To establish a stable and reliable model of refractory hypoxemia acute respiratory distress syndrome (ARDS) and examine its pathological mechanisms, a total of 144 healthy male Wistar rats were randomized into 4 gro...To establish a stable and reliable model of refractory hypoxemia acute respiratory distress syndrome (ARDS) and examine its pathological mechanisms, a total of 144 healthy male Wistar rats were randomized into 4 groups: group Ⅰ (saline control group), group Ⅱ (LPS intravenous "single-hit" group), group Ⅲ (LPS intratracheal "single-hit" group) and Group IV (LPS "two-hit" group). Rats were intravenously injected or intratracheally instilled with a large dose of LPS (10 mg/kg in 0.5 mL) to simulate a single attack of ARDS, or intraperitoneally injected with a small dose of LPS (1 mg/kg) followed by tracheal instillation with median dose of LPS (5 mg/kg) to establish a "two-hit" model. Rats in each group were monitored by arterial blood gas analysis and visual inspection for three consecutive days. Arterial blood gas values, lung wet/dry weight ratio and pathological pulmonary changes were analyzed to determine the effects of each ALI/ARDS model. Concentrations of TNF-α, IL-1 and IL-10 in the bronchoalveolar lavage fluid (BALF) and blood plasma were meastired by using enzyme-linked immunosorbent assays (ELISA). Our resulsts showed that single LPS-stimulation, whether through intravenous injection or tracheal instillation, could only induce ALl and temporary hypoxemia in rats. A two-hit LPS stimulation induces prolonged hypoxemia and specific pulmonary injury in rats, and is therefore a more ideal approximation of ARDS in the animal model. The pathogenesis of LPS two-hit-induced ARDS is associated with an uncontrolled systemic inflammatory response and inflammatory injury. It is concluded that the rat ARDS model produced by our LPS two-hit method is more stable and reliable than previous models, and closer to the diagnostic criteria of ARDS, and better mimics the pathological process of ARDS.展开更多
BACKGROUND: Pulmonary stretch reflex plays an important role in regulation of respiratorymovement. This study aimed to evaluate the effect of pulmonary stretch reflex on lung injury inrabbits with acute respiratory d...BACKGROUND: Pulmonary stretch reflex plays an important role in regulation of respiratorymovement. This study aimed to evaluate the effect of pulmonary stretch reflex on lung injury inrabbits with acute respiratory distress syndrome (ARDS).METHODS: ARDS rabbits were given intratracheal infusion of hydrochloric acid and ventilatedwith neurally adjusted ventilatory assistance (NAVA) with a tidal volume (VT) of 6 mL/kg and theelectrical activity of diaphragm (EAdi)-determined positive end expiratory pressure. After isolation ofthe bilateral vagus nerve trunk, the rabbits were randomized into two groups: sham operation (SHAM)group (n=5) and bilateral vagotomy (VAG) group (n=5). Gas exchange and respiratory mechanicswere detected at baseline, after lung injury and 1, 2, and 3 hours after ventilation respectively.Pulmonary permeability index, pathological changes and infl ammatory response were also measured.RESULTS: Compared with the SHAM group, PaO2/FiO2 in the VAG group decreased signifi cantly2 and 3 hours after ventilation (P〈0.05). There was no significant difference in PaCO2 betweenthe SHAM and VAG groups (P〉0.05), and the VAG group had a high VT, peak pressure (Ppeak),and mean pressure (Pm) compared with the SHAM group 1, 2, 3 hours after ventilation (P〈0.05).Compared to the SHAM group, dead space fraction (VD/VT) and respiratory system elastance (Ers)in the VAG group increased (P〈0.05) and static pulmonary compliance (Cst) decreased markedly(P〈0.05) after ventilation for 3 hours. Lung wet/dry weight ratio (W/D) (8.4±1.2 vs. 6.6±1.0), lung injuryscore (6.3±1.8 vs. 3.8±1.3), tumor necrosis factor-# (TNF-#) (779±372 pg/mL vs. 355±130 pg/mL)and interleukin-8 (IL-8) (169±21 pg/mL vs. 118±17 pg/mL) increased significantly in the VAG groupcompared with the SHAM group (P〈0.05).CONCLUSION: Lung injury is aggravated after bilateral vagotomy, demonstrating thatpulmonary stretch refl ex may have protective effect on the lung.展开更多
A 58-year-old Asian female developed acute respiratory distress syndrome (ARDS) following anaphylactic shock. Several similar cases have been reported in the literature, attributed to the pathophysiological mechanisms...A 58-year-old Asian female developed acute respiratory distress syndrome (ARDS) following anaphylactic shock. Several similar cases have been reported in the literature, attributed to the pathophysiological mechanisms of anaphylaxis or interestingly, the treatment itself;adrenaline, majority of the latter being related to administration of supra-therapeutic doses. According to our clinical experience, the possibility of ARDS should be considered in <span>patients who develop unexplainable hypoxaemia following anaphylactic</span><span> shock. </span><span>This case report discusses the pathophysiology of ARDS both in anaphylaxis and following epinephrine treatment and key aspects of management of ARDS with </span><span>a </span><span>main focus on the role of high flow oxygen, diuretics and anxiolytics. </span><span>T</span><span>he </span><span>importance of avoiding drug administration errors is also highlighted.</span>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
基金supported by a grant from the Shanghai Education Committee(No.2005-81)
文摘To establish a stable and reliable model of refractory hypoxemia acute respiratory distress syndrome (ARDS) and examine its pathological mechanisms, a total of 144 healthy male Wistar rats were randomized into 4 groups: group Ⅰ (saline control group), group Ⅱ (LPS intravenous "single-hit" group), group Ⅲ (LPS intratracheal "single-hit" group) and Group IV (LPS "two-hit" group). Rats were intravenously injected or intratracheally instilled with a large dose of LPS (10 mg/kg in 0.5 mL) to simulate a single attack of ARDS, or intraperitoneally injected with a small dose of LPS (1 mg/kg) followed by tracheal instillation with median dose of LPS (5 mg/kg) to establish a "two-hit" model. Rats in each group were monitored by arterial blood gas analysis and visual inspection for three consecutive days. Arterial blood gas values, lung wet/dry weight ratio and pathological pulmonary changes were analyzed to determine the effects of each ALI/ARDS model. Concentrations of TNF-α, IL-1 and IL-10 in the bronchoalveolar lavage fluid (BALF) and blood plasma were meastired by using enzyme-linked immunosorbent assays (ELISA). Our resulsts showed that single LPS-stimulation, whether through intravenous injection or tracheal instillation, could only induce ALl and temporary hypoxemia in rats. A two-hit LPS stimulation induces prolonged hypoxemia and specific pulmonary injury in rats, and is therefore a more ideal approximation of ARDS in the animal model. The pathogenesis of LPS two-hit-induced ARDS is associated with an uncontrolled systemic inflammatory response and inflammatory injury. It is concluded that the rat ARDS model produced by our LPS two-hit method is more stable and reliable than previous models, and closer to the diagnostic criteria of ARDS, and better mimics the pathological process of ARDS.
文摘BACKGROUND: Pulmonary stretch reflex plays an important role in regulation of respiratorymovement. This study aimed to evaluate the effect of pulmonary stretch reflex on lung injury inrabbits with acute respiratory distress syndrome (ARDS).METHODS: ARDS rabbits were given intratracheal infusion of hydrochloric acid and ventilatedwith neurally adjusted ventilatory assistance (NAVA) with a tidal volume (VT) of 6 mL/kg and theelectrical activity of diaphragm (EAdi)-determined positive end expiratory pressure. After isolation ofthe bilateral vagus nerve trunk, the rabbits were randomized into two groups: sham operation (SHAM)group (n=5) and bilateral vagotomy (VAG) group (n=5). Gas exchange and respiratory mechanicswere detected at baseline, after lung injury and 1, 2, and 3 hours after ventilation respectively.Pulmonary permeability index, pathological changes and infl ammatory response were also measured.RESULTS: Compared with the SHAM group, PaO2/FiO2 in the VAG group decreased signifi cantly2 and 3 hours after ventilation (P〈0.05). There was no significant difference in PaCO2 betweenthe SHAM and VAG groups (P〉0.05), and the VAG group had a high VT, peak pressure (Ppeak),and mean pressure (Pm) compared with the SHAM group 1, 2, 3 hours after ventilation (P〈0.05).Compared to the SHAM group, dead space fraction (VD/VT) and respiratory system elastance (Ers)in the VAG group increased (P〈0.05) and static pulmonary compliance (Cst) decreased markedly(P〈0.05) after ventilation for 3 hours. Lung wet/dry weight ratio (W/D) (8.4±1.2 vs. 6.6±1.0), lung injuryscore (6.3±1.8 vs. 3.8±1.3), tumor necrosis factor-# (TNF-#) (779±372 pg/mL vs. 355±130 pg/mL)and interleukin-8 (IL-8) (169±21 pg/mL vs. 118±17 pg/mL) increased significantly in the VAG groupcompared with the SHAM group (P〈0.05).CONCLUSION: Lung injury is aggravated after bilateral vagotomy, demonstrating thatpulmonary stretch refl ex may have protective effect on the lung.
文摘A 58-year-old Asian female developed acute respiratory distress syndrome (ARDS) following anaphylactic shock. Several similar cases have been reported in the literature, attributed to the pathophysiological mechanisms of anaphylaxis or interestingly, the treatment itself;adrenaline, majority of the latter being related to administration of supra-therapeutic doses. According to our clinical experience, the possibility of ARDS should be considered in <span>patients who develop unexplainable hypoxaemia following anaphylactic</span><span> shock. </span><span>This case report discusses the pathophysiology of ARDS both in anaphylaxis and following epinephrine treatment and key aspects of management of ARDS with </span><span>a </span><span>main focus on the role of high flow oxygen, diuretics and anxiolytics. </span><span>T</span><span>he </span><span>importance of avoiding drug administration errors is also highlighted.</span>
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.