Swallowing

What is swallowing?

Swallowing is the action of passing food or drink that has been broken down in the mouth into the pharynx, or throat, and subsequently into the esophagus, so that it may be pushed through the digestive tract.

How do we swallow?

A cartilaginous structure called the epiglottis closes over the entrance to the trachea (windpipe) ensuring that the swallowed bolus passes into the pharynx behind the trachea, so that the bolus does not enter the lungs. The normal swallow consists of the following phases

• Pre-Oral Preparatory Phase
  Includes looking at the food, salivating, using utensils, and putting it into the mouth and sensory recognition of food approaching the mouth.
• Oral preparatory phase
  In this stage, the food is chewed/masticated into smaller pieces and tasted. The food is manipulated (masticated if a solid) into a cohesive unit (referred to as a bolus) in preparation for the remaining phases of the swallow.
• Oral Transition/Transport phase
  When the bolus passes the anterior faucial pillars/touches the posterior wall of the pharynx, sensory receptors in the oropharynx and tongue are stimulated and pharyngeal swallow is triggered, the oral stage ends and the pharyngeal stage begins.
• Pharyngeal Phase of the Swallow
  A number of physiological activities occur almost simultaneously as a result of pharyngeal triggering (sensory receptors triggering the pharyngeal swallow). The velum is raised which prevents the entry of food into the nasopharynx. The tongue is retracted, preventing the food from re-entering the mouth. The epiglottis drops down over the top of the larynx, protecting the airway and the bolus passes down on both sides of the epiglottis. The esophageal phase begins as the bolus passes through the Upper Esophageal Sphincter (UES) entirely.
• Esophageal phase of swallow This phase is involuntary, the bolus is moved down the esophagus via peristaltic wave motion with some help from gravity. The bolus enters the stomach, the swallowing process has finished, and digestion begins.

What happens if swallowing goes wrong?

In healthy people, the presence of foreign material in the airway is extremely uncomfortable and will stimulate immediate gag and coughing reflexes. If the swallowing goes wrong, the food may become lodged in and would obstruct the trachea causing choking and coughing. The food that makes its way down the trachea into your lungs can lead to a very serious case of pneumonia.

What is dysphagia?

Dysphagia simply means a difficulty in swallowing. Difficulties in swallowing may cause the food to be easily aspirated into the lungs, potentially leading to bacterial infection and a form of pneumonia known as aspiration pneumonia. It can also prevent an individual from eating enough food for adequate nutrition and to maintain weight.

Red flag signs for dysphagia

• Recurrent pneumonia Weight loss - 5% or more of ideal weight over one month with no apparent etiology
• Coughing at or after meal times
• Facial grimacing Increased duration / time taken to eat
• Pocketing of food in the mouth
• Aspiration - silent or audible - signs- reddening of eyes, spiked fever, gurgly voice post meals Increased secretions in the mouth- copious, stringy
• Heartburn or indigestion
• Hiccups
• Dehydration
• Labored breathing

Testing Dysphagia and Swallowing therapy

1) Bedside assessment

Speech-language pathologists are trained to test swallowing. The first step is a bedside assessment.

• The speech-language pathologist will evaluate how well the muscles in the mouth move.
• The speech-language pathologist will ask questions to see if the patient can remember any techniques they might need to learn.
• The speech-language pathologist will listen to the patient’s voice for an idea of how the voicebox is working.

2) Fiberoptic endoscopic evaluation of swallowing (FEES)

Fiberoptic endoscopic evaluation of swallowing (FEES) is now a first choice method for studying swallowing disorders on account of the various advantages it offers: easy to use, very well tolerated, allows bedside examination and is economic. Videoendoscopic evaluation of swallowing is performed with a fiberoptic rhinopharyngoscope for studying the physiology and physiopathology of certain stages of swallowing, particularly the pharyngeal stage. This examination offers detailed information of swallowing and of the relative functions of the upper airways and upper digestive tract.

3) Modified Barium Swallow (MBS):

A radiological examination performed while the person swallows barium-coated substances, done to assess quality of the swallowing mechanisms of the mouth, pharynx, and esophagus.

This evaluation is followed by a treatment. Each treatment plan is unique and designed to meet specific needs.

Treatment plans generally include exercises to improve coordination of muscle movements in the mouth and throat

• A plan may also include techniques to help compensate for lost function.
• The speech-language pathologist may recommend that survivors change the food and liquids they eat and drink.

Various swallowing maneuvers are implemented along with diet and posture modification. Appropriate treatment of such disorders is provided by the highly trained professionals.

The treatment of any disorder requires a multidisciplinary and holistic approach and hence, here, swallowing therapy plays a vital role.