Therapy Techniques for Bilateral Abductor Palsy

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Answer

Typically, the intervention techniques for bilateral abductor vocal fold paralysis or palsy tends to be surgical in nature. Because abductor palsy is typically a result of damage to the recurrent laryngeal nerves, the presentation of symptoms is fairly homogeneous, presenting in two primary categories, respiratory and phonatory distress. Often it is the breathing symptoms that are the greater challenge medically, socially and within their employment settings. Damage to the recurrent laryngeal nerve is a typical complication of thyroid surgery, as your patient understands. However, this damage can be bilateral or unilateral and it would benefit you to know which they have as the phonatory and respiratory complications are worse with a bilateral case. In bilateral paralysis, severe respiratory and phonatory symptoms due to a limited glottal airway can result and a tracheostomy is usually performed in the early stages after thyroid surgery. Although the tracheostomy is a viable solution for short term airway patency, it is not an option for long-term maintenance of voice and breathing.

Surgical options include lateralization of the vocal folds to increase the width of the glottal airway, cordectomy and CO2 laser endoscopic arytenoidectomy. However, these surgical procedures are often complicated by the necessity to preserve vocal functioning and improve airway functioning. Other than the surgical management options, there is a relatively new non-invasive technique that was used with a single subject that had bilateral abductor vocal fold paralysis, called inspiratory threshold training (Baker, Sapienza, Davenport, Hoffman-Ruddy and Woodson, 2002). Because respiratory muscles are similar to other skeletal muscles, they can be strengthened with low-repetition, high force contractions. This type of training increases the strength of the muscle. The threshold training is completed using a inspiratory threshold training device that consists of a mouth piece attached to a cylinder and a one-way spring loaded valve. This product is now available through Aspire Products www.aspireproducts.org/ . The idea of the device is that inspiratory airflow is blocked by the valve until sufficient pressure is reached to overcome the spring force. The device is adjustable to the patient's appropriate training threshold, depending on their starting pressure point. The threshold pressure is usually set at 75% of the subjects maximum inspiratory pressure (MIP). Each of the patient's breaths should be about 3-4 seconds in duration, thus holding the valve open for that duration causing strength conditioning to occur. The Baker et. Al, 2002 study indicated that the threshold training after 5 weeks produced a 47% increase in MIP. The subject also reported decreases in dyspnea during speech and exercise tasks. Endoscopic views also demonstrated an increase in the glottal width as evidence of successful intervention using the threshold device.

Reference:

Baker, S.E., Sapienza, C. M., Davenport,, P., Hoffman-Ruddy, B., and Woodson, G., 2003. Inspiratory Pressure Threshold Training for Upper Airway Limitation: A Case of Bilateral Abductor Vocal Fold Paralysis. Journal of Voice, 17:3, pp. 384-394.

Bridget A. Russell is an Associate Professor at the State University of New York Fredonia and directs the Speech Production Laboratory in the Youngerman Centers for Communicative Disorders at the University. She has published in the Journal of Speech, Hearing and Language (JSHLR), Speech and Voice Review. She has presented over 70 peer reviewed presentations at national and international conferences on voice and respiratory disorders. Dr. Russell also has served as an editorial consultant for JSHLR, National Science Foundation (NSF) and DelMar Publishing Group. Dr. Russell's research interests include voice disorders in children and adults, professional voice, and respiratory disorders of speech production.