Dysphagia & Patients with Tracheostomy and Mechanical Ventilation

What is a tracheostomy?

A tracheotomy is a procedure where an opening is created in the neck and into the airway (trachea) and a tracheostomy is the resulting stoma (hole) that is created.  A tracheostomy tube is typically placed into the stoma to allow for direct access to the trachea for breathing and removing secretions from the airway and lungs.  The tube enables air to flow directly through the trachea rather than through the nose and mouth, bypassing the upper airway.

Tracheostomy and Aspiration:

Patients with tracheostomy and mechanical ventilation are at a heightened risk of aspiration with reports of up to 87% of patients who are provided with oral intake aspirating (Elpern et al, 1994), with the majority of those silently aspirating. Silent aspiration is when food, liquid, or secretions go into the airway and there are no overt signs such as coughing or throat clearing. This is concerning, as aspiration can result in pneumonia, especially in an already vulnerable population.  Despite the high rate of aspiration, many individuals with tracheostomy and mechanical ventilation can safely take some oral intake following a proper assessment by a trained speech-language pathologist, which can reduce delays in beginning oral intake and reduce complications from unsafe oral feedings.  

When a tracheotomy is initially performed, typically a cuffed tracheostomy tube is placed.  The reason for a cuffed tracheostomy is to provide a seal, closing off the upper airway to effectively deliver positive pressure ventilation.  Although some individuals can be effectively ventilated with a cuffless or deflated cuffed tracheostomy tube, many will initially require an inflated cuff.  There is a common misconception that the cuff of the tracheostomy tube prevents aspiration.  However, the definition of aspiration is when material (secretions, food, liquids, reflux) passes below the level of the vocal folds, which is the last line of defense in protecting the airway.  Once material reaches the cuff of the tracheostomy tube, it has already been aspirated.  Aspirated material can colonize with bacteria at the site of the cuff and eventually pass around the cuff and into the lower airways and lungs.  At most, the cuff can delay material from reaching the lungs. Studies have shown that there are higher rates of aspiration, silent aspiration and respiratory infections when the cuff is inflated compared to deflated (Davis et al, 2002, Ding, R. & Logemann, J. 2005, Hernandez et al, 2013).

How does a tracheostomy affect swallowing?

In the population with tracheostomy and mechanical ventilation, dysphagia is often multi-factorial.

The underlying medical diagnosis, acuity of the patient, and the reason for the initial tracheostomy tube are important considerations.  Tracheotomy may be performed on individuals with neuromuscular diseases such as stroke, ALS, Guillian Barre, MS, Parkinson’s Disease, and muscular dystrophy.  Obstructive airway disease, head and neck cancer/surgery and adult respiratory distress syndrome may also result in the need for tracheotomy.  Dysphagia can result from the impact of these medical conditions. 

Another factor that may increase the risk for aspiration is that most individuals with tracheostomy are initially orally intubated with an endotracheal tube. This is a tube that goes in the mouth through the larynx and into the trachea.  Swallow studies within 24 hours of the oral intubation tube being removed have shown high rates of aspiration, with a high proportion being silent aspiration.  The endotracheal tube passes through the vocal folds, which can damage the folds, particularly during emergent intubation, multiple intubations, and extubation.  This places the individual at higher risk of aspiration since the vocal folds are largely responsible for airway protection.

Finally, there are reports of some specific effects of the presence of a tracheostomy on swallowing, particularly when the cuff is inflated.  This includes:

• Impaired laryngeal elevation (Ding & Logemann, 2005; Amethieu et al, 2012; Jung, S. et al, 2012; Logemann et al, 1998).
• Reduced subglottic air pressure (Gross et al, 1994; Gross et al, 2003)
• Desensitization of the larynx (Ding & Logemann, 2005; Amethieu et al, 2012; Seidl et al, 2005).
• Reduced effectiveness of the cough reflex
• Disruption of the vocal fold function (Sasaki CT et al, 1977; Shaker, R et al, 1995).

For further information of the specific studies, please see Tracheostomy Education.

Swallow Assessment:

Because of the high aspiration and silent aspiration rate, a thorough assessment by a dysphagia specialist, usually a speech-language pathologist, is indicated.  There are some distinct considerations in assessing those with tracheostomy and mechanical ventilation:

• Duration of intubation and number of intubations/extubations.
• When, how and why the tracheostomy tube was placed
• Tracheostomy tube size, manufacturer and cuff type
• If the patient is currently on mechanical ventilation, ventilator settings and weaning status
• Other pertinent information includes medical diagnosis, respiratory function, medications, prior level of swallow function and current means of nutrition.  A cognitive assessment and oral mechanism are completed. 
• Assessing laryngeal function is important in determining if swallowing is safe.  If the cuff is inflated, the person cannot produce voice in order to indicate if vocal fold function is intact.  Also, cough strength and vocal changes after providing oral intake are pieces of information to help assess if the food or liquid is safely swallowed. 

In order to assess laryngeal function, the cuff (if present) must be deflated following a physician order.  Cuff deflation allows some air to escape through the upper airway, although airflow will continue to flow out of the tracheostomy tube.  Once the cuff has been completely deflated, a speaking valve may be placed after assessing for upper airway patency.  There are various types of speaking valves. The Passy-Muir Valve is the only biased closed position valve and can be used for patients with tracheostomy who are spontaneously breathing or in-line with mechanical ventilation.  Once a speaking valve is placed it restores the patient to more normal physiology as all exhaled air is redirected through the upper airway.  A bedside swallow assessment may continue as if it is a normal airway.  Benefits of utilizing a biased closed position valve during a swallow evaluation include:

• Ability to assess for change in vocal quality, cough strength and the patient’s response to oral intake 
• Improved cough reflex to clear any material that enters the airway, including secretions
• Improved sensation
• Improved secretion management
• Aspiration has been reduced or eliminated in some patients (Suiter, D et al, 2003; Stachler, R et al, 1996; Dettelbach et al 1995; Elpern et al, 1994, 2000; Gross et al, 1994, 2003)
• Restoration of subglottic air pressure (Gross et al, 2003) and maintaining lung volumes to perform maneuvers such as supraglottic and supersupraglottic
• Ability to perform expiratory muscle strength retraining

Occlusion of the tracheostomy tube by digital occlusion or capping also provides the above benefits.

Due to the high rates of aspiration and silent aspiration, instrumental assessments are strongly recommended.  The modified barium swallow study (MBSS) or a flexible endoscopic evaluation of swallowing (FEES) are the gold standards.  If use of the speaking valve is time limited, the SLP may assess different conditions such as having the cuff inflated, deflated and valve/cap on to determine the safest strategies for feeding. 

There are significant advantages to FEES in the tracheostomy and mechanically ventilated population including:

• secretions are able to be assessed in a population where it may be unsafe to provide foods and liquids
• No barium or radiation
•  FEES is not time dependent and can assess patient fatigue over a meal
• No transportation as it can be completed at the bedside
• Potentially lower costs and less time spent than MBSS

In conclusion, patients with tracheostomy and mechanical ventilation are at a heightened risk for dysphagia and aspiration. Proper swallowing assessments can help determine swallow safety in order to advance to a diet. Modified barium swallow studies or flexible endoscopic evaluation of swallowing is strongly recommended in this population.

Nicole DePalma, MS, CCC-SLP, received her BA at Georgetown University and subsequently earned her MS at NY Medical College in Speech-Language Pathology.  She is the owner of Tracheostomy Education, an all inclusive resource for tracheostomy education and supplies.  As a member of the Passy-Muir team, she has presented courses on dysphagia and communication management at conferences and universities throughout the nation.   

Flexible Endoscopic Evaluation of Swallowing (FEES) is available through Nicole DePalma at NDoscopy Dysphagia Specialists.  NDoscopy proudly partners with hospitals, subacute and skilled nursing facilities in New York City to provide mobile FEES and consulting for establishing interdisciplinary tracheostomy teams.  Ndoscopy also services patients in a private practice office, located at 3250 Westchester Ave Suite 204, Bronx NY 10457.  

Other mobile FEES providers in the US may be found through this map: https://maphub.net/FlatlandTherapy/mobile-fees-providers-04-30-2019

Resources:

Amathieu, R. et al. (2012). Influence of the cuff pressure on the swallowing reflex in tracheostomized intensive care unit patients. British Journal of Anaesthesia. Oct;109(4):578-83.

Davis, et al. (2002) Swallowing with a Tracheotomy Tube in Place: Does Cuff Inflation Matter? Journal of Intensive Care Medicine.17(3): 132-135.

Dettelbach, M., et al. (1995). Effect of the Passy Muir^® Valve on Aspiration in Patients with Tracheostomy. Head & Neck, 297-300.

Ding, R. & Logeman, J. (2005). Swallow Physiology in Patients with Trach Cuff Inflated or Deflated: A Retrospective Study. Head & Neck. Sep;27(9):809-13

Gross, R. D., Dettelbach, M. A., Eibling, D. E., & Zajac, D. (1994). Measurement of subglottic air pressure during swallowing in a patient with tracheostomy. Otolaryngology-Head and Neck Surgery, 111(2), 133.

Gross, R. D., Mahlmann, J., & Grayhack, J. P. (2003). Physiologic effects of open and closed tracheostomy tubes on the pharyngeal swallow. Annals of Otology, Rhinology and Laryngology, 112(2), 143-152.

Shaker, R, Milbrath, M, Junlong, R, Campbell B, Toohill, R, Hogan, W. (1995). Deglutitive aspiration in patients with tracheostomy: Effect of tracheostomy on the duration of vocal cord closure. Gastrointerology 108(5), 1357-1360. 

Seidl RO, Nusser-Müller-Busch R, Ernst A. The influence of tracheotomy tubes on the swallowing frequency in neurogenic dysphagia. Otolaryngol Head Neck Surg. 2005 Mar; 132(3):484-6.

Stachler, R. J., Hamlet, S. L., Choi, J. and Fleming, S. (1996), Scintigraphic Quantification of Aspiration Reduction With the Passy‐Muir Valve. The Laryngoscope, 106: 231-234. doi:10.1097/00005537-199602000-00024

Suiter, D, McCullough, G, Powell, P.  Cuff deflation and one way tracheostomy speaking valve placement on swallowing disorders, Dysphagia 18:284–292 (2003) DOI: 10.1007/s00455-003-0022-x