Xu X T, Sun Q, Xie J F, Pan C, Yang Y, Qiu H B, Liu L
Department of Critical Care Medicine, Zhongda Hospital, Southeast University, Nanjing 210009, China.
Zhonghua Nei Ke Za Zhi. 2019 Jan 1;58(1):43-48. doi: 10.3760/cma.j.issn.0578-1426.2019.01.008.
To compare the trigger delay and work of trigger between neurally adjusted ventilatory assist (NAVA) and pressure support ventilation (PSV) in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients with intrinsic positive end-expiratory pressure (PEEP) during mechanical ventilation. AECOPD patients with intrinsic PEEP (PEEPi) greater than or equal to 3 cmH(2)O (1 cmH(2)O=0.098 kPa) were enrolled during invasive mechanical ventilation. Subjects were ventilated with low, medium and high pressure under either NAVA or PSV mode. Servo Tracker software continuously recorded the waveform of ventilator and respiratory mechanics indexes (including respiratory frequency, inspiratory tidal volume (Vti), minute ventilation volume (VE), peak airway pressure (PIP), inspiratory time), and calculated trigger and expiratory conversion delay time, work of trigger and total work of breath. A total of 14 AECOPD patients were enrolled with the average PEEPi (4.3±1.3) cmH(2)O. PSV inspiratory trigger delay time was positively correlated with PEEPi (0.913, 0.05). Compared with PSV, NAVA significantly decreased trigger delay time in low, medium and high pressure level groups [(48±17) ms vs. (167±86) ms, (63±65) ms vs. (247±240) ms, (63±49) ms vs. (342±192) ms,respectively all 0.05]. Similar results were shown as to work of trigger [(0.92±0.36) μV∙s vs. (1.22±0.70) μV∙s, (1.08±0.51) μV∙s vs. (1.62±1.25) μV∙s, (1.20±0.96) μV∙s vs. (2.29±1.02) μV∙s, all 0.05]. Trigger delay time increased according to the increase of pressure level in PSV mode. The presence of PEEPi in AECOPD patients leads to obvious trigger delay under PSV mode, which is positively correlated with PEEPi level. NAVA significantly reduces trigger delay time and work of trigger compared with PSV mode.
比较神经调节通气辅助（NAVA）与压力支持通气（PSV）在机械通气期间慢性阻塞性肺疾病急性加重期（AECOPD）合并内源性呼气末正压（PEEP）患者中的触发延迟和触发功。纳入有创机械通气期间内源性PEEP（PEEPi）大于或等于3 cmH₂O（1 cmH₂O = 0.098 kPa）的AECOPD患者。受试者在NAVA或PSV模式下分别以低、中、高压进行通气。Servo Tracker软件持续记录呼吸机波形和呼吸力学指标（包括呼吸频率、吸气潮气量（Vti）、分钟通气量（VE）、气道峰压（PIP）、吸气时间），并计算触发和呼气转换延迟时间、触发功和总呼吸功。共纳入14例AECOPD患者，平均PEEPi为（4.3±1.3）cmH₂O。PSV吸气触发延迟时间与PEEPi呈正相关（0.913，P < 0.05）。与PSV相比，NAVA在低、中、高压水平组均显著降低触发延迟时间[分别为（48±17）ms对（167±86）ms、（63±65）ms对（247±240）ms、（63±49）ms对（342±192）ms，均P < 0.05]。触发功方面也有类似结果[（0.92±0.36）μV∙s对（1.22±0.70）μV∙s、（1.08±0.51）μV∙s对（1.62±1.25）μV∙s、（1.20±0.96）μV∙s对（2.29±1.02）μV∙s，均P < 0.05]。PSV模式下触发延迟时间随压力水平升高而增加。AECOPD患者中PEEPi的存在导致PSV模式下明显的触发延迟，且与PEEPi水平呈正相关。与PSV模式相比，NAVA显著降低触发延迟时间和触发功。
