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
Acute respiratory distress syndrome(ARDS) is a syndrome with heterogeneous underlying pathological processes. It represents a common clinical problem in intensive care unit patients and it is characterized by high mor...Acute respiratory distress syndrome(ARDS) is a syndrome with heterogeneous underlying pathological processes. It represents a common clinical problem in intensive care unit patients and it is characterized by high mortality. The mainstay of treatment for ARDS is lung protective ventilation with low tidal volumes and positive end-expiratory pressure sufficient for alveolar recruitment. Prone positioning is a supplementary strategy available in managing patients with ARDS. It was first described 40 years ago and it proves to be in alignment with two major ARDS pathophysiological lung models; the "sponge lung"- and the "shape matching"-model. Current evidence strongly supports that prone positioning has beneficial effects on gas exchange, respiratory mechanics, lung protection and hemodynamics as it redistributes transpulmonary pressure, stress and strain throughout the lung and unloads the right ventricle. The factors that individually influence the time course of alveolar recruitment and the improvement in oxygenation during prone positioning have not been well characterized. Although patients' response to prone positioning is quite variable and hard to predict, large randomized trials and recent meta-analyses show that prone position in conjunction with a lung-protective strategy, when performed early and in sufficient duration, may improve survival in patients with ARDS. This pathophysiology-based review and recent clinical evidence strongly support the use of prone positioning in the early management of severe ARDS systematically and not as a rescue maneuver or a last-ditch effort.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
BACKGROUND: Data on the mechanical ventilation(MV) characteristics and radiologic features for the cases with H7 N9-induced ARDS were still lacking.METHODS: We describe the MV characteristics and radiologic features o...BACKGROUND: Data on the mechanical ventilation(MV) characteristics and radiologic features for the cases with H7 N9-induced ARDS were still lacking.METHODS: We describe the MV characteristics and radiologic features of adult patients with ARDS due to microbiologically confirmed H7 N9 admitted to our ICU over a 3-month period.RESULTS: Eight patients(mean age 57.38±16.75; 5 male) were diagnosed with H7 N9 in the first quarter of 2014. All developed respiratory failure complicated by acute respiratory distress syndrome(ARDS), which required MV in ICU. The baseline APACHE II and SOFA score was 11.77±6.32 and 7.71±3.12. The overall CT scores of the patients was 247.68±34.28 and the range of CT scores was 196.3–294.7. The average MV days was 14.63±6.14, and 4 patients required additional rescue therapies for refractory hypoxemia. Despite these measures, 3 patients died.CONCLUSION: In H7 N9-infected patients with ARDS, low tidal volume strategy was the conventional mode. RM as one of rescue therapies to refractory hypoxemia in these patients with serious architectural distortion and high CT scores, which could cause further lung damage, may induce bad outcomes and requires serious consideration. Prone ventilation may improve mortality, and should be performed at the early stage of the disease, not as a rescue therapy.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
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Acute respiratory distress syndrome(ARDS) is a syndrome with heterogeneous underlying pathological processes. It represents a common clinical problem in intensive care unit patients and it is characterized by high mortality. The mainstay of treatment for ARDS is lung protective ventilation with low tidal volumes and positive end-expiratory pressure sufficient for alveolar recruitment. Prone positioning is a supplementary strategy available in managing patients with ARDS. It was first described 40 years ago and it proves to be in alignment with two major ARDS pathophysiological lung models; the "sponge lung"- and the "shape matching"-model. Current evidence strongly supports that prone positioning has beneficial effects on gas exchange, respiratory mechanics, lung protection and hemodynamics as it redistributes transpulmonary pressure, stress and strain throughout the lung and unloads the right ventricle. The factors that individually influence the time course of alveolar recruitment and the improvement in oxygenation during prone positioning have not been well characterized. Although patients' response to prone positioning is quite variable and hard to predict, large randomized trials and recent meta-analyses show that prone position in conjunction with a lung-protective strategy, when performed early and in sufficient duration, may improve survival in patients with ARDS. This pathophysiology-based review and recent clinical evidence strongly support the use of prone positioning in the early management of severe ARDS systematically and not as a rescue maneuver or a last-ditch effort.
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.
基金supported by the National Natural Science Foundation of China(grant number 81501654)Natural Science Foundation of Shanghai(grant number 14ZR1433700)
文摘BACKGROUND: Data on the mechanical ventilation(MV) characteristics and radiologic features for the cases with H7 N9-induced ARDS were still lacking.METHODS: We describe the MV characteristics and radiologic features of adult patients with ARDS due to microbiologically confirmed H7 N9 admitted to our ICU over a 3-month period.RESULTS: Eight patients(mean age 57.38±16.75; 5 male) were diagnosed with H7 N9 in the first quarter of 2014. All developed respiratory failure complicated by acute respiratory distress syndrome(ARDS), which required MV in ICU. The baseline APACHE II and SOFA score was 11.77±6.32 and 7.71±3.12. The overall CT scores of the patients was 247.68±34.28 and the range of CT scores was 196.3–294.7. The average MV days was 14.63±6.14, and 4 patients required additional rescue therapies for refractory hypoxemia. Despite these measures, 3 patients died.CONCLUSION: In H7 N9-infected patients with ARDS, low tidal volume strategy was the conventional mode. RM as one of rescue therapies to refractory hypoxemia in these patients with serious architectural distortion and high CT scores, which could cause further lung damage, may induce bad outcomes and requires serious consideration. Prone ventilation may improve mortality, and should be performed at the early stage of the disease, not as a rescue therapy.
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.
