High-Flow Nasal Interface Improves Oxygenation in Patients Undergoing Bronchoscopy

Abstract

During bronchoscopy hypoxemia is commonly found and oxygen supply can be delivered by interfaces fed with high gas flows. Recently, the high-flow nasal cannula (HFNC) has been introduced for oxygen therapy in adults, but they have not been used so far during bronchoscopy in adults. Forty-five patients were randomly assigned to 3 groups receiving oxygen: 40 L/min through a Venturi mask (V40, N = 15), nasal cannula (N40, N = 15), and 60 L/min through a nasal cannula (N60, N = 15) during bronchoscopy. Gas exchange and circulatory variables were sampled before (FiO2 = 0.21), at the end of bronchoscopy (FiO2 = 0.5), and thereafter (V40, FiO2 = 0.35). In 8 healthy volunteers oxygen was randomly delivered according to V40, N40, and N60 settings, and airway pressure was measured. At the end of bronchoscopy, N60 presented higher PaO2, PaO2/FiO2, and SpO2 than V40 and N40 that did not differ between them. In the volunteers (N60) median airway pressure amounted to 3.6 cmH2O. Under a flow rate of 40 L/min both the Venturi mask and HFNC behaved similarly, but nasal cannula associated with a 60 L/min flow produced the better results, thus indicating its use in mild respiratory dysfunctions.

High-Flow Nasal Cannula Versus Conventional Oxygen Therapy After Endotracheal Extubation: A Randomized Crossover Physiologic Study

“…Sztrymf et al 16,17 found that HFNC significantly reduced breathing frequency, heart rate, dyspnea score, supraclavicular retraction, and thoraco-abdominal synchrony and increased pulse oximetry in 38 ICU patients with acute respiratory failure; this improvement was observed as early as 15 min after the beginning of HFNC. This result was consistent with 19 during invasive procedures such as bronchoscopy, 20 and do-not-intubate patients. 21 As in this study the subjects showed relatively low levels of dyspnea (dyspnea score of Ͻ 3 points), low breathing frequency (Ͻ 25 breaths/min), and low heart rate (Ͻ 100 beats/min), one could argue that similar results may have been achieved with only the conventional oxygen therapy.…”

Use of High-Flow Nasal Cannula for Acute Dyspnea and Hypoxemia in the Emergency Department

“…The advantage of HFNC in terms of improving dyspnea, subject comfort, and oxygenation has also been noted in other subject populations, such as post-cardiac surgery 8 and postendotracheal extubation subjects, 7,9 and during fiberoptic bronchoscopy. 24 Several studies demonstrated that HFNC reduced breathing frequency and also improved oxygenation in subjects Fig. 2.…”

Nasal high flow therapy: a novel treatment rather than a more expensive oxygen device

“…) protect patients from hypoxaemia during bronchoscopy with remarkable tolerance and minimal variations in SpO 2 [77][78][79][80]. NIV and CPAP are usually used in more severe hypoxaemic patients during bronchoscopy and studies have shown that NIV is superior both to SOT [81][82][83] and to NHF [84].…”

“…NIV and CPAP are usually used in more severe hypoxaemic patients during bronchoscopy and studies have shown that NIV is superior both to SOT [81][82][83] and to NHF [84]. Moreover, it seems that NHF benefits are more remarkable when bronchoscopy is performed through the nares than through the mouth; nonetheless, even if bronchoscopy is performed through the mouth, maximum flow rate (60 L·min ) should be used, since a PEEP value of 3.6 cmH 2 O has been measured at this flow rate in healthy volunteers with a partially obstructed mouth [77].…”