BACKGROUND: High-flow nasal oxygen (HFNO), or transnasal humidified rapid-insufflation ventilatory exchange (THRIVE), is a technique providing apneic oxygenation and a degree of ventilation during microlaryngeal surgery. Its use with laser has been questioned due to concern for airway fire. For fire to occur, a triad of ignition source, oxidizer, and fuel source must be present. By using HFNO and eliminating an endotracheal tube (fuel source), it is hypothesized that airway fire risk is minimal. We tested this theory with human cadavers using HFNO with increasing levels of FiO2 while performing microlaryngeal laser surgery.
METHODS: HFNO was placed on two cadavers, and oxygen was administered at incrementally increasing fraction of inspired oxygen (FiO2) concentrations (30%-100%). Laryngeal microsurgery was conducted with CO2 and KTP lasers applied for 30 s. Oxygen readings were taken at several anatomic locations along the body assessing oxygen concentrations in correlation with increasing FiO2 administration.
RESULTS: The use of CO2 and KTP laser on cadaveric vocal folds produced char but no spark or airway fire at any of the tested oxygen concentrations. Apart from the mouth, there was minimal increase in oxygen levels at the surrounding anatomic sites despite elevating FiO2 levels.
CONCLUSIONS: HFNO may be safe to use during microlaryngeal laser surgery. By eliminating the endotracheal tube as a fuel source, risk of airway fire may be negligible. Our study safely applied CO2 and KTP lasers for an uninterrupted 30 s with HFNO at 70 L/min and 100% FiO2 producing no spark or fire.
METHODS: NA Laryngoscope, 2024.

BACKGROUND: COVID-19 is a viral infection affecting the respiratory system, primarily. It has spread globally ever since it first appeared in China in 2019. The use of high-flow nasal oxygen (HFNO) for the treatment of COVID-19 has not been well established.
OBJECTIVE: The primary objectives of this study are to observe the success of HFNO in preventing escalation to mechanical ventilation (MV) and to measure the prevalence of HFNO in King Abdulaziz Medical City (KAMC). The secondary objective is to describe patients who received HFNO clinically.
METHODS: This is a retrospective cohort study of all polymerase chain reaction (PCR)-confirmed COVID-19 patients who require oxygen therapy in KAMC, Jeddah between March 1st, 2020, and December 31st, 2020. Any patients requiring MV on admission were excluded.
RESULTS: 259 patients fit the inclusion criteria, and 25.5% of those included received HFNO. The number of non-survivors is 47 (18.1%). Mortality for HFNO, MV, and intensive care unit (ICU) are 30 (45.5%), 31 (60.8%), and 24 (32%), respectively. Their demographic was as follows; 160 were males, with a mean age of 60.93±15.01. Regarding the types of oxygen, low-flow nasal oxygen (LFNO) was administered to 243 out of the 259 patients, 66 received HFNO, 42 received MV, and 49 received other modes of ventilation. Additionally, 43.9% received HFNO escalated to MV. Patients who did not receive HFNO or MV were 178 (68.7%) in total.
CONCLUSIONS: The use of HFNO in COVID-19 patients could show better outcomes than MV in addition to preventing the use of MV. Larger studies are required to determine the efficacy of HFNO in COVID-19 patients.

Restricted mouth opening is a challenging airway in pediatric patients with temperomandibular joint (TMJ) ankylosis. The fiber-optic bronchoscopic nasotracheal intubation technique continues to be the gold standard for difficult airway, among the techniques available such as submandibular intubation, retrograde intubation, and tracheostomy. However, awake fiber-optic bronchoscopy (FOB) is difficult to achieve in pediatric patients. Prior planning of the anesthetic method and effective collaboration with the surgeon are crucial for excellent outcomes in such challenging airway cases. We present a successful awake fiber-optic bronchoscopy with high-flow nasal oxygen (HFNO), airway blocks, and deep sedation in the case of bilateral TMJ ankylosis of a pediatric age group with reduced mouth opening. We conclude that awake intubation using HFNO and airway blocks helps to achieve oxygenation and ease of intubation in difficult airway management.

BACKGROUND: Highflow nasal cannula oxygen (HFNO) is known to be used for noninvasive oxygenation in intensive care patients but it has rarely been used in airway management for elective surgery of the upper aerodigestive tract.
OBJECTIVE: HFNO offers opportunities of a tubeless oxygenation system which is easy to handle and not limited only on surgery of the endolarynx.
METHODS: We evaluated this method for oxygenation during brief interventional procedures of the larynx and pharynx in 92 adult patients for safety and intraoperative complications. The need of secondary endotracheal intubation and limiting comorbidities as pulmonal and cardiac diseases were documented.
RESULTS: HFNO showed a good safety profile concerning saturation and hypercapnia. Oxygen desaturation below 90% occurred only in 5 patients, mask ventilation led to quick recovery except in one patient who was secondary intubated. A significant influence of the body mass index on the minimal O2 saturation was shown (p < 0,001) so that a possible limitation of the method exists here. Comorbidities were grouped into the ASA classification. There was a significant difference between ASA I/II and ASA III patients in terms of minimum O2saturation.
CONCLUSIONS: We conclude that HFNO may hold great promise for changing ventilator technique in general anesthesia, particularly in short elective laryngeal and pharyngeal surgery. Safety and feasibility were proven in this study.

Pulmonary insufficiency is the primary cause of death in cases of major burns accompanied by inhalation damage. It is important to consider the impact on the face and neck in flame burns. Early implementation of bronchial hygiene measures and oxygenation treatment in inhalation injury can reduce mortality. This case series presents the effects of high-flow nasal oxygen (HFNO) application on patient outcomes in major burns and inhalation injury. This report discusses 3 different patients. One patient, a 29-year-old male with 35% TBSA burns, received HFNO treatment for inhalation injury on the sixth day after the trauma. After 72 hours of HFNO application, the patient\'s pulmonary symptoms improved. The second patient had 60% TBSA burns and developed respiratory distress symptoms on the fifth day after the trauma. After 7 days of HFNO application, all symptoms and findings of acute respiratory distress syndrome (ARDS) were resolved. HFNO has been used for the treatment of ARDS related to major burn (60% of burned TBSA) in a 28-year-old patient, and improvement was achieved. The use of HFNO in pulmonary insufficiency among burn patients has not been reported previously. This series of patient cases demonstrates the successful application of HFNO in treating inhalation injury and burn-related ARDS. However, further clinical studies are necessary to increase its clinical utilization.

暂无摘要。

OBJECTIVE: Hypoxia is a frequently reported complication during the intubation procedure in the emergency department (ED) and may cause bad outcomes. Therefore, oxygenation plays an important role in emergency airway management. The efficacy of oxygenation with high-flow nasal cannula (HFNC) in the ED has been studied, though the evidence is limited. The study aim was to compare two methods of preoxygenation in patients undergoing rapid sequence intubation (RSI) in the ED: (1) HFNC and (2) bag-valve mask (BVM) oxygenation.
METHODS: This is a single-center, prospective, randomized controlled trial (RCT) in adult ED patients requiring RSI. Patients were randomized to receive preoxygenation with either HFNC or BVM. While HFNC therapy was continued during the intubation procedure, BVM oxygenation was interrupted for laryngoscopy. The primary outcome was the lowest peripheral oxygen saturation (SpO2) level during intubation. Secondary outcomes were incidence of desaturation (SpO2<90%) and severe hypoxemia (SpO2<80%) throughout the procedure, intubation time, rate of failed intubation, and 30-day survival rates.
RESULTS: A total of 135 patients were randomized into two groups (HFNC n = 68; BVM n = 67). The median lowest SpO2 value measured during intubation was 96% (88.8%-99.0%) in the HFNC group and 92% (86.0%-97.5%) in the BVM group (P = .161). During the intubation procedure, severe hypoxemia occurred in 13.2% (n = 9) of patients in the HFNC group and 8.9% (n = 6) in the BVM group, while mild hypoxemia was observed in 35.8% (n = 24) of the BVM group and 26.5% (n = 18) of the HFNC group. However, there was no statistically significant difference between the groups in terms of hypoxemia development (P = .429 and P = .241, respectively). No significant difference was reported in the rate of failed intubation between the groups. Thirty-day mortality was observed in 73.1% of the BVM group and 57.4% of the HFNC group, with a borderline statistically significant difference (difference 15.7; 95% CI of the difference: -0.4 to 30.7; P = .054).
CONCLUSIONS: The use of HFNC for preoxygenation, when compared to standard care with BVM oxygenation, did not improve the lowest SpO2 levels during intubation. Also, the use of HFNC during intubation did not provide benefits in reducing the incidence of severe hypoxemia. However, the 30-day survival rates were slightly better in the HFNC group compared to the BVM group.

The use of the Ratio of Oxygen Saturation (ROX) index to predict the success of high-flow nasal oxygenation (HFNO) is well established. The ROX can also predict the need for intubation, mortality, and is easier to calculate compared with APACHE II. In this prospective study, the primary aim is to compare the ROX (easily administered in resource limited setting) to APACHE II for clinically relevant outcomes such as mortality and the need for intubation. Our secondary aim was to identify thresholds for the ROX index in predicting outcomes such as the length of ICU stay and failure of non-invasive respiratory support therapies and to assess the effectiveness of using the ROX (day 1 at admission, day 2, and day 3) versus Acute physiology and chronic health evaluation (APACHE) II scores (at admission) in patients with Coronavirus Disease 2019 (COVID-19) pneumonia and Acute Respiratory Distress Syndrome (ARDS) to predict early, late, and non-responders. After screening 208 intensive care unit patients, a total of 118 COVID-19 patients were enrolled, who were categorized into early (n = 38), late (n = 34), and non-responders (n = 46). Multinomial logistic regression, receiver operating characteristic (ROC), Multivariate Cox regression, and Kaplan-Meier analysis were conducted. Multinomial logistic regressions between late and early responders and between non- and early responders were associated with reduced risk of treatment failures. ROC analysis for early vs. late responders showed that APACHE II on admission had the largest area under the curve (0.847), followed by the ROX index on admission (0.843). For responders vs. non-responders, we found that the ROX index on admission had a slightly better AUC than APACHE II on admission (0.759 vs. 0.751). A higher ROX index on admission [HR (95% CI): 0.29 (0.13-0.52)] and on day 2 [HR (95% CI): 0.55 (0.34-0.89)] were associated with a reduced risk of treatment failure. The ROX index can be used as an independent predictor of early response and mortality outcomes to HFNO and NIV in COVID-19 pneumonia, especially in low-resource settings, and is non-inferior to APACHE II.

BACKGROUND: The objective of this study is to assess the failure of therapies with HFNO (high-flow nasal oxygen), CPAP, Bilevel, or combined therapy in patients with hypoxemic acute respiratory failure due to SARS-CoV-2 during their hospitalization.
METHODS: This was a retrospective and observational study of SARS-CoV-2-positive patients who required non-invasive respiratory support (NIRS) at the Reina Sofía General University Hospital of Murcia between March 2020 and May 2021.
RESULTS: Of 7355 patients, 197 (11.8%) were included; 95 of them failed this therapy (48.3%). We found that during hospitalization in the ward, the combined therapy of HFNO and CPAP had an overall lower failure rate and the highest treatment with Bilevel (p = 0.005). In the comparison of failure in therapy without two levels of airway pressure, HFNO, CPAP, and combined therapy of HFNO with CPAP, (35.6% of patients) presented with 24.2% failure, compared to those who had two levels of pressure with Bilevel and combined therapy of HFNO with Bilevel (64.4% of patients), with 75.8% associated failure (OR: 0, 374; CI 95%: 0.203-0.688. p = 0.001).
CONCLUSIONS: The use of NIRS during conventional hospitalization is safe and effective in patients with respiratory failure secondary to SARS-CoV-2 infection. The therapeutic strategy of Bilevel increases the probability of failure, with the combined therapy strategy of CPAP and HFNO being the most promising option.

BACKGROUND: In COVID-19 patients, older age (sixty or older), comorbidities, and frailty are associated with a higher risk for mortality and invasive mechanical ventilation (IMV) failure. It therefore seems appropriate to suggest limitations of care to older and vulnerable patients with severe COVID-19 pneumonia and a poor expected outcome, who would not benefit from invasive treatment. HFNO (high flow nasal oxygen) is a non-invasive respiratory support device already used in de novo acute respiratory failure. The main objective of this study was to evaluate the survival of patients treated with HFNO outside the ICU (intensive care unit) for a severe COVID-19 pneumonia, otherwise presenting limitations of care making them non-eligible for IMV. Secondary objectives were the description of our cohort and the identification of prognostic factors for HFNO failure.
METHODS: We conducted a retrospective cohort study. We included all patients with limitations of care making them non-eligible for IMV and treated with HFNO for a severe COVID-19 pneumonia, hospitalized in a COVID-19 unit of the pulmonology department of Lyon Sud University Hospital, France, from March 2020 to March 2021. Primary outcome was the description of the vital status at day-30 after HFNO initiation, using the WHO (World Health Organization) 7-points ordinal scale.
RESULTS: Fifty-six patients were included. Median age was 83 years [76.3-87.0], mean duration for HFNO was 7.5 days, 53% had a CFS score (Clinical Frailty Scale) >4. At day-30, 73% of patients were deceased, one patient (2%) was undergoing HFNO, 9% of patients were discharged from hospital. HFNO failure occurred in 66% of patients. Clinical signs of respiratory failure before HFNO initiation (respiratory rate >30/min, retractions, and abdominal paradoxical breathing pattern) were associated with mortality (p = 0.001).
CONCLUSIONS: We suggest that HFNO is an option in non-ICU skilled units for older and frail patients with a severe COVID-19 pneumonia, otherwise non-suitable for intensive care and mechanical ventilation. Observation of clinical signs of respiratory failure before HFNO initiation was associated with mortality.