Computers Tuned In to Dangerous Sleep Disorder

An ancient myth told of the plight of Undine, a nymph condemned to a life of sleeplessness out of fear that she would stop breathing while asleep and die. Modern science calls it sleep apnea.

The ailment--a cessation of breathing during sleep--is also known as as “Undine’s curse,” and it afflicts a large number of middle-age, overweight men, many of whom unknowingly suffer the condition.

“Snoring is the most common symptom of sleep apnea, which is characterized by lapses between breaths for as long as 20 to 40 seconds a time during sleep, several hundred times a night,” said Donald Johns, director of the Sleep Disorders Clinic at the San Gabriel Valley Medical Center.

“Sleep apnea goes all the way back to Greek mythology,” Johns said. “We’re finally getting the upper hand on it by diagnosing those who didn’t even know they were affected.”

The condition now is being diagnosed with the help of a computer and electrodes that monitor patients at home while they sleep.

The monitoring system was designed by medical and computer specialists at the Stanford University Sleep Disorders Clinic in Palo Alto, a center that long has been a world leader in the study of sleep disorders, Johns said.

The computer, in use at several medical centers around the country, is among the most accurate of devices capable of monitoring the sometimes life-threatening disorder, Johns explained.

“Actually, the system is somewhat like a halter monitor,” Johns said of the mesh halter to which electrodes are affixed and stuck on the chests of patients to measure a series of vital functions, including the length of time between breaths.

The halter and electrodes are placed on the patient at the clinic and worn home. At night while the patient sleeps the electrodes are plugged into a small box that records the patient’s sleep patterns.

“The system measures heart rate, lung function, oxygen saturation in the blood and paradoxing, which is the opposite movements of chest and abdomen,” he said.

Johns said the monitoring box is brought back to the clinic the next morning, at which time the data collected during the night is fed into and analyzed by a computer.

“If the patient is apneic,” he said, “the computer might show decreased respiration during sleep, a decrease in heart rate and a desaturation of oxygen in the bloodstream.

“There are different kinds of sleep apnea, but most often we’ll see patients with an occlusion of the upper airway.”

Sleep apnea also has been diagnosed in infants, who can be aroused from lapses in breathing by being shaken, an action that doctors say awakens the baby and forces the brain to message the lungs to begin functioning again.

Sleep apnea in the case of infants is the cause of sudden infant death syndrome, for which there is no cure.

Johns described the typical sleep apnea patient as over 40, considerably overweight, a victim of frequent headaches and given to loud snoring at night and constant sleepiness during the day.

“If the apneic patient is tremendously obese, weight loss is the first recommendation that we make. But a tracheostomy is the gold standard for people who stop breathing for one to two minutes at a time,” he said.

Dr. Glenn Weisman, chief of surgery at the medical center, said people being treated for sleep apnea also are cautioned to avoid medications and alcohol before bedtime.

But he added that when weight loss and limited alcohol consumption do not cure the condition, surgery may be in order.

“It’s a simple surgical procedure called uvulopalatopharyngoplasty, or UPPP,” Weisman said.”

The operation is similar to a tonsillectomy and involves removal of tissue at the back of the throat, which enlarges air passages to enable unobstructed breathing, Weisman explained.

“Other surgical methods also successfully treat sleep apnea caused by nasal deformity or nasal polyps,” he said.

The computerized diagnostic method also helps determine if the patient suffers from other types of sleeping and breathing disorders, primarily central nervous system dysfunction in which “the brain is not telling the lungs and diaphragm to move,” Johns said.