A 42-year-old man is evaluated in the pulmonology clinic for a follow-up visit for asthma that was diagnosed one month ago. At that time, the patient’s spirometry testing showed an FEV 1 /FVC ratio of 0.6 (normal >0.7) and an increase in FEV 1 of 15% after albuterol administration. The patient was started on a daily low-dose inhaled corticosteroids (ICS) / long-acting beta-agonists (LABA) inhaler and has noticed an improvement in his symptoms. The patient wakes up short of breath several times weekly and needs to use a short-acting albuterol inhaler several times a day. Physical exam reveals diffuse bilateral wheezing. High-resolution CT of the chest is within normal limits. Which of the following is the most appropriate next step in management?

Asthma is an episodic, chronic respiratory disorder characterized by airway obstruction caused by inflammation and hyperresponsiveness of the bronchial smooth muscle.

Asthma is reversible, which means the obstruction can virtually disappear with medications like bronchodilators, and inducible, which means the obstruction can occur in response to a variety of stimuli; including allergens, irritants, and respiratory tract infections.

Clinical manifestations are highly variable, ranging from infrequent and mild symptoms that have minimal functional limitations, to frequent acute asthma exacerbations causing significant impairment in functional capacity, and even life-threatening respiratory failure that’s often referred to as status asthmaticus.Now, if you suspect asthma, you should first perform an ABCDE assessment to determine whether your patient is stable or unstable.

Unstable patient0:55–3:14

If they’re unstable, stabilize their airway, breathing and circulation, obtain IV access, and begin continuous vital sign monitoring including heart rate and blood pressure.

Next, obtain focused history and physical, order labs, including ABG, and perform spirometry to assess the patient’s peak expiratory flow, or PEF, for short.

Finally, don’t forget to place your patient on pulse oximetry. History typically reveals shortness of breath, cough, and chest tightness.

On the flip side, physical exam is likely to show tachypnea and use of accessory inspiratory muscles. In addition, auscultation can reveal bilateral wheezing due to inflamed and narrowed airways, and if the condition worsens, you may find decreased or even absent breath sounds, since less air is reaching alveoli.

Next ABG might reveal arterial pH of 7.35 or less and pCO2 above 45 mmHg, indicating respiratory acidosis and hypercapnia; while spirometry usually shows PEF less than 40%.

Finally, pulse oximetry might demonstrate saturation below 90%.If this is the case, suspect acute asthma exacerbation, or even status asthmaticus, and immediately administer supplemental oxygen at 100% FiO2, inhaled bronchodilators including a short-acting muscarinic antagonist like ipratropium and a short-acting beta agonist or SABA like albuterol, as well as systemic corticosteroids, either oral or IV.

If the patient doesn’t respond to treatment, you can also give a single dose of IV magnesium. Lastly, in severe cases, you may even proceed with endotracheal intubation and mechanical ventilation, especially if your patient has altered mental status, cyanosis, or inability to maintain respiratory effort, as well as worsening hypercapnia and respiratory acidosis.

Stable patient3:14–4:07

Now let's go back to the ABCDE assessment and discuss stable patients. First, perform a focused history and physical.

Your patient is likely to report shortness of breath, coughing, and chest tightness, often triggered by allergens and exercise, and they may even have an existing diagnosis of asthma.

On the other hand, physical examination often reveals tachypnea and wheezing. If this is the case, suspect asthma, or if your patient has already been diagnosed with asthma, suspect worsening of its severity.

You’ll want to monitor the patient's vital signs, including heart rate, blood pressure, respirations, and oxygen saturation.

Finally, provide supplemental oxygen to maintain an oxygen saturation above 90%. The next step in patient management is to obtain spirometry, including FVC and FEV1 to confirm the diagnosis.

Spirometry4:07–6:32

FVC, or forced vital capacity, is the maximum amount of air a person can forcibly exhale from their lungs after a maximum inhalation, while FEV1 is the volume of air exhaled during the first second of this forced exhalation.

Now, here’s a clinical pearl to keep in mind! Spirometry can be performed with a simple handheld spirometer.

First, have your patient take a maximal breath in, then forcibly exhale into the spirometer until all of the air is emptied from their lungs.

This will generate a flow-volume loop, which will differentiate between obstructive and restrictive patterns of lung disease.

Now that you’ve completed spirometry, calculate the patient’s FEV1 to FVC ratio. If the ratio is within normal range, or even elevated, for the patient’s age, consider an alternative diagnosis.

On the other hand, if the ratio is below normal range, suspect an obstructive lung disease, which includes asthma. But this is not enough to confirm the diagnosis so your next step is to perform bronchodilator reversibility, or BDR testing.

BDR testing consists of giving an inhaled dose of a SABA, followed by repeat spirometry, paying particular attention to the FEV1.

If BDR testing reveals an improvement in FEV1 of 12% or more after SABA administration, you can make a confident diagnosis of asthma.

On the other hand, if BDR testing reveals an improvement in FEV1 of less than 12% after SABA administration, then it’s not considered significant.

Still, to confidently rule out asthma, you’ll need to perform further investigations, such as fractional exhaled nitric oxide testing, bronchial provocation testing, exercise challenge testing, or demonstration of peak expiratory flow variability on serial testing over the course of two weeks.

If no reversibility of airway obstruction is evident on additional testing, consider an alternative diagnosis. However, if reversibility is present, then you can confidently diagnose asthma.

Now, once you make the diagnosis of asthma, the next step is to assess symptom severity, which will help define the intensity of treatment.

Assess symptom severity6:32–7:15

Based on asthma manifestations over the previous month, asthma symptoms can be classified as well controlled, partly controlled, or poorly controlled.

To determine the type, ask the following questions. First, ask your patient if they have been having daytime asthma symptoms more than twice per week.

Next, determine if asthma symptoms have awakened them at night. Also, ask if they have been using a SABA inhaler to relieve asthma symptoms more than twice per week.

Finally, ask your patient whether or not their asthma symptoms are persistent and limit their activities. Now, determine the intensity of treatment by the number of yes and no responses your patient gives to these questions.

Well-controlled asthma7:15–7:58

To start off, well controlled asthma is when the answer to all of these questions is NO. Patients with well controlled asthma can be started on step 1 or step 2 therapies.

Step 1 therapy is a low-dose inhaled corticosteroid, or ICS, and a long-acting beta agonist, or LABA, used in a combination inhaler known as an ICS/LABA as a reliever on an as needed basis only.

Step 2 therapy is an ICS used on a daily basis, as a controller medication. No matter which option is chosen, a SABA is also commonly prescribed as a reliever medication medication.

On the other hand, if your patient answers yes to 1 or 2 of these questions, their asthma is partly controlled. In this case, start your patient on step 3 therapy, which consists of a low-dose ICS/LABA daily as a controller medication; with a SABA commonly prescribed as a reliever medication.

Partly-controlled asthma7:58–8:17

Finally, if your patient answers yes to 3 or 4 of these questions, their asthma is poorly controlled, so you should start them on step 4 or step 5 therapies.

Poorly-controlled asthma8:17–9:37

Step 4 therapy is a medium-dose ICS/LABA used on a daily basis as a controller medication, whereas step 5 therapy includes a high-dose ICS/LABA used on a daily basis as a controller medication.

In severe cases, consider adding a long acting muscarinic antagonist, or LAMA, or even biologic therapy. No matter which option is chosen, a SABA is also commonly prescribed as a reliever medication.Now here’s a clinical pearl to keep in mind!

Asthma is a variable disease, meaning it can be triggered by many environmental variables, and complicated by other risk factors and disease processes.

These include smoking, exposure to smoke or other respiratory irritants, comorbidities such as allergic rhinitis and obesity, and prior asthma exacerbations in the past year.

Sometimes, asthma may even decompensate or even improve over time in the absence of an identifiable trigger. For these reasons, you should reassess your patient periodically both clinically and by repeating spirometry.Okay, as a quick recap… If you suspect asthma, first, you should determine whether or not your patient is stable or unstable.

If they are unstable, suspect asthma exacerbation, and immediately start your patient on supplemental oxygen; inhaled SAMA like ipratropium and SABA like albuterol; and systemic corticosteroids.

Review9:37–11:45

Unresponsive cases may get IV magnesium, while severe cases might require endotracheal intubation and mechanical ventilation.

On the other hand, if your patient is stable, obtain spirometry and calculate the patient’s FEV1 to FVC ratio. If the ratio is within the normal range or elevated, consider an alternative diagnosis.

On the other hand, if the ratio is below the normal range, suspect an obstructive respiratory condition, and proceed with BDR testing.

FEV1 improvement of less than 12% requires further investigations. If additional testing reveals no reversibility of airway obstruction, consider an alternative diagnosis.

However, if reversibility is present, then you can confidently diagnose asthma. On the other hand, if BDR testing reveals FEV1 improvement of 12% or more, you can also make a confident diagnosis of asthma.

Either way, your next step is to assess the patient’s symptom severity and determine the type of asthma. Individuals with well-controlled asthma should be started on step 1 or step 2 therapies.

Step 1 therapy includes ICS/LABA on an as-needed basis only; while step 2 is an ICS used on a daily basis. On the other hand, patients with partly controlled asthma require step 3 therapy, which consists of a low-dose ICS/LABA daily.

Finally, individuals with poorly controlled asthma should be started on step 4 therapy, which includes medium-dose ICS/LABA; or step 5 therapy, which includes high-dose ICS/LABA.

In severe cases, consider adding a LAMA, or even biologic therapy. Finally, no matter which step is chosen, a SABA could be also prescribed as a reliever medication.

includes high dose IC laba in severe cases consider adding a Lama or even biologic therapy Finally no matter which step is chosen a saba could