BACKGROUND Accurate condition assessment is critical for improving the prognosis of neonatal respiratory distress syndrome(RDS),but current assessment methods for RDS pose a cumulative risk of harm to neonates.Thus,a ...BACKGROUND Accurate condition assessment is critical for improving the prognosis of neonatal respiratory distress syndrome(RDS),but current assessment methods for RDS pose a cumulative risk of harm to neonates.Thus,a less harmful method for assessing the health of neonates with RDS is needed.AIM To analyze the relationships between pulmonary ultrasonography and respiratory distress scores,oxygenation index,and chest X-ray grade of neonatal RDS to identify predictors of neonatal RDS severity.METHODS This retrospective study analyzed the medical information of 73 neonates with RDS admitted to the neonatal intensive care unit of Liupanshui Maternal and Child Care Service Center between April and December 2022.The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest Xray grade of each newborn before and after treatment were collected.Spearman correlation analysis was performed to determine the relationships among these values and neonatal RDS severity.RESULTS The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest X-ray RDS grade of the neonates were significantly lower after treatment than before treatment(P<0.05).Spearman correlation analysis showed that before and after treatment,the pulmonary ultrasonography score of neonates with RDS was positively correlated with the respiratory distress score,oxygenation index,and chest X-ray grade(ρ=0.429–0.859,P<0.05).Receiver operating characteristic curve analysis indicated that pulmonary ultrasonography screening effectively predicted the severity of neonatal RDS(area under the curve=0.805–1.000,P<0.05).CONCLUSION The pulmonary ultrasonography score was significantly associated with the neonatal RDS score,oxygenation index,and chest X-ray grade.The pulmonary ultrasonography score was an effective predictor of neonatal RDS severity.展开更多
<strong>Objective:</strong> Coronavirus disease 2019 (COVID-19) spread throughout the world and caused hundreds of thousands of infected people to death. However, the pathogenesis of severe acute respirato...<strong>Objective:</strong> Coronavirus disease 2019 (COVID-19) spread throughout the world and caused hundreds of thousands of infected people to death. However, the pathogenesis of severe acute respiratory syndrome coronavirus-2 (SARS COV-2) is poorly understood. The objective of this study is to retrospectively explore the pathogenesis of COVID-19 from clinical laboratory findings, taking disease progression into account. <strong>Methods:</strong> A single-centered, retrospective study was carried out, which included moderate (n = 76) and severe COVID-19 cases (n = 22). The difference of laboratory findings from blood routine examination and hepatorenal function test were retrospectively evaluated between the state of moderate and severe. The disease progression was indicated by oxygenation index. <strong>Results: </strong>Age is a risk factor for disease progression from moderate to severe. Lymphocytopenia, neutrophilia, liver and kidney function decreasement occurred in severe patients on admission, compared with moderate patients. Lymphocytopenia and neutrophilia deteriorated at the lowest oxygenation index timepoint in the severe patients. And the oxygenation index was associated with ratio of lymphocyte and neutrophil in COVID-19 patients. <strong>Conclusions:</strong> Lymphocytopenia and neutrophilia, which deteriorate in the progression of severe patients, are the main pathogenesis of COVID-19. More measures need to be taken to control lymphocytopenia and neutrophilia in severe COVID-19. Oxygenation index presented potentiality as predictor on the progression of COVID-19.展开更多
BACKGROUND:Animal experiments showed that recruitment maneuver (RM) and protective ventilation strategy of the lung could improve oxygenation and reduce extravascular lung water. This study was to investigate the e...BACKGROUND:Animal experiments showed that recruitment maneuver (RM) and protective ventilation strategy of the lung could improve oxygenation and reduce extravascular lung water. This study was to investigate the effects of RM on respiratory mechanics and extravascular lung water index (EVLWI) in patients with acute respiratory distress syndrome (ARDS). METHODS:Thirty patients with ARDS were randomized into a RM group and a non-RM group. In the RM group, after basic mechanical ventilation stabilized for 30 minutes, RM was performed and repeated once every 12 hours for 3 days. In the non-RM group, lung protective strategy was conducted without RM. Oxygenation index (PaO2/FiO2), peak inspiratory pressure (PIP), Plateau pressure (Pplat), static pulmonary compliance (Cst) and EVLWI of patients before treatment and at 12, 24, 48, 72 hours after the treatment were measured and compared between the groups. Hemodynamic changes were observed before and after RM. One-way ANOVA, Student's t test and Fisher's exact test were used to process the data. RESULTS:The levels of PaO2/FiO2 and Cst increased after treatment in the two groups, but they were higher in the RM group than in the non-RM group (P〈0.05). The PIP and Pplat decreased after treatment in the two groups, but they were lower in the RM group than in the non-RM group (P〈0.05). The EVLWI in the two groups showed downward trend after treatment (P〈0.05), and the differences were signifcant at all time points (P〈0.01); the EVLWI in the RM group was lower than that in the non-RM group at 12, 24, 48 and 72 hours (P〈0.05 or P〈0.01). Compared with pre-RM, hemodynamics changes during RM were significantly different (P〈0.01); compared with pre-RM, the changes were not significantly different at 120 seconds after the end of RM (P〉0.05). CONCLUSIONS: RM could reduce EVLWI, increase oxygenation and lung compliance. The effect of RM on hemodynamics was transient.展开更多
Biochemical, anatomical, and physiological characteristics of the brain make it especially vulnerable to insult. Specifically, some of these characteristics such as myelin and a high energy requirement provide for the...Biochemical, anatomical, and physiological characteristics of the brain make it especially vulnerable to insult. Specifically, some of these characteristics such as myelin and a high energy requirement provide for the introduction of free radical-induced insult. Recently, the biochemistry of free radicals has received considerable attention. It also has become increasingly suggestive that many drug and chemical-induced toxicities may be evoked via free radicals and oxidative stress. Major points addressed in this work are the regulation of neural-free radical generation by antioxidants and protective enzymes, xenobiotic-induced disruption of cerebral redox status, and specific examples of neurotoxic agent-induced alterations in free radicals as measured by the fluorescent probe dichlorofluorescein. This article considers that free radical mechanisms may contribute significantly to the properties of several diverse neurotoxic agents and proposes that free radicals may be common phenomena of neurotoxicity.展开更多
BACKGROUND:High-volume hemofiltration (HVHF) is technically possible in severe acute pancreatitis (SAP) patients complicated with multiple organ dysfunction syndrome (MODS). Continuous HVHF is expected to becom...BACKGROUND:High-volume hemofiltration (HVHF) is technically possible in severe acute pancreatitis (SAP) patients complicated with multiple organ dysfunction syndrome (MODS). Continuous HVHF is expected to become a beneficial adjunct therapy for SAP complicated with MODS. In this study, we aimed to explore the effects of fluid resuscitation and HVHF on alveolar- arterial oxygen exchange, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score in patients with refractory septic shock. METHODS:A total of 89 refractory septic shock patients, who were admitted to ICU, the Provincial Hospital affiliated to Shandong University from August 2006 to December 2009, were enrolled in this retrospective study. The patients were randomly divided into two groups: fluid resuscitation (group A, n=41), and fluid resuscitation plus high-volume hemofiltration (group B, n=48), The levels of O2 content of central venous blood (CcvO2), arterial oxygen content (CaO2), alveolar-arterial oxygen pressure difference P(A-a)DO2, ratio of arterial oxygen pressure/alveolar oxygen pressure (PaO2/ PAO2), respiratory index (RI) and oxygenation index (OI) were determined. The oxygen exchange levels of the two groups were examined based on the arterial blood gas analysis at different times (0, 24, 72 hours and 7 days of treatment) in the two groups. The APACHE II score was calculated before and after 7-day treatment in the two groups. The levels of CcvO2, CaO2 on day 7 in group A were significantly lower than those in group B (CcvO2:0.60±0.24 vs, 0.72±0.28, P〈0.05; CaO2:0.84±0.43 vs. 0.94±0.46, P〈0.05). The level of oxygen extraction rate (O2ER) in group A on the 7th day was significantly higher than that in group B ( 28.7±2.4 vs. 21.7±3.4, P〈0.01). The levels of P(A-a)DO2 and RI in group B on the 7th day were significantly lower than those in group A. The levels of PaO2/PAO2 and OI in group B on 7th day were significantly higher than those in group A (P〈0.05 or P〈0.01). The APACHE II score in the two groups reduced gradually after 7-day treatment, and the APACHE II score on the 7th day in group B was significantly lower than that in group A (8.2±3.8 vs. 17.2±6.8, P〈0.01). HVHF combined with fluid resuscitation can improve alveolar- arterial-oxygen exchange, decrease the APACHE II score in patients with refractory septic shock, and thus it increases the survival rate of patients.展开更多
BACKGROUND Aortic dissection is a complex and dangerous cardiovascular disease,with many complications in the perioperative period,including severe acute respiratory distress syndrome(ARDS),which affects prognosis and...BACKGROUND Aortic dissection is a complex and dangerous cardiovascular disease,with many complications in the perioperative period,including severe acute respiratory distress syndrome(ARDS),which affects prognosis and increases mortality.Despite the effect of prone positioning(PP)in improving oxygenation in patients with severe ARDS,reports about PP early after cardiac surgery are few and such an opt-ion may be an issue in cardiac surgery patients because of the recent sternotomy.CASE SUMMARY A 40-year-old male patient diagnosed with acute type A aortic dissection on October 22,2021 underwent ascending artery replacement plus total aortic arch replacement plus stent elephant trunk implantation under cardiopulmonary bypass.Unfortunately,he developed ARDS on postoperative day 1.Despite comprehensive treatment with aggressive pulmonary protective ventilation,fluid management with continuous renal replacement therapy,the condition continued to deteriorate and rapidly progressed to severe ARDS with a minimum oxygenation index of 51.We are ready to implement salvage therapy,including PP and extracorporeal membrane oxygenation(ECMO).Due to the large amount of pericardial mediastinal and thoracic drainage after thoracotomy,ECMO may result in massive postoperative bleeding.Prolonged prone ventilation is often inappropriate after thoracotomy.Therefore,we chose short-term PP for<6 h.Finally,the oxygenation index greatly improved and the diffuse exudation in both lungs of the patient was significantly reduced with short-term prone positioning.CONCLUSION Intermittent short-term PP can improve early postoperative severe ARDS after acute aortic dissection.展开更多
[Objectives]To systematically evaluate the effects of early-stage phased rehabilitation training on the oxygenation index,ICU length of stay,duration of mechanical ventilation,and occurrence of complications(ventilato...[Objectives]To systematically evaluate the effects of early-stage phased rehabilitation training on the oxygenation index,ICU length of stay,duration of mechanical ventilation,and occurrence of complications(ventilator-associated pneumonia,pressure ulcers,delirium)in ARDS patients,thus contributing evidence for the clinical application of early-stage phased rehabilitation training.[Methods]The China National Knowledge Infrastructure(CNKI),Wanfang,and other databases were searched.Literature screening,data extraction,and systematic analysis of the included studies were performed using Revman software.[Results]Thirteen randomized controlled trials involving a total of 860 patients were included in this review.The results of the meta-analysis showed that compared to the traditional rehabilitation training group,the early-stage phased rehabilitation training group demonstrated a significant increase in the oxygenation index of ARDS patients[SMD=1.18,95%CI(1.01,1.35),P<0.01],with statistically significant differences.Furthermore,there were significant reductions in ICU length of stay[SMD=-0.70,95%CI(-0.90,-0.50),P<0.01],duration of mechanical ventilation[SMD=-1.15,95%CI(-1.36,-0.94),P<0.01],and occurrence of complications[OR=0.16,95%CI(0.10,0.26),P<0.01],all of which were statistically significant.[Conclusions]Early-stage phased pulmonary rehabilitation training for ARDS patients effectively improves the oxygenation index,shortens ICU length of stay and duration of mechanical ventilation,and reduces complications.These findings support the clinical application and promotion of early-stage phased rehabilitation training.展开更多
The article provides information on our achievements in the application of modern diagnostic methods and modern methods of treating patients with viral pneumonia,confirmed by covid-19.For this,statistical data of 2,00...The article provides information on our achievements in the application of modern diagnostic methods and modern methods of treating patients with viral pneumonia,confirmed by covid-19.For this,statistical data of 2,000 patients were used.Of the 2,000 patients treated,920 were men,1,070 were women and 10 were children.Viral pneumonia-glaucoma syndrome in 1650 out of 2,000 patients with 10-20%damage;In 350,the diagnosis of viral pneumonia-frostbite syndrome with 50-85%damage,CRDS,respiratory failure was confirmed.Thus,50 out of 350 patients treated at the intensive care unit(ICU)out of 2,000 were intubated and connected to artificial ventilation.The research was carried out in 3 stages:I stage-admission to the intensive care unit;II stage-from the day of intubation to spontaneous breathing(7-14 days);and III stage-covers the period of extubation and recovery.The results of clinical,functional,hemodynamic and echocardiographic studies of the patients participating in the examination were analyzed.Also,the patients underwent bacteriological research studied the sensitivity to antibiotics.In addition,the composition of blood gases and the oxygenation index-Carrico were studied.展开更多
Used as flame returdant of tunnel asphalt pavement, organic bromides produce a large amount of poisons and smoke in construction and flame retardation stage. The alkaline filler was found to replace mineral filler, ...Used as flame returdant of tunnel asphalt pavement, organic bromides produce a large amount of poisons and smoke in construction and flame retardation stage. The alkaline filler was found to replace mineral filler, and the flame- retarded asphalt mixtures were produced. Experimental results show that these asphalt mixtures are smoke restrained ; the performances and construction technology of asphalt pavement are not influenced; also the alkaline filler is of low-price. So this kind of flame-retarded asphalt mixtures is suitable for tunnel patement.展开更多
Polyurethane (PU) and phenolic (PF) foams used for building isolation were analyzed by thermal gravity/differential thermal analysis to determine their pyrolysis behavior, including the decomposition point and the...Polyurethane (PU) and phenolic (PF) foams used for building isolation were analyzed by thermal gravity/differential thermal analysis to determine their pyrolysis behavior, including the decomposition point and the maximum reaction rate point. Besides, the shape deformations of PU and PF foams were observed, and their oxygen index and the calorific value in combustion were also studied. The results showed that the pyrolysis of both PU and PF can be divided into three stages from room temperature to 1 000 ℃ in the atmospheric air, with total mass loss of 94.345% for PF and 88.191% for PU, respectively. The oxygen index of PU and PF decreased with increasing the temperature and the duration of the heat treatment. With the temperature increasing, the calorific values of both materials were reduced remarkably. These results of the PU and PF could provide basic data of the thermal stability and fire safety design in the application of thermosetting insulation materials.展开更多
The bituminous defect that the binder is flammable will bring road safety risk.Once it catches fires,large quantities of heat,smoke and poisonous gas are produced,released and spread quickly,which seriously hinder esc...The bituminous defect that the binder is flammable will bring road safety risk.Once it catches fires,large quantities of heat,smoke and poisonous gas are produced,released and spread quickly,which seriously hinder escape and rescue and harms heavily traffic safety.The common flame retardant system is used to modify the asphalt.Cone Calorimeter is adopted to evaluate the burning property of asphalt.The performance of the flame retardant is evaluated by limiting oxygen index and orthogonal design method.The paper analyzes the synergism of the asphalt and flame-retardant,and analyzes the effect of the flame on preventing the smoke to spread and demonstrates that the use of common flame retardants which is added into binder is good at reducing the flammability of the binder.This way can increase the safety of asphalt pavement when fire occurs in the tunnel.The study suggests that flame retardancy of asphalt can be evaluated by Limit Oxygen Index (LOI) and the flame retardancy property of asphalt has marked change according to the content of flame retardant.SB has perfect flame retardancy property,and ATH is better than MH in the effect of flame retardant.展开更多
Background:One-lung ventilation (OLV) is a common ventilation technology during thoracic surgery that can cause serious clinical problems.We aimed to conduct a meta-analysis to compare oxygenation and intrapulmonar...Background:One-lung ventilation (OLV) is a common ventilation technology during thoracic surgery that can cause serious clinical problems.We aimed to conduct a meta-analysis to compare oxygenation and intrapulmonary shunt during OLV in adults undergoing thoracic surgery with dexmedetomidine (Dex) versus placebo to assess the influence and safety of using Dex.Methods:Randomized controlled trials comparing lung protection in patients who underwent thoracic surgery with Dex or a placebo were retrieved from PubMed,EMBASE,MEDLINE,Cochrane Library,and China CNKI database.The following information was extracted from the paper:arterial oxygen partial pressure (PaO2),PaO2/inspired oxygen concentration (PaO2/FiO2,oxygenation index [OI]),intrapulmonary shunt (calculated as Qs/Qt),mean arterial pressure (MAP),heart rate (HR),tumor necrosis factor-α (TNF-α),interleukin (IL)-6,superoxide dismutase (SOD),and malondialdehyde (MDA).Results:Fourteen randomized controlled trials were included containing a total of 625 patients.Compared with placebo group,Dex significantly increased PaO2/FiO2 (standard mean difference [SMD] =0.98,95% confidence interval [CI] [0.72,1.23],P 〈 0.00001).Besides,Qs/Qt (SMD=-1.22,95% CI [-2.20,-0.23],P =0.020),HR (SMD=-0.69,95% CI [-1.20,0.17],P =0.009),MAP (SMD=-0.44,95% CI [-0.84,0.04],P =0.030),the concentrations ofTNF-α (SMD =-1.55,95% CI [-2.16,-0.95],P 〈0.001),and IL-6 (SMD =-1.53,95% CI [-2.37,-0.70],P =0.0003) were decreased in the treated group,when compared to placebo group.No significant difference was found in MDA (SMD =-1.14,95% CI [-3.48,1.20],P =0.340) and SOD (SMD =0.41,95% CI [-0.29,1.10],P =0.250) between the Dex group and the placebo group.Funnel plots did not detect any significant publication bias.Conclusions:Dex may improve OI and reduce intrapulmonary shunt during OLV in adults undergoing thoracic surgery.However,this conclusion might be weakened by the limited number of pooled studies and patients.展开更多
The novel benzoxazine monomer containing phosphorus has been synthesized based on multifianctional amine route from bis(4-aminophenyl)phenylphosphate, p-cresol and formaldehyde. Subsequently, the benzoxazine monomer...The novel benzoxazine monomer containing phosphorus has been synthesized based on multifianctional amine route from bis(4-aminophenyl)phenylphosphate, p-cresol and formaldehyde. Subsequently, the benzoxazine monomer was thermo-cured into polybenzoxazine containing phosphorus. The chemical structures were identified by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR). The curing reaction was monitored by differential scanning calorimetry (DSC) and FT-IR. The thermal and flame-retardant properties of obtained polybenzoxazine were evaluated by dynamic mechanical thermal analysis (DMA), thermal gravimetric analysis (TGA) and oxygen index meter, respectively. The results show that the novel polybenzoxazine has high limiting oxygen index (38.1) and glass transition temperature (232℃).展开更多
Six new optically active and flame-retardant poly(amide-imide)s PAls 5a-5f containing phosphine oxide moiety as a flame-retardant unit in the main chain were synthesized from direct polycondensation reaction of six ...Six new optically active and flame-retardant poly(amide-imide)s PAls 5a-5f containing phosphine oxide moiety as a flame-retardant unit in the main chain were synthesized from direct polycondensation reaction of six chiral N,N'-(pyromellitoyl)-bis-L-amino acid 3a-3f with bis(3-aminophenyl)phenyl phosphine oxide 4 in a medium consisting of N-methyl-2-pyrrolidone (NMP), triphenyl phosphite (TPP), calcium chloride (CaCl2) and pyridine. The polymerization reactions produced a series of optically active poly(amide-imide)s with good yield and good inherent viscosity of 0.34-0.70 dLg^-1. The resulted polymers were fully characterized by means of FTIR and ^1H-NMR spectroscopy, gel permeation chromatography (GPC), elemental analyses, inherent viscosity and solubility tests. Thermal properties and flameretardant behavior of the PAIs 5a-5f were investigated using thermal gravimetric analysis (TGA and DTG) and limiting oxygen index (LOI). Data obtained by thermal analysis (TGA and DTG) revealed that these polymers showed good thermal stability. Furthermore, high char yield in TGA and good LOI values indicated that the resulting polymers were capable of exhibiting good flame retardant properties. N,N'-(pyromellitoyl)-bis-L-amino acids 3a-3f were prepared in quantitative yields by the condensation reaction of pyromellitic dianhydride (1,2,4,5-benzenetetracarboxylicacid-1,2,4,5-dianhydride) 1 with L-alanine 2a, L-valine 2b, L-leucine 2c, L-isoleucine 2d, L-phenyl alanine 2e and L-2-aminobutyric acid 2f in acetic acid solution.展开更多
Ecological assessment plays a vital role in sustainable development of the environment,and thus exploration of specific and integrated ecological assessment methods has become a critical task.In this study,based on th...Ecological assessment plays a vital role in sustainable development of the environment,and thus exploration of specific and integrated ecological assessment methods has become a critical task.In this study,based on the concept of oxygen balance and by accommodating both natural factors and socioeconomic elements,we establish an oxygen(O_(2))balance index(OBI),i.e.,the ratio of the O_(2)production from the ecosystem to the O_(2)consumption by human behavior,based on the net primary productivity(NPP),fuel consumption,gross domestic production(GDP),population data,and so on.The results show that the spatial distributions of OBI in China are intimately correlated to the regional vegetation and socioeconomic development.The estimated OBI values are then validated by statistical data from 27 counties in China,and it is found that the OBI reflects the ecological environment status well.Moreover,the average OBI values derived from 190 natural oxygen bars in China reveal extreme imbalance between O_(2)production and consumption in highly developed regions,especially in the cities,in contrast to good O_(2)balance in areas with high-quality ecological status and less industrialization.The findings from this study have quantitatively captured the regional ecological quality,providing guidance for sustainable natural and socioeconomic developments in local areas of China.展开更多
基金Guizhou Provincial Science and Technology Department,Technology Achievement Application and Industrialization Plan,Applied Fundamental Research,No.Qianke Synthetic Fruit[2022]004.
文摘BACKGROUND Accurate condition assessment is critical for improving the prognosis of neonatal respiratory distress syndrome(RDS),but current assessment methods for RDS pose a cumulative risk of harm to neonates.Thus,a less harmful method for assessing the health of neonates with RDS is needed.AIM To analyze the relationships between pulmonary ultrasonography and respiratory distress scores,oxygenation index,and chest X-ray grade of neonatal RDS to identify predictors of neonatal RDS severity.METHODS This retrospective study analyzed the medical information of 73 neonates with RDS admitted to the neonatal intensive care unit of Liupanshui Maternal and Child Care Service Center between April and December 2022.The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest Xray grade of each newborn before and after treatment were collected.Spearman correlation analysis was performed to determine the relationships among these values and neonatal RDS severity.RESULTS The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest X-ray RDS grade of the neonates were significantly lower after treatment than before treatment(P<0.05).Spearman correlation analysis showed that before and after treatment,the pulmonary ultrasonography score of neonates with RDS was positively correlated with the respiratory distress score,oxygenation index,and chest X-ray grade(ρ=0.429–0.859,P<0.05).Receiver operating characteristic curve analysis indicated that pulmonary ultrasonography screening effectively predicted the severity of neonatal RDS(area under the curve=0.805–1.000,P<0.05).CONCLUSION The pulmonary ultrasonography score was significantly associated with the neonatal RDS score,oxygenation index,and chest X-ray grade.The pulmonary ultrasonography score was an effective predictor of neonatal RDS severity.
文摘<strong>Objective:</strong> Coronavirus disease 2019 (COVID-19) spread throughout the world and caused hundreds of thousands of infected people to death. However, the pathogenesis of severe acute respiratory syndrome coronavirus-2 (SARS COV-2) is poorly understood. The objective of this study is to retrospectively explore the pathogenesis of COVID-19 from clinical laboratory findings, taking disease progression into account. <strong>Methods:</strong> A single-centered, retrospective study was carried out, which included moderate (n = 76) and severe COVID-19 cases (n = 22). The difference of laboratory findings from blood routine examination and hepatorenal function test were retrospectively evaluated between the state of moderate and severe. The disease progression was indicated by oxygenation index. <strong>Results: </strong>Age is a risk factor for disease progression from moderate to severe. Lymphocytopenia, neutrophilia, liver and kidney function decreasement occurred in severe patients on admission, compared with moderate patients. Lymphocytopenia and neutrophilia deteriorated at the lowest oxygenation index timepoint in the severe patients. And the oxygenation index was associated with ratio of lymphocyte and neutrophil in COVID-19 patients. <strong>Conclusions:</strong> Lymphocytopenia and neutrophilia, which deteriorate in the progression of severe patients, are the main pathogenesis of COVID-19. More measures need to be taken to control lymphocytopenia and neutrophilia in severe COVID-19. Oxygenation index presented potentiality as predictor on the progression of COVID-19.
文摘BACKGROUND:Animal experiments showed that recruitment maneuver (RM) and protective ventilation strategy of the lung could improve oxygenation and reduce extravascular lung water. This study was to investigate the effects of RM on respiratory mechanics and extravascular lung water index (EVLWI) in patients with acute respiratory distress syndrome (ARDS). METHODS:Thirty patients with ARDS were randomized into a RM group and a non-RM group. In the RM group, after basic mechanical ventilation stabilized for 30 minutes, RM was performed and repeated once every 12 hours for 3 days. In the non-RM group, lung protective strategy was conducted without RM. Oxygenation index (PaO2/FiO2), peak inspiratory pressure (PIP), Plateau pressure (Pplat), static pulmonary compliance (Cst) and EVLWI of patients before treatment and at 12, 24, 48, 72 hours after the treatment were measured and compared between the groups. Hemodynamic changes were observed before and after RM. One-way ANOVA, Student's t test and Fisher's exact test were used to process the data. RESULTS:The levels of PaO2/FiO2 and Cst increased after treatment in the two groups, but they were higher in the RM group than in the non-RM group (P〈0.05). The PIP and Pplat decreased after treatment in the two groups, but they were lower in the RM group than in the non-RM group (P〈0.05). The EVLWI in the two groups showed downward trend after treatment (P〈0.05), and the differences were signifcant at all time points (P〈0.01); the EVLWI in the RM group was lower than that in the non-RM group at 12, 24, 48 and 72 hours (P〈0.05 or P〈0.01). Compared with pre-RM, hemodynamics changes during RM were significantly different (P〈0.01); compared with pre-RM, the changes were not significantly different at 120 seconds after the end of RM (P〉0.05). CONCLUSIONS: RM could reduce EVLWI, increase oxygenation and lung compliance. The effect of RM on hemodynamics was transient.
文摘Biochemical, anatomical, and physiological characteristics of the brain make it especially vulnerable to insult. Specifically, some of these characteristics such as myelin and a high energy requirement provide for the introduction of free radical-induced insult. Recently, the biochemistry of free radicals has received considerable attention. It also has become increasingly suggestive that many drug and chemical-induced toxicities may be evoked via free radicals and oxidative stress. Major points addressed in this work are the regulation of neural-free radical generation by antioxidants and protective enzymes, xenobiotic-induced disruption of cerebral redox status, and specific examples of neurotoxic agent-induced alterations in free radicals as measured by the fluorescent probe dichlorofluorescein. This article considers that free radical mechanisms may contribute significantly to the properties of several diverse neurotoxic agents and proposes that free radicals may be common phenomena of neurotoxicity.
基金This study was supported by a grant from the Natural Science Foundation of Shandong Province (Y2006C77).
文摘BACKGROUND:High-volume hemofiltration (HVHF) is technically possible in severe acute pancreatitis (SAP) patients complicated with multiple organ dysfunction syndrome (MODS). Continuous HVHF is expected to become a beneficial adjunct therapy for SAP complicated with MODS. In this study, we aimed to explore the effects of fluid resuscitation and HVHF on alveolar- arterial oxygen exchange, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score in patients with refractory septic shock. METHODS:A total of 89 refractory septic shock patients, who were admitted to ICU, the Provincial Hospital affiliated to Shandong University from August 2006 to December 2009, were enrolled in this retrospective study. The patients were randomly divided into two groups: fluid resuscitation (group A, n=41), and fluid resuscitation plus high-volume hemofiltration (group B, n=48), The levels of O2 content of central venous blood (CcvO2), arterial oxygen content (CaO2), alveolar-arterial oxygen pressure difference P(A-a)DO2, ratio of arterial oxygen pressure/alveolar oxygen pressure (PaO2/ PAO2), respiratory index (RI) and oxygenation index (OI) were determined. The oxygen exchange levels of the two groups were examined based on the arterial blood gas analysis at different times (0, 24, 72 hours and 7 days of treatment) in the two groups. The APACHE II score was calculated before and after 7-day treatment in the two groups. The levels of CcvO2, CaO2 on day 7 in group A were significantly lower than those in group B (CcvO2:0.60±0.24 vs, 0.72±0.28, P〈0.05; CaO2:0.84±0.43 vs. 0.94±0.46, P〈0.05). The level of oxygen extraction rate (O2ER) in group A on the 7th day was significantly higher than that in group B ( 28.7±2.4 vs. 21.7±3.4, P〈0.01). The levels of P(A-a)DO2 and RI in group B on the 7th day were significantly lower than those in group A. The levels of PaO2/PAO2 and OI in group B on 7th day were significantly higher than those in group A (P〈0.05 or P〈0.01). The APACHE II score in the two groups reduced gradually after 7-day treatment, and the APACHE II score on the 7th day in group B was significantly lower than that in group A (8.2±3.8 vs. 17.2±6.8, P〈0.01). HVHF combined with fluid resuscitation can improve alveolar- arterial-oxygen exchange, decrease the APACHE II score in patients with refractory septic shock, and thus it increases the survival rate of patients.
基金Supported by the Chongqing Medical Scientific Research Project(Joint Project of Chongqing Health Commission and Science and Technology Bureau),No.2020FYYX163Chongqing Medical Key Discipline Construction Project,No.ZDXK202103Fundamental Research Funds for the Central Universities and Advanced Middle-Aged and Young Medical Talents Project in Chongqing,No.2022CDJYGRH-014。
文摘BACKGROUND Aortic dissection is a complex and dangerous cardiovascular disease,with many complications in the perioperative period,including severe acute respiratory distress syndrome(ARDS),which affects prognosis and increases mortality.Despite the effect of prone positioning(PP)in improving oxygenation in patients with severe ARDS,reports about PP early after cardiac surgery are few and such an opt-ion may be an issue in cardiac surgery patients because of the recent sternotomy.CASE SUMMARY A 40-year-old male patient diagnosed with acute type A aortic dissection on October 22,2021 underwent ascending artery replacement plus total aortic arch replacement plus stent elephant trunk implantation under cardiopulmonary bypass.Unfortunately,he developed ARDS on postoperative day 1.Despite comprehensive treatment with aggressive pulmonary protective ventilation,fluid management with continuous renal replacement therapy,the condition continued to deteriorate and rapidly progressed to severe ARDS with a minimum oxygenation index of 51.We are ready to implement salvage therapy,including PP and extracorporeal membrane oxygenation(ECMO).Due to the large amount of pericardial mediastinal and thoracic drainage after thoracotomy,ECMO may result in massive postoperative bleeding.Prolonged prone ventilation is often inappropriate after thoracotomy.Therefore,we chose short-term PP for<6 h.Finally,the oxygenation index greatly improved and the diffuse exudation in both lungs of the patient was significantly reduced with short-term prone positioning.CONCLUSION Intermittent short-term PP can improve early postoperative severe ARDS after acute aortic dissection.
文摘[Objectives]To systematically evaluate the effects of early-stage phased rehabilitation training on the oxygenation index,ICU length of stay,duration of mechanical ventilation,and occurrence of complications(ventilator-associated pneumonia,pressure ulcers,delirium)in ARDS patients,thus contributing evidence for the clinical application of early-stage phased rehabilitation training.[Methods]The China National Knowledge Infrastructure(CNKI),Wanfang,and other databases were searched.Literature screening,data extraction,and systematic analysis of the included studies were performed using Revman software.[Results]Thirteen randomized controlled trials involving a total of 860 patients were included in this review.The results of the meta-analysis showed that compared to the traditional rehabilitation training group,the early-stage phased rehabilitation training group demonstrated a significant increase in the oxygenation index of ARDS patients[SMD=1.18,95%CI(1.01,1.35),P<0.01],with statistically significant differences.Furthermore,there were significant reductions in ICU length of stay[SMD=-0.70,95%CI(-0.90,-0.50),P<0.01],duration of mechanical ventilation[SMD=-1.15,95%CI(-1.36,-0.94),P<0.01],and occurrence of complications[OR=0.16,95%CI(0.10,0.26),P<0.01],all of which were statistically significant.[Conclusions]Early-stage phased pulmonary rehabilitation training for ARDS patients effectively improves the oxygenation index,shortens ICU length of stay and duration of mechanical ventilation,and reduces complications.These findings support the clinical application and promotion of early-stage phased rehabilitation training.
文摘The article provides information on our achievements in the application of modern diagnostic methods and modern methods of treating patients with viral pneumonia,confirmed by covid-19.For this,statistical data of 2,000 patients were used.Of the 2,000 patients treated,920 were men,1,070 were women and 10 were children.Viral pneumonia-glaucoma syndrome in 1650 out of 2,000 patients with 10-20%damage;In 350,the diagnosis of viral pneumonia-frostbite syndrome with 50-85%damage,CRDS,respiratory failure was confirmed.Thus,50 out of 350 patients treated at the intensive care unit(ICU)out of 2,000 were intubated and connected to artificial ventilation.The research was carried out in 3 stages:I stage-admission to the intensive care unit;II stage-from the day of intubation to spontaneous breathing(7-14 days);and III stage-covers the period of extubation and recovery.The results of clinical,functional,hemodynamic and echocardiographic studies of the patients participating in the examination were analyzed.Also,the patients underwent bacteriological research studied the sensitivity to antibiotics.In addition,the composition of blood gases and the oxygenation index-Carrico were studied.
文摘Used as flame returdant of tunnel asphalt pavement, organic bromides produce a large amount of poisons and smoke in construction and flame retardation stage. The alkaline filler was found to replace mineral filler, and the flame- retarded asphalt mixtures were produced. Experimental results show that these asphalt mixtures are smoke restrained ; the performances and construction technology of asphalt pavement are not influenced; also the alkaline filler is of low-price. So this kind of flame-retarded asphalt mixtures is suitable for tunnel patement.
文摘Polyurethane (PU) and phenolic (PF) foams used for building isolation were analyzed by thermal gravity/differential thermal analysis to determine their pyrolysis behavior, including the decomposition point and the maximum reaction rate point. Besides, the shape deformations of PU and PF foams were observed, and their oxygen index and the calorific value in combustion were also studied. The results showed that the pyrolysis of both PU and PF can be divided into three stages from room temperature to 1 000 ℃ in the atmospheric air, with total mass loss of 94.345% for PF and 88.191% for PU, respectively. The oxygen index of PU and PF decreased with increasing the temperature and the duration of the heat treatment. With the temperature increasing, the calorific values of both materials were reduced remarkably. These results of the PU and PF could provide basic data of the thermal stability and fire safety design in the application of thermosetting insulation materials.
基金Sponsored by the National Natural Science Foundation of China (Grant No. 50078057)Program for New Century Excellent Talents in University(Grant No. NCET-06-0340)
文摘The bituminous defect that the binder is flammable will bring road safety risk.Once it catches fires,large quantities of heat,smoke and poisonous gas are produced,released and spread quickly,which seriously hinder escape and rescue and harms heavily traffic safety.The common flame retardant system is used to modify the asphalt.Cone Calorimeter is adopted to evaluate the burning property of asphalt.The performance of the flame retardant is evaluated by limiting oxygen index and orthogonal design method.The paper analyzes the synergism of the asphalt and flame-retardant,and analyzes the effect of the flame on preventing the smoke to spread and demonstrates that the use of common flame retardants which is added into binder is good at reducing the flammability of the binder.This way can increase the safety of asphalt pavement when fire occurs in the tunnel.The study suggests that flame retardancy of asphalt can be evaluated by Limit Oxygen Index (LOI) and the flame retardancy property of asphalt has marked change according to the content of flame retardant.SB has perfect flame retardancy property,and ATH is better than MH in the effect of flame retardant.
文摘Background:One-lung ventilation (OLV) is a common ventilation technology during thoracic surgery that can cause serious clinical problems.We aimed to conduct a meta-analysis to compare oxygenation and intrapulmonary shunt during OLV in adults undergoing thoracic surgery with dexmedetomidine (Dex) versus placebo to assess the influence and safety of using Dex.Methods:Randomized controlled trials comparing lung protection in patients who underwent thoracic surgery with Dex or a placebo were retrieved from PubMed,EMBASE,MEDLINE,Cochrane Library,and China CNKI database.The following information was extracted from the paper:arterial oxygen partial pressure (PaO2),PaO2/inspired oxygen concentration (PaO2/FiO2,oxygenation index [OI]),intrapulmonary shunt (calculated as Qs/Qt),mean arterial pressure (MAP),heart rate (HR),tumor necrosis factor-α (TNF-α),interleukin (IL)-6,superoxide dismutase (SOD),and malondialdehyde (MDA).Results:Fourteen randomized controlled trials were included containing a total of 625 patients.Compared with placebo group,Dex significantly increased PaO2/FiO2 (standard mean difference [SMD] =0.98,95% confidence interval [CI] [0.72,1.23],P 〈 0.00001).Besides,Qs/Qt (SMD=-1.22,95% CI [-2.20,-0.23],P =0.020),HR (SMD=-0.69,95% CI [-1.20,0.17],P =0.009),MAP (SMD=-0.44,95% CI [-0.84,0.04],P =0.030),the concentrations ofTNF-α (SMD =-1.55,95% CI [-2.16,-0.95],P 〈0.001),and IL-6 (SMD =-1.53,95% CI [-2.37,-0.70],P =0.0003) were decreased in the treated group,when compared to placebo group.No significant difference was found in MDA (SMD =-1.14,95% CI [-3.48,1.20],P =0.340) and SOD (SMD =0.41,95% CI [-0.29,1.10],P =0.250) between the Dex group and the placebo group.Funnel plots did not detect any significant publication bias.Conclusions:Dex may improve OI and reduce intrapulmonary shunt during OLV in adults undergoing thoracic surgery.However,this conclusion might be weakened by the limited number of pooled studies and patients.
基金financially SUpponed by the National Natural Science Foundation of ChiNa(No.21074067)the Natural Science FOUNdation of Shandong Province(No.Y2008804)
文摘The novel benzoxazine monomer containing phosphorus has been synthesized based on multifianctional amine route from bis(4-aminophenyl)phenylphosphate, p-cresol and formaldehyde. Subsequently, the benzoxazine monomer was thermo-cured into polybenzoxazine containing phosphorus. The chemical structures were identified by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR). The curing reaction was monitored by differential scanning calorimetry (DSC) and FT-IR. The thermal and flame-retardant properties of obtained polybenzoxazine were evaluated by dynamic mechanical thermal analysis (DMA), thermal gravimetric analysis (TGA) and oxygen index meter, respectively. The results show that the novel polybenzoxazine has high limiting oxygen index (38.1) and glass transition temperature (232℃).
文摘Six new optically active and flame-retardant poly(amide-imide)s PAls 5a-5f containing phosphine oxide moiety as a flame-retardant unit in the main chain were synthesized from direct polycondensation reaction of six chiral N,N'-(pyromellitoyl)-bis-L-amino acid 3a-3f with bis(3-aminophenyl)phenyl phosphine oxide 4 in a medium consisting of N-methyl-2-pyrrolidone (NMP), triphenyl phosphite (TPP), calcium chloride (CaCl2) and pyridine. The polymerization reactions produced a series of optically active poly(amide-imide)s with good yield and good inherent viscosity of 0.34-0.70 dLg^-1. The resulted polymers were fully characterized by means of FTIR and ^1H-NMR spectroscopy, gel permeation chromatography (GPC), elemental analyses, inherent viscosity and solubility tests. Thermal properties and flameretardant behavior of the PAIs 5a-5f were investigated using thermal gravimetric analysis (TGA and DTG) and limiting oxygen index (LOI). Data obtained by thermal analysis (TGA and DTG) revealed that these polymers showed good thermal stability. Furthermore, high char yield in TGA and good LOI values indicated that the resulting polymers were capable of exhibiting good flame retardant properties. N,N'-(pyromellitoyl)-bis-L-amino acids 3a-3f were prepared in quantitative yields by the condensation reaction of pyromellitic dianhydride (1,2,4,5-benzenetetracarboxylicacid-1,2,4,5-dianhydride) 1 with L-alanine 2a, L-valine 2b, L-leucine 2c, L-isoleucine 2d, L-phenyl alanine 2e and L-2-aminobutyric acid 2f in acetic acid solution.
基金Supported by the National Key Research and Development Program of China(2021YFB3901002)GaoFen Project(32-Y30F08-9001-20/22)+1 种基金National Natural Science Foundation of China(41977191)Innovation Fund of Public Meteorological Service Centre,China Meteorological Administration(K2021003).
文摘Ecological assessment plays a vital role in sustainable development of the environment,and thus exploration of specific and integrated ecological assessment methods has become a critical task.In this study,based on the concept of oxygen balance and by accommodating both natural factors and socioeconomic elements,we establish an oxygen(O_(2))balance index(OBI),i.e.,the ratio of the O_(2)production from the ecosystem to the O_(2)consumption by human behavior,based on the net primary productivity(NPP),fuel consumption,gross domestic production(GDP),population data,and so on.The results show that the spatial distributions of OBI in China are intimately correlated to the regional vegetation and socioeconomic development.The estimated OBI values are then validated by statistical data from 27 counties in China,and it is found that the OBI reflects the ecological environment status well.Moreover,the average OBI values derived from 190 natural oxygen bars in China reveal extreme imbalance between O_(2)production and consumption in highly developed regions,especially in the cities,in contrast to good O_(2)balance in areas with high-quality ecological status and less industrialization.The findings from this study have quantitatively captured the regional ecological quality,providing guidance for sustainable natural and socioeconomic developments in local areas of China.