ARDS after double extrinsic exposure hypersensitivity pneumonitis

Hypersensitivity pneumonitis or extrinsic allergic alveolitis is a lung disease due to T cell and macrophage activation with IgA, IgG or IgE immunocomplex tissue lesions following extrinsic exposure to organic or inorganic agents. We report a case of hypersensitivity pneumonitis (pigeon protein sensitized) with a second nosocomial exposure to Aspergillus fumigatus proteins from a contaminated oxygen water humidifier: the second extrinsic exposure induced significant acute respiratory failure with ARDS. A pre-existing COPD syndrome requiring prolonged oxygen therapy (7 days) involved lung disease with delayed clinical diagnosis and therapy. Microbiological and mycological analysis of oxygen water humidifiers should be considered, especially for hypersensitivity pneumonitis patients, when a new inexplicable clinical impairment occurs. Received: 17 November 1998 Final revision received: 23 March 1999 Accepted: 30 April 1999     

8例吸入性肺炎患者合并ARDS的救治与护理

急性呼吸窘迫综合征（ARDS）系各种病因引起的肺脏内血管与组织间液体交换功能紊乱，导致肺含水量增加，肺顺应性降低，肺泡萎缩，通气血流比例失调的一种以进行性呼吸困难和顽固性低氧血症为特征的急性呼吸衰竭^[1]。本病起病急骤、发展快、病死率高。常见致病因素有休克、创伤、误吸、肺内或肺外的感染等^[2]。     

丹参对ARDS大鼠肺损伤的治疗保护和对肺泡巨噬细胞分泌细胞因子的调节作用

目的了解丹参对大鼠血气改变和肺系数的影响以及丹参对肺泡巨噬细胞分泌肿瘤坏死因子(TNF a)、白介素-1(IL-1)的调节作用.方法静注油酸制造ARDS大鼠模型为油酸组,静注生理盐水作对照组,静注油酸同时以丹参灌胃为治疗组.静注油酸及生理盐水6小时后,测定左心PaO2、PaCO2及肺系数.分离培养各组大鼠肺泡巨噬细胞,采用MTT法测定TNF a、IL-1.结果油酸组PaO2值明显低于对照组和治疗组,而PaCO2值明显高于对照组和治疗组(P＜0.001).治疗组血气明显好于油酸组(P＜0.05).油酸组肺系数(1.03±0.06)高于治疗组(0.72±0.05)和对照组(0.64±0.06),P＜0.01.TNF a、IL-1分别为油酸组(72.06±5.64)%、(96.22±11.61)U/ml,对照组(7.75±1.05)%、(21.05±3.11)U/ml,治疗组(35.44±4.55)%、(70.66±8.23)U/ml.油酸组分泌TNFa、IL-1的水平显著高于对照组(P＜0.001),治疗组亦显著高于对照组,但明显低于油酸组(P＜0.001).结论丹参对ARDS有保护性治疗作用,对ARDS大鼠肺泡巨噬细胞过度活化、分泌TNF a、IL-1具有抑制作用.研究对肺泡巨噬细胞分泌细胞因子的调节作用对认识ARDS的发病机制和指导临床治疗有重要意义.     

What is normal intra-abdominal pressure and how is it affected by positioning, body mass and positive end-expiratory pressure?

Purpose  To describe what is defined as normal intra-abdominal pressure (IAP) and how body positioning, body mass index (BMI) and positive end-expiratory pressure (PEEP) affect IAP monitoring. Methods  A review of different databases was made (Pubmed, MEDLINE (January 1966–June 2007) and EMBASE.com (January 1966–June 2007)) using the search terms of “IAP”, “intra-abdominal hypertension” (IAH), “abdominal compartment syndrome” (ACS), “body positioning”, “prone positioning”, “PEEP” and “acute respiratory distress syndrome” (ARDS). Prior to 1966, we selected older articles by looking at the reference lists displayed in the more recent papers. Results  This review focuses on the concept that the abdomen truly behaves as a hydraulic system. The definitions of a normal IAP in the general patient population and morbidly obese patients are reviewed. Subsequently, factors that affect the accuracy of IAP monitoring, i.e., body position (head of bed elevation, lateral decubitus and prone position) and PEEP, are explored. Conclusion  The abdomen behaves as a hydraulic system with a normal IAP of about 5–7 mmHg, and with higher baseline levels in morbidly obese patients of about 9–14 mmHg. Measuring IAP via the bladder in the supine position is still the accepted standard method, but in patients in the semi-recumbent position (head of the bed elevated to 30° and 45°), the IAP on average is 4 and 9 mmHg, respectively, higher. Future research should be focused on developing and validating predictive equations to correct for supine IAP towards the semi-recumbent position. Small increases in IAP in stable patients without IAH, turned prone, have no detrimental effects. The role of prone positioning in the unstable patient with or without IAH still needs to be established.     

颅脑损伤合并呼吸窘迫综合征诊断

颅脑损伤后呼吸窘迫综合征（ARDS）的发病率仅次于肺损伤居第2位 。本病病死率高达35%~85%[2]。针对如何降低病死率,正确的早期诊断及治疗尤为重要。衡水市第四医院神经外科1998至2002年收治该病30例,报告如下。1临床资料1.1一般资料男18例,女12例;年龄18~68岁,平均年龄38岁。致伤原因：交通事故18例,坠落伤6例,头部钝器伤5例,其它1例。损伤类型：广泛性脑挫裂伤10例,颅内血肿5例,     

扶正祛邪中药对急性呼吸窘迫综合征模型大鼠影响研究

目的：观察扶正祛邪中药对急性呼吸窘迫综合征（ARDS）模型大鼠的影响。方法：WISTAR大鼠18只，随机分为3组各6只，空白组尾静脉注射生理盐水，模型组及中药组注射油酸（OA）复制模型，然后分别灌服生理盐水、ARDS5号方灌胃2次，24h后观察各组肺组织病理学变化。结果：肺组织病理学形炎积分空白组为0分，模型组为（2．67±0．516）分，中药组为（1．50±0．837）分。中药组与模型组比较有显著性差异（P〈0．05）。结论：扶正祛邪中药可改变OA型ARDS大鼠肺组织损伤。     

参麦注射液防治兔油酸型急性呼吸窘迫综合征的实验研究

目的：观察静注参麦注射液对实验性油酸型急性呼吸窘迫综合征（ＡＲＤＳ）的影响。方法：静脉注射油酸（０．１ｍｌ／ｋｇ）复制家兔ＡＲＤＳ的动物模型，随后立即静脉注射参麦注射液（１０ｍｌ／ｋｇ），观察在ＡＲＤＳ发展过程中白细胞介素－１（ＩＬ－１）、肿瘤坏死因子（ＴＮＦ）、血气，２ｈ后处死动物检测肺组织匀浆ＩＬ－１、ＴＮＦ活性及病理改变，并与模型组做比较。结果：参麦注射液可明显缓解油酸所致的急性肺损伤，改善低氧血症，经统计学处理后治疗组与模型组相比，血浆ＩＬ－１，ＴＮＦ在１２０ｍｉｎ（Ｐ＜０．０５），肺组织匀浆ＩＬ－１、ＴＮＦ治疗组与模型组相比较亦降低（Ｐ＜０．０５）。结论：提示参麦注射液可明显减轻所致的急性肺损伤，对防治ＡＲＤＳ有一定的作用     

急性呼吸窘迫综合征早期肺循环细胞学和生化改变的初步研究

给大鼠静脉注射油酸制备实验性急性呼吸窘迫综合征（ＡＲＤＳ）模型。在ＡＲＤＳ发生的早期，用肺动脉导管（ＰＡＣ）从肺小动脉中动态取血，发现肺动脉（ＰＡ）血中白细胞（ＷＢＣ）和血管紧张素Ⅰ转换酶（ＡＣＥ）活性在注射油酸后很快升高，并与肺水肿、血氧分压（ＰａＯ２）有明显相关关系（Ｐ＜０．００１）；ＰＡ血中ＷＢＣ数与股动脉（ＦＡ）血中ＷＢＣ数无明显关系（Ｐ＞０．０５）；而ＰＡ血中ＡＣＥ活性与ＦＡ血中ＡＣＥ活性有明显相关关系（Ｐ＜０．００１）。结果表明，用外周血ＷＢＣ数不能反映肺内的改变；外周血中ＡＣＥ活性的变化可以用于估计肺损伤的情况，因此，对临床ＡＲＤＳ的早期诊断可能有重要的参考价值。     

保护性通气策略治疗ARDS的临床研究

目的探讨应用保护性通气策略的机械通气治疗ARDS效果.方法使用呼吸机小潮气量与肺开放策略(参数VT4.8～8.0 ml/kg、PSV12～16 cm H2O、PEEP 5～13 cm H2O、RR18～20次/min,维持气压峰压<50 cm H2O,平台压<35 cm H2O,峰值流速18～20 L/min),治疗ARDS 27例.结果 27例机械通气时间28～168.7 h,治愈出院21例,死亡6例,死亡率26.1%,未出现气压伤现象,出现呼吸机相关肺炎3例.结论 ARDS的机械通气方法采用个体化保护性通气策略,其治愈率高,死亡率低,并发症少,个体化保护性通气策略应该普遍推广应用,提高ARDS抢救成功率.     

Oxygen radicals and lung injury

This article describes the formation of oxygen radicals and their biological effects, especially in relation to lung injury. Various recent experimental data are reviewed. The relationships between hydrostatic effects and permeability effects in producing injury and edema are stressed. Means of prevention and problems related to extrapolation to clinical situations are focused.