Method and apparatus to detect and monitor the frequency of obstructive sleep apnea
The present invention provides a method and apparatus for detecting and monitoring obstructive sleep apnea. The apparatus includes an intracardiac impedance sensor to measure intracardiac impedance, a movement sensor to measure an amount of movement of a patient, and a controller operatively coupled to said intracardiac impedance sensor and said movement sensor, said controller adapted to receive at least one of an intracardiac impedance and the amount of movement of the patient and detect obstructive sleep apnea based upon said intracardiac impedance and said movement.
1. A method of detecting and monitoring obstructive sleep apnea, comprising:
measuring an intracardiac impedance to detect a change in the intracardiac impedance corresponding to a change in cardiac filling;
measuring an amount of movement of a patient; and
determining the presence of obstructive sleep apnea based upon the change in the intracardiac impedance and the movement of the patient.
2. A method of claim 1 , wherein measuring the intracardiac impedance further comprises measuring the intracardiac impedance between an intracardiac atrial electrode and an intracardiac ventricular electrode.
3. A method of claim 1 , wherein measuring the intracardiac impedance further comprises detecting a decrease in the intracardiac impedance.
4. The method of claim 3 further comprising measuring an intrathoracic impedance to detect a change in intrathoracic impedance, and
determining the presence of obstructive sleep apnea based upon the change in the intracardiac impedance, the movement of the patient and the intrathoracic impedance.
5. The method of claim 4 further comprising estimating a minute ventilation using the intrathoracic impedance,
wherein determining the presence of obstructive sleep apnea further comprises detecting a rapid increase in the estimated minute ventilation followed by a slower decrease in the estimated minute ventilation.
6. A method of claim 1 , wherein measuring the amount of movement of the patient further comprises detecting a low amount of movement of the patient.
7. A medical device for detecting and monitoring obstructive sleep apnea, comprising:
means for measuring an intracardiac impedance to detect a change in the intracardiac impedance corresponding to a change in cardiac filling;
means for measuring an amount of movement of a patient; and
means for determining the presence of obstructive sleep apnea based upon the change in the intracardiac impedance and the movement of the patient.