How Severe Is Your Asthma?

While it may be true that under the right circumstances any asthmatic can have a severe attack, most asthmatics have relatively consistent symptoms. One asthma attack usually doesn't vary much from the last and many asthmatics improve over time. There are several ways to gauge the severity of your asthma. The first and easiest way is to ask your doctor. Because asthma is an exceptionally common condition, many doctors have significant experience treating it and are thereby capable of determining its severity.

 

 

You can personally estimate the severity of an attack, and hence the severity of your asthma, by using a peak flow meter. Asthma attacks are graded from mild to moderate to severe, and severity is calculated by comparing Predicted Peak Flow (PPF) or Best Peak Flow (BPF) to current peak flow. Keep in mind that peak flow readings are effort dependent, so always give your best shot or else the reading may not be accurate. If you hold back on how hard you blow or don't use proper technique, you can make a mild attack seem, at least according to the peak flow meter, like a severe attack. You may think no harm is done, but imagine the psychological impact on the mild asthmatic whose peak flow meter is telling them it's time to call 911. So, whenever you whip out your peak flow meter, make sure you give it your best shot.

 

It's always a good idea to have your peak flow technique observed by a healthcare professional to make sure you're using the meter correctly. Also, when visiting your doctor, always bring your asthma journal with peak flow recordings. Allowing your physician to see the numbers, rather than just telling him or her about the numbers, is absolutely critical to helping your physician make informed decisions.

 

A peak flow meter is like a little doctor's office you can carry in your pocket that measures how much air you can exhale from your lungs. For an asthmatic, this measurement depends on whether or not you're having symptoms. Peak flow drops during an asthma attack and rises to normal once the attack is over. Peak flow meters are small, inexpensive, and your doctor may have already given you a free one. You should also keep an asthma journal, a diary that will help you keep track of your peak flow measurements and monitor your asthma symptoms. Even more important, your asthma journal is going to help you get rid of your asthma. One of the best ways to determine the severity of an asthma attack is to measure your peak flow and compare this reading to your Best Peak Flow (BPF).

 

The peak flow meter has two ends, one end you blow into and one end through which the blown air escapes. Traveling between the two ends, the air moves a spring-loaded piston attached to an indicator that records your peak flow in liters per minute (L/min). Here's how to use a peak flow meter:

 

 

 

 

 

 

Comparing present peak flow to BPF is a more accurate reflection of how well or poorly your asthma is doing. To determine your BPF, take two or three peak flow readings daily when your asthma is stable. Record these peak flows after you wake up and in the early afternoon between noon and 2 P.M. You should also record your peak flow before and after using a short-acting beta-agonist like albuterol. After you have accumulated two to three weeks of readings, ask your physician to review the numbers to determine your Best Peak Flow. Your BPF will usually be your highest peak flow reading. If you've just returned from the closet and are dusting off your old peak flow meter, don't be surprised if your BPF is lower than several years ago, as peak flow naturally declines with age. Hence, most authorities recommend that you determine your BPF every six months.

 

We are interested in comparing your most recent BPF to your peak flow during an asthma attack. You can measure the severity of an asthma attack by taking a peak flow reading during the attack and calculating the percentage change from BPF. Let's calculate a sample percentage change in peak flow following the simple formula, Severity of asthma attack equals current peak flow divided by Best Peak Flow. If your BPF is 700 L/min and you're now blowing 550 L/min, how bad is this attack? Divide current peak flow by BPF: 550/700 = 0.79 (79 percent). During this attack, your current peak flow represents 79 percent of your BPF. You are having a mild asthma attack.

 

Like a traffic light, asthma severity is divided into green, yellow, and red zones, otherwise known as the PEF (Peak Expiratory Flow) Zone system:

 

 

After inhaling a beta-agonist, you should ideally see a 20 percent increase in peak flow. For instance, if your BPF is 500 and you are now blowing 350, you are within 60 to 80 percent of your BPF and are in the yellow zone. If, however, you are blowing 240, your current peak flow is less than 60 percent of your BPF and you are in the red zone.

 

Most physicians will recommend that you take routine daily peak flow measurements even when you're feeling well. Multiple peak flow measurements track baseline lung function and can detect airway narrowing hours to days before an attack, allowing for early intervention prior to symptom development. Talk to your healthcare professional about how your peak flow meter can detect an attack before symptoms occur.

 

There are exceptions to every rule, but in most cases measuring your peak flow is an excellent way to follow the severity of your asthma. The only major problem with peak flow is that the reading you get after you blow into your meter depends in large part on how hard you blow; that is, peak flow measurements are effort dependent. This is why when you measure peak flow, remember to give it your best shot. To get the most accurate reading, it's also important to take three peak flow measurements in a row and, even more important, to know how to use a peak flow meter.

 

 

While peak flow readings give you an idea of the severity of an asthma attack, they don't tell the whole story. To know how severe your asthma is, we have to examine your history because past asthma behavior is often predictive of future asthma behavior. If the majority of your attacks are mild, and you know that over the past ten years one attack never varied much from the next, we can safely say you have mild asthma. The same logic holds for moderate and severe asthma. While most asthmatics have predictable symptoms, the rare subtype brittle asthma is characterized by severe, unpredictable attacks that can occur without warning. If you've ever been diagnosed with brittle or severe asthma, always work with your doctor when changing your medication regimen.

 

A sure sign of severe asthma is a history of intubation, being put on a ventilator with a tube down your throat to help you breathe. Intubation immediately puts you in the severe category no matter how well controlled you are today. You may be feeling great right now, but a history of intubation means there's a significant risk of a severe attack. So, if you were ever intubated (or nearly intubated), it is especially important that you work closely with a doctor to get your asthma under control.

 

Another way to appreciate asthma severity involves the number and types of medications you take. If you use only one or two medications, like albuterol and an inhaled steroid, chances are your asthma is mild. If, however, you require four to ten medications, this indicates moderate to severe asthma. Most doctors would also agree that necessary oral steroid use is a warning sign of moderate to severe asthma, with chronic oral steroid use or "steroid dependency" indicative of severe asthma.

 

A history of hospitalization also figures into the asthma severity equation. Having been hospitalized for asthma puts you in the moderate to severe category. Emergency-room visits are more difficult to assess. When evaluating asthma severity, most doctors rely on prior history, medication use, and hospitalization and/or intubation history.

 

If you find that you fall into the severe or brittle asthma category, don't give up. Having severe asthma only means you have to move slower and work more closely with your doctor. Most of this book is devoted to removing asthma triggers and strengthening your body and immune system so they can defend your lungs against the toxic rigors of life. The advice given here is intended for everyone, no matter how mild or severe his or her asthma. The degree of asthma severity will only impact these recommendations by altering how quickly the necessary lifestyle and medication changes can and should be made. Obviously, we can be more aggressive with a mild, stable asthmatic on one or two medications than with a brittle asthmatic who has just been discharged from the hospital and takes ten different medications. No matter what your situation, I recommend you form an alliance with an understanding and trusted doctor who can safely guide you through these changes.