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
Objective:To evaluate the efficacy and safety of protective lung ventilation strategy combined with lung recruitment maneuver (RM) in the treatment patients with acute respiratory distress syndrome (ARDS).Methods:Tota...Objective:To evaluate the efficacy and safety of protective lung ventilation strategy combined with lung recruitment maneuver (RM) in the treatment patients with acute respiratory distress syndrome (ARDS).Methods:Totally 74 patients with ARDS admitted to the Department of Intensive Care Unit, Changshu Second People's Hospital in Jiangsu Province between September 2010 and June 2013 were selected and randomly divided into lung recruitment group and non-lung recruitment group, and the initial ventilation solution for both groups was synchronized intermittent mandatory ventilation (SIMV). For RM, SIMV mode (pressure control and pressure support) was adopted. Positive end expiratory pressure (PEEP) was increased by 5 cm H2O every time and maintained for 40-50 s before entering the next increasing period, and the peak airway pressure was kept below 45 cm H2O. After PEEP reached the maximum value, it was gradually reduced by 5 cm H2O every time and finally maintained at 15 cm H2O for 10 min.Results:A total of 74 patients with mean age of (49.0±18.6) years old were enrolled, 36 patients were enrolled in lung recruitment maneuver (RM) group and 38 patients were enrolled into non-lung recruitment maneuver (non-RM) group. 44 were male and accounted for 59.5% of all the patients. For the indicators such as PEEP, pressure support (PS), plateau airway pressure (Pplat), peak airway pressure (Ppeak), vital capacity (VC) and fraction of inspired oxygen (FiO2), no statistical differences in the indicators were found between the RM group and non-RM group on D1, D3 and D7 (P>0.05), except that only FiO2 of RM group on D7 was significantly lower than that of non-RM group (47.2±10.0) vs. (52.2±10.5),P<0.05]. For the indicators of blood gas analysis, including pH, arterial oxygen pressure (PaO2), arterial carbon dioxide pressure (PaCO2) and oxygenation index (PaO2/FiO2), PaO2 and PaO2/FiO2 of RM group were significantly higher than those of non-RM group on D7, and the values were [(90.2±16.1) mmHg vs. (76.4±11.3) mmHg,P<0.05] and [(196.5±40.7) mmHg vs. (151.7±37.3) mmHg,P<0.05] respectively. There was no statistical difference in heart rate (HR), cardiac index (CI), central venous pressure (CVP) or mean arterial pressure (MAP) between RM group and non-RM group on D1, D3 and D7 (P>0.05). 28-day mortality, ICU mortality and in-hospital mortality were 25% vs. 28.9%, 25% vs. 26.3% and 36.1% vs. 39.5% respectively between RM group and non-RM group (allP>0.05).Conclusion:Protective lung ventilation strategy combined with lung recruitment maneuver can improve the indicators such as PaO2, FiO2 and PaO2/FiO2 on D7, but failed to improve the final outcomes such as 28-day mortality, ICU mortality and in-hospital mortality.展开更多
BACKGROUND: This study aimed to observe the effect of recruitment maneuver (RM) and post-RM ventilation at different tidal volume on lung vascular diastole endothelial function in rats with acute lung injury (ALI...BACKGROUND: This study aimed to observe the effect of recruitment maneuver (RM) and post-RM ventilation at different tidal volume on lung vascular diastole endothelial function in rats with acute lung injury (ALI).METHODS: A ALl rat model was produced by intravenous infusion of lipopolysaccharide (6 mg/ kg). Twenty-five rats were randomly divided into five groups: control group (n=5), ALl group (n=5), low tidal volume group (LV group, VT 6 mL/kg, n=5), sustained inflation (SI) with low tidal volume group (SI+LV group, VT 6 mL/kg, n=5), and SI with moderate tidal volume group (SI+MV group, VT 12 mL/ kg, n=5). RM was performed with SI, airway pressure 30 cmH2O for 30 seconds, and positive end- expiratory pressure (PEEP) was set to 5 cmH2O. Lung tissue was taken after 5 hours of mechanical ventilation. Mean arterial blood pressure (MAP) was monitored during the experiment. Endothelin-1 (ET-1), endothelial nitricoxide synthase (eNOS), Ach-induced endothelium-dependent relaxation response of isolated pulmonary artery rings were determined at 5 hours. RESULTS:LPS increased ET-1 level, decreased the expression of eNOS in lung tissue, impaired the Ach-induced endothelium-dependent relaxation response in the pulmonary artery, without obvious effect on systemic hemodynamics. SI+LV significantly reduced LPS-induced elevation of ET-1 level, increased the expression of eNOS, significantly improved endothelial dysfunction, and improved the dysfunction of endothelium-dependent relaxation in the pulmonary artery. CONCLUSIONS:RM with a high or low tidal volume ventilation could improve the lung vascular endothelial function of rats with acute lung injury, and RM with low tidal volume ventilation could lower significantly the injury of lung vascular endothelial diastole function in rats with acute lung injury.展开更多
Acute respiratory distress syndrome(ARDS) represents a serious problem in critically ill patients and is associated with in-hospital mortality rates of 33%-52%. Recruitment maneuvers(RMs) are a simple, low-cost, feasi...Acute respiratory distress syndrome(ARDS) represents a serious problem in critically ill patients and is associated with in-hospital mortality rates of 33%-52%. Recruitment maneuvers(RMs) are a simple, low-cost, feasible intervention that can be performed at the bedside in patients with ARDS. RMs are characterized by the application of airway pressure to increase transpulmonary pressure transiently. Once non-aerated lung units are reopened, improvements are observed in respiratory system mechanics, alveolar reaeration on computed tomography, and improvements in gas exchange(functional recruitment). However, the reopening process could lead to vascular compression, which can be associated with overinflation, and gas exchange may not improve as expected(anatomical recruitment). The purpose of this review was to discuss the effects of different RM strategies- sustained inflation, intermittent sighs, and stepwise increases of positive end-expiratory pressure(PEEP) and/or airway inspiratory pressure- on the following parameters: hemodynamics, oxygenation, barotrauma episodes, and lung recruitability through physiological variables and imaging techniques. RMs and PEEP titration are interdependent events for the success of ventilatory management. PEEP should be adjusted on the basis of respiratory system mechanics and oxygenation. Recent systematic reviews and meta-analyses suggest that RMs are associated with lower mortality in patients with ARDS. However, the optimal RM method(i.e., that providing the best balance of benefit and harm) and the effects of RMs on clinical outcome are still under discussion, and further evidence is needed.展开更多
目的 探讨肺复张治疗急性A型主动脉夹层(acute type A aortic dissection,ATAAD)术后低氧血症的疗效及安全性。方法 选取2019年11月至2022年5月广西医科大学第一附属医院ATAAD术后低氧血症患者56例,将其随机分为肺复张组(n=36)及常规治...目的 探讨肺复张治疗急性A型主动脉夹层(acute type A aortic dissection,ATAAD)术后低氧血症的疗效及安全性。方法 选取2019年11月至2022年5月广西医科大学第一附属医院ATAAD术后低氧血症患者56例,将其随机分为肺复张组(n=36)及常规治疗组(n=20)。常规治疗组患者在肺保护性通气基础上行常规机械通气,肺复张组患者采用呼气末正压通气(positive end expiratory pressure,PEEP)递增法进行肺复张。比较两组患者治疗前后的动脉血气分析、呼吸力学指标、血流动力学指标和血清白细胞介素(interleukin,IL)-6及IL-10水平。结果 治疗后12h、24h,两组患者的动脉血氧分压(arterial partial pressure of oxygen,PaO_(2))、氧合指数(oxygenation index,OI)、肺静态顺应性(C_(stat))及肺动态顺应性(C_(dyn))均显著高于本组治疗前,肺泡动脉氧分压差[PO_(2)(A-a)]、呼吸指数(respiratory index,RI)、气道峰压(P_(peak))及气道平台压(P_(plat))均显著低于本组治疗前(P<0.05);肺复张组患者的PaO_(2)、OI、C_(stat)及C_(dyn)均显著高于常规治疗组,PO_(2)(A-a)、RI、P_(peak)及P_(plat)均显著低于常规治疗组(P<0.05)。肺复张组患者肺复张过程中收缩压及平均动脉压有所下降(P<0.05),中心静脉压有所升高(P<0.05),肺复张结束后均恢复至基线水平。治疗后12h,两组患者的血清IL-6和IL-10水平均显著低于本组治疗前(P<0.05)。结论 PEEP递增法肺复张可改善ATAAD术后低氧血症患者的氧合及肺顺应性,但对血流动力学存在一过性影响,治疗时应进行严密监测。展开更多
Background It is still controversial as to the implementation of higher positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS). This study was conducted to compare the ...Background It is still controversial as to the implementation of higher positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS). This study was conducted to compare the lower and higher PEEP in patients with ARDS ventilated with low tidal volume, to investigate the relationship between the recruited lung volume by higher PEEP and relevant independent variables and to provide a bedside estimate of the percentage of potentially recruitable lung by higher PEEP. Methods Twenty-four patients with ARDS were studied. A lung recruiting maneuver was performed, then each patient was ventilated with PEEP of 8 cmH20 for 4 hours and subsequently with PEEP of 16 cmH20 for 4 hours. At the end of each PEEP level period, gas exchange, hemodynamic data, lung mechanics, stress index "b" of the dynamic pressure-time curve, intrinsic PEEP and recruited volume by PEEP were measured. Results Fourteen patients were recruiters whose alveolar recruited volumes induced by PEEP 16 cmH20 were (425_+65) ml and 10 patients were non-recruiters. Compared with the PEEP 8 cmH20 period, after the application of the PEEP 16 cmH20, the PaO2/FiO2 ratio and static lung compliance both remained unchanged in non-recruiters, whereas they increased significantly in recruiters. Changes in PaO2/FiO2 and static lung compliance after PEEP increase were independently associated with the alveolar recruitment. Analyzing the relationship between recruiting maneuver (RM)-induced change in end-expiratory lung volume and the alveolar recruitment induced by PEEP, we found a notable correlation. Conclusions The results of this study indicated that the potential for alveolar recruitment might vary among the ARDS population and the higher PEEP levels should be limited to recruiters. Improving in PaO2/FiO2, static lung compliance after PEEP increase and the shape of the pressure-time curve could be helpful for PEEP application.展开更多
肺脏肿瘤是一种高发病率、高致死率疾病[1],在发展早期主要依赖NK细胞等淋巴细胞发挥抗肿瘤作用[2],其中CXCR3^(+)NK细胞可依赖CXCL9/10等趋化因子的招募作用[3]而快速迁移,并大量分泌IFN-γ和穿孔素等效应因子,发挥免疫监视等作用[4]...肺脏肿瘤是一种高发病率、高致死率疾病[1],在发展早期主要依赖NK细胞等淋巴细胞发挥抗肿瘤作用[2],其中CXCR3^(+)NK细胞可依赖CXCL9/10等趋化因子的招募作用[3]而快速迁移,并大量分泌IFN-γ和穿孔素等效应因子,发挥免疫监视等作用[4]。桔梗-姜半夏配伍(the combination of Platycodon Grandiflorum and Pinella Ternata,PG+PT)常用于肿瘤的临床治疗中[5]。本研究旨在探讨PG+PT对肺脏肿瘤微环境中NK细胞、特别是CXCR3+NK的免疫药理作用,以明确该配伍发挥抗肿瘤作用的部分药理机制。展开更多
Background:Coronavirus disease 2019(COVID-19)has been frequently complicated by severe acute respiratory distress syndrome(ARDS)with prolonged invasive ventilation.While respiratory system compliance and lung recruita...Background:Coronavirus disease 2019(COVID-19)has been frequently complicated by severe acute respiratory distress syndrome(ARDS)with prolonged invasive ventilation.While respiratory system compliance and lung recruitability have been described within the first days after ICU admission,data about their longitudinal changes are still limited.Therefore,we conducted this study to assess the evolution of respiratory system compliance and lung recruitability in patients with COVID-19–related ARDS.Method:We conducted a prospective single-center study in patients admitted for COVID-19–related ARDS during the first wave of the pandemic,from March 16,2020 to April 10,2020.Respiratory system compliance was calculated daily at clinical positive end-expiratory pressure(PEEP)during passive breathing.The potential for lung recruitment was assessed by measuring the volume derecruited between PEEP 15 cmH2 O and 5 cmH2 O,and using the calculation of the recruitment-to-inflation ratio(R/I ratio).Recruitable lung was considered when the R/I ratio was at least 0.5.The primary outcome was the evolution of respiratory mechanics over time.The secondary outcome was the evolution of lung recruitability over time.Results:Thirty-two patients were included in this study.The respiratory mechanics were assessed 222 times(7±5 times per patient).Respiratory system compliance at clinical PEEP was 29.1 mL/cmH2 O(interquartile range[IQR]:24.1–33.9 mL/cmH2 O)and decreased significantly over time(P<0.0001).Lung recruitability was assessed in 22 out of the 32 patients(60 assessments).The median volume derecruited between PEEP 15 cmH2 O and 5 cmH2 O was 246.8 mL(IQR:180.8–352.2 mL)and the median R/I ratio was 0.56(IQR:0.39–0.73).Neither changed significantly over time.The proportion of patients with recruitable lung was 50.0%(6/12)within the first 3 days after intubation,69.2%(9/13)between day 4 and day 7,and 66.7%(8/12)after day 7(P=0.7934).Conclusions:In our cohort,respiratory system compliance was low and decreased over time.The potential for lung recruitment was high and persisted despite prolonged mechanical ventilation,suggesting that maintaining high PEEP levels in the later course of COVID-19 could be adequate.展开更多
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Objective:To evaluate the efficacy and safety of protective lung ventilation strategy combined with lung recruitment maneuver (RM) in the treatment patients with acute respiratory distress syndrome (ARDS).Methods:Totally 74 patients with ARDS admitted to the Department of Intensive Care Unit, Changshu Second People's Hospital in Jiangsu Province between September 2010 and June 2013 were selected and randomly divided into lung recruitment group and non-lung recruitment group, and the initial ventilation solution for both groups was synchronized intermittent mandatory ventilation (SIMV). For RM, SIMV mode (pressure control and pressure support) was adopted. Positive end expiratory pressure (PEEP) was increased by 5 cm H2O every time and maintained for 40-50 s before entering the next increasing period, and the peak airway pressure was kept below 45 cm H2O. After PEEP reached the maximum value, it was gradually reduced by 5 cm H2O every time and finally maintained at 15 cm H2O for 10 min.Results:A total of 74 patients with mean age of (49.0±18.6) years old were enrolled, 36 patients were enrolled in lung recruitment maneuver (RM) group and 38 patients were enrolled into non-lung recruitment maneuver (non-RM) group. 44 were male and accounted for 59.5% of all the patients. For the indicators such as PEEP, pressure support (PS), plateau airway pressure (Pplat), peak airway pressure (Ppeak), vital capacity (VC) and fraction of inspired oxygen (FiO2), no statistical differences in the indicators were found between the RM group and non-RM group on D1, D3 and D7 (P>0.05), except that only FiO2 of RM group on D7 was significantly lower than that of non-RM group (47.2±10.0) vs. (52.2±10.5),P<0.05]. For the indicators of blood gas analysis, including pH, arterial oxygen pressure (PaO2), arterial carbon dioxide pressure (PaCO2) and oxygenation index (PaO2/FiO2), PaO2 and PaO2/FiO2 of RM group were significantly higher than those of non-RM group on D7, and the values were [(90.2±16.1) mmHg vs. (76.4±11.3) mmHg,P<0.05] and [(196.5±40.7) mmHg vs. (151.7±37.3) mmHg,P<0.05] respectively. There was no statistical difference in heart rate (HR), cardiac index (CI), central venous pressure (CVP) or mean arterial pressure (MAP) between RM group and non-RM group on D1, D3 and D7 (P>0.05). 28-day mortality, ICU mortality and in-hospital mortality were 25% vs. 28.9%, 25% vs. 26.3% and 36.1% vs. 39.5% respectively between RM group and non-RM group (allP>0.05).Conclusion:Protective lung ventilation strategy combined with lung recruitment maneuver can improve the indicators such as PaO2, FiO2 and PaO2/FiO2 on D7, but failed to improve the final outcomes such as 28-day mortality, ICU mortality and in-hospital mortality.
文摘BACKGROUND: This study aimed to observe the effect of recruitment maneuver (RM) and post-RM ventilation at different tidal volume on lung vascular diastole endothelial function in rats with acute lung injury (ALI).METHODS: A ALl rat model was produced by intravenous infusion of lipopolysaccharide (6 mg/ kg). Twenty-five rats were randomly divided into five groups: control group (n=5), ALl group (n=5), low tidal volume group (LV group, VT 6 mL/kg, n=5), sustained inflation (SI) with low tidal volume group (SI+LV group, VT 6 mL/kg, n=5), and SI with moderate tidal volume group (SI+MV group, VT 12 mL/ kg, n=5). RM was performed with SI, airway pressure 30 cmH2O for 30 seconds, and positive end- expiratory pressure (PEEP) was set to 5 cmH2O. Lung tissue was taken after 5 hours of mechanical ventilation. Mean arterial blood pressure (MAP) was monitored during the experiment. Endothelin-1 (ET-1), endothelial nitricoxide synthase (eNOS), Ach-induced endothelium-dependent relaxation response of isolated pulmonary artery rings were determined at 5 hours. RESULTS:LPS increased ET-1 level, decreased the expression of eNOS in lung tissue, impaired the Ach-induced endothelium-dependent relaxation response in the pulmonary artery, without obvious effect on systemic hemodynamics. SI+LV significantly reduced LPS-induced elevation of ET-1 level, increased the expression of eNOS, significantly improved endothelial dysfunction, and improved the dysfunction of endothelium-dependent relaxation in the pulmonary artery. CONCLUSIONS:RM with a high or low tidal volume ventilation could improve the lung vascular endothelial function of rats with acute lung injury, and RM with low tidal volume ventilation could lower significantly the injury of lung vascular endothelial diastole function in rats with acute lung injury.
基金Supported by Brazilian Council for Scientific and Technological Development(CNPq),Carlos Chagas Filho Rio de Janeiro State Research Foundation(FAPERJ),Department of Science and Technology(DECIT)/Brazilian Ministry of HealthCoordination for the Improvement of Higher Level Personnel(CAPES)
文摘Acute respiratory distress syndrome(ARDS) represents a serious problem in critically ill patients and is associated with in-hospital mortality rates of 33%-52%. Recruitment maneuvers(RMs) are a simple, low-cost, feasible intervention that can be performed at the bedside in patients with ARDS. RMs are characterized by the application of airway pressure to increase transpulmonary pressure transiently. Once non-aerated lung units are reopened, improvements are observed in respiratory system mechanics, alveolar reaeration on computed tomography, and improvements in gas exchange(functional recruitment). However, the reopening process could lead to vascular compression, which can be associated with overinflation, and gas exchange may not improve as expected(anatomical recruitment). The purpose of this review was to discuss the effects of different RM strategies- sustained inflation, intermittent sighs, and stepwise increases of positive end-expiratory pressure(PEEP) and/or airway inspiratory pressure- on the following parameters: hemodynamics, oxygenation, barotrauma episodes, and lung recruitability through physiological variables and imaging techniques. RMs and PEEP titration are interdependent events for the success of ventilatory management. PEEP should be adjusted on the basis of respiratory system mechanics and oxygenation. Recent systematic reviews and meta-analyses suggest that RMs are associated with lower mortality in patients with ARDS. However, the optimal RM method(i.e., that providing the best balance of benefit and harm) and the effects of RMs on clinical outcome are still under discussion, and further evidence is needed.
文摘目的 探讨肺复张治疗急性A型主动脉夹层(acute type A aortic dissection,ATAAD)术后低氧血症的疗效及安全性。方法 选取2019年11月至2022年5月广西医科大学第一附属医院ATAAD术后低氧血症患者56例,将其随机分为肺复张组(n=36)及常规治疗组(n=20)。常规治疗组患者在肺保护性通气基础上行常规机械通气,肺复张组患者采用呼气末正压通气(positive end expiratory pressure,PEEP)递增法进行肺复张。比较两组患者治疗前后的动脉血气分析、呼吸力学指标、血流动力学指标和血清白细胞介素(interleukin,IL)-6及IL-10水平。结果 治疗后12h、24h,两组患者的动脉血氧分压(arterial partial pressure of oxygen,PaO_(2))、氧合指数(oxygenation index,OI)、肺静态顺应性(C_(stat))及肺动态顺应性(C_(dyn))均显著高于本组治疗前,肺泡动脉氧分压差[PO_(2)(A-a)]、呼吸指数(respiratory index,RI)、气道峰压(P_(peak))及气道平台压(P_(plat))均显著低于本组治疗前(P<0.05);肺复张组患者的PaO_(2)、OI、C_(stat)及C_(dyn)均显著高于常规治疗组,PO_(2)(A-a)、RI、P_(peak)及P_(plat)均显著低于常规治疗组(P<0.05)。肺复张组患者肺复张过程中收缩压及平均动脉压有所下降(P<0.05),中心静脉压有所升高(P<0.05),肺复张结束后均恢复至基线水平。治疗后12h,两组患者的血清IL-6和IL-10水平均显著低于本组治疗前(P<0.05)。结论 PEEP递增法肺复张可改善ATAAD术后低氧血症患者的氧合及肺顺应性,但对血流动力学存在一过性影响,治疗时应进行严密监测。
文摘Background It is still controversial as to the implementation of higher positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS). This study was conducted to compare the lower and higher PEEP in patients with ARDS ventilated with low tidal volume, to investigate the relationship between the recruited lung volume by higher PEEP and relevant independent variables and to provide a bedside estimate of the percentage of potentially recruitable lung by higher PEEP. Methods Twenty-four patients with ARDS were studied. A lung recruiting maneuver was performed, then each patient was ventilated with PEEP of 8 cmH20 for 4 hours and subsequently with PEEP of 16 cmH20 for 4 hours. At the end of each PEEP level period, gas exchange, hemodynamic data, lung mechanics, stress index "b" of the dynamic pressure-time curve, intrinsic PEEP and recruited volume by PEEP were measured. Results Fourteen patients were recruiters whose alveolar recruited volumes induced by PEEP 16 cmH20 were (425_+65) ml and 10 patients were non-recruiters. Compared with the PEEP 8 cmH20 period, after the application of the PEEP 16 cmH20, the PaO2/FiO2 ratio and static lung compliance both remained unchanged in non-recruiters, whereas they increased significantly in recruiters. Changes in PaO2/FiO2 and static lung compliance after PEEP increase were independently associated with the alveolar recruitment. Analyzing the relationship between recruiting maneuver (RM)-induced change in end-expiratory lung volume and the alveolar recruitment induced by PEEP, we found a notable correlation. Conclusions The results of this study indicated that the potential for alveolar recruitment might vary among the ARDS population and the higher PEEP levels should be limited to recruiters. Improving in PaO2/FiO2, static lung compliance after PEEP increase and the shape of the pressure-time curve could be helpful for PEEP application.
文摘肺脏肿瘤是一种高发病率、高致死率疾病[1],在发展早期主要依赖NK细胞等淋巴细胞发挥抗肿瘤作用[2],其中CXCR3^(+)NK细胞可依赖CXCL9/10等趋化因子的招募作用[3]而快速迁移,并大量分泌IFN-γ和穿孔素等效应因子,发挥免疫监视等作用[4]。桔梗-姜半夏配伍(the combination of Platycodon Grandiflorum and Pinella Ternata,PG+PT)常用于肿瘤的临床治疗中[5]。本研究旨在探讨PG+PT对肺脏肿瘤微环境中NK细胞、特别是CXCR3+NK的免疫药理作用,以明确该配伍发挥抗肿瘤作用的部分药理机制。
文摘Background:Coronavirus disease 2019(COVID-19)has been frequently complicated by severe acute respiratory distress syndrome(ARDS)with prolonged invasive ventilation.While respiratory system compliance and lung recruitability have been described within the first days after ICU admission,data about their longitudinal changes are still limited.Therefore,we conducted this study to assess the evolution of respiratory system compliance and lung recruitability in patients with COVID-19–related ARDS.Method:We conducted a prospective single-center study in patients admitted for COVID-19–related ARDS during the first wave of the pandemic,from March 16,2020 to April 10,2020.Respiratory system compliance was calculated daily at clinical positive end-expiratory pressure(PEEP)during passive breathing.The potential for lung recruitment was assessed by measuring the volume derecruited between PEEP 15 cmH2 O and 5 cmH2 O,and using the calculation of the recruitment-to-inflation ratio(R/I ratio).Recruitable lung was considered when the R/I ratio was at least 0.5.The primary outcome was the evolution of respiratory mechanics over time.The secondary outcome was the evolution of lung recruitability over time.Results:Thirty-two patients were included in this study.The respiratory mechanics were assessed 222 times(7±5 times per patient).Respiratory system compliance at clinical PEEP was 29.1 mL/cmH2 O(interquartile range[IQR]:24.1–33.9 mL/cmH2 O)and decreased significantly over time(P<0.0001).Lung recruitability was assessed in 22 out of the 32 patients(60 assessments).The median volume derecruited between PEEP 15 cmH2 O and 5 cmH2 O was 246.8 mL(IQR:180.8–352.2 mL)and the median R/I ratio was 0.56(IQR:0.39–0.73).Neither changed significantly over time.The proportion of patients with recruitable lung was 50.0%(6/12)within the first 3 days after intubation,69.2%(9/13)between day 4 and day 7,and 66.7%(8/12)after day 7(P=0.7934).Conclusions:In our cohort,respiratory system compliance was low and decreased over time.The potential for lung recruitment was high and persisted despite prolonged mechanical ventilation,suggesting that maintaining high PEEP levels in the later course of COVID-19 could be adequate.