Yaroshetskiy Andrey I, Krasnoshchekova Anna P, Tkachenko Fedor D, Rubashchenko Alina V, Zubarev Daniil D, Konanykhin Vasiliy D, Savelenok Maxim I, Nosenko Maxim M, Merzhoeva Zamira M, Avdeev Sergey N
Pulmonology Department, Sechenov First Moscow State Medical University (Sechenov University), 8/2, Trubetskaya Str, Moscow, 119991, Russia.
BMC Anesthesiol. 2025 Aug 23;25(1):416. doi: 10.1186/s12871-025-03267-9.
High-flow nasal cannula is widespread in patients with hypoxemic and hypercapnic respiratory failure, but physiological data concerning influence of the combination of breathing pattern, preset flow rate (PFR), and inspiratory oxygen fraction (FO) on end-expiratory pressure (EEP), capnogram, oxygram, and exhaled tidal volume (VTe) remains insufficient.
The study included 20 healthy subjects with 12 combinations of PFR (30-60-80 L/min) and FO (40-60-80-100%) multiplied by 4 breathing patterns: mouth closed (CM), mouth open (OM), and combination of the CM and OM with hyperpnea (HCM and HOM). Pressure, capnogram, oxygram were measured from hypopharyngeal catheter, VTe, and subject's comfort were assessed.
Inspiratory oxygen fraction (FiO) were close to FO at the PFR of 30 L/min (CM), and 60 L/min (HCM). FiO during the OM and HOM were much less than FO, variable and unpredictable. PFR of 60 L/min was sufficient to keep FiO close to FO during the CM and HCM. End-expiratory carbon dioxide (FCO) decreased with an increase in the PFR and FO, reaching 1.4 (1.1-1.7)% at FO 100% and PFR of 80 L/min. EEP had grown a lot with the PFR increase and were highly variable reaching 11.1 (7.7-14.8) cmHO at the PFR of 80 L/min. VTe at the PFR of 60 and 80 L/min were 948.0 (715.0-1204.8) and 948.0 (869.0-1422.0) ml, respectively. PFR of 60 L/min and 80 L/min were associated with discomfort.
HCM, OM, and HOM in healthy subjects decreased FiO and FCO (more pronounced during OM and HOM). HFNC within the CM and HCM provided flow-dependent CPAP-effects over a wide range and could be associated with lung hyperinflation. An excessive PFR led to discomfort.
ClinicalTrials.gov identifier: NCT06189716 , registered on 19/12/2023.
高流量鼻导管在低氧血症和高碳酸血症呼吸衰竭患者中广泛应用，但关于呼吸模式、预设流速（PFR）和吸入氧分数（FO）的组合对呼气末压力（EEP）、二氧化碳波形图、氧合图和呼出潮气量（VTe）影响的生理数据仍然不足。
该研究纳入了20名健康受试者，采用PFR（30 - 60 - 80 L/分钟）和FO（40 - 60 - 80 - 100%）的12种组合，并乘以4种呼吸模式：闭嘴（CM）、张嘴（OM）以及CM和OM与深呼吸（HCM和HOM）的组合。通过下咽导管测量压力、二氧化碳波形图、氧合图，评估VTe和受试者的舒适度。
在PFR为30 L/分钟（CM）和60 L/分钟（HCM）时，吸入氧分数（FiO）接近FO。OM和HOM期间的FiO远低于FO，且变化不定、难以预测。60 L/分钟的PFR足以在CM和HCM期间使FiO接近FO。呼气末二氧化碳（FCO）随着PFR和FO的增加而降低，在FO为100%且PFR为80 L/分钟时降至1.4（1.1 - 1.7）%。EEP随着PFR的增加而显著升高，变化很大，在PFR为80 L/分钟时达到11.1（7.7 - 14.8）cmH₂O。60 L/分钟和80 L/分钟的PFR时VTe分别为948.0（715.0 - 1204.8）和948.0（869.0 - 1422.0）ml。60 L/分钟和80 L/分钟的PFR与不适相关。
健康受试者中的HCM、OM和HOM降低了FiO和FCO（在OM和HOM期间更明显）。CM和HCM中的高流量鼻导管在广泛范围内提供了流量依赖性持续气道正压通气（CPAP）效应，可能与肺过度充气有关。过高的PFR会导致不适。
ClinicalTrials.gov标识符：NCT06189716，于2023年12月19日注册。
