment was unpleasant for the patient, unsightly, and associated with many medical and surgical complications - so much so that many patients preferred no treatment at all to a tracheostomy.

Then, in 1993, a new machine called the "inexuflator", became available in the US; it was based on the iron-lung ventilator in which polio patients were put in the 1950s. The machine would inflate the patient's lungs with air to the maximum possible capacity and then rapidly suck the air out of the chest via the mouth. It worked, but the technique was abandoned when the tracheostomy came into vogue because suction through a tracheostomy cannula is so much easier for medical staff to carry out. But the inexuflator, which is usually used daily, is very expensive, costing about $7,000 here, and it is not supplied to DMD patients by their health fund as it was not included by the Health Ministry in the basket of health services because of its expense (a number of families are suing the health funds, especially Clalit Health Services, to get an inexuflator).

"In an attempt to find a real-world solution for our patients, we thought of combining a standard ventilator (which most of our neuromuscular patients receive free-of-charge from their health fund for nighttime face mask ventilation) and using a household vacuum cleaner for suction. The patient would use the ventilator to inflate his lungs for a few seconds, and then, by pushing on a specialized valve mechanism that would activate the suction force of the attached vacuum cleaner, the air could be rapidly sucked out of the patient's chest. We thought that the net result could be identical to that of the inexuflator, at one tenth of the cost," says Be'eri.

Alyn's biomechanical laboratory built a prototype using a cheap vacuum cleaner, and tests under laboratory conditions proved successful. "The new device was easy to operate, and when used on artificial test lungs, it was found able to generate air pressures and airflow rates comparable to those generated by the much more expensive inexuflator.

[SCI-Nurse]

The current version of the inexsuffalator mentioned in the article (used in the US) is the Cough-Assist. We use it on our unit. It is easist to use with those who have a trach. It generally does not replace suctioning, but can be used as a supplement to or even a replacement for quad coughing. It makes suctioning easier as it brings secretions up higher. This was actually first developed for use in polio, not MD.

(KLD)