| 摘要 |
The method and device trigger ventilatory support to assist the patient's respiration. Myoelectrical activity of a patient's respiratory-related muscle is sensed to detect respiratory effort, and to produce a myoelectrical signal representative of the sensed muscle myoelectrical activity. Respiratory flow and pressure can also be measured to produce respective respiratory pressure and respiratory flow signals. A logic trigger circuit triggers ventilatory support in relation to the myoelectrical signal, respiratory flow signal and/or respiratory pressure signal to assist respiration of the patient. The amplitude of the myoelectrical signal is compared to a given threshold, and ventilatory support is triggered when the amplitude of the myoelectrical signal is higher than this threshold. Increment of myoelectrical signal amplitude can also be detected to trigger ventilatory support, while decrement of the myoelectrical signal amplitude can be detected to request nontriggering of the ventilatory support. Advantageously, two myoelectrical signal components of opposite polarities are generated in response to sensing of the myoelectrical activity on the two opposite sides of the center of a depolarizing region of the respiratory-related muscle, respectively. The two myoelectrical signal components are subtracted and added to produce subtraction and addition signals, respectively, the addition signal is multiplied by a constant to produce a multiplied signal, the multiplied signal is compared to the subtraction signal, and the subtraction signal is accepted as myoelectrical signal when the subtraction signal has an amplitude higher than the multiplied signal.
|
