Difficulty Swallowing: All About Dysphagia

How do we swallow?

Swal­low­ing is a com­plex process. Some 50 pairs of mus­cles and many nerves work to move food from the mouth to the stom­ach. This hap­pens in three stages. First, the tongue moves the food around in the mouth for chew­ing. Chew­ing makes the food the right size to swal­low and helps mix the food with sali­va. Sali­va soft­ens and moist­ens the food to make swal­low­ing eas­i­er. Dur­ing this first stage, the tongue col­lects the pre­pared food or liq­uid, mak­ing it ready for swallowing.

The sec­ond stage begins when the tongue push­es the food or liq­uid to the back of the mouth, which trig­gers a swal­low­ing reflex that pass­es the food through the phar­ynx (the canal that con­nects the mouth with the esoph­a­gus). Dur­ing this stage, the lar­ynx (voice box) clos­es tight­ly and breath­ing stops to pre­vent food or liq­uid from enter­ing the lungs.

The third stage begins when food or liq­uid enters the esoph­a­gus, the canal that car­ries food and liq­uid to the stom­ach. This pas­sage through the esoph­a­gus usu­al­ly occurs in about 3 sec­onds, depend­ing on the tex­ture or con­sis­ten­cy of the food.

How does dys­pha­gia occur?

Dys­pha­gia occurs when there is a prob­lem with any part of the swal­low­ing process. Weak tongue or cheek mus­cles may make it hard to move food around in the mouth for chew­ing. Food pieces that are too large for swal­low­ing may enter the throat and block the pas­sage of air.

Oth­er prob­lems include not being able to start the swal­low­ing reflex (a stim­u­lus that allows food and liq­uids to move safe­ly through the phar­ynx) because of a stroke or oth­er ner­vous sys­tem dis­or­der. Peo­ple with these kinds of prob­lems are unable to begin the mus­cle move­ments that allow food to move from the mouth to the stom­ach. Anoth­er dif­fi­cul­ty can occur when weak throat mus­cles can­not move all of the food toward the stom­ach. Bits of food can fall or be pulled into the wind­pipe (tra­chea), which may result in lung infection.

What are some prob­lems caused by dysphagia?

Dys­pha­gia can be seri­ous. Some­one who can­not swal­low well may not be able to eat enough of the right foods to stay healthy or main­tain an ide­al weight.

Some­times, when foods or liq­uids enter the wind­pipe of a per­son who has dys­pha­gia, cough­ing or throat clear­ing can­not remove it. Food or liq­uid that stays in the wind­pipe may enter the lungs and cre­ate a chance for harm­ful bac­te­ria to grow. A seri­ous infec­tion (aspi­ra­tion pneu­mo­nia) can result.

Swal­low­ing dis­or­ders may also include the devel­op­ment of a pock­et out­side the esoph­a­gus caused by weak­ness in the esophageal wall. This abnor­mal pock­et traps some food being swal­lowed. While lying down or sleep­ing, a per­son with this prob­lem may draw undi­gest­ed food into the phar­ynx. The esoph­a­gus may be too nar­row, caus­ing food to stick. This food may pre­vent oth­er food or even liq­uids from enter­ing the stomach.

What caus­es dysphagia?

Dys­pha­gia has many caus­es. Any con­di­tion that weak­ens or dam­ages the mus­cles and nerves used for swal­low­ing may cause dys­pha­gia. For exam­ple, peo­ple with dis­eases of the ner­vous sys­tem, such as cere­bral pal­sy or Parkin­son’s dis­ease, often have prob­lems swal­low­ing. Addi­tion­al­ly, stroke or head injury may affect the coor­di­na­tion of the swal­low­ing mus­cles or lim­it sen­sa­tion in the mouth and throat. An infec­tion or irri­ta­tion can cause nar­row­ing of the esoph­a­gus. Peo­ple born with abnor­mal­i­ties of the swal­low­ing mech­a­nism may not be able to swal­low nor­mal­ly. Infants who are born with a hole in the roof of the mouth (cleft palate) are unable to suck prop­er­ly, which com­pli­cates nurs­ing and drink­ing from a reg­u­lar baby bottle.

In addi­tion, can­cer of the head, neck, or esoph­a­gus may cause swal­low­ing prob­lems. Some­times the treat­ment for these types of can­cers can cause dys­pha­gia. Injuries of the head, neck, and chest may also cre­ate swal­low­ing problems.

How is dys­pha­gia treated?

There are dif­fer­ent treat­ments for var­i­ous types of dys­pha­gia. First, doc­tors and speech-lan­guage pathol­o­gists who test for and treat swal­low­ing dis­or­ders use a vari­ety of tests that allow them to look at the parts of the swal­low­ing mech­a­nism. One test, called a fiber optic laryn­goscopy, allows the doc­tor to look down the throat with a light­ed tube. Oth­er tests, includ­ing video flu­o­roscopy, which takes video­tapes of a patient swal­low­ing, and ultra­sound, which pro­duces images of inter­nal body organs, can pain­less­ly take pic­tures of var­i­ous stages of swallowing.

Once the cause of the dys­pha­gia is found, surgery or med­ica­tion may help. If treat­ing the cause of the dys­pha­gia does not help, the doc­tor may have the patient see a speech-lan­guage pathol­o­gist who is trained in test­ing and treat­ing swal­low­ing dis­or­ders. The speech-lan­guage pathol­o­gist will test the per­son­’s abil­i­ty to eat and drink and may teach the per­son new ways to swallow.

Treat­ment may involve mus­cle exer­cis­es to strength­en weak facial mus­cles or to improve coor­di­na­tion. For oth­ers, treat­ment may involve learn­ing to eat in a spe­cial way. For exam­ple, some peo­ple may have to eat with their head turned to one side or look­ing straight ahead. Prepar­ing food in a cer­tain way or avoid­ing cer­tain foods may help oth­er peo­ple. For instance, those who can­not swal­low liq­uids may need to add spe­cial thick­en­ers to their drinks. Oth­er peo­ple may have to avoid hot or cold foods or drinks.

For some, how­ev­er, con­sum­ing foods and liq­uids by mouth may no longer be pos­si­ble. These indi­vid­u­als must use oth­er meth­ods to nour­ish their bod­ies. Usu­al­ly this involves a feed­ing sys­tem, such as a feed­ing tube, that bypass­es the part of the swal­low­ing mech­a­nism that is not work­ing normally.