Experiencing shortness of breath during exercise can be extremely distressing, particularly when it occurs in a child, teen or young adult. Asthma is a very common cause of this symptom, but when asthma medications do not completely relieve or prevent the shortness of breath, a different problem might be present. Exercise-Induced Laryngeal Obstruction (EILO) is a transient, reversible narrowing of the larynx that occurs during exercise. In addition to shortness of breath, patients with EILO can also experience chest tightness, chest pain and inspiratory stridor. Some will also hyperventilate and even experience panic reactions. Symptoms related to EILO are the worst at the peak of exercise intensity and then quickly resolve when exercise ceases. EILO can affect the performance of even the most elite athletes. EILO is most commonly seen in adolescents and young adults, but also can be a problem for older children.
In my practice at TriStar Medical Group Children's Specialists, we commonly see pediatric patients who have problems with breathing during exercise. The diagnostic evaluation of EILO is one part of a general evaluation looking at the causes of exertional dyspnea. As part of this evaluation in children, we consider both very common and very rare diagnoses as well as potentially dangerous conditions. We evaluate for EILO and other conditions by performing a "combined exercise test" that attempts to re-produce the exercise induced symptoms while simultaneously examining the heart, lungs and airway in real time.
Because ELIO resolves very quickly after peak exercise, the larynx must be examined during exercise. To accomplish this, we perform Continuous Laryngoscopy during Exercise (CLE). During the exam, a thin, flexible fiber optic laryngoscope is introduced prior to exercise and remains in place throughout an exercise challenge designed to reproduce the symptoms. A local numbing agent makes the scope comfortable and tolerable during exercise, even for our youngest patients. The scope provides real-time viewing of the voice box during the exercise test.
The Children's Hospital at TriStar Centennial is one of only a handful of sites nationwide where this type of testing is routinely performed in pediatric patients. There currently is no off-shelf way to perform CLE and each testing center has to create their own mechanism for holding the scope during the exam. Many early descriptions of ELIO (then called vocal cord dysfunction) highlighted involvement of the vocal folds. However, we now know that EILO can also be caused by collapse arytenoid cartilages and other structures causing a narrowing of the laryngeal airway.
Real-time evaluation of the problem helps providers more precisely determine the best treatment option. The first line of treatment of ELIO focuses on relaxing or opening the vocal folds. Our speech language pathologists teach patients specific exercises designed to open the larynx and keep it open during exertion. The exercises are simple and patients usually can be trained to control their larynx in as few as two or three visits. Additional treatment can involve inhaled anticholinergic medications and, in rare instances, surgery.
It is important that patients seek help to treat limiting respiratory symptoms, especially if those symptoms do not respond to the first line of treatment.