Department of Emergency and Critical Care Medicine, University of Tokushima Graduate School.
Respir Care. 2014 Jan;59(1):70-4. doi: 10.4187/respcare.02480. Epub 2013 Jun 4.
High-flow nasal cannula (HFNC) creates positive oropharyngeal airway pressure and improves oxygenation. It remains unclear, however, whether HFNC improves thoraco-abdominal synchrony in patients with mild to moderate respiratory failure. Using respiratory inductive plethysmography, we investigated the effects of HFNC on thoraco-abdominal synchrony.
We studied 40 adult subjects requiring oxygen therapy in the ICU. Low-flow oxygen (up to 8 L/min) was administered via oronasal mask for 30 min, followed by HFNC at 30-50 L/min. Respiratory inductive plethysmography transducer bands were circumferentially placed: one around the rib cage, and one around the abdomen. We measured the movement of the rib-cage and abdomen, and used the sum signal to represent tidal volume (V(T)) during mask breathing, and at 30 min during HFNC. We calculated the ratio of maximum compartmental amplitude (MCA) to V(T), and the phase angle. We assessed arterial blood gas and vital signs at each period, and mouth status during HFNC. We used multiple regression analysis to identify factors associated with improvement in thoraco-abdominal synchrony.
During HFNC, breathing frequency significantly decreased from 25 breaths/min (IQR 22-27 breaths/min) to 21 breaths/min (IQR 18-24 breaths/min) (P < .001), and MCA/VT (P < .001) and phase angle (P = .047) significantly improved.
HFNC improved thoraco-abdominal synchrony in adult subjects with mild to moderate respiratory failure.
高流量鼻导管（HFNC）可产生正压口咽通气，并改善氧合。然而，HFNC 是否能改善轻度至中度呼吸衰竭患者的胸腹同步性尚不清楚。我们使用呼吸感应容积描记法研究了 HFNC 对胸腹同步性的影响。
我们研究了 40 名需要在 ICU 中接受氧疗的成年患者。通过口鼻面罩给予低流量氧气（最高 8 L/min）30 分钟，然后以 30-50 L/min 的流量给予 HFNC。呼吸感应容积描记法传感器带环绕放置：一个围绕肋骨，一个围绕腹部。我们测量了肋骨和腹部的运动，并使用总和信号来表示面罩呼吸时的潮气量（V(T)），以及 HFNC 时的 30 分钟时的 V(T)。我们计算了最大隔室幅度（MCA）与 V(T)的比值和相位角。我们在每个时期评估了动脉血气和生命体征，以及 HFNC 期间的口腔状况。我们使用多元回归分析来确定与胸腹同步性改善相关的因素。
在 HFNC 期间，呼吸频率从 25 次/分钟（IQR 22-27 次/分钟）显著下降至 21 次/分钟（IQR 18-24 次/分钟）（P<0.001），MCA/VT（P<0.001）和相位角（P=0.047）显著改善。
HFNC 改善了轻度至中度呼吸衰竭成年患者的胸腹同步性。
