The effect of high-flow nasal cannula on diaphragm dysfunction including paradoxical diaphragmatic contraction in the intensive care unit

Abstract

Background : Diaphragm dysfunction is a serious problem. However, a few management techniques exist for diaphragm dysfunction. Methods : Adult patients treated with high-flow nasal cannula (HFNC) in the intensive care unit were included in this study. The diaphragm function was evaluated using ultrasound measurement of thickening fraction before and after HFNC liberation. Normal diaphragm contraction was defined as thickening fraction ≥ 15% without HFNC, whereas decreased or paradoxical diaphragm contractions were 0%-15% or < 0%, respectively. Results : Forty patients were enrolled, and 16 (40%) had normal diaphragm contraction, whereas 19 (48%) or 5 (13%) had decreased or paradoxical diaphragm contractions, respectively. Thickening fraction increased after HFNC liberation (27.0% ± 25.7% vs. 38.8% ± 34.5%, p = 0.03 in HFNC vs. no HFNC) in patients without diaphragm dysfunction. In patients with decreased diaphragm contraction, thickening fraction did not change with or without HFNC (8.9% ± 11.7% vs. 6.7% ± 5.2%, p = 0.35), whereas paradoxical contraction decreased with HFNC (1.0% ± 10.2% vs. -10.3% ± 2.7%, p = 0.04) in patients with paradoxical diaphragm contraction. Conclusions : The work of breathing decreased with HFNC in patients without diaphragm dysfunction, but did not decrease in patients with decreased diaphragm contraction. Paradoxical diaphragm contraction decreased with HFNC.

The effect of high-flow oxygen via tracheostomy on respiratory pattern and diaphragmatic function in patients with prolonged mechanical ventilation: A randomized, physiological, crossover study

“…Indeed, the effect of HFOT on diaphragmatic function has been rarely investigated even in patients with HFOT via the nasal route. [29] , [30] , [31] In the study by Longini et al [29] in patients recovering from hypercapnic acute respiratory failure, the application of HFOT at 50 L/min after noninvasive ventilation interruption did not change diaphragmatic displacement, regardless of the modality of oxygen administration. On the contrary, the application of HFOT with progressively increasing intensity of set flow increased diaphragmatic excursion and lung volume, wherein the latter was measured by electrical impedance tomography in a study published only in abstract form.…”

“…The diaphragmatic thickening fraction has been measured unchanged or increased during HFOT. [29] , [30] Indeed, the diaphragmatic thickening fraction remained unchanged during HFOT or noninvasive ventilation in a crossover trial in COPD patients recovering from an exacerbation. [29] Similarly, in ICU patients receiving HFOT through a nasal cannula, the diaphragmatic thickening fraction increased with HFOT in patients without diaphragm dysfunction, whereas it did not change with HFOT in patients with impaired diaphragm contraction (defined as diaphragmatic thickening fraction <15%).…”

“… [29] Similarly, in ICU patients receiving HFOT through a nasal cannula, the diaphragmatic thickening fraction increased with HFOT in patients without diaphragm dysfunction, whereas it did not change with HFOT in patients with impaired diaphragm contraction (defined as diaphragmatic thickening fraction <15%). [30] …”