Cheng Kunming, Li Wanqing, Lu Yanqiu, Wu Haiyang, Zhou Jianxin
Department of Intensive Care Unit, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Department of Operating Room, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, China.
Heliyon. 2023 Aug 12;9(8):e19119. doi: 10.1016/j.heliyon.2023.e19119. eCollection 2023 Aug.
The aim of this study was to assess the effect of modified high-flow oxygen therapy on end-expiratory lung volume (EELV) and positive end-expiratory pressure (PEEP) in tracheotomized patients with normal pulmonary, acute hypoxic respiratory failure (AHRF) or chronic obstructive pulmonary disease (COPD).
A ventilator and an artificial lung model were used to simulate the normal or strong inspiratory effort state of normal lung, AHRF and COPD patients. The traditional high-flow respiratory humidification therapy device connected with a standard interface (group A), and the modified therapy device added two types of resistance valves (group B, inner diameter 7.7 mm, length 24.0 mm; group C, inner diameter 7.7 mm, length 34.0 mm) to the exhalation end of the standard interface. The changes of end-expiratory lung volume (ΔEELV) and PEEP with the increase of flow rate (10 L/min, 20 L/min, 30 L/min, 40 L/min, 50 L/min, 60 L/min) in the three groups was recorded.
Under simulated conditions of normal lung, AHRF and COPD, as the flow rate increased by using the modified therapy device, the PEEP values in all groups showed an exponential increasing trend, and the ΔEELV also increased accordingly. In addition, under the same flow rate level, the PEEP values of the two modified high-flow oxygen therapies (Group B and Group C) were significantly higher than those of the standard high-flow oxygen therapy (Group A) ( < 0.05). In the normal lung model with normal or strong inspiratory effort, and in the AHRF or COPD model with strong inspiratory effort, when the flow rate was higher than 30 L/min, the PEEP levels of Group B were significantly lower than those of Group C ( < 0.05). In the AHRF model with normal inspiratory effort, when the flow rate was between 10 L/min and 60 L/min, the PEEP levels of Group B were significantly lower than those of Group C ( < 0.05). Moreover, in the COPD model with normal inspiratory effort, the PEEP levels of Group B were significantly lower than that of Group C only when the flow rate was 60 L/min ( < 0.05).
The addition of different types of resistance valves to the high-flow exhalation end may be a feasible solution to improve the clinical efficacy of tracheotomized high-flow oxygen therapy.
本研究旨在评估改良高流量氧疗对气管切开的肺部正常、急性低氧性呼吸衰竭（AHRF）或慢性阻塞性肺疾病（COPD）患者呼气末肺容积（EELV）和呼气末正压（PEEP）的影响。
使用呼吸机和人工肺模型模拟正常肺、AHRF和COPD患者的正常或强力吸气状态。传统高流量呼吸湿化治疗装置连接标准接口（A组），改良治疗装置在标准接口呼气端增加两种阻力阀（B组，内径7.7mm，长度24.0mm；C组，内径7.7mm，长度34.0mm）。记录三组随着流速（10L/min、20L/min、30L/min、40L/min、50L/min、60L/min）增加时呼气末肺容积（ΔEELV）和PEEP值的变化。
在正常肺、AHRF和COPD的模拟条件下，使用改良治疗装置随着流速增加，各组PEEP值呈指数上升趋势，ΔEELV也相应增加。此外，在相同流速水平下，两种改良高流量氧疗（B组和C组）的PEEP值显著高于标准高流量氧疗（A组）（<0.05）。在正常或强力吸气的正常肺模型中，以及在强力吸气的AHRF或COPD模型中，当流速高于30L/min时，B组的PEEP水平显著低于C组（<0.05）。在正常吸气的AHRF模型中，当流速在10L/min至60L/min之间时，B组的PEEP水平显著低于C组（<0.05）。此外，在正常吸气的COPD模型中，仅当流速为60L/min时，B组的PEEP水平显著低于C组（<0.05）。
在高流量呼气端增加不同类型阻力阀可能是提高气管切开高流量氧疗临床疗效的可行解决方案。
