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Analysis of the Efficacy of High-Flow Nasal Cannula Oxygen Therapy and Non-Invasive Ventilation in COPD Patients
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作者 Xue Yin Yan Li +6 位作者 Yan Ma Yue Sun Li Li Wenmei Yan Jianhua Zhang He Zhang Haisheng Yang 《Journal of Clinical and Nursing Research》 2025年第11期307-315,共9页
Patients with acute exacerbation of chronic obstructive pulmonary disease(COPD)often suffer from respiratory failure and require respiratory support therapy.High-flow nasal cannula oxygen therapy(HFNC)and non-invasive... Patients with acute exacerbation of chronic obstructive pulmonary disease(COPD)often suffer from respiratory failure and require respiratory support therapy.High-flow nasal cannula oxygen therapy(HFNC)and non-invasive positive pressure ventilation(NIPPV)are commonly used non-invasive respiratory support methods.HFNC can provide precisely heated and humidified high-flow oxygen,reducing dead space and increasing alveolar ventilation.NIPPV can supply stable high-concentration oxygen and improve gas exchange.This article reviews the application of HFNC and NIPPV in the acute exacerbation stage of COPD,aiming to provide references for reasonable clinical selection. 展开更多
关键词 Chronic obstructive pulmonary disease high-flow nasal cannula oxygen therapy Non-invasive ventilation Acute exacerbation stage
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High-flow nasal cannula oxygen therapy and noninvasive ventilation for preventing extubation failure during weaning from mechanical ventilation assessed by lung ultrasound score: A single-center randomized study 被引量:12
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作者 Shan-xiang Xu Chun-shuang Wu +1 位作者 Shao-yun Liu Xiao Lu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2021年第4期274-280,共7页
BACKGROUND: We sought to demonstrate the superiority of a targeted therapy strategy involving high-flow nasal cannula oxygen(HFNCO_(2)) therapy and noninvasive ventilation(NIV) using lung ultrasound score(LUS) in comp... BACKGROUND: We sought to demonstrate the superiority of a targeted therapy strategy involving high-flow nasal cannula oxygen(HFNCO_(2)) therapy and noninvasive ventilation(NIV) using lung ultrasound score(LUS) in comparison with standard care among patients in the intensive care unit(ICU) who undergo successful weaning to decrease the incidence of extubation failure at both 48 hours and seven days.METHODS: During the study period, 98 patients were enrolled in the study, including 49 in the control group and 49 in the treatment group. Patients in the control group and patients with an LUS score <14 points(at low risk of extubation failure) in the treatment group were extubated and received standard preventive care without NIV or HFNCO_(2). Patients with an LUS score ≥14 points(at high risk of extubation failure) in the treatment group were extubated with a second review of the therapeutic optimization to identify and address any persisting risk factors for postextubation respiratory distress;patients received HFNCO2 therapy combined with sessions of preventive NIV(4-8 hours per day for 4-8 sessions total) for the first 48 hours after extubation.RESULTS: In the control group, 13 patients had the LUS scores ≥14 points, while 36 patients had scores <14 points. In the treatment group, 16 patients had the LUS scores ≥14 points, while 33 patients had scores <14 points. Among patients with the LUS score ≥14 points, the extubation failure rate within 48 hours was 30.8% in the control group and 12.5% in the treatment group, constituting a statistically significant difference(P<0.05). Conversely, among patients with an LUS score <14 points, 13.9% in the control group and 9.1% in the treatment group experienced extubation failure(P=0.61). The length of ICU stay(9.4±3.1 days vs. 7.2±2.4 days) was significantly different and the re-intubation rate(at 48 hours: 18.4% vs. 10.2%;seven days: 22.4% vs. 12.2%) significantly varied between the two groups(P<0.05). There was no significant difference in the 28-day mortality rate(6.1% vs. 8.2%) between the control and treatment groups.CONCLUSIONS: Among high-risk adults being weaned from mechanical ventilation and assessed by LUS, the NIV+HFNCO_(2) protocol does not lessen the mortality rate but reduce the length of ICU stay, the rate of extubation failure at both 48 hours and seven days. 展开更多
关键词 high-flow nasal cannula oxygen Noninvasive ventilation Lung ultrasound EXTUBATION
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Statistical modelling for effect of mix-parameters on properties of high-flowing sand-concrete 被引量:7
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作者 T.BOUZIANI A.BENMOUNAH M.BDRINA 《Journal of Central South University》 SCIE EI CAS 2012年第10期2966-2975,共10页
The high-flowing sand-concrete (HFSC) containing natural sands as aggregate was carried out. The high fluidity and stability of HFSC can be achieved by tailoring the mix design parameters, such as fine to coarse san... The high-flowing sand-concrete (HFSC) containing natural sands as aggregate was carried out. The high fluidity and stability of HFSC can be achieved by tailoring the mix design parameters, such as fine to coarse sand ratio, dosage of additions, water to binder ratio and dosage of admixtures. Mini-cone slump test, v-fl.mnel time test and viscosity model parameters were used to characterize the behaviour of HFSC in fresh state. The mechanical compressive strength in 28 d was also determined. A factorial design approach was used to establish models highlighting the effect of each mix-parameter on measured properties of HFSC. The derived models are valid for mixtures made with 0 to 0.3 of dune sand to total sand ratio, 82 to 418 kg/m3 of marble powder, 0.42 to 0.46 of water/binder ratio and 1.3% to 1.9% of superplasticizer high water-reducer. The results show that the derived models constitute very efficient means for understanding the influence of key mix-parameters on HFSC properties and are useful in selecting the optimum mix proportions, by simulating their impact on fluidity, stability and compressive strength. 展开更多
关键词 high-flowing sand-concrete factorial design FLUIDITY VISCOSITY mix-design parameters
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Influence of fly ash on early-age cracking behavior of high-flowing concrete 被引量:5
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作者 郑建岚 王雪芳 《Journal of Central South University》 SCIE EI CAS 2009年第2期312-319,共8页
The effects of quality and content of fly ash on the early-age cracking behavior of high-flowing concrete (HFC) were investigated. The early-age cracking behavior of the HFC was analyzed by combining the tests of ev... The effects of quality and content of fly ash on the early-age cracking behavior of high-flowing concrete (HFC) were investigated. The early-age cracking behavior of the HFC was analyzed by combining the tests of evaporation capacity and electrical resistivity of the HFC. In these tests, a modified flat-type specimen was adopted. The results show that the HFC will have a lower evaporation capacity when it is mixed with fine fly ash, while it will have a higher evaporation capacity when grade II! fly ash is used as mineral admixture. And the electrical resistivity rate of HFC reduces with the increase of the content of fly ash. A nonlinear relationship exists between the cracking time of HFC and the minimum electrical resistivity. The early-age cracking behavior of HFC with fly ash can be enhanced by appropriately increasing the fine particle content and MgO, K2O, and SO3 contents of fly ash. The optimal content of fly ash, which makes a satisfied early-age cracking behavior of HFC, is obtained. And when the content of fly ash exceeds a critical value, the early-age cracking behavior of HFC will rapidly decrease. 展开更多
关键词 high-flowing concrete fly ash cracking behavior electrical resistivity
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Design and Experiment-Based Optimization of High-Flow Hydraulic One-Way Valves 被引量:4
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作者 Lei Liu Ping Yu 《Fluid Dynamics & Materials Processing》 EI 2020年第2期211-224,共14页
High-flow hydraulic one-way valves in water pipes are typically used to mitigate conditions,which would otherwise cause vibration and cavitation erosion after long-term operation.To prevent cavitation and enhance the ... High-flow hydraulic one-way valves in water pipes are typically used to mitigate conditions,which would otherwise cause vibration and cavitation erosion after long-term operation.To prevent cavitation and enhance the performance of hydraulic one-way valves,in the present work a dedicated experimental study has been conducted.The structural parameters relating to the pilot valve core,the main valve core,and the through-flow section of the considered flow channel have been changed to analyse reverse impact,and cavitation,characteristics.The results show that the control pressure has a weak effect on the cavitation characteristics,while changes in the structural parameters can significantly affect them.In particular,the cavitation index,representing the extent of cavitation,has been found to display a linear correlation with the inlet pressure,but,not with the inlet flow rate.Most importantly,a stepped throttling structure can reduce the pressure oscillation,improve the response speed,enhance the impact characteristics,and decrease the likelihood and severity of cavitation.The larger the flow passage area,the shorter the unloading time.Cavitation mainly occurs when the pilot valve core is fully opened.The stepped main valve core throttling structure has been found to be an optimal option. 展开更多
关键词 high-flow structural design IMPACT CAVITATION
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Dynamic characteristics of the high-flow water three-way valve 被引量:2
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作者 Chuan-Li WANG Xia GAO Hai-Shun DENG Yu HUANG 《Journal of Coal Science & Engineering(China)》 2013年第3期392-395,共4页
Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated nu... Operating principle of water three-way valve with high flow for individual hydraulic prop in coal was presented in this paper, its strict and precise mathematical model was established, its flow field was simulated numerically by software Fluent, and its dynamic characteristics were analyzed during the work process such as raising leg, loading and overflow, the influence of the related parameters on high-flow water three-way valve was determined. The results as follows: during the raising leg stage and early raising leg stage, when the damping ratio increases, the overshoot of system decreases and the setting time reduces, and the dynamic response performance has a significant improvement. During the loading stage and the overflow stage, the pressure in plunger chamber of single hydraulic prop, the output flow and the displacement of the high-flow water three-way valve decrease with the decreasing of the external load. The spring stiffness of the safety valve directs the flow and the spool's displacement of the safety valve, and it can be used to control the high-flow three-way valve's sensitivity. 展开更多
关键词 high-flow three-way valve water hydraulic structural design dynamic characteristics
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Sleep Quality for Patients Receiving Noninvasive Positive Pressure Ventilation and Nasal High-Flow Oxygen Therapy in an ICU: Two Case Studies 被引量:1
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作者 Hiroaki Murata Yoko Yamaguchi 《Open Journal of Nursing》 2018年第9期605-615,共11页
Aim: The purpose of this case study was to examine the sleep quality of patients receiving noninvasive positive pressure ventilation (NPPV) or nasal high-flow oxygen therapy (NHF) in an intensive care unit and to inve... Aim: The purpose of this case study was to examine the sleep quality of patients receiving noninvasive positive pressure ventilation (NPPV) or nasal high-flow oxygen therapy (NHF) in an intensive care unit and to investigate what types of nursing support are offered to such patients. Methods: We examined one patient each for NPPV and NHF. Polysomnography (PSG), review of the patient charts, and semi-structured interviews were used to collect the data for analysis. Results: Patients treated with NPPV or NHF demonstrated a noticeable reduction in deep sleep, with most of their sleep being shallow. Their sleep patterns varied greatly from those of healthy individuals. These results suggest that, in addition to experiencing extremely fragmented sleep, sleep in these patients was more likely to be interrupted by nursing interventions, such as during auscultation of breath sounds. Furthermore, it was revealed that “anxiety or discomfort that accompanies the mask or air pressure” in patients treated with NPPV and “discomfort that accompanies the nasal cannula or NHF circuit” in patients treated with NHF may be primary causes of disrupted sleep. Our results suggest a need for nursing care aimed at improving sleep quality in patients treated with NPPV or NHF. 展开更多
关键词 Noninvasive Positive Pressure Ventilation (NPPV) NASAL high-flow Oxygen Therapy (NHF) Sleep DEPRIVATION ICU Post Intensive Care Syndrome (PICS)
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Efficacy of high-flow nasal cannula on acute exacerbation of chronic obstructive pulmonary disease: A meta-analysis 被引量:1
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作者 Ying-Ming Sun Min Zhang +2 位作者 Na Sun Zhi Guan Ying Wang 《Medical Data Mining》 2019年第4期142-149,共8页
Objective:To systematically evaluate the efficacy and feasibility of high-flow nasal cannula(HFNC)on patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:Systematic searches on Pub... Objective:To systematically evaluate the efficacy and feasibility of high-flow nasal cannula(HFNC)on patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:Systematic searches on PubMed,Web of Science,the Cochrane Library,Embase,CBM(Chinese Biomedicine Database),CNKI(China National Knowledge Infrastructure),Wanfang Database and VIP were performed for randomized controlled trials(RCTs)which explored the effects of HFNC on patients with AECOPD.The retrieval time was from the establishment of each database to July 2019.RevMan5.3 software was used for statistical analysis.Results:A total of 12 articles were included,involving 812 patients.The results showed that:(1)Compared with conventional oxygen therapy,HFNC could improve patients'arterial partial oxygen pressure(PaO2)(MD=12.70,95%CI(7.00,18.40),Z=4.37,P<0.0001),reduce partial arterial blood carbon dioxide(PaCO2)(MD=-10.99,95%CI(-14.42,-7.55),Z=6.26,P<0.00001)and reduce endotracheal intubation rate(OR=0.19,95%CI(0.04,0.93),Z=2.05,P=0.04),shorten the hospitalization time(SMD=-0.74,95%CI(-1.11,-0.37),Z=3.95,P<0.0001).(2)Compared with non-invasive positive pressure ventilation,it has fewer adverse reactions(OR=0.18,95%CI(0.09,0.35),Z=5.08,P<0.00001)and shorter hospital stay(SMD=-0.57,95%CI(-0.90,-0.23),Z=3.33,P=0.0009).Conclusion:HFNC can improve the patients’hypoxia symptoms and CO2 retention,reduce the rate of tracheal intubation,and alleviate adverse reactions.However,Limited by the quality and region of the included studies,more high-quality are needed to test it. 展开更多
关键词 high-flow nasal cannula AECOPD Non-invasive positive pressure ventilation Conventional oxygen therapy META-ANALYSIS
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Prone position combined with high-flow nasal oxygen could benefit spontaneously breathing, severe COVID-19 patients:A case report
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作者 Da-Wei Xu Guang-Liang Li +1 位作者 Jiong-Han Zhang Fei He 《World Journal of Clinical Cases》 SCIE 2021年第17期4381-4387,共7页
BACKGROUND Since the outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China in December 2019,the overall fatality rate of severe and critical patients with COVID-19 is high and the effective therapy is limited.C... BACKGROUND Since the outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China in December 2019,the overall fatality rate of severe and critical patients with COVID-19 is high and the effective therapy is limited.CASE SUMMARY In this case report,we describe a case of the successful combination of the prone position(PP)and high-flow nasal oxygen(HFNO)therapy in a spontaneously breathing,severe COVID-19 patient who presented with fever,fatigue and hypoxemia and was diagnosed by positive throat swab COVID-19 RNA testing.The therapy significantly improved the patient's clinical symptoms,oxygenation status,and radiological characteristics of lung injury during hospitalization,and the patient showed good tolerance and avoided intubation.Additionally,we did not find that medical staff wearing optimal airborne personal protective equipment(PPE)were infected by the new coronavirus in our institution.CONCLUSION We conclude that the combination of PP and HFNO could benefit spontaneously breathing,severe COVID-19 patients.The therapy does not increase risk of healthcare workers wearing optimal airborne PPE to become infected with virus particles. 展开更多
关键词 COVID-19 HYPOXEMIA high-flow nasal oxygen Intubation and prone position Case report
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Efficacy and Safety of Treatment of High-flow Priapism with Superselective Transcatheter Embolization
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作者 Tao QI Lei YE +5 位作者 Zheng CHEN Zhan-sen HUANG Bo WANG Hao LI Bin ZHANG Jun CHEN 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2018年第1期101-106,共6页
This study is aimed to evaluate the effectiveness and safety of the treatment of highflow priapism with superselective transcatheter embolization.From Sep.1999 to Jan.2013,six patients with high-flow priapism underwen... This study is aimed to evaluate the effectiveness and safety of the treatment of highflow priapism with superselective transcatheter embolization.From Sep.1999 to Jan.2013,six patients with high-flow priapism underwent superselective transcatheter embolization of the cavernous artery.Recurrence of priapism,and change in erectile function detected by nocturnal penile tumescence and rigidity(NPTR)test and the International Index of Erectile Function 5-item questionnaire(IIEF-5)were evaluated during a mean follow-up of 12 months.A single superselective transcatheter embolization was sufficient for complete resolution of priapism in the six patients.None of the patients had a relapse of priapism after embolization,and all the patients who had premorbid normal erectile function showed maintained potency with normal results of NPTR and a mean postoperative IIEF-5 score of 23.5(range 23 to 24)during the follow-up period.In conclusion,superselective transcatheter embolization is an effective and safe treatment method for high-flow priapism,and it can ensure a high level of preservation of premorbid erectile function. 展开更多
关键词 high-flow priapism superselective transcatheter embolization
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Analysis of the Efficacy of Humidified High-Flow Nasal Oxygen Therapy Combined with Alveolar Lavage in the Treatment of Patients with Severe Pneumonia Complicated with Respiratory Failure
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作者 Lianyu Zhang 《Journal of Clinical and Nursing Research》 2023年第3期112-117,共6页
Objective:To analyze the curative effect of humidified high-flow nasal oxygen therapy combined with alveolar lavage in patients with severe pneumonia and respiratory failure.Methods:120 patients with severe pneumonia ... Objective:To analyze the curative effect of humidified high-flow nasal oxygen therapy combined with alveolar lavage in patients with severe pneumonia and respiratory failure.Methods:120 patients with severe pneumonia complicated with respiratory failure admitted to the Third People’s Hospital of Xining from July 2021 to December 2022 were randomly divided into two groups:group A and group B.The patients in group A were given humidified high-flow nasal oxygen therapy combined with alveolar lavage,whereas those in group B were given humidified high-flow nasal oxygen therapy.The treatment efficacy,blood gas analysis results,and differences in inflammatory mediators were compared between the two groups.Results:The curative effect in group A(96.67%)was significantly higher than that in group B(81.67%),P<0.05;the partial pressure of carbon dioxide(PaCO2),partial pressure of oxygen(PaO2),oxygen saturation(SpO2),and Horowitz index(P/F)of group A were significantly better than group B,P<0.05;the interleukin 6(IL-6),tumor necrosis factor alpha(TNF-α),and C-reactive protein(CRP)levels,white blood cell(WBC)count,serum procalcitonin(PCT),and neutrophil(N)percentage of group A were significantly lower than those of group B,P<0.05.Conclusion:For patients with severe pneumonia complicated with respiratory failure,alveolar lavage,on the basis of humidified high-flow oxygen therapy,can inhibit local inflammation,improve blood gas analysis results,promote disease recovery,and improve the clinical treatment effect。 展开更多
关键词 Alveolar lavage high-flow oxygen therapy Humidified nasal oxygen therapy Severe pneumonia Respiratory failure
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Impact and Management under Extracorporeal Circulation of a Patient with Renal Insufficiency on Dialysis with a High-Flow Arteriovenous Fistula in the Cardiac Surgery Department of the Angers Teaching Hospital about a Case and Review of the Literature
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作者 Abdoulaye Kanté Bréhima Coulibaly +6 位作者 Mamadou Diakité Mamadou A. Keita Bakary Keita Drissa Traoré Nouhoum Ongoïba Patrice Binuani Christophe Baufreton 《Open Journal of Thoracic Surgery》 2023年第1期1-5,共5页
Arteriovenous fistulas have a substantial impact on systemic hemodynamics, however their effect on extracorporeal circulation is not well understood. We report our clinical observation on the management under extracor... Arteriovenous fistulas have a substantial impact on systemic hemodynamics, however their effect on extracorporeal circulation is not well understood. We report our clinical observation on the management under extracorporeal circulation of a patient with renal insufficiency with a high-flow arteriovenous fistula. This is a 59-year-old man who was referred to us for surgical treatment of ischemic coronary artery disease in a context of anuric chronic renal failure. Hypothermia at 32°C is started from the start in CEC due to hyperflow at the level of the arteriovenous fistula. We performed two coronary artery bypasses of the marginal and IVA via the two internal thoracic arteries. The patient is hemofiltered in order to avoid hyperkalaemia and possibly avoid fluid overload related to filling per CEC. The clamping time was 71 minutes and the SCC lasted 141 minutes. There was no homologous transfusion in the operating room. It turns out that the input/output balance is zero at the end of the CEC. The postoperative course was simple. 展开更多
关键词 Coronaryartery by Pass Grafting High Flow Arteriovenous Fistula Extracorporeal Circulation HYPOTHERMIA
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Physiological effects and clinical evidence of high-flow nasal cannula during acute exacerbation in COPD patients: A narrative review
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作者 Nicolás Colaianni-Alfonso Federico Herrera +5 位作者 Diego Flores Cristian Deana Mina Vapireva Daniele Guerino Biasucci Salvatore Maurizio Maggiore Luigi Vetrugno 《Journal of Intensive Medicine》 2025年第2期127-133,共7页
Chronic obstructive pulmonary disease(COPD)is one of the leading causes of death worldwide.During severe exacerbations,COPD patients may develop acute respiratory failure(ARF),often necessitating hospital admission du... Chronic obstructive pulmonary disease(COPD)is one of the leading causes of death worldwide.During severe exacerbations,COPD patients may develop acute respiratory failure(ARF),often necessitating hospital admission due to impaired gas exchange.In COPD patients,the diaphragm is subjected to an increased workload resulting from airflow limitations and geometric changes in the thorax due to pulmonary hyperinflation.Noninvasive ventilation(NIV)plays a crucial role in managing type II ARF by improving alveolar ventilation,reducing the work of breathing,minimizing the need for endotracheal intubation(ETI),and decreasing both hospital stays and mortality rates.Studies have shown that approximately 64%of patients with acute exacerbation of COPD(AECOPD)may fail NIV,primarily due to worsening respiratory function,interface intolerance,cardiovascular instability,or neurological deterioration.For patients intolerant to NIV,a trial with a high-flow nasal cannula(HFNC)is recommended.Recently,HFNC has gained popularity as a novel respiratory support system and is increasingly used in routine clinical practice for AECOPD patients.It delivers warmed,humidified,and oxygen-enriched air through a nasal cannula at flow rates of up to 60 L/min.This narrative review aims to describe the physiological effects of HFNC in the COPD population and provide an updated overview of HFNC’s role in AECOPD patients requiring hospitalization. 展开更多
关键词 Chronic obstructive pulmonary disease Respiratory failure HYPERCAPNIA Respiratory physiology high-flow nasal oxygen
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High-flow nasal oxygen is the reference treatment in acute hypoxemic respiratory failure: Pro
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作者 Jean-Pierre Frat Sylvain Le Pape 《Journal of Intensive Medicine》 2025年第3期222-229,共8页
In patients with hypoxemic acute respiratory failure(ARF),the first-line treatment is oxygen therapy,which may include the administration of high-flow nasal oxygen(HFNO),noninvasive ventilation(NIV),or continuous posi... In patients with hypoxemic acute respiratory failure(ARF),the first-line treatment is oxygen therapy,which may include the administration of high-flow nasal oxygen(HFNO),noninvasive ventilation(NIV),or continuous positive airway pressure(CPAP).In addition to improving oxygenation,HFNO and NIV reduce the work of breathing as compared to standard oxygen,while CPAP does not.However,tolerance to NIV and CPAP is clinically challenging,resulting in treatment interruption in 10%-20%of cases.Compared to standard oxygen,HFNO has been shown to reduce the risk of intubation,while the benefits of NIV or CPAP,even when delivered via a helmet,require further evaluation.Although evidence for the efficacy of HFNO in reducing mortality remains inconclusive,HFNO has emerged as the reference treatment and is recommended for patients with hypoxemic ARF given its benefit in reducing the risk of intubation. 展开更多
关键词 Acute hypoxemic respiratory failure high-flow nasal oxygen Continuous positive airway pressure Continuous positive airway pressure Noninvasive ventilation
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深空探测器进入行星大气面临的极高速流动与传热基础科学问题
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作者 唐志共 张志刚 +4 位作者 粟斯尧 杨强 胡华雨 党雷宁 罗仕超 《空气动力学学报》 北大核心 2026年第1期1-5,共5页
火星采样、载人登月、木星系探测等深空探测任务中,探测器将以超行星第一宇宙速度进入地外行星大气或返回地球大气,系统能量大幅增加,出现伴随超高温物理化学反应的极高速流动与传热现象,其中涉及微观物理化学反应与宏观流动、流固界面... 火星采样、载人登月、木星系探测等深空探测任务中,探测器将以超行星第一宇宙速度进入地外行星大气或返回地球大气,系统能量大幅增加,出现伴随超高温物理化学反应的极高速流动与传热现象,其中涉及微观物理化学反应与宏观流动、流固界面传热传质,以及防热材料内部热力响应等不同时空尺度过程的复杂相互作用。如何准确描述预示这样一个多相态、多尺度、多过程强耦合的极端流动与传热系统,从而支撑探测器精细化设计,以实现动能高效耗散与热量有效隔绝,对流体力学及相关学科提出了严峻挑战。本文聚焦深空探测器进入行星大气过程中的极高速流动与传热问题,探讨梳理了极高速流动、强辐射传热、超高温物理化学反应3个方面的基础科学问题,并对我国未来该领域研究进行了展望。 展开更多
关键词 深空探测器 极高速流动 强辐射传热 超高温理化反应
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高流量吸氧在老年急性呼吸窘迫综合征患者中的应用
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作者 邵蕊 夏颖华 +3 位作者 周双 李妍 姚远 李岱 《天津科技》 2026年第3期81-84,共4页
将在天津医科大学总医院治疗的52例老年急性呼吸窘迫综合征(ARDS)患者随机分为高流量组和低流量组,每组纳入26例。对照组给予低流量吸氧(流量为3~5 L/min)干预,观察组给予高流量吸氧(流量为6~8 L/min)干预,比较两组患者接受不同干预方... 将在天津医科大学总医院治疗的52例老年急性呼吸窘迫综合征(ARDS)患者随机分为高流量组和低流量组,每组纳入26例。对照组给予低流量吸氧(流量为3~5 L/min)干预,观察组给予高流量吸氧(流量为6~8 L/min)干预,比较两组患者接受不同干预方式后血氧饱和度(SaO_(2))、氧合指数(PaO_(2)/FiO_(2))、动脉血氧分压(PaO_(2))、动脉血二氧化碳分压(PaCO_(2))、pH水平的变化情况,以及两组患者呼吸频率、浅快呼吸指数、临床疗效和并发症发生率的变化,以评估经鼻高流量氧疗对于老年ARDS患者的临床疗效。治疗后,高流量组SaO_(2)、PaO_(2)/FiO_(2)、PaO_(2)较低流量组明显升高,PaCO_(2)较低流量组下降(P<0.05),而两者的pH水平无差异(P>0.05);高流量组的呼吸频率及浅快呼吸指数低于低流量组(P<0.05)。临床结果表明,两组的总有效率及并发症发生率无统计学差异(P>0.05),但高流量组的显效率及有效率均明显高于低流量组(P<0.05)。相较于传统低流量吸氧,在老年ARDS患者中使用6~8 L/min经鼻高流量吸氧不仅可以更好地改善患者的氧合水平及呼吸力学参数,且没有明显的并发症增加情况,临床效果更佳,具备一定的临床安全性及有效性。 展开更多
关键词 高流量吸氧 老年 急性呼吸窘迫综合征 动脉血气指标
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重度支气管肺发育不良早产儿经鼻高流量家庭氧疗的护理
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作者 朱海虹 凌云 +3 位作者 尹雅郡 张丹飞 王娟 诸纪华 《中华急危重症护理杂志》 2026年第2期197-200,共4页
总结经鼻高流量氧疗(high-flownasal cannula,HFNC)在早产儿重度支气管肺发育不良(severe bronchopul-monary dysplasia,sBPD)家庭氧疗中的护理体会。回顾性分析2022年1月—2024年12月收治的6例重度sBPD早产儿HFNC家庭氧疗的临床资料,... 总结经鼻高流量氧疗(high-flownasal cannula,HFNC)在早产儿重度支气管肺发育不良(severe bronchopul-monary dysplasia,sBPD)家庭氧疗中的护理体会。回顾性分析2022年1月—2024年12月收治的6例重度sBPD早产儿HFNC家庭氧疗的临床资料,针对长期依赖家庭氧疗的早产儿sBPD,采取出院前评估及主要照顾者赋能教育,家庭氧疗的实施,根据目标SpO2确定减停计划,出现呛奶窒息、设备故障等不良事件的正确应对及按计划随访等措施,促进其生长发育,改善家庭生活质量。6例患儿HFNC家庭氧疗期间,1例因呛奶2次、1例因鼻病毒感染再入院外,其余患儿均顺利接受HFNC家庭氧疗。本组1例家庭氧疗130 d时,在吸入氧浓度(fraction of inspired oxygen,FiO2)降至25%、氧流量10 L/min时直接脱氧;2例分别家庭氧疗268 d、22 d,予序贯至低流量鼻导管吸氧后脱氧;另3例未脱氧患儿按计划随访中。 展开更多
关键词 支气管肺发育不良 高流量鼻导管氧疗 家庭氧疗 婴儿 早产 危重病护理
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高流量呼吸湿化治疗仪在肺癌合并Ⅰ型呼吸衰竭患者治疗中的应用价值
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作者 李敏燕 麦子健 +2 位作者 马萍 欧阳辉 陈海花 《临床医学工程》 2026年第2期196-200,共5页
目的分析高流量呼吸湿化治疗仪应用于肺癌合并Ⅰ型呼吸衰竭患者的临床价值。方法以随机数表法对本院2024年1月至2025年1月收治的98例肺癌合并Ⅰ型呼吸衰竭患者实施分组,对照组(n=49)采用无创呼吸机进行辅助通气治疗,观察组(n=49)采用高... 目的分析高流量呼吸湿化治疗仪应用于肺癌合并Ⅰ型呼吸衰竭患者的临床价值。方法以随机数表法对本院2024年1月至2025年1月收治的98例肺癌合并Ⅰ型呼吸衰竭患者实施分组,对照组(n=49)采用无创呼吸机进行辅助通气治疗,观察组(n=49)采用高流量呼吸湿化治疗仪进行治疗,对比两组的血气指标[动脉血氧分压(PaO_(2))、二氧化碳分压(PaCO_(2))、pH、氧合指数(OI)]、呼吸力学指标[呼吸频率(RR)、呼吸做功(WOB)、气道阻力(Raw)、气道峰压(PIP)]、肺功能指标[用力肺活量(FVC)、第1秒全力呼气容积(FEV1)、呼气流量峰值(PEF)]、血清学指标[C反应蛋白(CRP)、降钙素原(PCT)、N末端B型利钠肽原(NT-proBNP)]、临床转归指标与并发症发生情况。结果治疗24 h后,与对照组相比,观察组的PaO_(2)、p H、OI水平较高,PaCO_(2)水平较低;RR、WOB、Raw、PIP水平较低;FVC、FEV1、PEF较高;CRP、PCT、NT-proBNP水平较低;气管插管率较低,治疗成功率较高;并发症发生率较低,差异均有统计学意义(P<0.05)。结论采用高流量呼吸湿化治疗仪治疗肺癌合并Ⅰ型呼吸衰竭患者,可明显优化其血气指标、呼吸力学指标与血清学指标,改善肺功能,缓解呼吸症状,促进病情转归,降低并发症风险。 展开更多
关键词 肺癌 Ⅰ型呼吸衰竭 高流量呼吸湿化治疗仪 血气指标 呼吸力学指标 肺功能指标
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转臂式高速离心机减阻设计及机室流场特性研究
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作者 陈红永 杨鑫 +4 位作者 黎启胜 龚志斌 宋琼 李心耀 尹益辉 《应用力学学报》 北大核心 2026年第1期164-170,共7页
风阻功率是大型转臂式土工离心机驱动功率设计的重要依据,机室流场具有随流、温升、流速高等特点。为降低风阻需对转臂或吊篮采取整流减阻设计。针对两型分别采用转臂整流和整流罩减阻的离心机,开展了基于CFD(computational fluid dynam... 风阻功率是大型转臂式土工离心机驱动功率设计的重要依据,机室流场具有随流、温升、流速高等特点。为降低风阻需对转臂或吊篮采取整流减阻设计。针对两型分别采用转臂整流和整流罩减阻的离心机,开展了基于CFD(computational fluid dynamics)的气动特性仿真,通过优化仿真参数获得离心机高速运行时的机室内部流场流场特性及离心机风阻功率,并通过型线设计对离心机整流罩进行了气动阻力系数优化。研究表明:高速离心机低气压运行时机室下壁面的摩擦阻力矩占主导,高于周向壁面的摩擦阻力矩;吊篮不采用整流罩时,在迎风端面肩部出现了流动分离,压差阻力较大;采用整流罩后,吊篮前缘肩部的分离被削弱,总阻力系数大幅降低。研究表明对于高速离心机开展整流设计是必要的,通过转臂外形设计及整流罩设计,可有效降低风阻功率,更有益于控制机室温升。 展开更多
关键词 转臂式离心机 高速转动 流场 CFD 整流罩
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甲泼尼龙联合高流量湿化氧疗治疗COPD呼吸衰竭的临床评价
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作者 何小花 朱庆华 傅俊凯 《中国药物应用与监测》 2026年第3期363-367,共5页
目的观察甲泼尼龙联合高流量湿化氧疗(HFNC)对慢性阻塞性肺疾病(COPD)合并呼吸衰竭患者的疗效。方法采用回顾性队列研究设计,从义乌市中心医院2024年7月至2025年4月电子病历系统中提取符合纳入与排除标准的120例COPD合并呼吸衰竭患者的... 目的观察甲泼尼龙联合高流量湿化氧疗(HFNC)对慢性阻塞性肺疾病(COPD)合并呼吸衰竭患者的疗效。方法采用回顾性队列研究设计,从义乌市中心医院2024年7月至2025年4月电子病历系统中提取符合纳入与排除标准的120例COPD合并呼吸衰竭患者的诊疗数据,根据病历记载的治疗方法自然分为两组,由2名研究者独立提取数据并进行质量核查,Cohen’s Kappa值为0.85,常规治疗组(60例)病历记载接受常规抗感染、辅助PDCA(Plan-Do-Check-Act)康复及HFNC,甲泼尼龙组(60例)病历记载在上述治疗的基础上接受甲泼尼龙琥珀酸钠治疗,评估两组动脉血气分析指标、炎症标志物、呼吸困难改善情况以及不良反应。结果治疗后,甲泼尼龙组动脉血氧分压、血氧饱和度[分别为(72.85±6.13)mmHg(1 mmHg=0.133 kPa)、(91.20±4.13)%],高于常规治疗组[分别为(69.98±6.06)mmHg、(89.23±4.54)%],甲泼尼龙组动脉血二氧化碳分压[(42.87±5.19)mmHg]低于常规治疗组[(45.24±5.38)mmHg](t=2.579、2.486、2.456,均P<0.05);甲泼尼龙组C反应蛋白、降钙素原、血清淀粉样蛋白A水平[分别为(7.38±2.15)mg/L、(0.54±0.15)ng/L、(27.65±6.13)mg/L]均低于常规治疗组[分别为(9.75±2.27)mg/L、(0.81±0.30)ng/L、(30.81±7.20)mg/L],差异均有统计学意义(t=5.872、6.235、2.589,均P<0.05);甲泼尼龙组呼吸困难指数评分[(1.22±0.50)分]低于常规治疗组[(1.80±0.62)分],差异有统计学意义(t=5.641,P<0.05);两组不良反应发生率比较[10.00%(6/60)vs 5.00%(3/60)],差异无统计学意义(χ^(2)=1.081,P=0.298)。结论甲泼尼龙联合HFNC治疗可改善COPD合并呼吸衰竭患者氧合,减轻炎症状态和呼吸困难程度,且不增加不良反应发生风险。 展开更多
关键词 慢性阻塞性肺疾病 呼吸衰竭 甲泼尼龙 高流量湿化氧疗 回顾性队列研究
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