Efficiency of different flows for apneic oxygenation when using high flow nasal oxygen application – a technical simulation

Abstract Background Preoxygenation and application of apneic oxygenation are standard to prevent patients from desaturation e.g. during emergency intubation. The time before desaturation occurs can be prolonged by applying high flow oxygen into the airway. Aim of this study was to scientifically assess the flow that is necessary to avoid nitrogen entering the airway of a manikin model during application of pure oxygen via high flow nasal oxygen. Methods We measured oxygen content over a 20-min observation period for each method in a preoxygenated test lung applied to a human manikin, allowing either room air entering the airway in control group, or applying pure oxygen via high flow nasal oxygen at flows of 10, 20, 40, 60 and 80 L/min via nasal cannula in the other groups. Our formal hypothesis was that there would be no difference in oxygen fraction decrease between the groups. Results Oxygen content in the test lung dropped from 97 ± 1% at baseline in all groups to 43 ± 1% in the control group (p < 0.001 compared to all other groups), to 92 ± 1% in the 10 L/min group, 92 ± 1% in the 20 L/min group, 90 ± 1% in the 40 L/min group, 89 ± 0% in the 60 L/min group and 87 ± 0% in the 80 L/min group. Apart from comparisons 10 l/ min vs. 20 L/min group (p = .715) and 10/L/min vs. 40 L/min group (p = .018), p was < 0.009 for all other comparisons. Conclusions Simulating apneic oxygenation in a preoxygenated manikin connected to a test lung over 20 min by applying high flow nasal oxygen resulted in the highest oxygen content at a flow of 10 L/min; higher flows resulted in slightly decreased oxygen percentages in the test lung.

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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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Renal response to vasopressin and indomethacin in cisplatin-treated rats

Clinical Science ◽

10.1042/cs0730377 ◽

1987 ◽

Vol 73 (4) ◽

pp. 377-381 ◽

Cited By ~ 3

Author(s):

Christopher J. Lote ◽

Ernest S. Harpur ◽

Andrew Thewles ◽

Donna J. Phipps

Keyword(s):

Body Weight ◽

Single Dose ◽

Treated Group ◽

Urine Flow ◽

The Other ◽

Control Group ◽

Fischer 344 ◽

Antidiuretic Effect ◽

Natriuretic Effect ◽

Observation Period

1. Cisplatin [6 mg/kg body weight, in 0.9% (w/v) NaCl] was injected intraperitoneally as a single dose to two groups of rats (Fischer 344 strain). Two further groups of rats, injected intraperitoneally with an equivalent volume of 0.9% (w/v) NaCl, were used as controls. The cisplatin-treated rats developed a pronounced polyuria which did not recover during an 18 week observation period. 2. After 21 weeks, one group of the cisplatin-treated animals received a 6 h infusion of 2.5% d-glucose. Vasopressin (60 μ-units min−1 100 g−1 body weight) was incorporated into the infusate for the final 2 h. A control group of animals received an identical infusion. One week later the other group of cisplatin-treated rats received a 6 h infusion of 0.9% (w/v) NaCl. Indomethacin was incorporated into the infusate for 15 min, at 3 h 52.5 min, to deliver a dose of 10 mg/kg body weight. A control group again received an identical infusion. 3. Cisplatin did not impair the antidiuretic effect of vasopressin, but it reduced the natriuretic effect of vasopressin, and also impaired the ability of the animals to produce concentrated urine. 4. Cisplatin did not alter basal PGE2 excretion, or the reduction in PGE2 excretion induced by indomethacin. However, the urine flow in the cisplatin-treated group did not fall after indomethacin, whereas there was a fall in urine flow in the control group.

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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

10.21203/rs.3.rs-133541/v1 ◽

2020 ◽

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 Purpose 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 hours after extubation, which was compared with the ratio of SpO2/FiO2 to respiratory rate (ROX index). Results A total of 524520 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-hour reintubation according to the important features predicting weaning failure. According to values at 4 hours 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 hours after extubation, the specificity for 48-hour 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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Non‐invasive ventilation or high‐flow oxygen therapy: When to choose one over the other?

Respirology ◽

10.1111/resp.13435 ◽

2018 ◽

Vol 24 (8) ◽

pp. 724-731 ◽

Cited By ~ 6

Author(s):

Jean‐Pierre Frat ◽

Rémi Coudroy ◽

Arnaud W. Thille

Keyword(s):

Oxygen Therapy ◽

High Flow ◽

The Other ◽

Invasive Ventilation ◽

Non Invasive ◽

Non Invasive Ventilation ◽

High Flow Oxygen

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High Flow Oxygen Therapy in Patients with Burn Injury

Messenger of Anesthesiology and Resuscitation ◽

10.21292/2078-5658-2021-18-3-46-52 ◽

2021 ◽

Vol 18 (3) ◽

pp. 46-52

Author(s):

А. А. Ponomarev ◽

V. V. Kazennov ◽

А. N. Kudryavtsev ◽

А. V. Korneev ◽

А. А. Аlekseev

Keyword(s):

Respiratory Failure ◽

Oxygen Therapy ◽

Burn Injury ◽

Main Group ◽

High Flow ◽

Infusion Therapy ◽

Control Group ◽

Interstitial Pulmonary Edema ◽

High Flow Oxygen ◽

Respiratory Comfort

Some patients with severe burn injury have a high risk of developing acute respiratory failure, the cause of which may be interstitial pulmonary edema caused by inadequate infusion therapy.The objective: to evaluate the effectiveness of high-flow oxygen therapy (HFOT) in acute parenchymatous respiratory failure in burn patients.Subjects and methods. The prospective analysis included 74 patients with ARF in the stage of burn toxemia, without inhalation trauma, with PaO2/FiO2 below 300. In Main Group (37 patients), HFOT was used, while in Control Group patients received oxygenation through nasal cannula with the rate up to 15 l/min. Parameters of respiratory rate, PaO2/FiO2, PaCO2, MAP, heart rate, the number of intubations, respiratory comfort were recorded within 48 hours.Results. Main Group had higher values of oxygenation index in 48 hours of the trial (342 vs. 305.5, p = 0.02), faster normalization of blood gas composition compared to Control Group. HFOT was associated with greater respiratory comfort (8.4 vs. 5.3 VAS scores, p = 0.03), lower need in mechanical ventilation (4 vs. 11, p = 0.04).Conclusion: HFOT is an effective method for the treatment of respiratory failure in inpatients with burns. The need for intubation decreases, it is more comfortable to be tolerated than standard methods of oxygen therapy.

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Inhaled surfactant in patients with covid-19 who took high-flow oxygen: the results of a retrospective analysis

Medical Council ◽

10.21518/2079-701x-2020-17-75-80 ◽

2020 ◽

pp. 75-80

Author(s):

A. V. Averyanov ◽

T. V. Klypa ◽

O. I. Balionis ◽

M. V. Bychinin ◽

A. V. Cherniak ◽

...

Keyword(s):

Mechanical Ventilation ◽

Mortality Rate ◽

Retrospective Analysis ◽

Laboratory Data ◽

High Flow ◽

Inhalation Therapy ◽

Control Group ◽

Number Of Patients ◽

High Flow Oxygen ◽

Significant Difference

The article presents a comparative retrospective analysis of clinical, laboratory data and outcomes in 39 patients with severe COVID-19 complicated by acute respiratory distress syndrome, who received high-flow oxygen therapy. Of which, 19 patients additionally received 75 mg of inhaled surfactant BL twice daily for 5 days using a nebulizer. As a result, mortality rate in the group of patients receiving surfactant was 10.5%, while in the standard therapy group — 50%; the number of patients transferred to the mechanical ventilation was 21% and 70%, respectively. As the patients receiving the surfactant were injected with COVID-19 hyperimmune convalescent plasma and monoclonal antibodies to interleukin-6 receptors more often than those from the control group, we recalculated the results regardless of these patients. However, a significant difference between the mechanical ventilation rate (2.5 times less often in the surfactant group) and mortality rate (3.5 times less in the surfactant group) was observed. The duration of hospitalization and stay at the intensive care unit was not significantly different between patients with and without surfactant treatment. Inhalation therapy with surfactant BL was well tolerated even by patients with chronic obstructive pulmonary disease. In no case did therapy have to be stopped due to side effects, the most common of which was coughing during inhalation. This retrospective analysis shows that the prescription of an inhaled surfactant prior to transferring patients to mechanical ventilation can prevent the progression of respiratory failure, put down mechanical ventilation, and improve survival.

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High flow oxygen cannula: the other side of the moon

Intensive Care Medicine ◽

10.1007/s00134-015-3855-5 ◽

2015 ◽

Vol 41 (9) ◽

pp. 1673-1675 ◽

Cited By ~ 4

Author(s):

Alexandre Demoule ◽

Jordi Rello

Keyword(s):

High Flow ◽

The Other ◽

The Moon ◽

High Flow Oxygen

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Oxygenation laryngoscope vs. nasal standard and nasal high flow oxygenation in a technical simulation of apnoeic oxygenation

BMC Emergency Medicine ◽

10.1186/s12873-021-00407-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

H. Herff ◽

W. A. Wetsch ◽

S. Finke ◽

F. Dusse ◽

T. Mitterlechner ◽

...

Keyword(s):

Airway Management ◽

Oxygen Concentration ◽

High Flow ◽

Nasal Cannula ◽

Pure Oxygen ◽

High Flow Oxygen ◽

Failed Airway ◽

Oxygen Group ◽

And Control ◽

Apnoeic Oxygenation

Abstract Background Failed airway management is the major contributor for anaesthesia-related morbidity and mortality. Cannot-intubate-cannot-ventilate scenarios are the most critical emergency in airway management, and belong to the worst imaginable scenarios in an anaesthetist’s life. In such situations, apnoeic oxygenation might be useful to avoid hypoxaemia. Anaesthesia guidelines recommend careful preoxygenation and application of high flow oxygen in difficult intubation scenarios to prevent episodes of deoxygenation. In this study, we evaluated the decrease in oxygen concentration in a model when using different strategies of oxygenation: using a special oxygenation laryngoscope, nasal oxygen, nasal high flow oxygen, and control. Methods In this experimental study we compared no oxygen application as a control, standard pure oxygen application of 10 l·min− 1 via nasal cannula, high flow 90% oxygen application at 20 l·min− 1 using a special nasal high flow device, and pure oxygen application via our oxygenation laryngoscope at 10 l·min− 1. We preoxygenated a simulation lung to 97% oxygen concentration and connected this to the trachea of a manikin model simulating apnoeic oxygenation. Decrease in oxygen concentration in the simulation lung was measured continuously for 20 min. Results Oxygen concentration in the simulation lung dropped from 97 ± 1% at baseline to 40 ± 1% in the no oxygen group, to 80 ± 1% in the standard nasal oxygen group, and to 73 ± 2% in the high flow nasal oxygenation group. However, it remained at 96 ± 0% in the oxygenation laryngoscope group (p < 0.001 between all groups). Conclusions In this technical simulation, oxygenation via oxygenation laryngoscope was more effective than standard oxygen insufflation via nasal cannula, which was more effective than nasal high flow insufflation of 90% oxygen.

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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

Journal of Intensive Care Medicine ◽

10.1177/0885066618817718 ◽

2018 ◽

Vol 35 (10) ◽

pp. 1129-1140 ◽

Cited By ~ 2

Author(s):

Zhonghua Lu ◽

Wei Chang ◽

Shanshan Meng ◽

Ming Xue ◽

Jianfeng Xie ◽

...

Keyword(s):

Length Of Stay ◽

Oxygen Therapy ◽

Hospital Length ◽

Pulmonary Complications ◽

High Flow ◽

Hospital Length Of Stay ◽

Cochrane Library ◽

Control Group ◽

Postoperative Pulmonary Complications ◽

High Flow Oxygen

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.

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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

10.21203/rs.3.rs-133541/v2 ◽

2021 ◽

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 Purpose: 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 hours after extubation, which was compared with the ratio of SpO2/FiO2 to respiratory rate (ROX index).Results: A total of 524520 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-hour reintubation according to the important features predicting weaning failure. According to values at 4 hours 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 hours after extubation, the specificity for 48-hour 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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