波形分析

机械通气,压力波形的产生,呼吸运动方程,压力时间曲线,压力型 vs 容量型,压力型保证气道压力在一定范围内，避免气压伤病情稳定时，潮气量相对稳定潮气量大小和压力高低、胸肺顺应性、气道阻力、自主呼吸能力有关，有时波动较大,容量型保证有效通气量，避免容积伤通过调整吸气流速、吸气波形、吸呼比等，可将压力控制在适当范围胸肺顺应性、气道阻力以及人机对抗时吸气压力增高，可能引起气压伤,正常波形,呼吸力学监测,R: RESISTANCE 阻力呼吸力学三要素：压力（P）流速（F）容积（V）,P,V,R,阻 力 RESISTANCE,肺通气的阻力有两种：弹性阻力:包括肺的弹性阻力和胸廓的弹性阻力，是平静呼吸时的主要阻力，又称静态阻力，约占总阻力的70，克服肺组织和胸廓阻力。其大小可以用顺应性来衡量。非弹性阻力:包括气道阻力、粘性阻力和惯性阻力，又称动态阻力，约占总阻力的30，其中以气道阻力为主。,肺的弹性阻力用肺顺应性表示，肺顺应性是用单位压力的变化能引起多少容积的改变来表示. C=V / P非弹性阻力用气道阻力表示，气道阻力是单位时间容积（流速）改变引起的压力变化值。 R= P / L,Pel,Pr,定容模式下的气道阻力增加,定压模式下的气道阻力增加,定容模式下的顺应性降低,定压模式下的顺应性降低,通气策略,容量控制IPPVSIMVIMVA/C,压力控制PCV,自主呼吸ASB/PSCPAP,呼吸空间,自主呼吸,机械通气,两者应该有效的相结合,自主呼吸和机械通气不能有效的配合,人机对抗咳嗽可中断通气,病人不能吸气或呼气,病人能吸气，但不能呼气。压力增加。,镇静剂.病人自主呼吸受抑制,IPPV,PCV,在应用镇静剂数周后,在结束使用镇静剂后数小时及在自主呼吸开始出现后,塌陷 /实变,自主呼吸下的肺泡复张,83-10c,自主呼吸方式,由于肺的复张而减少分流的发生更好的静脉回流减少呼吸肌萎缩的发生加强了脱机,TRIGGERING(实现同步),Under ideal conditions the patient expends minimum effort to trigger the ventilator and the initiation of gas flow is nearly instantaneous (e.g., short time delay between initiation and gas flow delivery). Older ventilators often demonstrated a 400 ms time delay and a Paw of 6 cmH2O between triggering and flow delivery.Modern ventilators improved triggering by both a reduced time delay ( 100 ms) and Paw ( 2 cmH2O).,压力触发,压力触发,呼吸机的触发功能,流量触发,流量触发,呼吸机的触发功能,PSV,Ineffective Triggering无效触发,Ineffective triggering occurs when the patient makes a respiratory effort that is not sensed by the ventilator, resulting in no assistance (volume or pressure) being delivered.,Ineffective triggering occurs when the patient makes a respiratory effort that is not sensed by the ventilator, resulting in no assistance (volume or pressure) being delivered. Ineffective efforts represented wasted metabolic work and may lead to patient discomfort.,One consequence of these ineffective efforts is an underestimation of the patients respiratory frequency.The ventilators digital display of respiratory frequency only accounts for triggered breaths.,Autotriggering自动触发,Autotriggering occurs when the conditions for triggering are met in the absence of patient effort.Causes of autotriggering Leaks in the circuit pressure/flow transients related to movement of water in the circuit,肺气肿患者的气道塌陷与肺泡回缩力降低,常见异常波形,呼吸回路泄漏的波形,呼吸管道内有液体的波形,吸气时间（TI）变化在压控通气波形上的变化,动态肺过度充气（Dynamic pulmonar