Effect of high flow oxygen on exertional dyspnea in cancer patients: A double-blind randomized clinical trial.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 11600-11600
Author(s):  
David Hui ◽  
Liliana Larsson ◽  
Sajan Thomas ◽  
Carol Harrison ◽  
Jimin Wu ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Cancer Patients ◽  
Flow Rate ◽  
Mixed Effects ◽  
High Flow ◽  
Low Flow ◽  
Double Blind ◽  
Exertional Dyspnea ◽  
Exercise Time ◽  
High Flow Oxygen

11600 Background: High flow oxygen therapy is effective for hypoxemic respiratory failure. However, its effect on dyspnea in non-hypoxemic patients is unknown. In this 2x2 factorial, double-blind randomized clinical trial, we assessed the effect of flow rate (high vs. low) and gas (oxygen vs. air) on exertional dyspnea in cancer patients. Methods: Non-hypoxemic patients with cancer completed two structured cycle ergometer exercise tests with Low Flow Air [LFAir] at 2 L/min. They were then randomized to receive High Flow Oxygen [HFOx] with up to 60 L/min, High Flow Air [HFAir], Low Flow Oxygen [LFOx] or LFAir during a constant work rate exercise test at 80% maximum. Dyspnea intensity was assessed with the modified 0-10 Borg scale. The primary outcome was difference in the slope of dyspnea intensity vs. time during the third test. Secondary outcomes included difference in exercise time, vital signs, and adverse events. We estimated that 10 patients per arm will provide 86% power to detect a 1-standard deviation main effect and 86% power to detect a 2-SD interaction effect with an alpha of 5%. A linear mixed effects model was used to assess the impact of flow rate and gas on study outcomes. Results: 45 patients were randomized and 44 completed the study (10, 11, 12, 11 patients on HFOx, HFAir, LFOx, LFAir, respectively). The mean age was 63 (range 47-77); 18 (41%) were female; 34 (44%) had lung cancer; and 20 (46%) had metastatic disease. In mixed effects model, the association between the change in dyspnea intensity over time with flow rate differed significantly between oxygen and air (P = 0.04). Specifically, HFOx (slope difference -0.20, P < 0.001) and LFOx (-0.14, P = 0.01) were significantly better than LFAir, but not HFAir (+0.09, P = 0.09). Exercise time also significantly increased with HFOx (difference +2.5 min, P = 0.009) compared to LFAir, but not HFAir (+0.63 min, P = 0.48) or LFOx (+0.39 min, P = 0.65). HFOx was well tolerated without significant adverse effects. Conclusions: The combination of high flow rate and oxygen improved dyspnea and exercise duration during constant work exercise test in non-hypoxemic cancer patients. Larger trials are needed to confirm the benefits of HFOx during exercises. Clinical trial information: NCT02357134.

High flow oxygen for dyspnea in hospitalized patients with cancer: A 4x4 crossover randomized clinical trial.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 12077-12077
Author(s):  
David Hui ◽  
Farley Hernandez ◽  
Saji Thomas ◽  
Zhanni Lu ◽  
Ahmed F. Elsayem ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Cancer Patients ◽  
Mixed Model ◽  
High Flow ◽  
Hospitalized Patients ◽  
Low Flow ◽  
Borg Scale ◽  
Carryover Effect ◽  
Patients With Cancer ◽  
High Flow Oxygen

12077 Background: Dyspnea is common in hospitalized cancer patients and highly distressing. High flow oxygen (HFOx) is administered for oxygenation in this setting; however, its effect on dyspnea has not been well examined, particularly among non-hypoxemic patients. In this phase II trial, we assessed the effect of HFOx, high flow air (HFAir), low flow oxygen (LFOx) and low flow air (LFAir) on dyspnea. We hypothesized that HFO and HFA can alleviate dyspnea. Methods: This double-blind, 4x4 crossover clinical trial enrolled hospitalized patients with cancer who were dyspneic (NRS ≥3 at rest) and non-hypoxemic (SpO2>90% on room air). Patients were randomized to 10 minutes of HFOx, HFAir, LFOx and LFAir in different orders. The flow rate was titrated between 20-60 L/min in the high flow groups and 2 L/min in the low flow groups. The primary outcome was dyspnea 0-10 numeric rating scale (NRS) “now”, where 0=none and 10=worst. Secondary outcomes included modified Borg scale dyspnea intensity and unpleasantness, adverse effects, and overall preference. We compared among the interventions with a linear mixed model adjusting for time, treatment effect, period effect and carryover effect. Results: 17 patients completed 55 interventions in a random order. Mean age 51, 58% female, mean baseline dyspnea NRS 6.3 (SD 1.7). The absolute change of dyspnea NRS between 0 and 10 minutes was -1.8 (SD 1.7) for HFOx, -1.8 (2.0) for HFAir, -0.5 (0.8) for LFOx and -0.6 (1.2) for LFAir. In mixed model analysis, HFOx group provided greater dyspnea relief than LFOx (mean difference [95% CI] -0.80 [-1.45, -0.15], P=0.02) and LFAir (-1.24 [-1.90, -0.57], P<0.001). HFAir also provided a significantly greater dyspnea relief than LFOx (-0.95 [-1.61, -0.30], P=0.005) and LFAir (-1.39 [-2.05, -0.73], P<0.001). No difference was found between HFOx and HFAir nor between LFOx and LFAir. There was no significant carryover effect. Dyspnea Borg scale intensity and unpleasantness showed similar changes. Oxygen saturation increased in the HFOx group (97.2% to 99.7%) and LFOx group (95.5% to 98.2%) but not HFAir nor LFAir groups. HFOx was well tolerated. At the end of the study, 7 (54%), 4 (31%), 1 (8%) and 1 (8%) patients blindly preferred HFOx, HFAir, LFOx and LFAir, respectively. Conclusions: For the first time, we found that HFOx and HFAir provided a rapid and clinically significant reduction of dyspnea at rest in hospitalized cancer patients even when they were non-hypoxemic, supporting a role for high flow devices to provide palliation beyond oxygenation. Larger studies are needed to confirm these findings. Clinical trial information: NCT02932332 .

scholarly journals Association of Flow Rate of Prehospital Oxygen Administration and Clinical Outcomes in Severe Traumatic Brain Injury

2021 ◽  
Vol 10 (18) ◽  
pp. 4097
Author(s):  
Won Pyo Hong ◽  
Ki Jeong Hong ◽  
Sang Do Shin ◽  
Kyoung Jun Song ◽  
Tae Han Kim ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Hospital Mortality ◽  
Flow Rate ◽  
Severe Traumatic Brain Injury ◽  
High Flow ◽  
Low Flow ◽  
Oxygen Administration ◽  
High Flow Oxygen ◽  
Oxygen Group

The goal of this study was to investigate the association of prehospital oxygen administration flow with clinical outcome in severe traumatic brain injury (TBI) patients. This was a cross-sectional observational study using an emergency medical services-assessed severe trauma database in South Korea. The sample included adult patients with severe blunt TBI without hypoxia who were treated by EMS providers in 2013 and 2015. Main exposure was prehospital oxygen administration flow rate (no oxygen, low-flow 1~5, mid-flow 6~14, high-flow 15 L/min). Primary outcome was in-hospital mortality. A total of 1842 patients with severe TBI were included. The number of patients with no oxygen, low-flow oxygen, mid-flow oxygen, high-flow oxygen was 244, 573, 607, and 418, respectively. Mortality of each group was 34.8%, 32.3%, 39.9%, and 41.1%, respectively. Compared with the no-oxygen group, adjusted odds (95% CI) for mortality in the low-, mid-, and high-flow oxygen groups were 0.86 (0.62–1.20), 1.15 (0.83–1.60), and 1.21 (0.83–1.73), respectively. In the interaction analysis, low-flow oxygen showed lower mortality when prehospital saturation was 94–98% (adjusted odds ratio (AOR): 0.80 (0.67–0.95)) and ≥99% (AOR: 0.69 (0.53–0.91)). High-flow oxygen showed higher mortality when prehospital oxygen saturation was ≥99% (AOR: 1.33 (1.01~1.74)). Prehospital low-flow oxygen administration was associated with lower in-hospital mortality compared with the no-oxygen group. High-flow administration showed higher mortality.

scholarly journals Association of flow rate of prehospital oxygen administration and clinical outcomes in severe traumatic brain injury

2021 ◽  
Author(s):  
Won Pyo Hong ◽  
Ki Jeong Hong ◽  
Sang Do Shin ◽  
Kyoung Jun Song ◽  
Tae Han Kim ◽  
...  
Keyword(s):  
Flow Rate ◽  
Oxygen Supply ◽  
Severe Trauma ◽  
High Flow ◽  
Low Flow ◽  
Optimal Flow ◽  
Oxygen Administration ◽  
High Flow Oxygen ◽  
Severe Tbi ◽  
Oxygen Group

Abstract Background To prevent hypoxia during prehospital phase is important in severe traumatic brain injury (TBI) but optimal flow rate of prehospital oxygen supply is controversial. The goal of this study is to investigate the association of prehospital oxygen administration flow on clinical outcome in severe TBI patients. Methods This is a cross-sectional observational study using emergency medical services assessed severe trauma database in South Korea. In 2013 and 2015, adult patients with severe blunt TBI (abbreviated injury scale ≥3 in head lesion) without hypoxia (< 94% of oxygen saturation in prehospital pulse oximetry) were included. Main exposure was prehospital oxygen administration flow rate (no oxygen, 1~5 L/min, 6~14 L/min, 15 L/min). Primary outcome was in-hospital mortality. A multivariate logistic regression model was used to association of prehospital oxygen supply and outcomes. Results 1,842 patients with severe TBI were included. The number of patients with no oxygen, low-flow oxygen (1~5 L/min), mid-flow oxygen (6~14 L/min), high-flow oxygen (15 L/min) was 244, 573, 607 and 418. Mortality of each group was 34.8%, 32.3%, 39.9% and 41.1%. Compared with no-oxygen group, adjusted odds (95% CI) for mortality in the low, mid, high-flow oxygen groups were 0.86 (0.62–1.20), 1.15 (0.83–1.60) and 1.21 (0.83–1.73). In the interaction analysis, low-flow oxygen showed lower mortality when prehospital saturation was 94-98% (adjusted odds ratio(AOR): 0.80 [0.67–0.95]) and ≥99% (AOR: 0.69 [0.53–0.91]). High-flow oxygen (15 L/min) showed higher mortality when prehospital saturation was ≥99% in pulse oximetry (AOR: 1.33[1.01~1.74]). Conclusions Prehospital low-flow oxygen administration was associated with lower in-hospital mortality compared with the no-oxygen group in severe TBI patients. High-flow oxygen administration showed higher mortality. Optimal flow of prehospital oxygenation according prehospital saturation could reduce mortality in severe TBI. Trial registration This study used cases retrospectively registered in the emergency medical services assessed severe trauma database.

Experimental Investigation of Pressure Fluctuations on Inner Wall of a Centrifugal Pump

2019 ◽  
Vol 36 (4) ◽  
pp. 401-410 ◽  
Author(s):  
Xiao-Qi Jia ◽  
Bao-Ling Cui ◽  
Zu-Chao Zhu ◽  
Yu-Liang Zhang
Keyword(s):  
Centrifugal Pump ◽  
Flow Rate ◽  
Pressure Fluctuation ◽  
Pressure Fluctuations ◽  
High Flow ◽  
Low Flow ◽  
Centrifugal Pumps ◽  
Flow Rates ◽  
Pressure Distributions ◽  
Blade Passing Frequency

Abstract Affected by rotor–stator interaction and unstable inner flow, asymmetric pressure distributions and pressure fluctuations cannot be avoided in centrifugal pumps. To study the pressure distributions on volute and front casing walls, dynamic pressure tests are carried out on a centrifugal pump. Frequency spectrum analysis of pressure fluctuation is presented based on Fast Fourier transform and steady pressure distribution is obtained based on time-average method. The results show that amplitudes of pressure fluctuation and blade-passing frequency are sensitive to the flow rate. At low flow rates, high-pressure region and large pressure gradients near the volute tongue are observed, and the main factors contributing to the pressure fluctuation are fluctuations in blade-passing frequency and high-frequency fluctuations. By contrast, at high flow rates, fluctuations of rotating-frequency and low frequencies are the main contributors to pressure fluctuation. Moreover, at low flow rates, pressure near volute tongue increases rapidly at first and thereafter increases slowly, whereas at high flow rates, pressure decreases sharply. Asymmetries are observed in the pressure distributions on both volute and front casing walls. With increasing of flow rate, both asymmetries in the pressure distributions and magnitude of the pressure decrease.

scholarly journals Remdesivir as a tool to relieve hospital care systems stressed by COVID-19: A modelling study on bed resources and budget impact

2021 ◽  
Author(s):  
Guillaume Béraud ◽  
Jean-François Timsit ◽  
Henri Leleu
Keyword(s):  
Epidemiological Data ◽  
High Flow ◽  
Low Flow ◽  
Bed Occupancy ◽  
Agent Based ◽  
High Flow Oxygen ◽  
Hospital Bed ◽  
Care Systems ◽  
Hospital Stays ◽  
Second Wave

AbstractRemdesivir and dexamethasone are the only drugs providing reductions in the lengths of hospital stays for COVID-19 patients. We assessed the impacts of remdesivir on hospital-bed resources and budgets affected by the COVID-19 outbreak. A stochastic agent-based model was combined with epidemiological data available on the COVID-19 outbreak in France and data from two randomized control trials. Strategies involving treating with remdesivir only patients with low-flow oxygen and patients with low-flow and high-flow oxygen were examined. Treating all eligible low-flow oxygen patients during the entirety of the second wave would have decreased hospital-bed occupancy in conventional wards by 4% [2%; 7%] and intensive care unit (ICU)-bed occupancy by 9% [6%; 13%]. Extending remdesivir use to high-flow-oxygen patients would have amplified reductions in ICU-bed occupancy by up to 14% [18%; 11%]. A minimum remdesivir uptake of 20% was required to observe decreases in bed occupancy. Dexamethasone had effects of similar amplitude. Depending on the treatment strategy, using remdesivir would, in most cases, generate savings (up to 722€) or at least be cost neutral (an extra cost of 34€). Treating eligible patients could significantly limit the saturation of hospital capacities, particularly in ICUs. The generated savings would exceed the costs of medications.

scholarly journals 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 ◽  
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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