Abstract: A method for treating obstructive sleep apnea in a patient by electrical stimulation of muscles of the upper airway includes detecting an obstructive apnea and then stimulating muscles of the upper airway in response to the apnea. The apnea is detected by monitoring changes in a respiratory effort waveform of the patient for a parameter characteristic of the patient's level of respiratory effort which is averaged over successive respiratory cycles to provide a baseline average. A limit value is then generated from the baseline average and the value for the parameter is compared with the limit value. If the limit value is exceeded, an apnea event is detected. Electrical stimulation can then be applied to a muscle of the upper airway upon detection of the apnea at a level which restores patency to the airway.

Abstract: A half-cuff electrode for mounting on a nerve comprising a hollow, semi-cylindrical body of nonconductive material having an open, U-shaped cross section with an interior base portion of the U-shaped cross section adapted to fit closely about a selected portion of the circumference of the nerve. The electrode may be secured in contact with the selected portion of the nerve by placing the nerve within the open, base portion of the body and applying to at least one leg of the U-shaped body a biasing force sufficient to retain the nerve within the body base portion. Since the electrode has a half-cuff design and the method used for securing it to the nerve leaves one side of the half-cuff open, the nerve is able to swell without compromising the circulation of nutrients through the nerve tissue.