Post-Polio Health (ISSN 1066-5331)
Vol. 6, No. 3, Summer 1990
G.T. Spencer, FFARCS, (retired) London, England
*Note: This was the second of two papers presented by Dr. Spencer at the International Symposium on Poliomyelitis in Munich on April 7-9, 1988.
There are at least ten different methods of treatment for underventilation following poliomyelitis, and the method selected must not only be fully effective medically, but also socially acceptable and practical in the home. In practice, all methods can be and are used in the home and I think the best thing I can do is to list each method with a brief summary of the advantages and disadvantages.
Tracheostomy and Intermittent Positive Pressure Respiration: This is normally used by people who need mechanical respiratory assistance both by day and by night and is probably the best method for patients with very severe muscular paralysis. Its advantages are that it is exceedingly effective, can be provided by relatively simple equipment which is small and convenient and can be attached to or incorporated in wheelchairs. Its disadvantages lie mainly in the tracheostomy that is always a route for the introduction of infection, can erode surrounding structures, and prevent glossopharyngeal breathing without an attendant being present to occlude the tracheostomy. Tracheostomy tubes can become blocked; speech is possible with a non-cuffed tube, but it is intermittent during the inspiratory stroke of a respirator. Some patients who would undoubtedly benefit by it are reluctant to undergo tracheostomy because they feel that it increases their disability, makes them look even less like a normal person, and prevents, for example, the wearing of a collar and tie which, even in these days, many believe to be part of being properly dressed.
Iron Lung or Tank Ventilator: This is also a reasonably efficient form of artificial ventilation. Its use is normally only justified for people who need artificial ventilation by night as well as for all or some of the day. Modern iron lungs, such as the Cape Alligator or Rotator, are quick and easy to get into and out of, and we have recently designed and made one in which self-insertion and release are possible for people with reasonable strength in their arms. The disadvantages of the iron lung are fairly obvious: it is very large in size and once inside a nonself-release tank, the user is effectively trapped and needs an attendant to be released. Nor is it easily portable for overnight stays from home.
Mouthpiece Intermittent Positive Pressure Breathing: This technique has become increasingly popular in recent years and a large variety of mouthpieces which stay in place during sleep have been developed. It is adequate for those with moderate respiratory weakness, but some of the more severely paralysed find that they can only use it for a limited number of nights in succession and need to resort to alternative devices from time to time. The equipment is small and easily portable, though the technique requires some practice and trial and error before it can be regularly used.
Nosepiece Intermittent Positive Pressure Breathing: This is similar to the mouthpiece method and may have advantages in that it is less likely to produce obstruction of the upper airway. Development of adequate nasal masks is still continuing and many can easily produce soreness and discomfort over the bridge of the nose.
Pneumobelt: This is the only method which works by augmenting expiration. It is not particularly efficient and consists of a belt applied around the abdomen and lower chest that is intermittently inflated thus squeezing air out of the lungs. It is suitable only for people with paralysed abdominal muscles and diaphragm who need to use it during the daytime when sitting up. They usually need something more efficient at night. The equipment is small and the pump can be attached to a wheelchair. When used over long periods, there is some evidence that it produces damage to the lower parts of the lung.
Protriptyline: This is a relatively new drug which can be taken in pill form on going to bed. It acts by reducing the length and frequency of periods of Rapid Eye Movement sleep. This is a particular type of sleep that occurs in most people during which breathing is most disturbed. It is only effective for people with relatively mild underventilation and is particularly suitable for people with congenital or non-paralytic scoliosis. It has the great advantage that no equipment is required, but, unfortunately, the drug has quite serious side effects, producing constipation and dryness of the mouth. It can also cause temporary impotence in sexually active men. In general, it is rarely suitable for people with poliomyelitis, many of whom have a distressing tendency to constipation anyway.
There is no doubt that all these different methods have a place and an adequate medical centre should have them all available and be able to select whichever one, or combination of several, is most suitable and effective for each individual. Unfortunately, equipment manufacturers prefer making large numbers of one or two types of machines rather than small numbers of a variety and, at present, adequate designs of all these devices are only available in a few countries.