How Do Health Care Professionals Diagnose Asthma?
If you go to the emergency department for an asthma attack, the health care provider will first assess how severe the attack is. Attacks are usually classified as mild, moderate, or severe. This assessment is based on several factors:
- symptom severity and duration,
- degree of airway obstruction, and
- the extent to which the attack is interfering with regular activities.
Mild and moderate attacks usually involve the following symptoms, which may come on gradually:
- chest tightness,
- coughing or spitting up mucus,
- restlessness or trouble sleeping, and
Severe attacks are less common. They may involve the following symptoms:
- difficulty talking,
- tightness in neck muscles,
- slight gray or bluish color in your lips and fingernail beds,
- skin appear "sucked in" around the rib cage, and
- "silent" chest (no wheezing on inhalation or exhalation).
If you are able to speak, the health care provider will ask you questions about your symptoms, your medical history, and your medications. Answer as completely as you can. He or she will also examine you and observe you as you breathe.
If this is your first attack, or the first time you have sought medical attention for your symptoms, the health care provider will ask questions and perform tests to search for and rule out other causes of the symptoms.
Measurements of how well you are breathing include the following:
- Spirometer: This device measures how much air you can exhale and how forcefully you can breathe out. The test may be done before and after you take inhaled medication. Spirometry is a good way to monitor your lung function, but this forced maneuver during an attack can worsen your symptoms. This test is a more accurate measurement of your baseline lung function.
- Peak flow meter: This is another way of measuring how forcefully you can breathe out during an attack. This is a useful tool for monitoring the severity of an attack as well as the adequacy of maintenance therapy. It is a less forceful maneuver and therefore can be used during an attack.
- Oximetry: A painless probe, called a pulse oximeter, will be placed on your fingertip to measure the amount of oxygen in your bloodstream.
There is no blood test than can pinpoint the cause of asthma.
- Your blood may be checked for signs of an infection that might be contributing to this attack.
- In severe attacks, it may be necessary to sample blood from an artery to determine exactly how much oxygen and carbon dioxide are present in your body.
A chest X-ray may also be taken. This is mostly to rule out other conditions that can cause similar symptoms.
If your asthma has just been diagnosed, you may be started on a regimen of medications and monitoring. You will be given two types of medications:
- Controller/maintenance medications: These are for long-term control of persistent asthma. They help to reduce the inflammation in the lungs that underlies asthma attacks. You take these every day regardless of whether you are having symptoms or not.
- Rescue medications: These are for short-term control of asthma attacks. You take these only when you are having symptoms or are more likely to have an attack -- for example, when you have an infection in your respiratory tract. Some feel that the term rescue medication means that you only use it in an emergency. Actually, these medications should be used for any asthma symptoms, like cough, wheezing, chest tightness, or shortness of breath. They can also be used in anticipation of an activity that causes shortness of breath. It is important to keep track of the frequency that these inhalers are used for unplanned symptoms (that is, not when used in anticipation of symptoms for an activity). Asthma is considered well-controlled when rescue therapy is used less than five times per week. If asthma is not well controlled, then your provider can add additional medications. This concept is important because it helps in overall control and patient understanding of their asthma management. As is described below, medication can be added (step-up therapy) when rescue inhaler use increases for a period of time. Similarly, medications can be reduced (step-down therapy) when rescue use is minimum or nonexistent.
Your treatment plan will also include other components:
- awareness of your triggers and avoiding the triggers as much as possible;
- recommendations for coping with asthma in your daily life;
- regular follow-up visits to your health care provider; and
- use of a peak flow meter.
At your follow-up visits, your health care provider will review how you have been doing.
- He or she will ask you about frequency and severity of attacks, use of rescue medications, and peak flow measurements.
- Lung function tests may be done to see how your lungs are responding to your treatment.
- This is a good time to discuss medication side effects or any problems you are having with your treatment.
The peak flow meter is a simple, inexpensive device that measures how forcefully you are able to exhale.
- Ask your health care provider or an assistant to show you how to use the peak flow meter. He or she should watch you use it until you can do it correctly.
- Keep one in your home and use it regularly. Your health care provider will make suggestions as to when you should measure your peak flow.
- Checking your peak flow is a good way to help you and your health care provider assess what triggers your asthma and its severity.
- Check your peak flow regularly and keep a record of the results. Over time, your health care provider may be able to use this record to determine appropriate medications, reducing dose or side effects.
- Peak flow measures fall just before an asthma attack. If you use your peak flow meter regularly, you may be able to predict when you are going to have an attack.
- It can also be used to check your response to rescue medications.
Together, you and your health care provider will develop an action plan for you in case of asthma attack. The asthma action plan will include the following:
- how to use the controller medication;
- how to use rescue medication in case of an attack;
- what to do if the rescue medication does not work right away;
- when to call the health care provider; and
- when to go directly to the hospital emergency department.