04 - A Commentary on Asthma Management
Investigation of asthma in children - Emergency treatment - General Management  of Asthma

Everybody knows that if you swallow your drink the wrong way you immediately reject it by coughing, because this is the normal defensive reaction to getting fluid in the respiratory system. In a person with chronic allergic asthma the bronchial tubes become very irritable and twitchy. The muscles which surround the tubes contract in response to specific inhaled allergens, and also non-specifically to air pollution, compressing the tubes and making the airway much narrower. This is an exaggeration of the normal defensive reaction to fluid or a crumb going down the wrong way. Bronchodilator drugs such as Ventolin (salbutamol) cause immediate relaxation of these muscles for a few hours, and long-acting bronchodilators such as Serevent (salmeterol) are effective for twelve hours, thus preventing night-time attacks of asthma .

Inhalation of an allergen to which the bronchi are allergic results in swelling of the wall of the bronchus and the secretion of many inflammatory cells and thick mucus which make the airway much narrower, and sometimes plugs up the bronchus altogether. The propellant CFC liquid gas in ordinary steroid inhalers contains a suspension of tiny particles of the drug which, when inhaled, settle on the walls of the bronchi to suppress the allergic reaction taking place there. However, it has been shown by using radioactive aerosols that the particles of steroid from the suspended steroid drug reach only the larger bronchi, and do not reach the smallest bronchi.

Our bronchi resemble a tree upside down, so the trunk is the trachea and one main bronchus goes to each lung, which then branches and re-branches until the bronchi are like tiny twigs leading to the leaves which represent the alveoli where the oxygen is absorbed from the air into the blood. Obviously there are many more tiny twigs than there are big branches

 

Qvar--- A Significant Breakthrough in Steroid Aerosol Technology

Recent developments in aerosol technology to find an alternative to ‘CFC’ aerosols containing chemicals which are destroying the ozone layer have resulted in dissolving the steroid drug in a new Hydro-flouro-alkane propellant gas in the aerosol can, instead of being particles suspended in the liquid CFC gas, so that is has to be shaken before use. The result is that the new aerosol produces really tiny particles of the steroid drug as small as one micron which have been demonstrated to penetrate right down to the smallest bronchial tubes.

The importance of this development is that up to the present time the particles of steroid drug produced by CFC aerosols have been comparatively large, hence able to reach only the larger bronchial tubes, but now these micro-aerosols have been shown to reach the smaller bronchi. This is of great potential importance because it means that for the very first time the whole lung can be being treated by inhaled steroid aerosols.

Unfortunately these aerosols are not yet in general use because most doctors in the UK have never heard of this important development in treatment, although Qvar has actually been prescribable on the NHS for at least three years. However, all CFC aerosols are being phased out anyway, and all aerosols for asthma are changing to this system. This is not because this development enables the smallest bronchi to be treated for the first time, but because of the effect of CFCs on the ozone layer!

 

The Importance of Investigation of Childhood Asthma

The prevalence of Asthma continues to increase year on year, allergies are more important as a cause of asthma and eczema in children than in adults, and many severely asthmatic children will grow up into asthmatic adults. When asthma is allowed to become chronic permanent changes will eventually become established by ‘remodelling’ of the bronchial tubes whereby the walls become thicker and stiffer. Even if the cause is identified and avoided completely it will be a long time before the irritability of the bronchi will cease, hence ‘remodelling’ may be irreversible. More or less effective suppression of the allergic inflammation in the bronchi with drugs is usually the only treatment in the UK today. This inadequate therapeutic approach will inevitably lead to an increase in numbers of chronic asthmatic adults.

It is surprising how few Paediatricians, who specialise in children, do not seem to be interested in finding out why their hospital wards are crowded with wheezing children. Asthmatic children often do not get better spontaneously at age seven or fourteen years, yet parents may still be assured that they will do so. . Even those children who lose their asthma in adolescence quite often relapse in later life. Even when asthma is effectively suppressed with drugs these children are still becoming permanently programmed to respond to common allergens such as dust mite.

This is because the allergic reactions in the bronchi are only suppressed, not stopped altogether.. This also means that even if these allergy victims are properly investigated and their allergies sorted out after they have grown up into adults, the prospect of really significant improvement is less than it would have been if they had had proper investigation and treatment when they were young and completely reversible. This suggests that in future the numbers of established chronic asthmatics will increase, unless the allergic factor is properly dealt with in childhood, not in adulthood when it may be too late.

 

Emergency Treatment of Asthma

If many bronchi become semi-blocked or blocked it is obvious that no inhaled steroid aerosol can possibly reach the bronchi to suppress the reaction, and broncho-dilators to relax the bronchial muscles also become ineffective. The narrower the bronchi the fewer inhaled steroid particles and broncho-dilators can reach the bronchial lining, so the asthma becomes out of control, thus developing a vicious circle. Hence there is clearly a point where inhaled treatments become more and more useless. It is very important that the patient realises this by checking with the peak flow meter, does not persevere with inhaled treatment only, does seek urgent medical advice, or has a supply of oral steroid to take in an emergency. Because chronic asthmatics become accustomed to their condition they can easily underestimate the severity of their asthma. Asthma can be much worse than it seems to be so it is essential to check with a peak flow meter , which should be possessed by every serious asthmatic

In my opinion, and that of most consultant physicians nowadays, all patients with unstable asthma liable to severe attacks should have a supply of steroid tablets in their possession at all times so that they can take up to 40 mgms of prednisolone or equivalent corticosteroid drug at once when necessary, especially if there is any difficulty in obtaining medical help or advice.

Delay can be dangerous, as many deaths from asthma have been found to be due to not having steroids soon enough. The commonest cause of death was not getting oral steroids at all because the severity of the asthma had been underestimated by patient and/or doctor. In my experience this aggressive steroid policy has never caused problems, but delayed giving of oral steroids has produced many serious situations and deaths.

In my long experience short-term high dose steroids, even 40mgms prednisolone a day or more for as long as three weeks, has never caused significant side-effects. The steroid tablets are absorbed into the bloodstream to reach the lining of the blocked and semi-blocked bronchi to dissolve the cells and sticky mucus from beneath the bronchial lining. After some days on a high dose the steroids should open up the airway so that the oral steroids can be phased out and the inhaled steroid can once more reach the bronchi and keep the asthma under control again.. It is the indefinite duration oral steroids that cause side-effects. Even then low doses of oral steroids for many years do not always cause troublesome side-effects

The steroid usually prescribed is prednisolone which has been enteric coated to prevent the drug dissolving in the stomach and causing ulcers, but I have seen only one bleeding ulcer from steroids since 1956. The red enteric coating on the prednisolone tablets is intended to delay the absorption of the tablet until it reaches the intestine, avoiding liberating the drug in the stomach. In occasional cases I have found that this coating prevents absorption altogether just when it is most needed and the tablets literally go down the drain. In some patients 40mgms of enteric coated prednisolone per day for weeks had been totally ineffective, and in two instances admission for intensive care was required.

My preferred steroid for many years has been Betnesol ( betamethasone phosphate) because it dissolves in water, can be well diluted in any fluid to prevent any gastric irritation, is absorbed almost as fast as an intravenous injection, and is much more acceptable than tablets for children. In the few cases who had not responded to large doses of enteric prednisolone the administration of this soluble steroid caused dramatic improvement in only a few hours, but surprisingly this soluble steroid it is largely unheard of and is very seldom prescribed. Unfortunately this steroid contains erythrosine dye which is quite unnecessary and can cause problems in some patients, but because of regulations it would entail much red tape and expense to alter the formulation, and allergy to this dye is very uncommon.

 

General Management of Asthma

Full instructions on avoidance of the common causes of asthma and guidelines for treatment are freely available today from many sources, and should be in full operation in any medical practice where there is a special asthma clinic, so there would be little point in repeating them here. This has gradually come to pass over the years, and has led to a great improvement in management.

The stressed GP has neither time nor the knowledge to investigate asthma, but the nurse specialist has the time, has a special interest, and should be able to carry out skin testing, although this is still uncommon. Advice on the importance of pets in causing allergies is seldom pursued as vigorously as it should be and advice on avoidance not taken seriously, or ignored The main role of the nurse specialist is to make sure the patients use inhalers and peak flow meters properly, and have a management plan.

Measures to reduce the dust mite, the most common cause of asthma, chronic rhinitis, and eczema, are difficult and expensive. Powerful and expensive vacuum cleaners are advocated for the removal of the mites, but cannot drag the mites out from the depths of the carpets. In recent times the availability of affordable laminated flooring to replace the fitted carpets which have been an ideal home for mites for many years has been very helpful. Special mite-proof covers for mattress and pillows are helpful, but expensive.

Pillows with synthetic fibre stuffing have been sold as ‘anti-allergenic’ for many years, but have recently been clearly proved to accumulate a huge mite population in a few months, much worse than the down pillows doctors have been advising patients to throw away!. This is because down pillows have finer woven covers which are less permeable for mite faeces, and of course they are much more comfortable.

There is no doubt that a very large and lucrative market has grown up in selling all these measures to fight the mite, and that most people know that the mite is a major problem for allergy, but the results are often disappointing. My personal experience with Acarosan to kill off the mites for up to a year after one application is another story which will be told in a special section of this website.

Steroid Phobia and unreasonable fear of side-effects is very common, but except for unavoidable long-term use of oral steroids, when the side-effects can be regarded as the price that has to be paid for the beneficial effects of the drug, these fears are grossly exaggerated. Inhaled steroids for asthma , such as Becotide, Pulmicort, Budesonide, Flixotide, Qvar, and others, and also steroid nasal sprays, rarely cause any problems except for occasional thrush. Many children who attended my clinic started using Becotide from 1970, when they took part in the very first trials, and are still using it daily without problems over thirty years later.

When chronic asthmatics become pregnant there is often fear of side-effects on the foetus which are quite unfounded. I will never forget a patient who died of asthma because the obstetrician who was looking after her did not ask my advice and withheld steroids until it was too late. It seems glaringly obvious that lack of oxygen due to the asthma is much more likely to harm the foetus than steroids, yet there are still misgivings by both doctors and patients about steroids in pregnancy.

Steroid phobia also applies to inhaled steroids, steroid creams, and other steroids which are applied locally to the part of the body which requires treatment. It takes years to produce thinning of the skin and bruising from using creams, and local applications hardly ever cause generalised effects unless used very excessively.. Unfortunately patients may not use their inhalers or creams for fear of side-effects and even withhold these treatments from their children with asthma or eczema. It seems that these concerns are seldom explained to patients, who may not ask for advice during a hurried consultation.