The Link Between the Swallow Function and Aspiration Pneumonia
In order to determine the presence of a swallowing disorder, it is essential to understand the basic anatomy and physiology of a normal swallow function. This blog will describe the 4 phases of a normal adult swallow function and how undiagnosed symptoms could lead to serious complications, including aspiration pneumonia. *It is important to note the head and neck anatomy of an infant is different from an adult; therefore, the information below is not indicative of an infant’s swallow function.
The 4 main phases of a normal adult swallow functioun, include the oral preparatory phase, oral phase, pharyngeal phase, and esophageal phase.
Phase 1: Oral Preparatory Phase
The oral preparatory phase begins with an individual recognizing food or liquid followed by salivating. The individual then utilizes utensils and cups to place food or liquid into the oral cavity (mouth), completes a tight lip closure to prevent the food or liquid from spilling out of the mouth, and begins to masticate (chew) the food into little pieces.
When the food is sufficiently chewed, the tongue forms a bowl in order to maintain the food or liquid in a cohesive manner.
Phase 2: Oral Phase
The oral phase, also known as the anterior-posterior transit phase, means the tongue pushes the food or liquid from the front of the mouth to the back of the oral cavity. Once the food or liquid reaches the back of the tongue, the involuntary swallow is triggered. For larger bites, the tongue manages the food so only a portion of it will be initially swallowed.
The remaining portion of the food will be placed on the side of the mouth reserving it for subsequent swallows. This phase should last approximately 1 to 1.5 seconds.
Phase 3: Pharyngeal Phase
Due to the anatomy and physiology of the involuntary swallow, this phase is fairly complex in nature; therefore, it will be generally described for the purpose of educating non-medical individuals.
The pharyngeal phase begins when the food or liquid enters the pharynx (throat area). As it enters the pharynx, the following physiological activities simultaneously occur:
- The involuntary swallow takes place
- The larynx (a.k.a. voice box) closes
- The nasal passage closes
Once the involuntary swallow takes place, the food or liquid is directed to the esophagus and breathing is reinitiated.
Phase 4: Esophageal Phase
The esophageal phase begins when the food or liquid leaves the pharynx and enters into the esophagus. During this phase, the food or liquid must pass through a sequence of contractions initiated by the upper and lower esophageal sphincter muscles.
Due to gravity, these contractions occur in a top to bottom sequence. As the food or liquid reaches the lower esophageal sphincter muscle, the muscle relaxes. The food or liquid, then, flows into the stomach. The transit time for the esophageal phase is approximately 8-20 seconds.
Swallow Function and Aspiration Pneumonia
Aspiration occurs when an individual’s swallowing mechanism fails to work properly resulting in the inhalation of food, liquid, saliva, stomach acid, or vomit into the airway, below the vocal folds. Subsequently, it often results in aspiration pneumonia.
Aspiration pneumonia can occur at any age but is frequently diagnosed in children with a complex medical history and the elderly population. This diagnosis can result in longer hospital stays, morbidity, and mortality. It is a leading cause of death for individuals 85 years of age and older.
Common Signs of Swallowing Disorders
Coughing with food, liquids, and/or medication
Difficulty breathing when consuming food and liquid
Food and/or medications getting stuck in throat
GERD (esophageal reflux)
Change in vocal quality while consuming food, liquid, and/or medications
Malnutrition and/or unexplained weight loss
Runny nose or watery eyes while eating/drinking
Vomiting during or following the consumption of food, liquid, and/or medication
Spitting out food
E-Integrated SLP Services and Swallowing Disorders
E-Integrated SLP Services will first conduct a bedside swallow evaluation to determine if there is a potential swallowing disorder. If there are prevalant signs of a swallow disorder, the speech-language pathologist, if appropriate, may recommend a modified barium swallow study. This will determine exactly where the anatomical and physiological breakdown occurs, whether strategies decrease the risk of aspiration, and determine the safest diet.
We, then, initiate a client-centered plan of care.
As individuals, we typically take the anatomy and physiology of our bodies for granted; consequently, at times, we are not always aware of our swallowing issues.
At E-Integrated SLP Services, we understand swallowing disorders remain unsettling due to the “unknown” factor; however, we also understand the importance of prompt action regarding swallowing and “quality of life” concerns.
The following three attachments are a modified barium swallow study video, an x-ray taken at time of a modified barium swallow study, and a swallowing intervention chart. The video and chart are courtesy of Professional Imaging, LLC, who represent the largest provider of swallowing disorder consultations in the United States with over a decade of experience.
The x-ray below depicts a modified barium swallow study in 2014. A clinical fellow (CF) under my supervision spoke to me about a resident not consuming any food over the weekend. In addition, the nursing staff could not locate her partials.
Upon hearing these concerns from the CF, I made a recommendation to immediately contact the physician and Professional Imaging, LLC and request a modified barium swallow study. As the radiologist activated the x-ray machine, he discovered the resident swallowed her partials.
Please feel free to contact E-Integrated SLP Services for any questions or concerns regarding you or your loved one’s swallow function.