Vocal Cord Dysfunction (VCD)/Functional Breathing Disorders

Vocal Cord Dysfunction (VCD) is a broad and non-specific term, but it is widely used to describe a functional breathing disorder in which the vocal folds come together during inhalation, thus narrowing the airway and making it difficult to inhale. Although other terms may be more correct or descriptive, we will refer to this general category of disorders as VCD, because so many of our patients come to us with a diagnosis of VCD.

VCD is commonly seen in young athletes who develop symptoms during athletic exertion. These athletes may be incorrectly diagnosed with exercise-induced asthma.

The disorder is also common in adults. Symptoms often cause awakening in the middle of the night, but they may occur at any time. These symptoms may be triggered by eating or drinking, especially something sour or very sweet.

Symptoms

Some of the common symptoms of VCD are:

• Sudden inability to inhale
• A sensation of shortness of breath, choking, strangling
• Sensation of tightness in the chest or throat
• Gasping sound when inhaling
• The noise on inhalation is called stridor; it’s the sound that results when the vocal folds are vibrating during INHALATION. This is different from wheezing, which is a tight, breathy sound on EXHALATION that is a hallmark characteristic of asthma.

Cause

When symptoms occur during the night, the cause is nearly always related to reflux. In this case, juices from the stomach reflux back up the esophagus and spill over onto the larynx, irritating the vocal folds and surrounding laryngeal mucosa. The irritation can cause the vocal folds to twinge or spasm (hence called laryngospasm), in much the same way that the eye will shut forcefully if irritated by a sudden foreign object or substance. This feels like a choking sensation, or like the airway is suddenly shut off. When the individual attempts to inhale forcefully, the vocal folds are actually sucked together, preventing inhalation. This causes more forceful attempts at inhalation and creates a vicious cycle that can be very frightening to the individual. The vicious cycle is such that the vocal folds may relax slightly during exhalation, but come together during inhalation. Thus, the disorder is often called Paradoxical Vocal Fold Motion because of this backwards movement of the vocal folds. The gasping sound on inhalation is known as inhalatory stridor.

The scenario is similar for an athlete. The individual begins panting and gasping for air, trying to inhale more forcefully, and the vocal folds are sucked together. The same frightening cycle ensues. It may also happen when the athlete chokes slightly on his or her own saliva, especially when the throat becomes very dry from panting. Another possibility is that the athlete does not use his or her diaphragm and rib cage muscles optimally for inhalation, and therefore tries too hard to inhale, again creating the sucking together of the vocal folds.

In some cases, an individual with VCD is able to gain control of his or her own breathing, and the episode ends. In other cases, he or she needs to be seen in an emergency room. In either case, the experience can be so alarming that if the conditions present themselves again, the same set of responses is triggered by the anxiety. Moreover, it is generally not helpful to suggest to an individual who cannot breathe that they should "just relax."

Treatment

Treatment for reflux is an important component of treating some cases of VCD, especially in adults. This usually involves prescribing anti-reflux medications to reduce the irritation. Also, you may be counseled about dietary precautions to alleviate reflux. Relief may occur in days, or may take a month more.

At the Lions Voice Clinic, we provide breathing training so you know how to reverse the paradoxical motion of the vocal folds and breathe easily again. Most often, the breathing training includes flexible endoscopy. This enables you to observe the motion of the vocal folds while doing the various maneuvers learned in training. Watching yourself control your own breathing is generally very reassuring, and even if the laryngospasms continue for a time, the full-blown episodes usually end within a few weeks.

In the case of an athlete, particularly a young athlete, care is taken to differentiate between a pulmonary (lung) problem such as asthma, and VCD, or a functional breathing disorder. Often, we use a treadmill to simulate athletic exertion, and then, an endoscopic exam is done immediately to confirm the occurrence of abnormal vocal fold behaviors during exertion. Interestingly, we see many athletes with breathing problems who do not actually demonstrate true paradoxical motion of the vocal folds. Often, the arytenoid cartilages rock forward during the forced inhalation. Even though this does not occlude the airway, it diverts the air and causes a sensation of inability to inhale. It is also quite common that the airway remains completely open, but air is not moving adequately to support the level of exertion, because the diaphragm is not contracting fully enough to fill the lungs adequately. If the abdominal musculature is held too tightly, the diaphragm cannot descend for inhalation. In all these cases, breathing training is done as previously described, and may include work on the treadmill to train special breathing techniques for athletic exertion. Because of the anxiety associated with this disorder, the young athlete and his or her parents are counseled carefully and sensitively.