Detecting and treating swallowing problems could reduce risk
Most of us think of pneumonia as a complication of the flu. But it can also develop when food or saliva containing germs accidentally goes down the trachea (windpipe) and into the lungs, where it starts an infection. Called aspiration pneumonia, this condition typically occurs in elderly people who have difficulty swallowing (dysphagia).
Now research suggests that swallowing problems may be responsible for some of the increased pneumonia risk in people with chronic obstructive lung disease (COPD). The good news is that detecting swallowing problems and taking preventive steps can lower your chances of developing aspiration pneumonia.
Timing Is Everything
The issue: Both breathing and eating involve the mouth and pharynx (throat). When you breathe in air through your mouth or nose, it passes down the pharynx through the larynx (voice box) and into the trachea. While eating, food or saliva also passes from your mouth into the pharynx. But instead of going down the larynx and trachea, it is diverted to the esophagus, the tube that connects the pharynx with your stomach.
This diversion occurs as food or saliva moves into the pharynx, triggering the epiglottis (a flap of cartilage that covers the entrance to the larynx) to close and thus prevent food and saliva from entering the trachea and lungsa problem called aspiration.
Breathing is also involved in aspiration prevention. Healthy people exhibit an exhale-swallow-exhale pattern. And breathing stops momentarily during each swallow. This pattern produces sufficient air pressure to further prevent inhalation of food or saliva into the trachea and lungs. However, this coordination of breathing and swallowing is disrupted in people with COPD, according to a 2009 report in the American Journal of Respiratory and Critical Care Medicine, potentially increasing the risk of aspiration pneumonia.
In the study, researchers evaluated 25 middle-aged and older men with moderate to severe COPD and 25 men who were healthy. They tracked the participants' breathing and swallowing while they ate. In contrast to the normal swallowing pattern of the healthy men, those with COPD were more likely to swallow during an inhalation and, after a swallow, to resume breathing with another inhalation, increasing the risk of inadvertently inhaling food into the lungs.
In addition, when the men with COPD did swallow during an exhalation, it was more likely to occur at the end of a breath, when air pressure is lower and food is more likely to be aspirated into the lungs. The preference for inhalation during and after a swallow in people with COPD may occur because their need for air is so great that they inhale rather than exhale during and after a swallow. Muscle fatigue in the upper respiratory/digestive tract and anxiety also may play a role.
Getting a Diagnosis
If you suspect that you may have a swallowing problem, have previously had a bout of aspiration pneumonia, or have had more than one unexplained pneumonia, ask your doctor to refer you to a specialist (usually a speech-language pathologist) for an oral-pharyngeal swallow evaluation.
During this evaluation, the specialist will inspect your mouth and observe while you chew and swallow different foods. This assessment provides information about the strength of the muscles used to chew and swallow, how your mouth and tongue move, your voice quality after swallowing, and whether liquid or food remains in your mouth. Most experts also recommend one of the following tests:
- Videofluoroscopic swallow study (VFSS). For this test, you will be asked to eat and drink foods of various consistencies. The food is mixed with barium, which makes it easier to see on an x-ray. A radiologist will observe the passage of food from your mouth to your pharynx and esophagus on a video monitor and make a record of it. This test shows the mechanics of your swallowing and whether swallowed food enters the trachea. During the test, you may be asked to try various maneuvers to reduce your risk of aspiration.
- Fiberoptic endoscopic evaluation of swallowing (FEES). For this test, a thin, flexible fiberoptic tube (endoscope) with a tiny camera attached is placed through one of your nasal passages into the back of the throat. This enables the specialist to see the inside lining of the pharynx and larynx as well as what happens before, during, and after you swallow. Again, you may be asked to try several maneuvers to see if they help minimize aspiration.
- Fiberoptic endoscopic evaluation of swallowing with sensory testing (FEEST). This test is similar to FEES, except that small puffs of air are blown through the endoscope. The puff of air should cause the vocal cords in your larynx to involuntarily close. If it doesn't, you have impaired sensory function in your throat.
Prevention and Treatment
If a swallowing problem is diagnosed, the specialist will recommend a number of strategies to help reduce the risk of aspiration. These include dietary modifications, compensatory moves to use while eating, and good oral hygiene practices.