《nmtyage》课件.pptVIP

If one is punched in the stomach, the abdominal muscles will contract as a protective reflex. The same happens in abdominal surgery during the skin incision or handling of the gut. To prevent this the muscles may need to be paralyzed with muscle relaxants during surgery. Critically ill patients are sometimes paralyzed to improve the ventilation, to decrease the work of breathing, or to decrease the metabolic rate and oxygen consumption. Whenever neuromuscular blockers are used, it is recommended to monitor their effect. There are two kinds of movement: Voluntary and involuntary. Involuntary movement is usually caused by painful stimulus. The painful stimulus creates sensory impulses. The spinal cord converts them to motor impulses which produce movement. The function of the neuromuscular junction can be divided into the following phases: 1) The arrival of a nerve action potential at the nerve terminal 2) Synthesis of Acetylcholine 3) Depolarization of the postjunctional membrane. In this process acetylcholine is a chemical transmitter between nerve and muscle. It binds to receptor on the muscle side and produces depolarization and muscle contraction. Nondepolarizing agents attach themselves to ACh receptors of the endplate, here they competitively bind and prevent released ACh from causing sufficient depolarization (EPP) to trigger off a muscle action potential and thus produce a longer lasting paralysis. Depolarizing agents rapidly block the effect of ACh by occupying the receptor sites for a short period (used for intubation). Due to depolarization, side effects may occur. * / GE Title or job number / * 神经肌肉传导监测NMT GE Healthcare 朴松哲 2006-09-16 Neuromuscular Transmission (NMT) Monitoring E-NMT NMT 监测方式 测量肌肉对刺激的收缩反应 最常用尺神经 刺激 测量反应 NMT 监 测 刺激模式： TOF，DBS，ST，PTC ST 单次刺激 TOF 四个成串刺激 (临床最常用） PTC 强直刺激后计数 （监测深度神经阻滞） DBS 双强直刺激 刺激强度和时间可调 刺激反应在屏幕上独立显示 文字提示肌松状态 应用肌松药前 TOF%＝100 ；TOF值＝4 用药初期 TOF％ 下降，肌松药起效 TOF值降到2或2以下时，即可进行插管。 外科手术通