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According to the International Association of Logopedics and Phoniatrics (2015), the overall
prevalence of dysphagia is 13.5%. Although dysphagia can appear at any age, it occurs much
more often among the el derly, particularly in nursing home patients. Young children with birth
defects, pervasive developmental disorders, and neuromuscular disorders are also at higher risk
for dysphagia. Incidence figures for dysphagia also depend on the researcher’s definition of the
disorder. Some define dysphagia narrowly as the inability to move a liquid or food substance
from the mouth to the stomach. In this definition, only the motor acts of sucking, chewing, and
swallowing are included. Other researchers define dysphagia broadly, including the sensory,
perceptual, and cognitive awareness of the patient and his or her ability to fulfill hydration and
nutritional needs orally.
Issues related to the management of dysphagia by medical facilities, physicians, nurses,
occupational therapists, dietitians, and speech- language pathologists are common in medical
malpractice cases (Tanner, 2009; Tanner & Culbertson, 2014). In this book, a broad definition of
dysphagia is used to accommodate the complexity of the disorder. Broad definitions are often used
for forensic purposes and during litigation:
Dysphagia: Impairment of the emotional, cognitive, sensory, and/or motor acts involved
with transferring a substance from the mouth to stomach, resulting in failure to maintain
hydration and nutrition, and posing a risk of choking and aspiration. (Tanner, 2003b, p. 70)In this definition of dysphagia, the patient’s awareness and cognitive abilities are addressed
relative to eating and swallowing. The patient’s sensory abilities, including responses to food
odors, are also considered, as well as the motor acts of moving food and liquid from the mouth to
the stomach.
Relationship Between Speech and Swallowing
There is a fundamental relationship between speech production and deglutition (Culbertson
& Tanner, 2012). Humans are omnivorous and can suck, bite, tear, chew, and swallow many types
of food. Over thousands of years, they have developed the structures, neurology, and musculature
to ingest a variety of meats, fruits, nuts, vegetables, and liquids of differing viscosity to sustain
life. Human teeth can tear and grind. The lips close and seal the oral cavity to create the negative
intraoral air pressure necessary for sucking. The tongue is capable of assuming the many shapes
and movements necessary to move food and liquid to the posterior oral cavity in preparation for
swallowing. The vocal cords ref lexively close and protect the air passageway to the lungs during the
swallow. The anatomical structures, neurology, and musculature necessary for these actions have
evolved to permit the complex acts of sucking, chewing, and swallowing. Speech has also evolved
as an overlaid function to deglutition; the same muscles and structures used for swallowing also
are used to produce speech sounds. For example, the teeth are used for dental phonemes, the lips
for plosives, and the vocal cords to produce voiced speech sounds.
Normal Swallowing
Swallowing consists of three interconnected phases: oral, pharyngeal, and laryngeal- esophageal.
During eating, swallowing can occur as often as 300 times per hour (Zemlin, 1998). The oral phase,
sometimes called the buccal phase, has two stages: oral preparation and transportation. During the
preparation stage, food is masticated (chewed) and liquid is contained. The lips, cheeks, and jaw
muscles are impor tant in mastication. In oral preparation, a bolus is created by rolling the food
into a ball and saturating it with liquid from the meal and saliva. During the transportation stage,
the tongue moves the liquid and bolus to the back of the oral cavity in preparation for swallowing.
During the pharyngeal phase of swallowing, the velum elevates, closing off the passageway
to the nasal cavity. The vocal cords close to prevent the liquid and food particles from entering