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

Abstract

OBJECTIVE: Compare the short-term benefit of high-flow nasal cannula (HFNC) with nonrebreathing mask in terms of change in dyspnea, physiologic variables, and patient comfort in subjects after endotracheal extubation. METHODS: A randomized crossover study was conducted in a 10-bed respiratory care unit in a university hospital. Seventeen mechanically ventilated subjects were randomized after extubation to either Protocol A (applied HFNC for 30 min, followed by non-rebreathing mask for another 30 min) or Protocol B (applied non-rebreathing mask for 30 min, followed by HFNC for another 30 min). The level of dyspnea, breathing frequency, heart rate, blood pressure, oxygen saturation, and patient comfort were recorded. The results were expressed as mean ؎ SD, frequency, or percentage. Categorical variables were compared by chi-square test or Fisher exact test, and continuous variables were compared by dependent or paired t test. Statistical significance was defined as P < .05. RESULTS: Seventeen subjects were divided into 2 groups: 9 subjects in Protocol A and 8 subjects in Protocol B. The baseline characteristics and physiologic parameters before extubation were not significantly different in each protocol. At the end of study, HFNC indicated less dyspnea (P ‫؍‬ .04) and lower breathing frequency (P ‫؍‬ .009) and heart rate (P ‫؍‬ .006) compared with non-rebreathing mask. Most of the subjects (88.2%) preferred HFNC to non-rebreathing mask. CONCLUSIONS: HFNC can improve dyspnea and physiologic parameters, including breathing frequency and heart rate, in extubated subjects compared with conventional oxygen therapy. This device may have a potential role for use after endotracheal extubation.

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

“…Moreover, the use of NHF in the post-extubation period was associated with less need for NIV and endotracheal intubation than the Venturi mask (7.5% versus 34.6%) [35]. Both these studies [34,35] support the protective role of NHF after extubation, attributing this effect to higher flow of the administered gas with the NHF system, which could meet the ventilator demand of the patient after extubation. Given the fact that the patients included in these studies [34,35] had residual respiratory impairment, these results could not be generalised to the overall population.…”

“…Both these studies [34,35] support the protective role of NHF after extubation, attributing this effect to higher flow of the administered gas with the NHF system, which could meet the ventilator demand of the patient after extubation. Given the fact that the patients included in these studies [34,35] had residual respiratory impairment, these results could not be generalised to the overall population. Indeed, even in patients at low risk of re-intubation, NHF successfully reduced re-intubation rates from 12.2% [36,37] to 4.9%, compared to SOT devices, without any reported complications, which was attributed to NHF-favourable mechanisms on the work of breathing and the conditioning of the inspired gas, even at high flow rates [38].…”

“…SOT devices are used to treat this complication, but they may be inadequate in patients with high inspiratory flow, since they can provide oxygen at flow rates <15 L·min −1 [21,32,33]. RITTAYAMAI et al [34], in a crossover study, compared 30-min interventions with NHF and a non-rebreathing mask in recently extubated patients. They reported significant reductions in dyspnoea, respiratory rate and heart rate with NHF [34].…”

“…RITTAYAMAI et al [34], in a crossover study, compared 30-min interventions with NHF and a non-rebreathing mask in recently extubated patients. They reported significant reductions in dyspnoea, respiratory rate and heart rate with NHF [34]. These results were further confirmed and strengthened by another study comparing NHF with the Venturi mask in critically ill patients requiring oxygen therapy after extubation (PaO 2 /FiO 2 <300) [35].…”

High Flow Nasal Oxygen Therapy: From Physiology to Clinic

“…A decrease in the respiration rate and heart rate was detected first in the HFNO group. Dyspnea scores 30 min after the start of treatment were found to be lower in the HFNO group, and an increase in patient comfort was also noted (49). In the study comparing the clinical effects of HFNO and NRM after extubation, the mean PaO 2 /FiO 2 ratio was significantly increased in the HFNO group and a faster recovery (270 vs. 183 mmHg, p<0.0001) was observed in oxygenation with HFNO.…”