Pulmonary

Carrie A. Jaworski

INTRODUCTION

Patients with pulmonary disorders can benefit greatly from exercise when their disease process is under proper control.
Awareness of when and when not to participate and the ability to use pharmacologic agents and environmental controls greatly enhance one’s ability to participate safely.

ASTHMA

Asthma is a chronic pulmonary disorder characterized by varying degrees of airflow obstruction, bronchial hyperresponsiveness, and underlying chronic inflammation (42).
Approximately, 22 million adults and 6 million children in the United States have chronic asthma (42).
The National Heart, Lung, and Blood Institute (NHL-BI) has set forth guidelines on the diagnosis and management of asthma in an effort known as the National Asthma Education and Prevention Program (NAEPP). This program is evidence based and routinely updates its recommendations based on the newest research. The third edition was completed in 2007; the latest recommendations can be found at the NHLBI Web site: http://www.nhlbi.nih.gov/ (21).
While in the past, asthmatics were discouraged from exercise, today it is recognized that regular exercise can reduce airway reactivity and decrease medication use (8). Current data support this trend, with decreased numbers of asthmatics reporting limitations in their activity (5,42).

Diagnosis of Asthma

History or presence of episodic symptoms of airflow obstruction, such as wheezing, chest tightness, shortness of breath, or cough. Absence of symptoms at time of examination does not exclude diagnosis.
Airflow obstruction needs to be at least partially reversible demonstrated through the use of spirometry. First, establish airflow obstruction: forced expiratory volume in 1 second (FEV₁) < 80% predicted and FEV₁/forced vital capacity (FVC) ratio < 70% or below the lower limit of normal. Then establish reversibility by an FEV₁ increase of ≥ 12% from baseline or ≥ 10% of predicted FEV₁ after using a short-acting inhaled β₂-agonist (41).
Must exclude other diagnoses, such as vocal cord dysfunction, vascular rings, and reflux disease, if spirometry is normal.
Classification of asthma severity is based on history and spirometry (Table 38.1).
Management should focus on patient education, environmental control, and objective monitoring.
Patient education: Patients and their families should understand signs and symptoms of an asthma exacerbation, the chronicity of the disease, and potential triggers of an attack. A written plan should be reviewed, and instruction on proper use of inhaled medications and peak flow monitoring should be provided.
Environmental control: Avoidance of exposure to precipitating factors is paramount. Potential triggers include pollen, mold, ozone, exercise, and cold air. Athletes should exercise indoors on bad weather days or use measures, such as masks, to decrease chance of attack. Indoor swimming is considered an excellent option secondary to the warm, moist environment at the pool. Some asthmatics are susceptible to aspirin and nonsteroidal anti-inflammatory drugs, so judicious use must be exercised (33).
Monitoring: Athletes need to be monitoring their peak flows on a daily basis to recognize decline in function, as well as response to treatment. Formal spirometry is recommended for initial diagnosis, after treatment and peak flows have stabilized, and then every 1-2 years when asthma is stable, or more often when unstable (42).
Pharmacologic therapy should be instituted to control inflammation and treat episodes of bronchoconstriction. Use a stepwise approach to treatment as outlined in Table 38.2.

Medication Classes

The two main classes of asthma medications are long-term control medications that are used to treat and control the persistent symptoms of asthma and short-acting agents that provide quick relief of symptom exacerbations.

Table 38.1 Severity Classification

			Classification of Asthma Control (Youth ≥12 years of age and adults)
	Components of Control		Well Controlled	Not Well Controlled	Very Poorly Controlled
Impairment	Symptoms		≤ 2 days a week	> 2 days a week	Throughout the day
	Nighttime awakening		≤ 2 × a month	1-3 × a week	≥ 4 × a week
	Interference with normal activity		None	Some limitation	Extremely limited
	Short-acting β₂-agonist use for symptom control (not prevention of EIB)		≤ 2 days a week	> 2 days a week	Several times per day
	FEV₁ or peak flow		> 80% predicted/personal best	60%-80% predicted/personal best	< 60% predicted/personal best
	Validated questionnaires
		ATAQ	0	1-2	3-4
		ACQ	≤ 0.75*	≥ 1.5	N/A
		ACT	≥ 20	16-19	≤ 15
Risk	Exacerbations		0-1 a year	≥ 2 a year (see note)
			Consider severity and interval since last exacerbation
	Progressive loss of lung function		Evaluation requires long-term follow-up care
	Treatment-related adverse effects		Medication side effects can vary in intensity from none to very troublesome and worrisome. The level of intensity does not correlate to specific levels of control but should be considered in the overall assessment of risk.
* ACQ values of 0.76-1.4 are indeterminate regarding well-controlled asthma.
ACQ, Asthma Control Questionnaire; ACT, Asthma Control Test; ATAQ, Asthma Therapy Assessment Questionnaire; EIB, exercise-induced bronchospasm; FEV₁, forced expiratory volume in 1 second.

LONG-TERM CONTROLLERS

Corticosteroids: Mechanism is to block late-phase reaction to allergens, decrease airway hyperresponsiveness, and inhibit inflammatory cell actions. Inhaled corticosteroids (ICSs) are the mainstay of treatment in the long-term control of asthma. ICSs are considered to be the most potent and consistently effective anti-inflammatory asthma medication (10,25,37,42,44). ICSs must be taken on a regular basis; therefore, they are not useful as a rescue medication. Side effects can include local irritation, dysphonia, and oral candidiasis. Systemic forms may be needed in asthma flares and cases recalcitrant to inhaled glucocorticoids.
Khellin derivatives: Cromolyn sodium (Intal) and nedocromil sodium (Tilade) act to stabilize mast cells, thus preventing the release of inflammatory mediators. Both are inhaled medications with a strong safety profile and can be considered as an alternative to ICSs but not a preferred therapy. Cromolyn is approved for children of all ages, while nedocromil is approved in children older than age 6. Both take about 2 weeks to demonstrate a therapeutic response.
Leukotriene modifiers: Zileuton (Zyflo), a 5-lipo oxygenase inhibitor, blocks the synthesis of leukotrienes, whereas zafirlukast (Accolate) and montelukast (Singulair), leukotriene receptor antagonists (LTRAs), block the effects of leukotrienes after they are formed. All 3 medications decrease airway inflammation and offer another alternative to ICSs. Montelukast and zafirlukast are approved in children, have a favorable safety profile, and are taken orally every day or twice a day. Less desirable is zileuton, which is not approved in children < 12 years old and requires dosing 4 times a day and monitoring of hepatic function.
Long-acting β₂-agonists (LABAs) are bronchodilators that last up to 12 hours after 1 dose. Examples include salmeterol and formoterol. LABAs are the recommended medication to be used in combination with ICSs for management of moderate to severe asthma (3,4,43). Concern regarding the use of LABA as monotherapy and an increased risk of asthma exacerbations and asthma-related deaths has caused a black box warning to be placed on all preparations containing a LABA (16,22). An expert panel recommends weighing the benefit of LABA use in uncontrolled asthmatics versus the small increased risk (42).

Immune modulators: Omalizumab is a monoclonal antibody that prevents binding of immunoglobulin (Ig) E to mast cells and basophils. It can be used as adjunctive therapy in patients older than 12 years with allergies and severe
asthma. It is for those with severe persistent asthma not controlled with a combination of high-dose ICS and LABA (14).

Table 38.2 Treatment: Stepwise Approach