Effect of noninvasive ventilation on mortality and clinical outcomes among patients with severe hypoxemic COVID-19 pneumonia after high-flow nasal oxygen failure: a multicenter retrospective French cohort with propensity score analysis.

BACKGROUND: We assessed the effect of noninvasive ventilation (NIV) on mortality and length of stay after high flow nasal oxygenation (HFNO) failure among patients with severe hypoxemic COVID-19 pneumonia. METHODS: In this multicenter, retrospective study, we enrolled COVID-19 patients admitted in intensive care unit (ICU) for severe COVID-19 pneumonia with a HFNO failure from December 2020 to January 2022. The primary outcome was to compare the 90-day mortality between patients who required a straight intubation after HFNO failure and patients who received NIV after HFNO failure. Secondary outcomes included ICU and hospital length of stay. A propensity score analysis was performed to control for confounding factors between groups. Exploratory outcomes included a subgroup analysis for 90-day mortality. RESULTS: We included 461 patients with HFNO failure in the analysis, 233 patients in the straight intubation group and 228 in the NIV group. The 90-day mortality did not significantly differ between groups, 58/228 (25.4%) int the NIV group compared with 59/233 (25.3%) in the straight intubation group, with an adjusted hazard ratio (HR) after propensity score weighting of 0.82 [95%CI, 0.50-1.35] (p = 0.434). ICU length of stay was significantly shorter in the NIV group compared to the straight intubation group, 10.0 days [IQR, 7.0-19.8] versus 18.0 days [IQR,11.0-31.0] with a propensity score weighted HR of 1.77 [95%CI, 1.29-2.43] (p < 0.001). A subgroup analysis showed a significant increase in mortality rate for intubated patients in the NIV group with 56/122 (45.9%), compared to 59/233 (25.3%) for patients in the straight intubation group (p < 0.001). CONCLUSIONS: In severely hypoxemic COVID-19 patients, no significant differences were observed on 90-day mortality between patients receiving straight intubation and those receiving NIV after HFNO failure. NIV strategy was associated with a significant reduction in ICU length of stay, despite an increase in mortality in the subgroup of patients finally intubated.

Dyspnea is severe and associated with a higher intubation rate in de novo acute hypoxemic respiratory failure.

BACKGROUND: Dyspnea is a key symptom of de novo acute hypoxemic respiratory failure. This study explores dyspnea and its association with intubation and mortality in this population. METHODS: This was a secondary analysis of a multicenter, randomized, controlled trial. Dyspnea was quantified by a visual analog scale (dyspnea-VAS) from zero to 100 mm. Dyspnea was measured in 259 of the 310 patients included. Factors associated with intubation were assessed with a competing risks model taking into account ICU discharge. The Cox model was used to evaluate factors associated with 90-day mortality. RESULTS: At baseline (randomization in the parent trial), median dyspnea-VAS was 46 (interquartile range, 16-65) mm and was ≥ 40 mm in 146 patients (56%). The intubation rate was 45%. Baseline variables independently associated with intubation were moderate (dyspnea-VAS 40-64 mm) and severe (dyspnea-VAS ≥ 65 mm) dyspnea at baseline (sHR 1.96 and 2.61, p = 0.023), systolic arterial pressure (sHR 2.56, p < 0.001), heart rate (sHR 1.94, p = 0.02) and PaO2/FiO2 (sHR 0.34, p = 0.028). 90-day mortality was 20%. The cumulative probability of survival was lower in patients with baseline dyspnea-VAS ≥ 40 mm (logrank test, p = 0.049). Variables independently associated with mortality were SAPS 2 ≥ 25 (p < 0.001), moderate-to-severe dyspnea at baseline (p = 0.073), PaO2/FiO2 (p = 0.118), and treatment arm (p = 0.046). CONCLUSIONS: In patients admitted to the ICU for de novo acute hypoxemic respiratory failure, dyspnea is associated with a higher risk of intubation and with a higher mortality. TRIAL REGISTRATION: clinicaltrials.gov Identifier # NCT01320384.

Impact of high-flow nasal oxygen therapy on postoperative atelectasis and reintubation rate after paediatric cardiac surgery.

INTRODUCTION: Airway problems emerging after congenital cardiac surgery operations may have an impact on mortality and morbidity. Recently, to improve alveolar gas exchange and reduce respiratory effort, high-flow nasal cannula (HFNC) has started to be used in paediatric cases. This study aimed to evaluate the potential effects of high-flow nasal oxygen therapy on postoperative atelectasis development and reintubation rate in paediatric cardiac surgery patients. METHODS: This study was conducted retrospectively in term newborns and infants younger than six months of age who underwent congenital cardiac surgery operation from 1 November 2022 to 1 November 2023 and were followed in the paediatric cardiac ICU. Patients who were receiving mechanical ventilator support at least 12 hours postoperatively were evaluated for the development of postoperative atelectasis and reintubation in the first 3 days of extubation. The patients were grouped as HFNC and non-HFNC users. Demographic characteristics, surgery type, and ICU clinical follow-up data were obtained from medical records. The results were statistically evaluated. RESULTS: A total of 40 patients who did not use HFNC in the early postoperative period and 40 patients with HFNC in the late period during the study period were included in the study. The median age was 1 month (IQR 15 days-2 months) with equal gender distribution. Among patients, 70% of them were in the neonatal age group. Reintubation rates in the first 72 hours in HFNC users and non-HFNC users were 2.5% and 12.5%, respectively (p < 0.05). The median postoperative atelectasis scores at 24, 48, and 72 hours of extubation were 2 versus 2.5 (p > 0.05), 1.5 versus 3.5 (p < 0.05), and 1 versus 3 (p < 0.05) in HFNC users and non-HFNC users, respectively. CONCLUSION: HFNC therapy may have a positive effect on preventing atelectasis and reducing the reintubation rate in the early postoperative period.

High-Flow Versus VenturiMask Oxygen Therapy to Prevent Reintubation in Hypoxemic Patients after Extubation: A Multicenter Randomized Clinical Trial.

Rationale: When compared with VenturiMask after extubation, high-flow nasal oxygen provides physiological advantages. Objectives: To establish whether high-flow oxygen prevents endotracheal reintubation in hypoxemic patients after extubation, compared with VenturiMask. Methods: In this multicenter randomized trial, 494 patients exhibiting PaO2:FiO2 ratio ⩽ 300 mm Hg after extubation were randomly assigned to receive high-flow or VenturiMask oxygen, with the possibility to apply rescue noninvasive ventilation before reintubation. High-flow use in the VenturiMask group was not permitted. Measurements and Main Results: The primary outcome was the rate of reintubation within 72 hours according to predefined criteria, which were validated a posteriori by an independent adjudication committee. Main secondary outcomes included reintubation rate at 28 days and the need for rescue noninvasive ventilation according to predefined criteria. After intubation criteria validation (n = 492 patients), 32 patients (13%) in the high-flow group and 27 patients (11%) in the VenturiMask group required reintubation at 72 hours (unadjusted odds ratio, 1.26 [95% confidence interval (CI), 0.70-2.26]; P = 0.49). At 28 days, the rate of reintubation was 21% in the high-flow group and 23% in the VenturiMask group (adjusted hazard ratio, 0.89 [95% CI, 0.60-1.31]; P = 0.55). The need for rescue noninvasive ventilation was significantly lower in the high-flow group than in the VenturiMask group: at 72 hours, 8% versus 17% (adjusted hazard ratio, 0.39 [95% CI, 0.22-0.71]; P = 0.002) and at 28 days, 12% versus 21% (adjusted hazard ratio, 0.52 [95% CI, 0.32-0.83]; P = 0.007). Conclusions: Reintubation rate did not significantly differ between patients treated with VenturiMask or high-flow oxygen after extubation. High-flow oxygen yielded less frequent use of rescue noninvasive ventilation. Clinical trial registered with www.clinicaltrials.gov (NCT02107183).

Efficacy of a surgical mask during high-flow nasal oxygen therapy in preventing aerosol dispersion: a randomized controlled study.

PURPOSE: It is not clear whether or not high-flow nasal oxygenation used in patients with severe respiratory tract infection, or coughing, increases the risk of infection to the healthcare personnel, and whether or not applying a surgical mask to the patient's face or treating the patient in a negative-pressure room can reduce the risk. METHODS: In a randomized crossover design, we compared in 50 participants receiving high-flow nasal oxygenation, the aerosol counts measured at approximately 20 cm above the participant's mouth in 32 different circumstances (with or without coughing, with or without wearing a surgical mask, at four different flow rates of oxygenation, in a positive- or negative-pressure operating room). RESULTS: In a positive-pressure room, a surgical mask significantly decreased the aerosol counts during coughing (P = 0.0005), or during no coughing (P = 0.009), under high-flow nasal oxygenation (at 60 l.min-1). In the negative-pressure room, the aerosol count was significantly lower than in the positive-pressure room, for all the circumstances (all P < 0.001), and a surgical mask significantly decreased the aerosol counts during coughing (P = 0.047) but not during no coughing (P = 0.60). CONCLUSION: In conclusion, treating a patient in a negative-pressure room, or applying a surgical mask, during high-flow nasal oxygenation (with the flow rate of 60 l.min-1) would inhibit, but would not completely prevent, dispersion of aerosols by coughing.

High-flow Tracheal Oxygenation with Airway Exchange Catheter: A Novel Approach.

How to cite this article: Vaithialingam B, Arun BG. High-flow Tracheal Oxygenation with Airway Exchange Catheter: A Novel Approach. Indian J Crit Care Med 2023;27(6):456.

Limitations of the ARDS criteria during high-flow oxygen or non-invasive ventilation: evidence from critically ill COVID-19 patients.

BACKGROUND: The ratio of partial pressure of arterial oxygen to inspired oxygen fraction (PaO2/FIO2) during invasive mechanical ventilation (MV) is used as criteria to grade the severity of respiratory failure in acute respiratory distress syndrome (ARDS). During the SARS-CoV2 pandemic, the use of PaO2/FIO2 ratio has been increasingly used in non-invasive respiratory support such as high-flow nasal cannula (HFNC) and non-invasive ventilation (NIV). The grading of hypoxemia in non-invasively ventilated patients is uncertain. The main hypothesis, investigated in this study, was that the PaO2/FIO2 ratio does not change when switching between MV, NIV and HFNC. METHODS: We investigated respiratory function in critically ill patients with COVID-19 included in a single-center prospective observational study of patients admitted to the intensive care unit (ICU) at Uppsala University Hospital in Sweden. In a steady state condition, the PaO2/FIO2 ratio was recorded before and after any change between two of the studied respiratory support techniques (i.e., HFNC, NIV and MV). RESULTS: A total of 148 patients were included in the present analysis. We find that any change in respiratory support from or to HFNC caused a significant change in PaO2/FIO2 ratio. Changes in respiratory support between NIV and MV did not show consistent change in PaO2/FIO2 ratio. In patients classified as mild to moderate ARDS during MV, the change from HFNC to MV showed a variable increase in PaO2/FIO2 ratio ranging between 52 and 140 mmHg (median of 127 mmHg). This made prediction of ARDS severity during MV from the apparent ARDS grade during HFNC impossible. CONCLUSIONS: HFNC is associated with lower PaO2/FIO2 ratio than either NIV or MV in the same patient, while NIV and MV provided similar PaO2/FIO2 and thus ARDS grade by Berlin definition. The large variation of PaO2/FIO2 ratio indicates that great caution should be used when estimating ARDS grade as a measure of pulmonary damage during HFNC.

Effect of high-flow oxygen versus T-piece ventilation strategies during spontaneous breathing trials on weaning failure among patients receiving mechanical ventilation: a randomized controlled trial.

BACKGROUND: A spontaneous breathing trial (SBT) is used to determine whether patients are ready for extubation, but the best method for choosing the SBT strategy remains controversial. We investigated the effect of high-flow oxygen versus T-piece ventilation strategies during SBT on rates of weaning failure among patients receiving mechanical ventilation. METHODS: This randomized clinical trial was conducted from June 2019 through January 2022 among patients receiving mechanical ventilation for ≥ 12 h who fulfilled the weaning readiness criteria at a single-center medical intensive care unit. Patients were randomized to undergo either T-piece SBT or high-flow oxygen SBT. The primary outcome was weaning failure on day 2, and the secondary outcomes were weaning failure on day 7, ICU and hospital length of stay, and ICU and in-hospital morality. RESULTS: Of 108 patients (mean age, 67.0 ± 11.1 years; 64.8% men), 54 received T-piece SBT and 54 received high-flow oxygen SBT. Weaning failure on day 2 occurred in 5 patients (9.3%) in the T-piece group and 3 patients (5.6%) in the high-flow group (difference, 3.7% [95% CI, - 6.1-13.6]; p = 0.713). Weaning failure on day 7 occurred in 13 patients (24.1%) in the T-piece group and 7 patients (13.0%) in the high-flow group (difference, 11.1% [95% CI, - 3.4-25.6]; p = 0.215). A post hoc subgroup analysis showed that high-flow oxygen SBT was significantly associated with a lower rate of weaning failure on day 7 (OR, 0.17 [95% CI, 0.04-0.78]) among those patients intubated because of respiratory failure (p for interaction = 0.020). The ICU and hospital length of stay and mortality rates did not differ significantly between the two groups. During the study, no serious adverse events were recorded. CONCLUSIONS: Among patients receiving mechanical ventilation, high-flow oxygen SBT did not significantly reduce the risk of weaning failure compared with T-piece SBT. However, the study may have been underpowered to detect a clinically important treatment effect for the comparison of high-flow oxygen SBT versus T-piece SBT, and a higher percentage of patients with simple weaning and a lower weaning failure rate than expected should be considered when interpreting the findings. Clinical trial registration This trial was registered with ClinicalTrials.gov (number NCT03929328) on April 26, 2019.

A rare combination of methemoglobinemia and carboxyhemoglobinemia in pesticide poisoning.

Dyshemoglobinemias are disorders in which the haemoglobin is functionally altered and prevented from carrying oxygen. They include carboxyhemoglobin, methemoglobin, and sulfhemoglobin. This increase in abnormal haemoglobin has reduced oxygen binding capacity, which leads to decrease in total oxygen content in the blood causing anaemic-hypoxia. The anaemic-hypoxia which is present in these disorders are refractory to the oxygen supplementation and cause many systemic and life threatening complications.Many cases are reported in literature with either of haemoglobin. It is very rare to have two abnormal haemoglobin levels in the same patient. Here we discuss an uncommon case which presented to our tertiary care hospital after consuming pesticide with suicidal intention. The patient was very pale, had peripheral cyanosis,tachypnea and tachycardia and dizziness on presentation. The SpO2 of 85% was our clue to suspect methemoglobinemia which was confirmed along with carboxyhemoglobinemia on arterial blood gas saving result. Despite that patient being very unstable, she was successfully managed with 100% oxygen through High flow nasal cannula (HFNC), methylene blue and blood transfusion. The patient's signs and symptoms gradually reduced in a few days and got discharged after 2 weeks without any neurological and cardiorespiratory sequelae. An early suspicion and personalized emergency management was the key to success. As in all fields of Medicine, Emergency Medicine is also witnessing a change towards precision and personalized Medicine practice.

High-flow nasal oxygen as first-line therapy for COVID-19-associated hypoxemic respiratory failure: a single-centre historical cohort study.

PURPOSE: The optimal noninvasive modality for oxygenation support in COVID-19-associated hypoxemic respiratory failure and its association with healthcare worker infection remain uncertain. We report here our experience using high-flow nasal oxygen (HFNO) as the primary support mode for patients with COVID-19 in our institution. METHODS: We conducted a single-centre historical cohort study of all COVID-19 patients treated with HFNO for at least two hours in our university-affiliated and intensivist-staffed intensive care unit (Jewish General Hospital, Montreal, QC, Canada) between 27 August 2020 and 30 April 2021. We report their clinical characteristics and outcomes. Healthcare workers in our unit cared for these patients in single negative pressure rooms wearing KN95 or fit-tested N95 masks; they underwent mandatory symptomatic screening for COVID-19 infection, as well as a period of asymptomatic screening. RESULTS: One hundred and forty-two patients were analysed, with a median [interquartile range (IQR)] age of 66 [59-73] yr; 71% were male. Patients had a median [IQR] Sequential Organ Failure Assessment Score of 3 [2-3], median [IQR] oxygen saturation by pulse oximetry/fraction of inspired oxygen ratio of 120 [94-164], and a median [IQR] 4C score (a COVID-19-specific mortality score) of 12 [10-14]. Endotracheal intubation occurred in 48/142 (34%) patients, and overall hospital mortality was 16%. Barotrauma occurred in 21/142 (15%) patients. Among 27 symptomatic and 139 asymptomatic screening tests, there were no cases of HFNO-related COVID-19 transmission to healthcare workers. CONCLUSION: Our experience indicates that HFNO is an effective first-line therapy for hypoxemic respiratory failure in COVID-19 patients, and can be safely used without significant discernable infection risk to healthcare workers.

RéSUMé: OBJECTIF: La modalité non invasive optimale pour le soutien en oxygène lors d'insuffisance respiratoire hypoxémique liée à la COVID-19 et son association avec l'infection des travailleurs de la santé restent incertaines. Nous rapportons ici notre expérience avec l'utilisation de canules nasales à haut débit (CNHD) comme principale modalité de soutien pour les patients atteints de COVID-19 dans notre établissement. MéTHODE: Nous avons mené une étude de cohorte historique monocentrique de tous les patients atteints de COVID-19 traités par CNHD pendant au moins deux heures dans notre unité de soins intensifs affiliée à l'université et dotée d'intensivistes (Hôpital général juif, Montréal, QC, Canada) entre le 27 août 2020 et le 30 avril 2021. Nous rapportons leurs caractéristiques cliniques et leurs résultats. Les travailleurs de la santé de notre unité ont soigné ces patients dans des chambres individuelles à pression négative en portant des masques KN95 ou N95 ajustés; ils ont subi un dépistage symptomatique obligatoire de l'infection à la COVID-19, ainsi qu'un dépistage en période asymptomatique. RéSULTATS: Cent quarante-deux patients ont été analysés, avec un âge médian [écart interquartile (ÉIQ)] de 66 [59-73] ans; 71 % étaient des hommes. Les patients avaient un score SOFA (Sequential Organ Failure Assessment) médian [ÉIQ] de 3 [2, 3], un ratio médian [ÉIQ] de saturation en oxygène par oxymétrie de pouls/fraction d'oxygène inspiré de 120 [94-164], et un score 4C (un score de mortalité spécifique à la COVID-19) médian [ÉIQ] de 12 [10­14]. Dans l'ensemble, 48/142 patients (34 %) ont reçu une intubation endotrachéale, et la mortalité hospitalière globale était de 16 %. Un barotraumatisme est survenu chez 21/142 (15 %) patients. Parmi les 27 tests de dépistage symptomatiques et 139 tests asymptomatiques, aucun cas de transmission de COVID-19 liée aux CNHD aux travailleurs de la santé n'a été observé. CONCLUSION: Notre expérience indique que les CNHD constituent un traitement de première intention efficace pour l'insuffisance respiratoire hypoxémique chez les patients atteints de COVID-19 qui peut être utilisé en toute sécurité, sans risque d'infection significatif discernable pour les travailleurs de la santé.

Systematic review and meta-analysis of efficacy and safety of continuous positive airways pressure versus high flow oxygen cannula in acute bronchiolitis.

INTRODUCTION: There are a trend towards increasing use of High-Flow Nasal Cannula (HFNC), outside of paediatric intensive care unit. Give this trend is necessary to update the actual evidence and to assess available published literature to determinate the efficacy of HFNC over Continuous Positive Air Pressure (CPAP) as treatment for children with severe bronchiolitis. METHODS: We searched MEDLINE, EMBASE, LILACS, and COCHRANE Central, and gray literature in clinical trials databases ( www. CLINICALTRIALS: gov ), from inception to June 2022. The inclusion criteria for the literature were randomized clinical trials (RCTs) that included children < 2 years old, with acute moderate or severe bronchiolitis. All study selection and data extractions are performed independently by two reviewers. RESULTS: The initial searches including 106 records. Only five randomized controlled trial that met the inclusion criteria were included in meta-analysis. The risk of invasive mechanical ventilation was not significantly different in CPAP group and HFNC group [OR: 1.18, 95% CI (0.74, 1.89), I² = 0%] (very low quality). The risk of treatment failure was less significantly in CPAP group than HFNC group [OR: 0.51, 95% CI (0.36, 0.75), I² = 0%] (very low quality). CONCLUSION: In conclusion, there was no significant difference between HFNC and CPAP in terms of risk of invasive mechanical ventilation. CPAP reduces de risk of therapeutic failure with a highest risk of non severe adverse events. More trials are needed to confirm theses results.

Application of high-flow oxygen therapy in acute pancreatitis complicated with acute respiratory dysfunction.

BACKGROUND: To reveal the potential efficiency of high-flow oxygen therapy in acute pancreatitis complicated with acute respiratory dysfunction compared with conventional oxygen therapy. METHODS: We retrospectively analyzed 69 patients treated with high-flow oxygen or conventional oxygen therapy, then compared the difference of prime and second outcomes between the two groups. RESULTS: The high-flow oxygen group had lower intubation rate (25.6% vs. 56.7%, p = 0.013) and longer median time to intubation (64.25 h vs. 7.75 h, p < 0.001) compared with the conventional oxygen group. High-flow oxygen had a stronger effect on improving dyspnea (87.2% vs. 56.7%, p = 0.006) and regression of respiratory failure (66.7% vs. 26.7%, p = 0.001). In the univariate and multivariate analyses, high-flow oxygen and APACHE II score were independent predict factors to respiratory failure regression (OR = 20.381, p = 0.038; OR = 36.827, p = 0.026). Patients treated with high-flow oxygen had shorter intensive care unit stay length (19.5 ± 13.4 vs. 7.8 ± 4.7, p = 0.009) and early mortality tended to be significantly lower (17.9% vs. 40.0%, p = 0.058). DISCUSSION: High-flow oxygen is a more effective method for acute pancreatitis complicated with acute respiratory dysfunction than conventional oxygen therapy.

The efficacy of high-flow oxygen versus conventional oxygen for asthma control: a meta-analysis of randomized controlled studies.

Introduction: The efficacy of high-flow oxygen versus conventional oxygen therapy for asthma control remains controversial. Aim: This meta-analysis aims to explore the influence of high-flow oxygen versus conventional oxygen therapy on asthma control. Material and methods: We have searched PubMed, Embase, Web of Science, EBSCO, and Cochrane library databases, and included randomized controlled trials (RCTs) assessing the efficacy of high-flow oxygen versus conventional oxygen therapy for asthma control. Results: Four RCTs are included in this meta-analysis. Overall, compared with conventional oxygen therapy for asthma, high-flow oxygen is associated with a significantly lower dyspnoea score (standard mean difference (SMD) = -0.63; 95% confidence interval (CI): -1.08 to -0.17; p = 0.008), but reveals no remarkable influence on PaCO2 (SMD = 0.28; 95% CI: -0.22 to 0.77; p = 0.28), PaO2 (SMD = 0.44; 95% CI: -1.34 to 2.22; p = 0.63), intubation rate (OR = 1.09; 95% CI: 0.15 to 8.21; p = 0.93) or hospital length of stay (SMD = -0.07; 95% CI: -0.41 to 0.27; p = 0.67). Conclusions: High-flow oxygen may benefit to reduce/may be more beneficial in reducing the dyspnoea score than conventional oxygen therapy for asthma, but shows no improvement in PaCO2, PaO2, intubation or hospital length of stay.

Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort.

BACKGROUND: Uncertainty about the optimal respiratory support strategies in critically ill COVID-19 patients is widespread. While the risks and benefits of noninvasive techniques versus early invasive mechanical ventilation (IMV) are intensely debated, actual evidence is lacking. We sought to assess the risks and benefits of different respiratory support strategies, employed in intensive care units during the first months of the COVID-19 pandemic on intubation and intensive care unit (ICU) mortality rates. METHODS: Subanalysis of a prospective, multinational registry of critically ill COVID-19 patients. Patients were subclassified into standard oxygen therapy ≥10 L/min (SOT), high-flow oxygen therapy (HFNC), noninvasive positive-pressure ventilation (NIV), and early IMV, according to the respiratory support strategy employed at the day of admission to ICU. Propensity score matching was performed to ensure comparability between groups. RESULTS: Initially, 1421 patients were assessed for possible study inclusion. Of these, 351 patients (85 SOT, 87 HFNC, 87 NIV, and 92 IMV) remained eligible for full analysis after propensity score matching. 55% of patients initially receiving noninvasive respiratory support required IMV. The intubation rate was lower in patients initially ventilated with HFNC and NIV compared to those who received SOT (SOT: 64%, HFNC: 52%, NIV: 49%, p = 0.025). Compared to the other respiratory support strategies, NIV was associated with a higher overall ICU mortality (SOT: 18%, HFNC: 20%, NIV: 37%, IMV: 25%, p = 0.016). CONCLUSION: In this cohort of critically ill patients with COVID-19, a trial of HFNC appeared to be the most balanced initial respiratory support strategy, given the reduced intubation rate and comparable ICU mortality rate. Nonetheless, considering the uncertainty and stress associated with the COVID-19 pandemic, SOT and early IMV represented safe initial respiratory support strategies. The presented findings, in agreement with classic ARDS literature, suggest that NIV should be avoided whenever possible due to the elevated ICU mortality risk.

Comparison of hypoxemia, intubation procedure, and complications for non-invasive ventilation against high-flow nasal cannula oxygen therapy for patients with acute hypoxemic respiratory failure: a non-randomized retrospective analysis for effectiveness and safety (NIVaHIC-aHRF).

BACKGROUND: Optimization of preoxygenation procedure can help to secure the method of intubation by reducing the risks of severe hypoxemia and other problems. There is confusion for efficacy of non-invasive ventilation compared to high-flow oxygen therapy regarding occurrence of severe hypoxemia during the intubation procedure. The purpose of the study was to compare the difference between noninvasive ventilation and high flow oxygen therapy to prevent desaturation during laryngoscopy. METHODS: Patients underwent high-flow nasal cannula oxygen therapy (HCO cohort, n = 161) or non-invasive ventilation procedure (NIV cohort, n = 154) for oxygenation and ventilation due to acute hypoxemic respiratory failure in the intensive care unit. Data before preoxygenation, preoxygenation, intubation, laryngoscopy, and complications of patients due to tracheal intubation were retrospectively collected and analyzed. RESULTS: There was no difference between both cohorts for the demographical and clinical conditions of the patients before preoxygenation (p > 0.05 for all parameters), numbers of patients with severe hypoxia during the intubation procedure (35 vs. 45, p = 0.303), the time duration of laryngoscopy (p = 0.847), number of laryngoscopies attempts (p = 0.804), and immediate and late complications during the intubation procedure. The values of pulse oximetry were reported higher for patients of NIV cohort than those of HCO cohort during preoxygenation. Fewer numbers of patients were reported with severe hypoxia among patients of the NIV cohort than those of the HCO cohort (24 vs., 40, p = 0.042) who have moderate-to-severe hypoxemia (partial pressure of arterial oxygen to fraction of inspired oxygen ratio ≤ 200 mmHg) before preoxygenation. The most common complications were hypertension, pulmonary aspiration, and increased 30-day mortality. CONCLUSIONS: When compared, there was no difference between non-invasive ventilation technique and high-flow oxygen therapy to minimize severe hypoxia prior to laryngoscopy and endotracheal intubation in patients with acute respiratory failure.

High-flow Oxygen Therapy via Tracheostomy to Liberate COVID-19-induced ARDS from Invasive Ventilation: A Case Series.

Lung involvement with differing phenotypes characterizes COVID-19-induced acute respiratory distress syndrome (CARDS). The liberation of these patients from mechanical ventilation has been challenging. Excessive stress and strain following increased respiratory efforts spiral their vulnerable lung tissue into ventilator-induced lung injury vortex. The use of high-flow oxygen therapy via tracheostomy (HFOTTracheal)eases weaning process. As a safe option for both the patient and the healthcare workers, HFOTTracheal was successfully employed to wean two CARDS patients from the mechanical ventilator. How to cite this article: Vadi S, Phadtare S, Shetty K. High-flow Oxygen Therapy via Tracheostomy to Liberate COVID-19-induced ARDS from Invasive Ventilation: A Case Series. Indian J Crit Care Med 2021;25(6):724-728.

Preventive use of respiratory support after scheduled extubation in critically ill medical patients-a network meta-analysis of randomized controlled trials.

BACKGROUND: Respiratory support has been increasingly used after extubation for the prevention of re-intubation and improvement of prognosis in critically ill medical patients. However, the optimal respiratory support method is still under debate. This network meta-analysis (NMA) aims to evaluate the comparative effectiveness of various respiratory support methods used for preventive purposes after scheduled extubation in critically ill medical patients. METHODS: A systematic database search was performed from inception to December 19, 2019, for randomized controlled trials (RCTs) that compared a preventive use of different respiratory support methods, including conventional oxygen therapy (COT), noninvasive ventilation (NIV), high-flow oxygen therapy (HFOT), and combinational use of HFOT and NIV (HFOT+NIV), after planned extubation in adult critically ill medical patients. Study selection, data extraction, and quality assessments were performed in duplicate. The primary outcomes included re-intubation rate and short-term mortality. RESULTS: Seventeen RCTs comprising 3341 participants with 4 comparisons were included. Compared with COT, NIV significantly reduced the re-intubation rate [risk ratio (RR) 0.55, 95% confidence interval (CI) 0.39 to 0.77; moderate quality of evidence] and short-term mortality (RR 0.66, 95% CI 0.48 to 0.91; moderate quality of evidence). Compared to COT, HFOT had a beneficial effect on the re-intubation rate (RR 0.55, 95% CI 0.35 to 0.86; moderate quality of evidence) but no effect on short-term mortality (RR 0.79, 95% CI 0.56 to 1.12; low quality of evidence). No significant difference in the re-intubation rate or short-term mortality was found among NIV, HFOT, and HFOT+NIV. The treatment rankings based on the surface under the cumulative ranking curve (SUCRA) from best to worst for re-intubation rate were HFOT+NIV (95.1%), NIV (53.4%), HFOT (51.2%), and COT (0.3%), and the rankings for short-term mortality were NIV (91.0%), HFOT (54.3%), HFOT+NIV (43.7%), and COT (11.1%). Sensitivity analyses of trials with a high risk of extubation failure for the primary outcomes indicated that the SUCRA rankings were comparable to those of the primary analysis. CONCLUSIONS: After scheduled extubation, the preventive use of NIV is probably the most effective respiratory support method for comprehensively preventing re-intubation and short-term death in critically ill medical patients, especially those with a high risk of extubation failure.

High-Flow Oxygen Therapy Concepts: Time to Standardize Nomenclature and Avoid Confusion.

High-flow nasal oxygen systems are rapidly being adopted as an initial noninvasive treatment for acute respiratory failure. However, the term "high-flow nasal cannula" is nonspecific and leads to imprecise communication between physicians, respiratory therapists, and nurses with the potential for patient harm. In this viewpoint and a brief review of the technology, we argue for a change in nomenclature in order to reduce the chance for future clinical, administrative, and research misunderstanding surrounding high-flow nasal oxygen systems.

The Effect of High-Flow Nasal Oxygen Therapy on Postoperative Pulmonary Complications and Hospital Length of Stay in Postoperative Patients: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the effect of high-flow nasal cannula oxygen (HFNO) therapy on hospital length of stay (LOS) and postoperative pulmonary complications (PPCs) in adult postoperative patients. DATA SOURCES: PubMed, Embase, the Cochrane Library, Web of Science of Studies, China National Knowledge Index, and Wan Fang databases were searched until July 2018. STUDY SELECTION: Randomized controlled trials (RCTs) comparing HFNO with conventional oxygen therapy or noninvasive mechanical ventilation in adult postoperative patients were included. The primary outcomes were hospital LOS and PPCs; short-term mortality (defined as intensive care unit, hospital, or 28-day mortality) and intubation rate were the secondary outcomes. DATA EXTRACTION: Demographic variables, high-flow oxygen therapy application, effects, and side effects were retrieved. Data were analyzed by the methods recommended by the Cochrane Collaboration. The strength of evidence was assessed by the Grading of Recommendations Assessment, Development and Evaluation. Random errors were evaluated with trial sequential analysis. DATA SYNTHESIS: Fourteen studies (2568 patients) met the inclusion criteria and were included. Compared to the control group, the pooled effect showed that HFNO was significantly associated with a shorter hospital stay (mean difference: -0.81; 95% confidence interval [CI]: -1.34 to -0.29, P = .002), but not mortality (risk ratio [RR]: 1.0, 95% CI: 0.63 to 1.59, P = 1.0). Weak evidence of a reduction in reintubation rate (RR: 0.76, 95% CI: 0.57-1.01, P = .06) and PPC rate (RR: 0.89, 95% CI: 0.75-1.06, P = .18) with HFNO versus control group was recorded. CONCLUSIONS: The available RCTs suggest that, among the adult postoperative patients, HFNO therapy compared to the control group significantly reduces hospital LOS.

High-flow oxygen and pro-serotonin agents for non-interventional treatment of post-dural-puncture headache.

OBJECTIVE: Post dural puncture headache (PDPH) is a common complication in patients following diagnostic or therapeutic lumbar puncture, procedures requiring epidural access, and spinal surgery. Epidural blood patch (EBP), the gold standard for the treatment of this pathology requires training not provided to emergency physicians. In addition, the presence of concomitant pathology and abnormal laboratory values are contraindications to perform EBP. In presence of these limitations, we sought for a non-interventional management of PDPH utilizing high-flow oxygen and pro-serotonin agents. We reviewed the mechanism of action of this therapy METHODS: To illustrate our proposal, we report a series of twelve consecutive patients with PDPH treated with high-flow oxygen therapy at 12 L/min via a non-rebreathing mask and intravenous metoclopramide. RESULTS: All patients were treated with this conservative therapy, no adverse reactions were observed. After the intervention, the headache resolved without further indications for PDPH. CONCLUSION: Our series suggests that combining high-flow oxygen and pro-serotonin agents such metoclopramide in the ED might be a feasible option as effective as the invasive methods used in treating PDPH. This therapy appears to be efficient and to minimize risk, cost and side effects. It presents an easily accessible alternative that should be considered when PDPH is not a viable option.