Stephens Krista, Mitchell Nathan, Overton Sean, Tonna Joseph E
Department of Emergency Medicine, University of New Mexico, Albuquerque, NM 87131, USA.
Division of Emergency Medicine, Department of Surgery, University of Utah Health, Salt Lake City, UT 84132, USA.
J Clin Med. 2021 Mar 2;10(5):1001. doi: 10.3390/jcm10051001.
The transition from control modes to spontaneous modes is ubiquitous for mechanically ventilated patients yet there is little data describing the changes and patterns that occur to breathing during this transition for patients on ECMO. We identified high fidelity data among a diverse cohort of 419 mechanically ventilated patients on ECMO. We examined every ventilator change, describing the differences in >30,000 sets of original ventilator observations, focused around the time of transition from control modes to spontaneous modes. We performed multivariate regression with mixed effects, clustered by patient, to examine changes in ventilator characteristics within patients, including a subset among patients with low compliance (<30 milliliters (mL)/centimeters water (cmHO)). We found that during the transition to spontaneous modes among patients with low compliance, patients exhibited greater tidal volumes (471 mL (364,585) vs. 425 mL (320,527); < 0.0001), higher respiratory rate (23 breaths per minute (bpm) (18,28) vs. 18 bpm (14,23); = 0.003), greater mechanical power (elastic component) (0.08 mL/(cmHO × minute) (0.05,0.12) vs. 0.05 mL/(cmHO × minute) (0.02,0.09); < 0.0001) (range 0 to 1.4), and lower positive end expiratory pressure (PEEP) (6 cmHO (5,8) vs. 10 cmHO (8,11); < 0.0001). For patients on control modes, the combination of increased tidal volume and increased respiratory rate was temporally associated with significantly low partial pressure of arterial oxygen (PaO)/fraction of inspired oxygen (FiO) ratio ( < 0.0001). These changes in ventilator parameters warrant prospective study, as they may be associated with worsened lung injury.
对于接受机械通气的患者而言，从控制模式转换为自主模式的情况普遍存在，但关于接受体外膜肺氧合（ECMO）治疗的患者在这一转换过程中呼吸所发生的变化及模式，相关数据却很少。我们在419名接受ECMO治疗的机械通气患者组成的多样化队列中识别出了高保真数据。我们检查了每一次通气机设置的变化，描述了超过30000组原始通气机观察数据中的差异，重点关注从控制模式转换为自主模式的时间点。我们进行了混合效应的多变量回归分析，并按患者进行聚类，以研究患者体内通气机特征的变化，其中包括低顺应性（<30毫升（mL）/厘米水柱（cmH₂O））患者的一个子集。我们发现，在低顺应性患者向自主模式转换的过程中，患者表现出更大的潮气量（471毫升（364,585）对425毫升（320,527）；P<0.0001）、更高的呼吸频率（每分钟23次呼吸（bpm）（18,28）对18 bpm（14,23）；P = 0.003）、更大的机械功率（弹性成分）（0.08毫升/（厘米水柱×分钟）（0.05,0.12）对0.05毫升/（厘米水柱×分钟）（0.02,0.09）；P<0.0001）（范围0至1.4）以及更低的呼气末正压（PEEP）（6厘米水柱（5,8）对10厘米水柱（8,11）；P<0.0001）。对于处于控制模式的患者，潮气量增加和呼吸频率增加的组合在时间上与动脉血氧分压（PaO₂）/吸入氧分数（FiO₂）比值显著降低相关（P<0.0001）。通气机参数的这些变化值得进行前瞻性研究，因为它们可能与肺损伤加重有关。
