The use of oxygen hoods in patients failing on conventional high-flow oxygen delivery systems, the effects on oxygenation, mechanical ventilation and mortality rates in hypoxic patients with COVID-19. A Prospective Controlled Cohort Study

Introduction: The use of high-flow nasal cannulas (HFNC) in patients with hypoxemic ventilatory failure reduces the need for mechanical ventilation and does not increase mortality when intubation is promptly applied. The aim of the study is to describe the behavior of HFNC in patients who live at high altitudes, and the performance of predictors of success/failure of this strategy. Methods: Prospective multicenter cohort study, with patients aged over 18 years recruited for 12 months in 2020 to 21. All had a diagnosis of hypoxemic respiratory failure secondary to pneumonia, were admitted to intensive care units, and were receiving initial management with a high-flow nasal cannula. The variables assessed included need for intubation, mortality in ICU, and the validation of SaO2, respiratory rate (RR) and ROX index (IROX) as predictors of HFNC success / failure. Results: One hundred and six patients were recruited, with a mean age of 59 years and a success rate of 74.5%. Patients with treatment failure were more likely to be obese (BMI 27.2 vs 25.5; OR: 1.03; 95% CI: .95-1.1) and had higher severity scores at admission (APACHE II 12 vs 20; OR 1.15; 95% CI: 1.06-1.24). Respiratory rates after 12 (AUC .81 CI: .70-.92) and 18 h (AUC .85 CI: .72-0.90) of HFNC use were the best predictors of failure, performing better than those that included oxygenation. ICU mortality was higher in the failure group (6% vs 29%; OR 8.8; 95% CI:1.75-44.7). Conclusions: High-flow oxygen cannula therapy in patients with hypoxemic respiratory failure living at altitudes above 2600 m is associated with low rates of therapy failure and a reduced need for mechanical ventilation in the ICU. The geographical conditions and secondary physiological changes influence the performance of the traditionally validated predictors of therapy success. Respiratory rate <30 proved to be the best indicator of early success of the device at 12 h of use.

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Randomised controlled trial to assess the effectiveness of apnoeic oxygenation in adults using low-flow or high-flow nasal cannula with head side elevation versus usual care to prevent desaturation during endotracheal intubation in the emergency department (ApOxED): study protocol

BMJ Open ◽

10.1136/bmjopen-2020-037964 ◽

2020 ◽

Vol 10 (11) ◽

pp. e037964

Author(s):

Shahan Waheed ◽

Nazir Najeeb Kapadia ◽

Muhammad Faisal Khan ◽

Salima Mansoor Kerai ◽

Ahmed Raheem ◽

...

Keyword(s):

Endotracheal Intubation ◽

Direct Laryngoscopy ◽

Oxygen Delivery ◽

High Flow ◽

Nasal Cannula ◽

Low Flow ◽

Usual Practice ◽

High Flow Oxygen ◽

Randomised Controlled ◽

Apnoeic Oxygenation

IntroductionApnoeic oxygenation is a process of delivering continuous oxygen through nasal cannula during direct laryngoscopy. The oxygen that is delivered through these nasal cannulas is either low flow or high flow. Although the effectiveness of apnoeic oxygenation has been shown through systematic reviews and randomised controlled trials, a comparison of high-flow versus low-flow oxygen delivery has not been tested through a superiority study design. In this study we propose to assess the effectiveness of giving low-flow oxygen with head side elevation versus high-flow oxygen with head side elevation against the usual practice of care in which no oxygen is provided during direct laryngoscopy.Methods and analysisThis will be a three-arm study instituting a block randomisation technique with a sample size of 46 in each arm (see table 1). Due to the nature of the intervention, no blinding will be introduced. The primary outcomes will be lowest non-invasive oxygen saturation measurement during direct laryngoscopy and during the 2 min after the placement of the tube and the first pass success rate. The intervention constitutes head side elevation up to 30° for improving glottis visualisation together with low-flow or high-flow oxygen delivery through nasal cannula to increase safe apnoea time for participants undergoing endotracheal intubation. Primary analysis will be intention to treat.Ethics and disseminationThe study is approved by the Ethical Review Committee of Aga Khan University Hospital (2019-0726-2463). The project is an institution University Research Committee grant recipient 192 002ER-PK. The results of the study will be disseminated among participants, patient communities and healthcare professionals in the institution through seminars, presentations and emails. Further, the findings will be published in a highly accessed peer-reviewed medical journal and will be presented at both national and international conferences.Trial registration numberClinicalTrials.gov Registry (NCT04242537).

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High-flow oxygen via tracheostomy improves oxygenation in patients weaning from mechanical ventilation: a randomised crossover study

Intensive Care Medicine ◽

10.1007/s00134-016-4634-7 ◽

2016 ◽

Vol 43 (3) ◽

pp. 465-467 ◽

Cited By ~ 10

Author(s):

Amanda Corley ◽

Melannie Edwards ◽

Amy J. Spooner ◽

Kimble R. Dunster ◽

Chris Anstey ◽

...

Keyword(s):

Mechanical Ventilation ◽

Crossover Study ◽

High Flow ◽

Weaning From Mechanical Ventilation ◽

High Flow Oxygen

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Effect of Low Flow and High Flow Oxygen Delivery on Exercise Tolerance and Sensation of Dyspnea

CHEST Journal ◽

10.1378/chest.105.4.1061 ◽

1994 ◽

Vol 105 (4) ◽

pp. 1061-1065 ◽

Cited By ~ 58

Author(s):

Naresh A. Dewan ◽

C. William Bell

Keyword(s):

Oxygen Delivery ◽

Exercise Tolerance ◽

High Flow ◽

Low Flow ◽

High Flow Oxygen

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What Are High-Flow and Low-Flow Oxygen Delivery Systems?

Stroke ◽

10.1161/01.str.0000185387.51425.f9 ◽

2005 ◽

Vol 36 (10) ◽

pp. 2066-2067 ◽

Cited By ~ 7

Author(s):

Ritesh Agarwal ◽

Dheeraj Gupta

Keyword(s):

Oxygen Delivery ◽

Delivery Systems ◽

High Flow ◽

Low Flow

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Point-of-care lung ultrasound predicts severe disease and death due to COVID-19: a prospective cohort study.

10.1101/2021.12.30.21268558 ◽

2022 ◽

Author(s):

Paul W Blair ◽

Trishul Siddharthan ◽

Gigi Liu ◽

Jiawei Bai ◽

Joshua East ◽

...

Keyword(s):

Cohort Study ◽

Disease Progression ◽

Prospective Cohort Study ◽

Prospective Cohort ◽

Lung Ultrasound ◽

Point Of Care ◽

Tertiary Care ◽

High Flow ◽

Pleural Line ◽

High Flow Oxygen

Objective: The clinical utility of point-of-care lung ultrasound (LUS) for disease severity triage of hospitalized patients with COVID-19 is unclear. Design: Prospective cohort study Setting: A large tertiary care center in Maryland, USA between April 2020 to September 2021. Patients: Hospitalized adults (18 years of age or greater) with positive SARS-CoV-2 RT-PCR results. Interventions: None. Measurements and Main Results: All patients were scanned using a standardized protocol including 12 lung zones and followed to determine clinical outcomes until hospital discharge and vital status at 28-days. Ultrasounds were independently reviewed for lung and pleural line artifacts and abnormalities, and the mean Lung Ultrasound Score (ranging from 0 to 3) across lung zones (mLUSS) was determined. The primary outcome was time to ICU-level care, defined as high flow oxygen, noninvasive, or mechanical ventilation, within 28-days of the initial ultrasound. Cox proportional hazards regression models adjusted for age and sex were fit for mLUSS and each ultrasound covariate. A total of 264 participants were enrolled in the study; the median age was 59 years and 114 (43.2) % of participants were female. The median mLUSS was 1 (interquartile range: 0.5 to 1.3). Following enrollment, 29 (11.0%) participants went on to require ICU-level care and 14 (5.3%) subsequently died by 28 days. Each increase in mLUSS at enrollment was associated with disease progression to ICU-level care (aHR = 3.63; 95% CI: 1.23 to 10.65) and 28-day mortality (aHR = 4.50; 95% CI: 1.52 to 13.31). Pleural line abnormalities were independently associated with disease progression to ICU-level care (aHR = 18.86; CI: 1.57 to 226.09). Conclusions: Participants with a mLUSS of 1 or more or pleural line changes on LUS had an increased likelihood of subsequent requirement of high flow oxygen or greater. LUS is a promising tool for assessing risk of COVID-19 progression at the bedside.

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Safety and clinical outcomes of remdesivir in hospitalised COVID-19 patients: a retrospective analysis of active surveillance database

BMC Infectious Diseases ◽

10.1186/s12879-021-07004-8 ◽

2022 ◽

Vol 22 (1) ◽

Author(s):

Vaishali Gupte ◽

Rashmi Hegde ◽

Sandesh Sawant ◽

Kabil Kalathingal ◽

Sonali Jadhav ◽

...

Keyword(s):

Mechanical Ventilation ◽

Retrospective Analysis ◽

Clinical Outcomes ◽

Oxygen Therapy ◽

High Flow ◽

Low Flow ◽

Invasive Ventilation ◽

Non Invasive ◽

Non Invasive Ventilation ◽

High Flow Oxygen

Abstract Background Real-world data on safety and clinical outcomes of remdesivir in COVID-19 management is scant. We present findings of data analysis conducted for assessing the safety and clinical outcomes of remdesivir treatment for COVID-19 in India. Methods This retrospective analysis used data from an active surveillance programme database of hospitalised patients with COVID-19 who were receiving remdesivir. Results Of the 2329 patients included, 67.40% were men. Diabetes (29.69%) and hypertension (20.33%) were the most common comorbidities. At remdesivir initiation, 2272 (97.55%) patients were receiving oxygen therapy. Remdesivir was administered for 5 days in 65.38% of patients. Antibiotics (64.90%) and steroids (47.90%) were the most common concomitant medications. Remdesivir was overall well tolerated, and total 119 adverse events were reported; most common were nausea and vomiting in 45.40% and increased liver enzymes in 14.28% patients. 84% of patients were cured/improved, 6.77% died and 9.16% showed no improvement in their clinical status at data collection. Subgroup analyses showed that the mortality rate was significantly lower in patients < 60 years old than in those > 60 years old. Amongst patients on oxygen therapy, the cure/improvement rate was significantly higher in those receiving standard low-flow oxygen than in those receiving mechanical ventilation, non-invasive ventilation, or high-flow oxygen. Factors that were associated with higher mortality were age > 60 years, cardiac disease, diabetes high flow oxygen, non-invasive ventilation and mechanical ventilation. Conclusion Our analysis showed that remdesivir is well tolerated and has an acceptable safety profile. The clinical outcome of cure/improvement was 84%, with a higher improvement in patients < 60 years old and on standard low-flow oxygen.

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Effects of high-flow oxygen therapy on patients with hypoxemia after extubation and predictors of reintubation: a retrospective study based on the MIMIC-IV database

BMC Pulmonary Medicine ◽

10.1186/s12890-021-01526-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Taotao Liu ◽

Qinyu Zhao ◽

Bin Du

Keyword(s):

Mechanical Ventilation ◽

Treatment Group ◽

Medical Information ◽

Characteristic Curve ◽

Oxygenation Index ◽

High Flow ◽

Control Group ◽

Severe Hypoxemia ◽

High Flow Oxygen ◽

Weaning Failure

Abstract Background To investigate the indications for high-flow nasal cannula oxygen (HFNC) therapy in patients with hypoxemia during ventilator weaning and to explore the predictors of reintubation when treatment fails. Methods Adult patients with hypoxemia weaning from mechanical ventilation were identified from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The patients were assigned to the treatment group or control group according to whether they were receiving HFNC or non-invasive ventilation (NIV) after extubation. The 28-day mortality and 28-day reintubation rates were compared between the two groups after Propensity score matching (PSM). The predictor for reintubation was formulated according to the risk factors with the XGBoost algorithm. The areas under the receiver operating characteristic curve (AUC) was calculated for reintubation prediction according to values at 4 h after extubation, which was compared with the ratio of SpO2/FiO2 to respiratory rate (ROX index). Results A total of 524,520 medical records were screened, and 801 patients with moderate or severe hypoxemia when undergoing mechanical ventilation weaning were included (100 < PaO2/FiO2 ≤ 300 mmHg), including 358 patients who received HFNC therapy after extubation in the treatment group. There were 315 patients with severe hypoxemia (100 < PaO2/FiO2 ≤ 200 mmHg) before extubation, and 190 patients remained in the treatment group with median oxygenation index 166[157,180] mmHg after PSM. There were no significant differences in the 28-day reintubation rate or 28-day mortality between the two groups with moderate or severe hypoxemia (all P > 0.05). Then HR/SpO2 was formulated as a predictor for 48-h reintubation according to the important features predicting weaning failure. According to values at 4 h after extubation, the AUC of HR/SpO2 was 0.657, which was larger than that of ROX index (0.583). When the HR/SpO2 reached 1.2 at 4 h after extubation, the specificity for 48-h reintubation prediction was 93%. Conclusions The treatment effect of HFNC therapy is not inferior to that of NIV, even on patients with oxygenation index from 160 to 180 mmHg when weaning from ventilator. HR/SpO2 is more early and accurate in predicting HFNC failure than ROX index.

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