Coughing is a normal reflex necessary to clear secretions and prevent infections. It is initiated by what is known as “irritant receptors” located in the surface of the bronchi of the lungs.
What follows is a rapid sequence of responses, including air gushing into the lungs. The glottis and the vocal cords close, trapping that air at high pressures. Then the abdominal and expiratory muscles contract, and with the glottis and vocal cords now open air is expelled at a rate as high as 100 miles per hour. That produces the cough.
It is a relatively violent event when you consider the stress that a cough causes to tissue. For this reason, these irritant receptors are adaptable and don’t react repeatedly to the same stimulus. Ideally, it is supposed to be a one-time event that clears out the irritating element.
Just as there are consequences to having a weak cough -- it leaves one vulnerable to pneumonia and other infections since it is often ineffective in clearing secretions, raising the risk of infection -- there are also consequences to coughing in excess, or having a chronic cough.** The most common causes of excessive cough include:**
Asthma from hyper-reactive airways
Gastro esophageal reflux, since acid reflux into the surface of the esophagus will stimulate the same nerve that stimulates the lungs and causes the cough
Infection, which usually instigates the first treatment approach to a persistent cough (antibiotics)
Another newer but common occurrence is an ongoing cough resulting from the side effects of medications, specifically the very popular blood pressure medications called ACE inhibitors.
When all of these conditions are addressed and treated, and the cough still persists for more than two months, the condition is identified as chronic cough. The American College of Chest Physicians published a consensus statement on the approach to this entity.
This condition can be quite disturbing to an individual, since coughing can be traumatic to delicate tissues like the vocal cords and the voice box. Medications that suppress the cough reflex (cough suppressants) are often used as a last resort, but they do have many undesirable side effects. In addition, some medications have a narcotic component that can be addictive.
A new way to look at treating chronic coughA new approach to chronic cough that has been shown to be effective, without undesirable side effects, is an intervention by speech language and pathology professionals called ** resonant therapy** -- a therapy, usually lasting between four and six sessions, that's familiar to many professionals who depend on their voices, such as performers and singers.
The process starts with evaluation and elimination of behaviors that may be habitual and perpetuating, such as excessive coughing and throat clearing. An education component emphasizing the futility of repeated coughing and the benefits of its suppression is part of resonant therapy. Therapists may offer an individual the following advice: “Just because you feel that there is something there/in your throat doesn’t mean that it has to be expelled.”
Over time the therapy will help to build the capacity of the individual to voluntarily suppress the cough.
Resonant therapy also involves voice exercises designed to gain better control of the voice and diminish trauma. Awareness of the different frontal consonants that are created toward the front of the mouth and with the lips, such as the letters m, n, and d and consonants that originate from the back of the throat (letters g and _h) _has also been found to help. The therapist will often practice one-syllable words with the patient and try to help them to control the effort during enunciation, or have them repeat single-syllable words using different voice pitches.Ultimately, resonant therapy trains the arytenoid muscles, located next to the vocal cords, to open and close, helping to strengthen the muscles. (Their lack of coordination can result in the shaky voice often heard in older individuals.)
One well-known technique, the Lee Silverman Voice Treatment, has been studied in the treatment of voice disorders in people with Parkinson’s disease.
Resolving a chronic cough through these self-awareness techniques can significantly improve a patient's sense of well-being and quality of life. And as chronic coughing can also be bothersome to family, friends or co-workers, a resolution will also be beneficial to them.
Eli Hendel, M.D. is a board-certified Internist and pulmonary specialist with board certification in Sleep Medicine. He is an Assistant Clinical Professor of Medicine at Keck-University of Southern California School of Medicine, Qualified Medical Examiner for the State of California Department of Industrial Relations, and Director of Intensive Care Services at Glendale Memorial Hospital. His areas of expertise in private practice include asthma, COPD, sleep disorders, obstructive sleep apnea, and occupational lung diseases.