Extravascular lung water volume measurement by a novel lithium-thermal indicator dilution method: comparison of three techniques to post-mortem gravimetry

Objective  To compare the lithium-thermal double indicator dilution (Li-thermal), indocyanine green-thermal double indicator dilution (ICG-thermal), single thermal indicator dilution (single-thermal) and gravimetric techniques of extravascular lung water volume (EVLW) measurement in porcine models of acute lung injury. Design  Two animal models designed to invoke a systemic inflammatory response. Setting  Laboratory study. Subjects  A total of 12 immature Deutsches Landschwein pigs. Interventions  Extravascular lung water volume was measured at four time points using Li-thermal, ICG-thermal and single-thermal techniques. Measurements were performed using existing technology according to manufacturer’s instructions. Post-mortem gravimetric EVLW measurements were performed by measuring wet and dry mass of lung tissue. Measurements were compared using the Bland–Altman method. Data are presented as mean (SD). Measurements and main results  Data were collected in 12 animals and comparison between all 4 techniques was possible in 10 animals. EVLW measured by gravimetry was 9.2 (±3.0)ml kg⁻¹. When compared to gravimetry, both Li-thermal and ICG-thermal techniques showed minimal bias but wide limits of agreement (LOA) [Li-thermal: bias −1.8 ml kg⁻¹ (LOA ± 13.1); ICG-thermal bias −1.0 ml kg⁻¹ (LOA ± 6.6)]. Comparison between the single-thermal and gravimetric methods identified both considerable bias and wide LOA [+8.5 ml kg⁻¹ (LOA ± 14.5)]. Conclusion  Clinically significant differences between EVLW measurements obtained with the gravimetric method and three in vivo indicator dilution techniques were identified. While none of the techniques could be considered ideal, the ICG-thermal method appeared more reliable than either the Li-thermal or single thermal techniques. Further research is required to determine whether the accuracy of the prototype Li-thermal technique can be improved. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

血管外肺水监测对脓毒症急性肾损伤的应用研究

目的探讨血管外肺水监测(PICCO)在脓毒症合并急性肾损伤肾脏替代治疗(RRT)中的应用价值。方法选取2012年3月-2014年12月我院收治的脓毒症合并急性肾损伤患者41例,在PICCO监测下,予每天6~8hRRT,根据血管外肺水指数(EVLWI)值分成观察组(EVLWI7mL/kg)21例和对照组(EVLWI≤7mL/kg)20例。观察初始液体复苏治疗后,两组患者氧合指数(PO_2/FiO_2)、动脉氧分压(PO_2)、经皮脉氧饱和度(SPO_2)、血乳酸值的变化。结果观察组液体复苏24h的PO_2/FiO_2明显低于治疗前及对照组(P0.05);观察组在液体复苏48h后PO_2/FiO_2开始恢复,但仍低于对照组(P0.05);两组患者液体复苏72h的PO_2/FiO_2恢复正常。观察组液体复苏24h的PO_2低于观察组(P0.05)。两组患者液体复苏24h的SPO_2均呈一过性下降,48h恢复正常,两组患者SPO_2液体复苏治疗前后及相互比较均无统计学差异(P0.05)。观察组与对照组液体复苏24h的血乳酸明显低于治疗前(P0.01),两组间比较差异无统计学意义(P0.05)。结论血管外肺水监测有助于脓毒症合并急性肾损伤患者氧合情况的观察与护理。     

血管外肺水与脓毒症相关性ALI/ARDS预后关系的Meta分析

目的 研究血管外肺水(EVLW)在预测脓毒症相关性急性肺损伤/急性呼吸窘迫综合征预后中的价值.方法 检索1991年到2011年国内外公开发表的关于血管外肺水与脓毒症相关性ALI/ARDS预后关系的中英文文献,通过Stata软件进行Meta分析.结果 根据纳入和剔除标准筛选出7篇文献,Meta分析表明脓毒症相关性急性肺损伤/急性呼吸窘迫综合征患者中死亡组3d内的EVLW均维持在较高水平,而存活组有明显下降趋势,两组EVLW差距日趋扩大(SMDd1＜SMDd2＜SMD.d3),首日:SMD d1=0.29,95％CI:0.047～0.532;次日:SMDd2=1.64,95％ CI:0.14-3.13;第3天:SMDd3 =1.83,95％ CI:0.56～3.10.结论 脓毒症相关性急性肺损伤/急性呼吸窘迫综合征发病早期EVLW水平及其动态变化可作为预后评估指标,持续高水平的EVLW将增加死亡风险.     

量化肺部物理治疗在重症急性胰腺炎合并急性肺损伤患者中的应用

目的探讨量化肺部物理治疗方法对重症急性胰腺炎合并急性肺损伤患者的疗效。方法选择ICU诊断为重症急性胰腺炎合并急性肺损伤患者112例,在肺部物理治疗的基础上,量化肺部物理治疗的步骤和方法,用三步缩唇呼吸法、四步有效咳嗽法、五步有效叩背法、六步雾化吸入法、吹气球、持续加温湿化氧疗等肺部物理护理方法,观察患者气管插管率、抽动脉血气计算氧合指数、入住ICU时间。结果经量化的肺部护理方法后重症急性胰腺炎合并急性肺损伤患者气管插管率为7．14％（8／112）,入住ICU时间为（10．00±7．85）d,积极有效的控制了急性肺损伤。结论量化肺部物理治疗是重症胰腺炎合并急性肺损伤肺部护理的有效护理方法之一。     

Biomarkers in acute lung injury: insights into the pathogenesis of acute lung injury

Studies of potential biomarkers of acute lung injury (ALI) have provided information relating to the pathophysiology of the mechanisms of lung injury and repair. The utility of biomarkers remains solely among research tools to investigate lung injury and repair mechanisms. Because of lack of sensitivity and specificity, they cannot be used in decision making in patients with ALI or acute respiratory distress syndrome. The authors reviewed known biomarkers in context of their major biologic activity. The continued interest in identifying and studying biomarkers is relevant, as it provides information regarding the mechanisms involved in lung injury and repair and how this may be helpful in identifying and designing future therapeutic targets and strategies and possibly identifying a sensitive and specific biomarker.     

Extravascular lung water to blood volume ratios as measures of pulmonary capillary permeability in nonseptic critically ill patients

Purpose

The aim of this study is to evaluate the value of extravascular lung water (EVLW) to intrathoracic blood volume, global end-diastolic volume, or pulmonary blood volume ratios as a reflection of pulmonary permeability in nonseptic critically ill patients with or at risk for acute lung injury/acute respiratory distress syndrome (ALI/ARDS).

Methods

Pulmonary permeability was measured by the pulmonary leak index (PLI) for ⁶⁷gallium-labeled transferrin and EVLW and blood volumes by the transpulmonary indicator dilution technique in 20 mechanically ventilated patients, before and after fluid loading, guided by changes in central venous pressure.

Results

Nine (45%) patients had ALI/ARDS according to current criteria. The PLI was high (≥30.0 × 10⁻³/min) in 25% before and 30% after fluid loading. The EVLW was high (≥10 mL/kg) in 10% before and in none after fluid loading and did not increase with fluid loading, whereas blood volumes increased. Before fluid loading, PLI related to EVLW/blood volume ratios (minimum r = 0.48, P = .032). After fluid loading, PLI related to EVLW to pulmonary blood volume or intrathoracic blood volume ratios (minimum r = 0.46, P = .041). The relations were unaffected by fluid loading and pressure forces.

Conclusions

The EVLW/blood volume ratios are determined, at least in part, by moderately increased pulmonary permeability in nonseptic critically ill patients with or at risk for ALI/ARDS, independent of fluid status and pressure forces. Normal ratios may help to exclude high permeability.     

The effect of high-frequency oscillatory ventilation combined with tracheal gas insufflation on extravascular lung water in patients with acute respiratory distress syndrome: A randomized,crossover, physiologic study

Purpose

High-frequency oscillation combined with tracheal gas insufflation (HFO-TGI) improves oxygenation in patients with acute respiratory distress syndrome (ARDS). There are limited physiologic data regarding the effects of HFO-TGI on hemodynamics and pulmonary edema during ARDS. The aim of this study was to investigate the effect of HFO-TGI on extravascular lung water (EVLW).

Materials and methods

We conducted a prospective, randomized, crossover study. Consecutive eligible patients with ARDS received sessions of conventional mechanical ventilation with recruitment maneuvers (RMs), followed by HFO-TGI with RMs, or vice versa. Each ventilatory technique was administered for 8 hours. The order of administration was randomly assigned. Arterial/central venous blood gas analysis and measurement of hemodynamic parameters and EVLW were performed at baseline and after each 8-hour period using the single-indicator thermodilution technique.

Results

Twelve patients received 32 sessions. Pao₂/fraction of inspired oxygen and respiratory system compliance were higher (P < .001 for both), whereas extravascular lung water index to predicted body weight and oxygenation index were lower (P = .021 and .029, respectively) in HFO-TGI compared with conventional mechanical ventilation. There was a significant correlation between Pao₂/fraction of inspired oxygen improvement and extravascular lung water index drop during HFO-TGI (Rs = − 0.452, P = .009).

Conclusions

High-frequency oscillation combined with tracheal gas insufflation improves gas exchange and lung mechanics in ARDS and potentially attenuates EVLW accumulation.     

大黄附子汤对重症急性胰腺炎肺损伤大鼠肺泡上皮屏障功能的影响

目的 探讨大黄附子汤对重症急性胰腺炎肺损伤大鼠肺上皮屏障功能的影响及意义.方法 96只SD大鼠随机分为假手术组、重症急性胰腺炎肺损伤组(SAP-ALI组)及大黄附子汤组三组,每组32只.各组再按3,6,12,24 h时间点分为四个亚组,每个亚组各8只.假手术组开腹后行空肠造瘘,翻动胰腺数次后关腹;SAP-ALI组在假手术组基础上经胰胆管逆行注入4%牛磺胆酸钠(1mL/kg),建立重症急性胰腺炎急性肺损伤模型;大黄附子汤组在SAP-ALI组基础上经空肠造瘘管注入大黄附子汤10 mL.各组按时间点分别于伤后3,6,12,24 h测定肺泡上皮通透性(AEP)、肺泡内液体清除率(ALCR)、总肺水量(TLW)和肺血管外肺水量(EVLW),同时测定血浆内毒素(ET)、血清淀粉酶含量,光镜下观察肺脏病理组织学变化.结果 与假手术组比较,SAP-ALI组大鼠术后3,6,12,24 h ALCR显著降低,TLW,EVLW及AEP呈明显升高趋势(P＜0.05或P＜0.01).与SAP-ALI组比较,大黄附子汤组对大鼠术后3,6,12,24 h ALCR均显著升高,TLW,EVLW及AEP呈明显降低趋势(P＜0.05或P＜0.01),且肺组织的水肿、出血、炎症程度及肺损伤学评分和肺湿/干重比均明显好转.结论 重症急性胰腺炎并急性肺损伤大鼠存在严重的肺泡上皮屏障功能障碍;大黄附子汤通过抑制内毒素过度释放,可降低炎症反应,改善肺泡上皮功能障碍,减轻肺损伤程度.

Abstract：

Objective To investigate effect of Dahuang Fuzi decoction on alveolaur epithelial barrier in rats with lung injury with severe acute pancreatitis. Method Ninty-six health SD rats were randomly divided into three groups: sham operation group, SAP-ALI group, Dahuang Fuzi decoction group, and then according to the time point of sacrifice after operation, each group was subdivided into 3,6,12,24 hour subsets ( each, n = 8). After the belly of a rat in the sham operation group was cut open, the pancreas was flipped several times,and then a stoma was made in the jejunum to form its fistula. In the SAP-ALl group,1 mL/kg sodium taurocholate was reversely injected into the pancreatobile duct to establish the model of SAP, and then the jejimum fistula was performed. The SAP-ALI model in Dahuang Fuzi decoction group was treated by injection of 10ml of Dahuang Fuzi decoctionon into the fistula respectively. Blood was collected from heart to detect serum amvlase and endotoxin (ET) levels before the rat being executed. The lung histopathologic changes, pulmonary injury scores and wet/dry weight(W/D) ratios were observed after the rats were executed. The alveolar liquid clearance rate(ALCR), total lung water content (TLW), extravascular lung water content(EVLW) and alveolar epithelial permeability (AEP) were examined in 3,6, 12,24 h after injury.Results There was continuous increase of AEP,TLW and EVLW,as well as progressive reduction of ALCR compared with sham operation group at 3,6,12,24 h after operation. Compared with SAP-ALI group, there was continuous decrease of AEP,TLW and EVLW, and elevated of ALCR at 3,6,12,24 h after operation.Conclusions Dahuang Fuzi decoction can significantly reduce alveolaur epithelial barrier and degree of lung tissue of SAP-ALI rats by inhibiting the elevation of LPS and inflammation reaction.     

经肺热稀释技术对急性肺损伤犬血管外肺水的监测

目的探讨经肺热稀释技术对不同原因急性肺损伤（ALI）血管外肺水（EVLW）测定的准确性。方法18只杂种犬随机分为正常组、外源性急性肺损伤组和内源性急性肺损伤组,每组6只,通过静脉注射油酸制备外源性ALI模型,气管内注入十六烷磺基丁二酸钠盐制备内源性ALI模型,然后分别向肺内灌注一定量的生理盐水,采用经肺热稀释法在灌注的前后测定EVLW,观察灌注前后EVLW变化与所灌注生理盐水量之间相关性。结果正常肺组织EVLW含量为（254．5±413．0）ml,肺泡灌注前后EVLW的变化与实际肺泡灌注生理盐水量之间具有良好的相关性（r=0．986,P〈0．01）;外源性ALI组EVLW含量为（483．3±11．5）ml,与正常组比较差异有统计学意义（P〈0．01）,ALI组肺泡灌注前后EVLW的变化与实际肺泡灌注生理盐水量之间也具有良好的相关性（r=0．978,P〈0．01）。内源性ALI组EVLW含量为（526．2±12．9）ml,与正常组比较差异有统计学意义（P〈0．01）。肺内源性ALI组肺泡灌注前后EVLW的变化与实际肺泡灌注生理盐水量之间具有较好的相关性（r=0．890,P〈0．01）,但不如外源性ALI组相关性高。结论经肺热稀释技术对EVLW的监测具有良好的准确性,但不同原因导致的EVLW增加的监测准确性不同。     

老年急性肾损伤与急性肺损伤相互作用及治疗策略

急性肾损伤(acute kidney injury,AKI)是系统性疾病,临床常合并急性肺损伤(acute lung injury,ALI),死亡率高,尤其见于老年患者.AKI与ALI通过多种因素介导相互作用、相互损伤,从而使死亡率急剧增高.本文主要关注老年AKI和Au相互作用的相关机制,探讨治疗策略,期待可以积累经验深化认识,改善患者预后.     

肺挫伤致急性呼吸窘迫综合征患者肺循环变化的临床研究

目的 用Swan-Ganz导管及脉搏指示连续心排血量(PiCCO)技术分析肺挫伤致急性呼吸窘迫综合征(ARDS)患者肺循环变化规律及意义.方法 采用前瞻性随机对照临床研究,选择2009年8月至2011年8月肺挫伤致ARDS患者(挫伤组,18例)和无肺挫伤且无ARdS的多发伤患者(对照组,22例),记录两组患者置管即刻及伤后12、24、36、48、60、72 h肺动脉收缩压(PAS)、肺动脉舒张压(PAD)、肺动脉楔压(PAWP)、肺动脉舒张压与肺动脉楔压梯度(PAD-PA WP)和血管外肺水指数(ELWI).比较各参数在组内和组间的差异.结果 肺挫伤致ARDS存活患者PAS、PAD和PAD-PAWP较对照组明显增高,之后逐渐回落,其中PAS、PAD于伤后60h,PAD-PAWP于伤后48 h恢复至对照组水平;而对照组PAS、PAD自置管即刻至伤后72 h无显著变化,PAD-PAWP伤后72 h较48 h增高.肺挫伤组ELWI较对照组明显升高,至12h达峰值后逐渐回落,于伤后60h恢复至对照组水平,对照组伤后60h及72 h较48 h降低.肺挫伤组PAWP开始较对照组降低,于伤后48 h恢复至对照组水平;对照组自置管即刻至伤后72 h无显著变化.相关性分析显示,挫伤组置管即刻至伤后48 h,PAS、PAD、PAD-PAWP与ELWI均呈正相关(r值分别为0.554、0.498、0.629,均P＜0.01).结论 PAS、PAD、PAD-PAWP和ELWI的变化规律可指导肺挫伤致ARDS患者的液体治疗、机械通气和评估病情.     

急性肺损伤兔改良肺部超声评分与血气变化的相关性

目的 通过复制盐酸所致急性肺损伤动物模型,探讨改良肺部超声评分法(MLUS)与氧合指数PaO2/FiO2的相关性。     

急性肺损伤肺保护性通气乌司他丁干预的临床研究

目的 评价肺保护性通气乌司他丁干预在控制急性肺损伤（ALI）和防治多器官功能障碍综合征（MODS）及降低其病死率中的作用。方法57例ALI患者随机分为肺保护性通气组（n=28）和肺保护性通气乌司他丁干预组（n=29），比较两组患者呼吸力学、动脉血气及血流动力学的变化，观察两组患者肺及肺外器官功能改善率、机械通气并发症发生率、ICU病死率及其死亡的原因等。结果两组患者的年龄和APACHEⅡ评分比较差异无显著性（P〉0.05）；肺保护性通气乌司他丁干预组对ALI患者的呼吸力学、动脉血气及血流动力学的影响均优于肺保护性通气组；肺保护性通气乌司他丁干预组对肺及肺外器官功能改善率明显优于肺保护性通气组，另外，机械通气所致肺损伤的发生率、机械通气相关心肌缺血和心律失常的发生率也均明显下降；肺保护性通气乌司他丁干预组因多器官功能衰竭（MOF）的ICU病死率为20．69％，明显优于肺保护性通气组（46．43％，P〈0．05）。结论肺保护性通气乌司他丁干预能改善ALI患者的呼吸力学、动脉血气及血流动力学，能降低其呼吸机所致肺损伤（VILI）、机械通气相关心肌缺血和心律失常的发生率，在防治MODS及降低ALI患者病死率上有显著的临床效果。     

Inhaled milrinone attenuates experimental acute lung injury

Purpose  To test whether inhalation of the phosphodiesterase 3 inhibitor milrinone may attenuate experimental acute lung injury (ALI). Methods  In rats, ALI was induced by infusion of oleic acid (OA). After 30 min, milrinone was inhaled either as single dose, or repeatedly in 30 min intervals. In mice, ALI was induced by intratracheal instillation of hydrochloric acid, followed by a single milrinone inhalation. Results  Four hours after OA infusion, ALI was evident as lung inflammation, protein-rich edema and hypoxemia. A single inhalation of milrinone attenuated the increase in lung wet-to-dry weight ratio and myeloperoxidase activity, and reduced protein concentration, neutrophil counts and TNF-α levels in bronchoalveolar lavage. This effect was further pronounced when milrinone was repeatedly inhaled. In mice with acid-induced ALI, milrinone attenuated hypoxemia and prevented the increase in lung myeloperoxidase activity. Conclusions  Inhalation of aerosolized milrinone may present a novel therapeutic strategy for the treatment of ALI.     

肺部加强护理在重症急性胰腺炎合并急性肺损伤患者中的实施与效果评价

目的探讨重症急性胰腺炎（SAP）合并急性肺损伤（ALI）患者肺部护理的有效方法。方法将2005年1月-2006年12月收入我科ICU的SAP患者205例，分为加强组114例：2006年1—12月收治，采用肺部加强护理的方法，在常规肺部护理的基础上，采用针对性叩背、肺部震颤、喷射式雾化吸入、持续加温湿化氧疗等肺部护理手段；常规组91例：2005年1—12月年收治，采用以往常规肺部护理方法即鼓励患者深呼吸运动、咳嗽、帮助排痰、氧疗、超声雾化吸入等。结果与2005年相比，2006年的肺部加强护理方法显著降低了重症急性胰腺炎合并急性肺损伤患者的气管插管率，显著缩短了人工气道的使用时间及住SICU时间，提高了治愈率，P〈0．05。结论肺部加强护理是重症胰腺炎合并急性肺损伤患者肺部护理的有效方法。     

PEEP decreases atelectasis and extravascular lung water but not lung tissue volume in surfactant-washout lung injury

Objective To examine the effects of positive end-expiratory pressure (PEEP) on extravascular lung water (EVLW), lung tissue, and lung volume.Design and setting Experimental animal study at a university research facility.Subjects Fifteen adult sheep.Interventions All animals were studied before and after saline washout-induced lung injury while ventilated with sequentially increasing PEEP (0, 7, 14, or 21 cmH₂O).Measurements and results Lung volume was determined by computed tomography and EVLW by the thermal dye dilution technique. Saline washout significantly increased lung tissue volume (21±3 to 37±5 ml/kg) and EVLW (9±2 to 36±9 ml/kg). While increasing levels of PEEP reduced EVLW (30±7, 24±8, and 18±4 ml/kg), lung tissue volume remained constant. Total lung volume significantly increased (50±8 ml/kg at PEEP 0 to 77±12 ml/kg at PEEP 21). Nonaerated lung volume significantly decreased and was closely correlated with the changes in EVLW (r=0.67). In addition, a highly significant correlation was found between PEEP-induced decrease in nonaerated lung volume and decrease in transpulmonary shunt (r=0.83).Conclusions The main findings are as follows: (a) PEEP effectively decreases EVLW. (b) The decrease in EVLW is closely correlated with the PEEP-induced decrease in nonaerated lung volume, making EVLW a valuable bedside parameter indicating alveolar recruitment, similar to measurements of transpulmonary shunt. (c) As excess tissue volume remained constant, however, EVLW may not be suitable to reflect overall severity of lung diseaseThis study was supported by a grant from the Faculty of Clinical Medicine, University of Mannheim.     

地塞米松对海水淹溺性肺损伤兔肺水肿吸收的影响

目的探讨地塞米松对海水淹溺性肺损伤兔的肺泡钠水转运系统及肺水肿的影响。方法新西兰兔随机分成对照组(CG)和地塞米松治疗组(BG)。CG兔(n=12)的气管内灌注4 ml/kg海水,DG兔(n=12)在CG的基础上静注1 mg/kg地塞米松。肺水肿用血管外肺水含量指数(EVLWI)监测。给药3 h收集肺组织标本,分别用RT-PCR和Western印迹检测肺组织中钠离子通道-α亚单位mRNA(α-ENaC mRNA)和钠钾泵-α1亚单位(NKA-α1)蛋白的丰度以及水解法检测NKA活性。结果DG的EVLWI显著的低于CG[(0．508±0．089)vs．(0．648±0．102),P＜0．05],而α-ENaC mRNA和NKA-α1蛋白的丰度均显著的高于相应的CG(P＜0．05,P＜0．05),NKA活性也显著的高于CG(P＜0．05)。结论地塞米松可增加肺泡钠水转运系统的表达或活性,并减轻海水灌注肺损伤兔的肺水肿。     

细胞因子和水钠通道蛋白在急性肾损伤致肺损伤中的作用

目的 通过双肾动静脉夹闭建立急性缺血性肾损伤大鼠模型,观察大鼠肺病理生理的变化,观察上皮细胞钠通道蛋白(α-ENaC)和水通道蛋白1(AQP1)在急性肾损伤所致肺损伤中的作用.方法 健康雄性Wistar大鼠60只.体质量300～ 320 g,随机(随机数字法)分成健康对照组(A组),急性肾损伤组(B组),每组30只.造模后,处死大鼠,苏木素伊红(HE)染色检查肺组织病理变化,计算肺W/D比值,支气管肺泡灌洗液(BALF)中蛋白质量浓度.检测肺组织中水通道蛋白1、肺上皮钠通道蛋白的质量浓度.测定血清及BALF中IL-6与TNF-α的质量浓度.结果 B组大鼠在实验后6h动脉血pH值开始下降,酸中毒逐渐加重,与A组比较差异具有统计学意义(P＜0.05).B组与A组的氧分压各时间点之间相比差异无统计学意义(P＞0.05).与A组相比,B组在实验后2h肺泡灌洗液中蛋白水平、肺W/D值开始明显增加,差异具有统计学意义(P＜0.05).B组实验后8h肺泡上皮肿胀,肺泡壁增宽,肺泡间质水肿明显,肺泡内可见炎症细胞、红细胞和蛋白渗出,表现出急性肺损伤的病理改变.B组在实验后2h血清及肺泡灌洗液中TNF-、IL-6的质量浓度开始增加,肺组织中AQP1、α-ENaC表达开始逐渐减少,与A组比较,差异具有统计学意义(P＜0.05).结论 急性肾损伤早期肺泡上皮-内皮屏障功能已经受到了影响,急性肺损伤已经发生.急性肾损伤后早期体内TNF-α、IL-6含量明显增加,肺表达AQP1及α-ENaC的减少,可能是急性肾损伤早期引起肺损伤的原因之一.     

Effect of N-acetylcysteine (NAC) on acute lung injury and acute kidney injury in hemorrhagic shock

Aim of the study

N-acetylcysteine (NAC) has been investigated to attenuate organ injury in various experimental and clinical studies. However, results in hemorrhagic shock (HS) were controversial. We determined the effects of continuous administration of NAC on acute lung injury (ALI) and acute kidney injury (AKI) in HS model.

Methods

Twenty male Sprague-Dawley rats were used. Pressure controlled HS model defined by mean arterial pressure (MAP) 40 ± 2 mmHg for 90 min followed by resuscitation and observation was used. Rats (n = 10 per group) were randomized into 2 groups with NAC or dextrose. Intravenous NAC was given continuously from 15 min after induction of HS to the end of observation period (2 h). We measured serum IL-6, nitrite/nitrate concentration. NF-κB p65 DNA binding activity, expressions of cytoplasmic phosphorylated IκB-α (p-IκB-α) and IκB-α, malondialdehyde (MDA) and histopathological injury scores in lung and kidney were also evaluated.

Results

MAP did not show any difference during the study period. NAC decreased histopathologic scores in both lung and kidney. Lung and kidney MDA levels were significantly lower in the NAC group compared to control group. Serum nitrite/nitrate and IL-6 were also significantly lower in the NAC group. The levels of lung cytoplasmic p-IκB-α expression was mitigated by NAC, and NF-κB p65 DNA binding activity was also significantly decreased in the NAC group.

Conclusions

Continuous infusion of NAC attenuated inflammatory response and acute lung and kidney injury after hemorrhagic shock in rats.     

Lung ultrasound findings in hospitalized COVID-19 patients in relation to venous thromboembolic events: the ECHOVID-19 study

PurposeSeveral studies have reported thromboembolic events to be common in severe COVID-19 cases. We sought to investigate the relationship between lung ultrasound (LUS) findings in hospitalized COVID-19 patients and the development of venous thromboembolic events (VTE).MethodsA total of 203 adults were included from a COVID-19 ward in this prospective multi-center study (mean age 68.6 years, 56.7% men). All patients underwent 8-zone LUS, and all ultrasound images were analyzed off-line blinded. Several LUS findings were investigated (total number of B-lines, B-line score, and LUS-scores).ResultsMedian time from admission to LUS examination was 4 days (IQR: 2, 8). The median number of B-lines was 12 (IQR: 8, 18), and 44 (21.7%) had a positive B-line score. During hospitalization, 17 patients developed VTE (4 deep-vein thrombosis, 15 pulmonary embolism), 12 following and 5 prior to LUS. In fully adjusted multivariable Cox models (excluding participants with VTE prior to LUS), all LUS parameters were significantly associated with VTE (total number of B-lines: HR = 1.14, 95% CI (1.03, 1.26) per 1 B-line increase), positive B-line score: HR = 9.79, 95% CI (1.87, 51.35), and LUS-score: HR = 1.51, 95% CI (1.10, 2.07), per 1-point increase). The B-line score and LUS-score remained significantly associated with VTE in sensitivity analyses.ConclusionIn hospitalized COVID-19 patients, pathological LUS findings were common, and the total number of B-lines, B-line score, and LUS-score were all associated with VTE. These findings indicate that the LUS examination may be useful in risk stratification and the clinical management of COVID-19. These findings should be considered hypothesis generating.Clinicaltrials.gov ID{"type":"clinical-trial","attrs":{"text":"NCT04377035","term_id":"NCT04377035"}}NCT04377035