by Warren P. Silberstein, M.D.
06/30/97
The main equipment used in the home management of asthma serves to deliver aerosol medication for inhalation. Theses medications include rescue medications and maintenance medications.
Nebulizers
Generally, to treat infants with inhaled medications a nebulizer has to be used. A nebulizer is a special container into which liquid medication is placed. The container is attached by tubing to an air compressor or oxygen tank. The air or oxygen going through the nebulizer makes a fine mist which can be inhaled. This can be done by holding the nebulizer in front of the patient's face. A mouthpiece can be attached to the nebulizer so that older children (and adults) can inhale the medication directly from the nebulizer. A mask can be attached to the nebulizer to direct the medication at an infant's or younger child's nose and mouth. Many infants object to the mask being held on their faces because they don't understand but if these infants use the nebulizer regularly, they get used to it. Many of my younger patients are uncooperative with nebulizer treatments when they feel well because treatments take up to 15 minutes. Those same children become cooperative with the nebulizer when they are wheezing because they have learned that it makes them feel better.
Most home nebulizers are used with a compressor rather than oxygen. As a result, most patients refer to the entire package - nebulizer, compressor, and tubing - as a nebulizer. The nebulizer delivers the medication in a fine mist over 15 minutes. As a result, it isn't necessary for the patient to hold the medication in his lungs or coordinate his breathing with the delivery of medication. This not only makes the nebulizer the ideal equipment for treating infants and young children, but it is also the best way for an older child or adult to treat severe wheezing.
The disadvantages of using a nebulizer include the long time commitment for maintenance treatments and lack of portability. Four treatments a day would mean approximately an hour a day using the nebulizer. I can remember traveling with my daughter when she was younger and having to find a place to plug in her nebulizer for treatments. Nebulizers are available with battery packs, but they certainly can't be carried around as conveniently as a spray.
One caution for all patients who have nebulizers: The nebulizer is the same equipment that is used in the doctor's office or emergency room for treating asthma attacks. That essentially gives patients who own nebulizers the ability to treat themselves intensively rather than seeking medical attention; however, if asthma symptoms are escalating, it is dangerous to keep taking more nebulizer treatments without seeking medical attention. The danger lies not in the side effects of the medicine, but rather, in the delay in seeking medical attention. The same caution applies to rescue medication sprays. Because they relieve symptoms so well, some patients use increasing amounts of spray to treat escalating symptoms rather than seeking medical attention. Such action is extremely risky because by the time these patients seek emergency treatment there asthma is much more difficult to control.
Treatment with nebulized medications is not a last resort reserved for desperate situations. Inhaled medications are the best treatments for asthma. They work well, quickly, safely, and generally have fewer side effects than medications taken by mouth. When infants require maintenance medication, the nebulizer is the way to go. However, even though some parents may feel that they would like a nebulizer in order to avoid an emergency visit, nebulizers are not appropriate for patients with occasional symptoms. Since the parents of mild asthmatics have little experience using the nebulizer they are not equipped to make judgments about treatment and are better off seeking medical attention when their child has increased symptoms.
Sprays (also known as Metered Dose Inhalers or MDIs)
Most people think of rescue medications when they think of sprays; however, many excellent maintenance medications also come as sprays. Whether an asthmatic is taking a rescue medication or a maintenance medication proper technique for using the spray is of utmost importance. In order for the spray to work it must coat as much of the airways as possible.
When using a spray an asthmatic should follow these steps:
hold the spray in front of an open mouth (alternative)
If the dose of medication is more than one spray steps 1 through 5 should be repeated each time. When taking more than one spray, if the patient is wheezing he should wait several minutes before taking the second spray of rescue medicine to allow the airways to open up a bit increasing the effectiveness of the second dose. If coughing prevents him from holding the medicine in his lungs, the dose should not be counted as taken. He should wait a few minutes to allow the little bit of spray coating the airways to decrease the airway irritability and then try again.
Sprays are very effective medications. Once a child learns how to use a spray (with or without a spacer), sprays are preferable to syrups and pills for rescue treatments even for occasional symptoms. If you speak to an older asthmatic he may have a completely different impression of sprays because years ago there were no maintenance sprays and the rescue sprays had more side effects and a short duration of action. As a result, asthmatics were cautioned to use these sprays only as a last resort.
Spacers
A spacer is a device placed between the spray and the patient's mouth. A simple spacer can be made by poking a hole into the bottom of a styrofoam cup, placing the mouthpiece of the spray into the hole, and placing the cup over the mouth (or mouth and nose) to take the spray. Studies show that spacers increase the amount of medicine that gets into the lungs and decrease the amount deposited in the throat even in adults who have good spray technique. That increases the effectiveness of the spray and decreases the risk of thrush from steroid sprays.
A spacer makes it less necessary for a child to coordinate his breathing with spraying since the spray can be released into the chamber of the spacer and then the child can breathe it in. For greatest benefit the spray still should be breathed in slowly and deeply and held in the lungs. Many available spacers have a horn that honks if the child breathes in too quickly. Unfortunately, many children like to make their spacer honk.
When using any spacer don't forget to shake the spray first. After the spray is inserted into the spacer, the child puts the mouthpiece of the spacer into his mouth. Once he has the spacer in his mouth the medicine can be sprayed and the child can breathe in. If possible, he should breathe in as the spray is released, but it's not crucial. Then he should hold the spray in his lungs as long as possible.
For young children, I prefer the Inspirese. To use an Inspirese the spray canister has to be removed from its sleeve and placed into the slot in the Inspirese. The Inspirese has a collapsible bag. It should be expanded before spraying the medication, preferably by having the child breathe out into the Inspirese. Then the medication can be sprayed as seen in the first diagram.
After the medication is sprayed into the Inspirese, the child should breathe in steadily collapsing the bag as seen in the second diagram.
There are many spacers similar to the Aerochamber pictured here. They are simple tubes into which the spray can be inserted. Once the spray is inserted into the spacer and the child has the mouthpiece in his mouth, the medication can be sprayed into the chamber and the child can breathe it in. Several spacers, including the Aerochamber, are available with a mask making it possible for even younger children to use them. The effectiveness of these devices is limited by the young children's ability to breathe the medication in properly and then hold it in their lungs; however, if the mask is held over the infant's face for several breaths, a reasonable quantity of the medication should be delivered to the infant's lungs.
Peak Flow Meter
A peak flow meter is a device that can give an objective measure of an asthmatic's respiratory status. To use it, the asthmatic must take a deep breath, place the mouthpiece into his mouth, close his lips around it, and blow out as hard as he can. The blow should be all the air at once rather than a long blow. It takes practice to learn the technique. The more a child does it, the more reliable the readings will be.
There are standards for normal peak flow rate (PEFR) values based on size, but it is more important to know what a child's personal best reading is. PEFRs don't always correlate with an asthmatic's symptoms because they measure resistance in the larger airways better than in the smallest airways. But as a general rule, if an asthmatics PEFR falls consistently below 80% of his personal best, it tells you that trouble is brewing. This is particularly useful in helping parents to recognize the early signs of asthma when the patient is coughing but may offer no complaints. Since anyone can cough, a low PEFR can help to determine that the cough may be asthma related and the parent knows to start or increase treatment, or call the doctor. PEFR readings below 50% of the personal best indicate trouble and a need for medical intervention.
PEFR readings can also be used to monitor treatment including monitoring the response to bronchodilators. When PEFRs rise significantly after treatment it indicates not only a good response, but also a need for continuing treatments. When PEFRs are low and patients have asthma symptoms, if the PEFR doesn't rise in response to rescue treatment it indicates a need for greater medical intervention.
When patients use peak flow meters at home it is easier for a physician to manage their asthma over the telephone because the physician can use the readings to follow the patient's progress and make therapeutic decisions without seeing him. The PEFR can also be used to determine if a patient should be seen. If patients take peak flow readings regularly and record them in a log, it provides an objective measure to accurately assess the patient's long term management.
NebulizersFinal article in series: An Overview of the Management of AsthmaUse and Care of a NebulizerSpacers, Sprays, AutohalersMovie File - video clip of child using nebulizer. Long download.
American Allergy Supply Compressor Nebulizer Page - Pictures and descriptions of several brands of nebulizers and compressors available for sale at this site.
Spacer Devices - good pictures of Aerochamber and Aerochamber with Mask.Peak Flow MetersDrug Delivery Devices -spacer, MDI, autohaler
Peak Flow Meters - Pictures and descriptions of several brands of peak flow meters available for sale at this site.
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