Lung injury could be classified as acute and chronic injuries, such as acute respiratory distress syndrome and chronic obstructive pulmonary disease. Lung function recovery mainly depends on inflammation adjusting, lung and airway remodeling, endogenous stem cell proliferation and differentiation, and tissue repair. The principles of clinical therapy include inhibition of inflammation, balancing coagulation and fibrinolysis, and protective lung ventilation for acute lung injury; while reduction of hyper-secretion, bronchodilation, adjusting airway mucosal inflammation and immunity, as well as improving airway remodeling for chronic obstructive pulmonary disease. The functional recovery of lung and airway depends on endogenous stem cell proliferation and repair. The purpose of clinical treatment is to provide assistance for lung and airway repair besides pathophysiological improvement.
Acute lung injury is one of the common and serious complications of acute aortic dissection, and it greatly affects the recovery of patients. Old age, overweight, hypoxemia, smoking history, hypotension, extensive involvement of dissection and pleural effusion are possible risk factors for the acute lung injury before operation. In addition, deep hypothermia circulatory arrest and blood product infusion can further aggravate the acute lung injury during operation. In this paper, researches on risk factors, prediction model, prevention and treatment of acute aortic dissection with acute lung injury were reviewed, in order to provide assistance for clinical diagnosis and treatment.
Objective To investigate the efficacy of early, short-term, low-dose corticosteroid administration for the prevention and treatment of early acute lung injury (EALI) in patients undergoing thoracoscopic lobectomy. MethodsA retrospective analysis was conducted on the clinical data of patients who underwent thoracoscopic lobectomy at the Department of Thoracic and Cardiovascular Surgery, Taihe Hospital, Hubei University of Medicine, from January 2019 to January 2022. Patients were divided into an early steroid therapy group and an observation group based on whether they received corticosteroids in the early postoperative period. In the early steroid therapy group, in addition to standard postoperative care, patients received a low-dose intravenous push of methylprednisolone (80-120 mg/d) for 3 consecutive days. In the observation group, patients received standard postoperative care without intravenous corticosteroids for the first 3 days. Chest plain CT scans were performed on postoperative day (POD) 1 and POD 3 or 4 to evaluate lung injury. CT scores and the incidence of postoperative EALI were recorded. ResultsA total of 521 patients were included (268 males, 253 females; age range: 11-80 years). There were 318 patients in the observation group and 203 in the early steroid therapy group. On POD 1, the incidence of EALI was 16.0% in the observation group and 13.8% in the early steroid therapy group, with no statistical difference (P=0.486). Correspondingly, there was no statistical difference in chest CT scores among EALI-positive patients between the two groups (P=0.927). On POD 3-4, the incidence of EALI was significantly lower in the early steroid therapy group (22.7%) compared to the observation group (33.6%) (P=0.007). Although chest CT scores among EALI-positive patients were lower in the early steroid therapy group, the difference was not statistically significant (P=0.377). The overall incidence of EALI within the first 4 postoperative days was significantly lower in the early steroid therapy group (26.1%) than in the observation group (37.4%) (P=0.007). Radiological progression (defined as new-onset EALI or progression of existing EALI) occurred in 14.8% of the early steroid therapy group, significantly lower than the 28.9% in the observation group (P<0.001). The early steroid therapy group had a shorter postoperative length of stay (P<0.001), while there was no statistical difference in the incidence of poor wound healing between the groups (P=0.762). Conclusion Early postoperative corticosteroid use effectively reduces the incidence of EALI on POD 3-4, lowers the risk of radiological progression, and decreases the overall incidence of postoperative EALI. This is achieved without prolonging the length of stay or increasing the risk of poor wound healing. Therefore, early administration of low-dose corticosteroids is beneficial in suppressing the occurrence and progression of EALI. Its early use is recommended for patients at high risk for postoperative EALI.
Objective To investigate the changes in osteoprotegerin (OPG) / receptor activator of nuclear factor-κB ligand (RANKL) ratio in sepsis-associated acute lung injury (SA-ALI) and the role of regulation of this ratio on the inflammatory response in SA-ALI. Methods Eighteen C57BL/6 male mice were randomly divided into sham operation group, cecal ligation and perforation (CLP) group and RANKL group, with 6 mice in each group. Before the experiment, the RANKL group was intraperitoneally injected with 5 μg (0.2 mL) of recombinant RANKL antibody, whereas both the sham operation group and the CLP group were intraperitoneally injected with a volume-matched normal saline. One hour later, the sham operation group underwent only abdominal exploration and repositioning, while the other groups underwent the CLP surgery to induce the SA-ALI model. After 24 h of modelling, all mice were sacrificed and samples were collected. Pathological evaluation of lung tissues was performed by haematoxylin-eosin staining; enzyme-linked immunosorbent assay was used to detect serum concentrations of interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1β; while the mRNA and protein expression of OPG and RANKL, along with their ratio values, were detected by real-time polymerase chain reaction for quantitative analysis and protein immunoblotting. Results The SA-ALI mouse model was successfully established. Compared with the sham operation group, mice in the CLP group showed disturbed alveolar structure, obvious alveolar and interstitial haemorrhage and inflammatory cell infiltration, elevated serum levels of IL-6, TNF-α and IL-1β (P<0.05), significantly increased mRNA and protein expression of OPG and elevated OPG/RANKL ratio in lung tissue (P<0.05), whereas RANKL mRNA and protein expression was significantly decreased (P<0.05). Compared with the CLP group, the pathological damage of lung tissue in the RANKL group was reduced, the infiltration of alveolar and interstitial inflammatory cells was significantly improved, and the alveolar structure and morphology were more regular, with lower serum levels of IL-6, TNF-α and IL-1β (P<0.05), significantly lower mRNA and protein expression of OPG and OPG/RANKL ratio in lung tissue (P<0.05), and significantly higher mRNA and protein expression of RANKL in lung tissue (P<0.05). Conclusion The alteration of OPG/RANKL ratio may be related to the pathophysiological process of SA-ALI, and the decrease in its level may reflect the attenuation of the inflammatory response in SA-ALI.
ObjectiveTo study the expression of cytokine-induced neutrophil chemoattractant-1(CINC-1)in rats with transfusion-related acute lung injury(TRALI),explore its possible role in the pathogenesis of TRALI. MethodsSixty Sprague-Dawley rats were randomly divided into a normal control group with sham operation,a positive control group with ALI induced by intravenous infusion of lipopolysaccharide(5 mg/kg),and a TRALI group treated by intraperitoneal injection of LPS 2h before the transfusion of human plasma (1mL),a LPS control group treated by intraperitoneal injection of LPS 2h before the transfusion of normal saline(1mL).The reverse transcription-polymerase chain (RT-PCR)was used to detect CINC-1 mRNA.The level of CINC-1 in lung tissue homogenate was measured by ELISA.Morphological changes of the lung tissue were observed under light microscope.Myeloperoxidase (MPO)in lung homogenate and wet lung weight to dry lung weight ratio (W/D)were observed.The number of cells and the percentage of polymorphonuclear neutrophil (PMN)in Bronchoalveolar lavage fluid (BALF)were also compared. ResultsCompared with the normal control group and the LPS control group,the expression of CINC-1 protein and CINC-1 mRNA were increased significantly in lung of the positive control group and the TRALI group(P<0.05).The number of cells and the percentage of PMN in BALF of the TRALI group [(310.63±76.67)×106/L and (33.57±11.51)%] were significantly higher than those in BALF of the normal control group [(101.36±63.83)×106/L and (9.87±3.56)%](P<0.05).Tissue water content and MPO activity in the TRALI group were significantly higher than those in the normal control group (P<0.05). ConclusionExpression of CINC-1 protein and CINC-1 mRNA are increased in the rat lung with TRALI and PMN infiltration in lung tissue,which suggests CINC-1 participate in the process of the PMN and endothelial cell adhesion and may play an important role in the pathogeneses of TRALI.
Objective To investigate the effects of wedelolactone (WEL) on lipopolysaccharide (LPS)-induced pyroptosis of alveolar epithelial cells and AMP-activated protein kinase/nucleotide binding oligomeric domain like receptor 3 (NLRP3)/cysteinyl aspartate specific proteinase-1 (Caspase-1) signaling pathway. Methods Human lung epithelial cells BEAS-2B were treated with 5 - 200 μmol/L wedelolactone, and cell activity was detected using MTT assay. The alveolar epithelial cells were divided into control group, lipopolysaccharide group (LPS group), 10 μmol/L wedelolactone group (WEL-L group), 20 μmol/L wedelolactone group (WEL-M group), 40 μmol/L wedelolactone group (WEL-H group), 40 μmol/L wedelolactone+10 μmol/L AMPK inhibitor Compound C group (WEL-H+Compound C group), and 20 μmol/L Caspase-1 inhibitor Z-YVAD-FMK group (Z-YVAD-FMK group). Transmission electron microscopy was applied to observe the microstructure of cells. ELISA was applied to detect levels of inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-8 (IL-8). Immunofluorescence was applied to detect Caspase-1 and gasdermin family proteins (DGSDMD). Western blot was applied to detect protein expression levels of AMPK, NLRP3, and Caspase-1. Results Wedelolactone concentrations of 10, 20 and 40 μmol/L were selected for follow-up experiments. Compared with Control group, LPS group showed decreased cell activity, severe damage, cell contraction, mitochondrial ridge breakage and decreased number, increased levels of TNF-α, IL-1β, IL-8 and GSDMD, NLRP3, Caspase-1 expression, and decreased p-AMPK/AMPK expression (P<0.05). Wedelolactone treatment could significantly improve LPS-induced pyrosis of alveolar epithelial cells (P<0.05). Compound C could partially reverse the effect of wedelactone on LPS-induced pyrodeath of alveolar epithelial cells (P<0.05). Z-YVAD-FMK treatment also significantly improved LPS-induced pyroptosis of alveolar epithelial cells (P<0.05). Conclusion Wedelolactone can inhibit LPS-induced pyroptosis of pulmonary alveolar epithelial cells by inhibiting AMPK/NLRP3/Caspase-1 signaling pathway.
Acute lung injury is a kind of common complication after cardiopulmonary bypass. Acute lung injury is attributed to the ischemia-reperfusion injury and systemic inflammatory response syndrome. Several factors common in cardiac surgery with cardiopulmonary bypass may worsen the risk for acute lung injury including atelectasis, transfusion requirement, older age, heart failure, emergency surgery and prolonged duration of bypass. Targets for prevention of acute lung injury include mechanical, surgical and anesthetic interventions that aim to reduce the contact activation, systemic inflammatory response, leukocyte sequestration and hemodilution associated with cardiopulmonary bypass. We aim to review the etiology, risk factors and lung protective strategies for acute lung injury after cardiopulmonary bypass.
ObjectiveTo investigate the effects of human placental mesenchymal stem cells (hPMSCs) transplantation on pulmonary vascular endothelial permeability and lung injury repair in mice with lipopolysaccharide (LPS)-induced acute lung injury (ALI).MethodsThe hPMSCs were isolated from the human placental tissue by enzyme digestion and passaged. The cell phenotype of the 3rd generation hPMSCs was detected by flow cytometry. Twenty-four 6-week-old healthy male C57BL/6 mice were randomly divided into 3 groups (n=8). The mice were instilled with LPS in the airway to prepare an ALI model in the ALI model group and the hPMSCs treatment group, and with saline in the control group. At 12 hours after LPS infusion, the mice were injected with 3rd generation hPMSCs via the tail vein in hPMSCs treatment group and with saline in the ALI model group and the control group. At 24 hours after injection, the lung tissues of all mice were taken. The pathological changes were observed by HE staining. The wet/dry mass ratio (W/D) of lung tissue was measured. The Evans blue leak test was used to detect the pulmonary vascular endothelial permea bility in mice. The expression of lung tissue permeability-related protein (VE-cadherin) was detected by Western blot.ResultsFlow cytometry examination showed that the isolated cells had typical MSCs phenotypic characteristics. Mice in each group survived. The alveolar structure of the ALI model group significantly collapsed, a large number of inflammatory cells infiltrated, and local alveolar hemorrhage occurred; while the alveolar structure collapse of the hPMSCs treatment group significantly improved, inflammatory cells infiltration significantly reduced, and a few red blood cells were in the interstitial lung. W/D and exudation volume of Evans blue stain were significantly higher in the ALI model group than in the control group and the hPMSCs treatment group (P<0.05), in the hPMSCs treatment group than in the control group (P<0.05). The relative protein expression of VE-cadherin was significantly lower in the ALI model group than in the control group and the hPMSCs treatment group (P<0.05), and in the hPMSCs treatment group than in the control group (P<0.05).ConclusionIntravenous injection of hPMSCs can effectively reduce the increased pulmonary vascular endothelial permeability mediated by LPS, relieve the degree of lung tissue damage, and play a therapeutic role in ALI mice.
ObjectiveTo investigate the value of chest high-resolution computed tomography (HRCT) score in evaluating the severity of hip fracture-induced early acute lung injury (ALI) in the elderly patients.MethodsThe clinical data of 289 elderly hip fracture patients in Chongqing Traditional Chinese Medicine Hospital from July 2014 to April 2020 were retrospectively analyzed. All patients were divided into two groups, including an ALI group (n=114, 36 males and 78 females at age of 82.94±6.85 years) and a non-ALI group (n=175, 51 males and 124 females at age of 84.42±6.31 years). General information, chest HRCT scores and PaO2/FiO2 were compared between the two groups. Correlation analysis was used to compare the relationship between chest HRCT scores and PaO2/FiO2. Multiple linear stepwise regression analysis was applied to evaluate the effective extent of the diffuse ground glass opacity (DGGO), intense parenchymal opacification (IPO), and reticulation HRCT scores to the overall HRCT scores.ResultsThe DGGO scores, IPO scores, reticulation scores, overall HRCT scores and PaO2/FiO2 were higher in the ALI group than those in the non-ALI group (P<0.001). In the ALI group, correlation analysis showed that DGGO, overall HRCT scores were in significantly negative correlation with PaO2/FiO2 (P<0.001). In addition, the correlation among PaO2/FiO2 and overall HRCT scores was more significant than that of DGGO scores. Multiple stepwise regression analysis indicated that DGGO, IPO, and reticulation scores were independent influencing factors for overall HRCT scores. Among the influencing factors, DGGO scores had the greatest impact, then IPO scores and reticulation scores. The HRCT signs of DGGO, IPO, and reticulation appeared simultaneously had the greatest effects on the overall HRCT scores.ConclusionThe chest HRCT score, which is associated with PaO2/FiO2, also can be used in the severity assessment of elderly patients with early ALI caused by hip fracture.
Sepsis-associated organ dysfunction arises from uncontrolled inflammation and immune dysregulation, causing microcirculatory impairment and multi-organ failure. Stellate ganglion block (SGB) may confer organ protection by regulating the sympathetic nervous system and hypothalamic-pituitary-adrenal axis to suppress excessive inflammation and oxidative stress. Available evidence, mainly from experimental and small clinical studies, suggests potential benefits of SGB in sepsis-induced acute lung injury, ventricular arrhythmias, and limb ischemia, which require confirmation in multicenter randomized controlled trials. This review outlines the mechanisms and clinical advances of SGB in sepsis-related organ dysfunction, providing a theoretical basis for its application in critical care.