Stages of Swallowing
Safe and effective swallowing is dependent upon perfect timing of three basic stages, as well as the effective performance by many nerves and muscles involved in the process. The three stages of swallowing include:
- Oral Phase
During the oral phase, food is chewed and mixed with saliva to form a soft consistency called a bolus. The tongue then moves the bolus toward the back of the mouth.
Patients with impairment of the oral stage may experience difficulty creating a seal around a fork or spoon with their lips, chewing solid consistencies, forming chewed food into a bolus or moving the bolus to the back of the mouth.
- Pharyngeal Phase
During the pharyngeal phase, the vocal folds close to keep food and liquids from entering the airway. The larynx rises inside the neck and the epiglottis moves to cover it, providing even more airway protection.
If the pharyngeal phase is impaired, food or liquid can move into the throat before the automatic swallow is triggered, resulting in food or liquid touching the vocal folds or penetrating the vocal folds and moving into the lungs.
Common symptoms include:
- Coughing before, during or shortly after swallowing
- A choking sensation
- Shortness of breath
- Changes in voice quality after swallowing
- Repeated pneumonia
- Weight loss
- Esophageal Stage
During the final stage, the esophageal stage, the bolus moves into the esophagus, the muscular tube that contracts to push the bolus into the stomach.
If the esophageal stage is affected, the patient might experience heartburn, vomiting, burping or abdominal pain.