Timing of swallows in relation to respiratory phases is associated with aspiration events. Oxygen therapy possibly affects the timing of swallows, which may alter airway protective mechanisms. To compare the coordination between swallowing and respiration during water infusion in post-extubation patients using high flow nasal oxygen (HFNO) with the coordination in those using low flow nasal oxygen (LFNO). We conducted a randomized controlled crossover study in post-extubation patients. The patients extubated within 48 h were randomly assigned to two groups, namely, HFNO and LFNO. The eligible patients in each group received either HFNO with fraction of inspired oxygen (FiO2) 0.35, flow 50 L per minute (LPM), and temperature 34 °C or LFNO 5 LPM for 5 min. The coordination between swallowing and respiration was observed during continuous infusion of 10-ml water one minute three times. Respiratory phases and swallowing were monitored using electrocardiogram (EKG)-derived respiratory signals and submental electromyography (EMG), respectively. The swallowing frequency and timing of swallows in relation to respiratory phases were recorded. The coordination between swallowing and respiration was classified into 4 patterns, namely I, E, I-E, and E-I swallows. (I; inspiration and E; expiration) Subsequently, after a 5-min washout period, the patients were switched to the other type of oxygen therapy using the same procedure. The Wilcoxon Signed-Rank Test was used for statistical analysis. A total of 22 patients with a mean age of 56 years were enrolled in the study. The major indication for invasive mechanical ventilation was pneumonia with a median duration of endotracheal intubation of 2.5 days. The median total swallowing numbers (three minutes) were 18.5 times in the HFNO period and 21 times in the LFNO period (p = NS). The most common swallowing pattern was E-swallow. The patients using HFNO had higher numbers of E-swallow pattern (74.3% in HFNO vs 67.6% in LFNO; p = 0.048) and lower numbers of I-swallow pattern (14.3% in HFNO vs 23.1% in LFNO; p = 0.044). The numbers of other swallowing patterns were not different between the 2 groups. Compared with LFNO, HFNO significantly increased the E-swallow and decreased the I-swallow in post-extubation patients. The findings indicated that HFNO might reduce a risk of aspiration during the post-extubation period. Clinical trial No.: Thai clinical trial TCTR20200206004 Registered February 4, 2020. URL: http://www.clinicaltrials.in.th/index.php?tp=regtrials&menu=trialsearch&smenu=fulltext&task=search&task2=view1&id=5740 .

中文翻译：

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高流量鼻导管对拔管后患者吞咽和呼吸协调的影响，随机交叉研究

与呼吸阶段相关的吞咽时间与吸入事件有关。氧气治疗可能会影响吞咽的时间，这可能会改变气道保护机制。比较使用高流量鼻氧 (HFNO) 的拔管后患者输液过程中吞咽和呼吸之间的协调与使用低流量鼻氧 (LFNO) 的患者的协调。我们对拔管后患者进行了一项随机对照交叉研究。48 h内拔管的患者随机分为HFNO和LFNO两组。每组中符合条件的患者接受吸入氧分数 (FiO2) 0.35、流量 50 L/分钟 (LPM) 和温度 34 °C 的 HFNO 或 LFNO 5 LPM 5 分钟。在连续输注 10 毫升水 1 分钟 3 次期间观察吞咽和呼吸之间的协调。分别使用心电图 (EKG) 衍生的呼吸信号和颏下肌电图 (EMG) 监测呼吸相位和吞咽。记录与呼吸阶段相关的吞咽频率和吞咽时间。吞咽与呼吸协调分为I、E、IE、EI吞咽4种模式。（I；吸气和 E；呼气） 随后，在 5 分钟的冲洗期后，患者使用相同的程序切换到其他类型的氧疗。Wilcoxon 符号秩检验用于统计分析。共有 22 名平均年龄为 56 岁的患者参加了该研究。有创机械通气的主要适应症是肺炎，气管插管的中位时间为 2.5 天。HFNO 期间的中位总吞咽次数（3 分钟）为 18.5 倍，LFNO 期间为 21 倍（p = NS）。最常见的吞咽模式是电子吞咽。使用 HFNO 的患者 E 吞咽模式数量较多（HFNO 为 74.3%，LFNO 为 67.6%；p = 0.048）和 I 吞咽模式数量较少（HFNO 为 14.3% vs LFNO 为 23.1%；p = 0.044） . 两组之间其他吞咽模式的数量没有差异。与 LFNO 相比，HFNO 显着增加了拔管后患者的 E 吞咽和 I 吞咽。研究结果表明，HFNO 可能会降低拔管后期间误吸的风险。临床试验编号：