可溶性髓系细胞触发受体-1在支气管肺泡灌洗液及呼出气冷凝液中的表达对呼吸机相关性肺炎的诊断价值研究

目的:探讨支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)及呼出气冷凝液(exhaled breath condensate,EBC)中的可溶性髓系细胞触发受体-1(soluble triggering receptor expressed on myeloid cells 1,sTREM-1)含量,以及其在呼吸机相关性肺炎(ventilator-associated pneumonia,VAP)诊断中的价值。方法:纳入2014年3所教学医院中疑似VAP的患者127例,于疑诊VAP当日及诊断VAP当日行纤维支气管镜肺泡灌洗,并检测BALF及EBC中s TREM-1的含量,经受试者工作特征(receiver operating characteristic,ROC)曲线选取最佳临界值,评估其诊断效价。结果:127例疑似VAP的患者中72例(56.69%)被诊断为VAP。于诊断当日检测VAP及非VAP患者BALF中的s TREM-1含量为58.06 pg/m L[四分位数间距(interquartile range,IOR)为40.45~70.71 pg/m L]和16.69 pg/m L(IOR为13.24~33.07 pg/m L),而两者EBC中的s TREM-1含量分别为1.97 pg/m L(IOR为1.54~2.61 pg/m L)和0.56 pg/m L(IOR为0.26~1.59 pg/m L),比较发现,VAP患者BALF及EBC中的s TREM-1含量均高于非VAP患者(P<0.001)。结论:BALF及EBC中的sTREM-1含量对于VAP的诊断准确率较高,值得临床推广。     

微支气管肺泡灌洗液可溶性髓细胞触发受体对呼吸机相关性肺炎早期诊断价值

目的 探讨采用微支气管肺泡灌洗技术获得支气管肺泡灌洗液中可溶性髓系细胞触发受体-1(sTREM-1)表达对呼吸机相关性肺炎早期诊断价值.方法 对112例在机械通气前无肺部感染,行机械通气48 h后出现发热、气管支气管内分泌物增多脓性,临床疑诊VAP患者,通过微支气管肺泡灌洗技术获取BALF液体,测定BALF中sTREM-1、血清CRP水平及临床肺部感染积分(CPIS).应用受试者工作特征(ROC)曲线来分析上述指标对VAP的诊断价值.结果 与非VAP患者比较,VAP患者在临床疑诊当天BALF中sTREM-1、血清CRP水平及CPIS评分明显升高(P＜0.01).行ROC曲线分析,显示BALF中sTREM-1水平153.18 pg/mL时诊断VAP有最佳的敏感性和特异性,分别为86.49％和84.21％,ROC曲线下面积为0.882,诊断价值优于血清CRP和CPIS(ROC曲线下面积分别为0.723和0.823).结论 BALF中sTREM-1水平＞ 153.18 pg/mL时,有利于早期诊断VAP.     

胰石蛋白在呼吸机相关性肺炎患者支气管肺泡灌洗液及呼出气冷凝液中的表达及检测价值

目的观察胰石蛋白(PSP)在呼吸机相关性肺炎(VAP)患者支气管肺泡灌洗液(BALF)及呼出气冷凝液(EBC)中的表达并探讨其检测价值。方法采用酶联免疫吸附法(ELISA)分别检测40例VAP患者VAP疑诊当日及VAP诊断当日BALF、EBC中的PSP表达水平,同期选择40例行机械通气治疗而未出现VAP的患者作为对照组。比较2组患者不同时点BALF、EBC中PSP表达水平,采用受试者工作特征(ROC)曲线法分析BALF、EBC中PSP水平检测对VAP的诊断价值。结果VAP组患者疑诊当日、诊断当日的BALF、EBC中PSP表达水平均显著高于对照组(P 0. 05),2组患者VAP诊断当日的BALF、EBC中PSP表达水平均显著高于VAP疑诊当日(P 0. 05),2组患者同时点的BALF中PSP表达水平均显著高于EBC(P 0. 05); VAP诊断当日BALF中PSP的曲线下面积为0. 91,高于VAP诊断当日EBC中PSP和VAP疑诊当日BALF、EBC中PSP的曲线下面积,虽然灵敏度(87. 50%)低于EBC中PSP(92. 50%),但特异度(80. 00%)高于EBC中PSP(67. 50%)。结论检测BALF、EBC中PSP水平对于VAP早期诊断具有较高的临床价值,尤其是BALF中PSP水平检测的价值更高。     

可溶性髓系细胞触发受体-1对呼吸机相关肺炎早期诊断及预后的判断价值

目的探讨血清及呼出气冷凝液（EVC）中可溶性髓系细胞触发受体-1（sTREM1）对呼吸机相关性肺炎（VAP）早期诊断及预后判断的临床价值。方法对37例机械通气患者进行治疗后评估,分成非感染组13例,感染组24例（其中治疗有效组14例,治疗无效组10例）,所有患者均在机械通气后第1、3、5、7天应用双抗体夹心酶联免疫吸附法（DAS-ELISA）测定血清和EVC中sTREM-1水平,并记录下呼吸道分泌物细菌培养结果和患者治疗后转归;应用受试者工作特征曲线（ROC）研究sTREM-1对VAP早期诊断效能及预后判断价值。结果第1天,血清及EVC中sTREM-1水平治疗有效组、治疗无效组及非感染组比较,差异无统计学意义（P〉0．05）;第3天和第5天,感染组较非感染组有明显升高（P〈（J．01）;第7天,治疗无效组仍处较高水平,与治疗有效组、非感染组比较差异有统计学意义（P〈0．01）,而治疗有效组与非感染组比较差异无统计学意义（P〉0．05）。应用ROC分析,第3天血清和EVC中sTREM-1曲线下面积分别为0．897、0．909。以第3天EVC中sTREM-14．70ng／mL为VAP的早期诊断界值,其诊断灵敏度为95．8％,特异度为92．3％。结论血清和EVC中sTREM-1检测有助于VAP的早期诊断,第7天血清和EVC中sTREM-1水平有助于判断VAP的预后（撤机失败和死亡）,与血清标本比较,EVC的获得更加方便。     

纤维支气管镜吸痰联合肺泡灌洗治疗呼吸机相关性肺炎

目的:探究纤维支气管镜吸痰联合肺泡灌洗在呼吸机相关性肺炎治疗中的应用效果。方法:选取我院2016年5月～2017年8月收治的82例呼吸机相关性肺炎(VAP)患者作为研究对象,随机分为治疗组和对照组,每组41例,对照组采用常规治疗,治疗组在对照组的基础上加用纤维支气管镜吸痰联合肺泡灌洗进行治疗,比较两组患者肺部感染指数(CPIS)评分、治疗前后的PCT、CRP和IL-6等炎症指标及PaO_2、SaO_2和PaO_2/FIO2等呼吸动力学指标。结果:治疗前,两组的CPIS评分相比较,差异无统计学意义,P0.05;治疗后,治疗组的CPIS评分均明显低于对照组,差异有统计学意义,P0.05;治疗前,两组PCT、CRP和IL-6水平相比较,差异无统计学意义,P0.05;治疗后,治疗组的PCT、CRP和IL-6水平均明显低于对照组,差异有统计学意义,P0.05;治疗前,两组的PaO_2、SaO_2和PaO_2/FIO2等指标相比较,差异无统计学意义,P0.05;治疗后,治疗组的PaO_2、SaO_2和PaO_2/FIO2等指标均明显高于对照组,差异有统计学意义,P0.05。结论:采用纤维支气管镜吸痰联合肺泡灌洗治疗VAP患者,能降低患者的CPIS评分和炎性因子水平,改善呼吸动力学指标,获得良好的疗效。     

纤维支气管镜肺泡灌洗在呼吸机相关性肺炎中的应用及护理

随着ICU机械通气的普及，呼吸机相关性肺炎（ventilator associated pneumonia，VAP），已成为机械通气患者常见的严重并发症，是导致机械通气失败的第一位原因。我科2004年6月～2006年12月对32例呼吸机相关性肺炎患者采用床边纤维支气管镜、支气管肺泡灌洗加局部注入抗生素的治疗方法，由于护理得当，均取得了满意的治疗效果，现报道如下。     

呼吸机相关性肺炎诊断的研究进展

随着呼吸机和现代医疗技术的不断提高．呼吸机辅助机械通气的应用为各种原因所致的呼吸衰竭患者提供了广阔的治疗前景,为成千上万的患者赢得第二次生命。但不少患者因呼吸机相关肺炎（ventilator-associated pneumonia, VAP）的发生及未能有效控制而死亡。VAP是患者接受机械通气48h后并发的肺部感染。     

纤维支气管镜肺泡灌洗对呼吸机相关性肺炎危重患者的临床疗效

目的分析纤维支气管镜肺泡灌洗治疗重症加强护理病房(ICU)呼吸机相关性肺炎危重患者的疗效及对血气指标和炎症指标的影响。方法选择在该院接受住院治疗的ICU呼吸机相关性肺炎危重患者作为研究对象,随机分为接受常规治疗的对照组,接受纤维支气管镜肺泡灌洗治疗的观察组,比较两组患者的治疗前后呼吸功能、血气水平及炎症因子水平等差异。结果观察组患者接受治疗后的气道峰压(PIP)值和气道阻力(RAW)值低于对照组患者,肺动态顺应性(CD)值高于对照组患者(P0.05)。观察组患者接受治疗后的Pa O2和Pa O2/Fi O2水平高于对照组患者,Pa CO2水平低于对照组患者(P0.05)。观察组患者接受治疗后的血清IL-8、CRP和PCT等指标值均明显低于对照组患者(P0.05)。结论纤维支气管镜肺泡灌洗可以有效改善ICU呼吸机相关性肺炎危重患者的呼吸功能及血气水平,降低全身炎症因子水平。     

sTREM-1在诊断呼吸机相关性肺炎中的临床价值

目的:研究机械通气患者经气管导管抽吸物(EA)中可溶性髓系细胞表达触发受体-1(sTREM-1)预测呼吸机相关性肺炎(VAP)的诊断价值。方法:采用回顾性诊断方法,纳入2010年3月至2011年3月间在我院确诊VAP的44例患者作为研究对象,其中重症VAP28例,同时设对照组23例,测定抗生素治疗前EA中sTREM-1、血清CRP、IL-6,并计算CPIS评分。结果:VAP患者EA中sTREM-1、血清中CRP、IL-6和CPIS评分均显著高于非VAP组(均P<0.05),且重症VAP组EA中sTREM-1、血清中CRP、IL-6和CPIS评分显著高于非重症VAP组(均P<0.05)。做受试者工作特征曲线(ROC)分析,预测VAP时,EA中sTREM-1﹥68.7pg/mL的敏感性及特异性分别为81.8%和87.0%,预测重症VAP时,EA中sTREM-1﹥109.3pg/mL的敏感性及特异性分别为89.3%和87.5%,较CRP、IL-6及CPIS的敏感性及特异性高。结论:EA中sTREM-1浓度可作为VAP早期诊断的有效指标,其亦可作为预测重症VAP的指标,可与其他炎症因子联合检测,以提高对VAP及重症VAP的早期诊断率。     

以支气管肺泡灌洗液的内毒素诊断革兰阴性菌肺炎

目的：阐明鲎细胞溶解物试验（ＬＡＬ）检测支气管肺泡灌洗液（ＢＡＬＦ）在诊断革兰阴性杆菌肺炎中的作用。方法：ＬＡＬ测定采用半定量法。ＢＡＬＦ经纤维支气管镜导管法采集。结果：１０例经细菌学确诊患者ＢＡＬＦ内毒素水平均大于１∶１６。细菌学确定的革兰阴性菌肺炎与ＢＡＬＦ内毒素大于或等于１∶１６阳性之间总符合率为９０％（Ｋａｐｐａ系数０．６７）。经细菌学确诊的阴性菌肺炎组ＢＡＬＦ内毒素单位（ＥＵ）为１２．５×１０３ＥＵ／Ｌ,无肺炎组为１．８×１０３ＥＵ／Ｌ,差异有显著性（Ｐ＜０．０１）。结论：以ＬＡＬ检测ＢＡＬＦ为诊断阴性菌肺炎的一种快速、准确、简便的试验方法。     

High levels of sulfated mucins in bronchoalveolar lavage fluid of ICU patients with ventilator-associated pneumonia

OBJECTIVE: To compare the levels of sulfated mucins in bronchoalveolar lavage fluid (BALF) in ICU patients with ventilator-associated pneumonia (VAP) with those in non-infectious controls, i.e., ventilated ICU patients without VAP, and nonventilated patients. DESIGN AND SETTING: Prospective study in a mixed intensive care unit and outpatient clinic of a university hospital. PATIENTS: The study included 56 ventilated ICU patients with VAP, 21 ventilated ICU patients without VAP, and 26 nonventilated outpatients with no pulmonary infection. MEASUREMENTS AND RESULTS: Total cell count and differential cell count of BALF samples were determined, and sulfated mucin levels were measured. For this we used the monoclonal antibody F2 against the sulfated Lewis C structure (SO(3)-3Galbeta1-3GlcNAc). Sulfated mucin levels were significantly increased in ICU patients with VAP than in those without VAP and nonventilated patients. No statistical difference was found between the two groups of ICU patients regarding APACHE II score and the duration of mechanical ventilation prior to the bronchoalveolar lavage. CONCLUSIONS: The increased levels of sulfated mucins in ICU patients with VAP are associated with infection and not with ventilation. The increase in sulfated mucins may favor the persistence of those micro-organisms that possess mucin sulfatase activity, which enable them to survive within the mucus, especially Pseudomonas aeruginosa.     

Variation of infected cell count in bronchoalveolar lavage and timing of ventilator-associated pneumonia

Objectives The aim of this study was to evaluate and compare the accuracy of the percentage of infected cells (%IC) in bronchoalveolar lavage (BAL) for ventilator-associated pneumonia (VAP) diagnosis according to its onset from the initiation of mechanical ventilation.Patients One hundred and eight patients admitted to a surgical ICU were retrospectively included (1999–2001). A total of 171 cases of VAP were diagnosed on clinical, biological, chest X-ray and BAL results (threshold 10⁴ cfu/ml).Results The %IC significantly decreased with the timing of VAP diagnosis: 12.2±12.1% for VAP occurring less than 7 days after the initiation of mechanical ventilation, 7.4±9.2% for VAP occurring between 7 and 15 days and 4.8±6.4% for VAP after 15 days (p=0.0002), despite the same number of elements and proportion of polymorphonuclear neutrophils in BAL. In addition, a relationship between the %IC and the pathogen responsible for VAP was observed for P. aeruginosa [higher for VAP <7 days than for VAP 7–15 days (p=0.01) and VAP >15 days (p=0.006)] and S. aureus [lower for VAP >15 days than VAP 7–15 days (p=0.04) and VAP <7 days (p=0.04)]. Furthermore, the %IC in BAL was lower in patients undergoing antimicrobial therapy than in patients without antibiotics (p=0.04). Three factors were independently associated with the %IC: quantitative culture of BAL (=0.42, p<0.0001), ongoing antimicrobial therapy (= –0.21, p=0.003) and onset of VAP (= –0.17, p=0.01).Conclusions A relationship between the %IC in BAL, duration of ventilation, quantitative culture of BAL and ongoing antimicrobial therapy has been proved in this study. The %IC for VAP diagnosis may not be accurate in patients with ongoing antibiotics and late onset infections (>7 days).Presented in part at the annual meeting of the European Society of Intensive Care Medicine, Barcelona, Spain, 29th September to 2nd October, 2002.     

生物标志物联合检测在早期糖尿病肾病诊断中的应用

目的探讨血清肌酐(SCr)、血尿素(Sur)、血清胱抑素C(CysC)、中性粒细胞明胶酶相关脂质运载蛋白(NGAL)及C1q联合检测用于早期糖尿病肾病辅助诊断的临床价值。方法回顾性分析十堰市太和医院2018年收治的单纯糖尿病患者50例、早期糖尿病肾病患者65例及健康体检者150例的临床资料,均行SCr、Sur、CysC、NGAL及C1q检测,计算以上指标单项和联合检测用于早期糖尿病肾病的诊断效能,并采用单因素方差分析比较组间差异。结果早期糖尿病肾病患者男性比例、年龄、Sur水平、SCr水平、CysC水平、尿微量清蛋白与尿肌酐比值(UACR)、C1q水平及NGAL水平均明显高于单纯糖尿病患者和健康体检者,差异均有统计学意义(P<0.05);早期糖尿病肾病患者肾小球滤过率明显低于单纯糖尿病患者和健康体检者,差异均有统计学意义(P<0.05)。相关指标单项检测时,CysC诊断效能最高,Sur最低,其中CysC诊断效能明显高于C1q、NGAL、SCr及Sur,差异均有统计学意义(P<0.05)。相关指标2项联合检测时,C1q+CysC诊断效能最高,SCr+NGAL最低,C1q+CysC诊断效能均明显高于其他组合,差异均有统计学意义(P<0.05);而CysC+NGAL、SCr+C1q及C1q+NGAL明显高于SCr+NGAL、SCr+CysC,差异均有统计学意义(P<0.05)。相关指标3项联合检测时,C1q+CysC+NGAL诊断效能最高,SCr+NGAL+CysC最低;C1q+CysC+NGAL、C1q+CysC+SCr及SCr+C1q+NGAL诊断效能明显高于SCr+NGAL+CysC,差异均有统计学意义(P<0.05)。C1q+NGAL+CysC+SCr检测较其他组合诊断效能均高,但C1q+NGAL+CysC+SCr、C1q+CysC+NGAL、SCr+C1q+CysC及CysC+C1q的诊断效能组间比较差异均无统计学意义(P>0.05),且CysC+C1q诊断特异度较C1q+NGAL+CysC+SCr更高。结论 C1q、CysC及NGAL用于早期糖尿病肾病的辅助诊断价值优于SCr、Sur,且C1q联合CysC检测应用诊断效能更佳。     

Soluble Triggering Receptor Expressed on Myeloid cells-1 in bronchoalveolar lavage fluid is not predictive for ventilator-associated pneumonia

Purpose  Soluble Triggering Receptor Expressed on Myeloid cells-1 (sTREM-1) has proven to be a good biomarker for sepsis. For the diagnosis ventilator-associated pneumonia (VAP), however, there have only been a few, relatively small, studies on the role of this receptor. The aim of the study was to evaluate the usefulness of sTREM-1 in bronchoalveolar lavage fluid (BALF) from Intensive Care Unit patients as rapid diagnostic test for VAP. Methods  The concentration of sTREM-1 in 240 BALF samples was measured using a quantitative sandwich enzyme immunoassay. Two researchers who were blind to the assay results determined whether a VAP was present or not. Clinical suspicion of a VAP was confirmed by the presence of ≥2% cells containing intracellular organisms and/or a quantitative culture result of ≥10⁴ colony forming units per millilitre BALF. Results  The mean concentration of sTREM-1 was significantly higher in the BALF of patients with confirmed VAP than in that of patients without confirmed VAP. However, the area under the receiver-operating characteristic curve was 0.58 (95% confidence interval 0.50–0.65, P = 0.04). Conclusions  The results imply that the sTREM-1 assay in BALF may not be discriminative for VAP.     

Bacterial ventilator-associated pneumonia: bronchoalveolar lavage results are not influenced by dilution

Objective

This study was designed to determine if bronchoalveolar lavage (BAL) quantitative culture results can be used confidently for the diagnosis of bacterial ventilator-associated pneumonia (VAP) without taking dilution into account.

Design

Prospective observational cohort study.

Setting

A 12-bed medical ICU in a teaching hospital.

Patients

A total of 241 BAL (three 50-mL aliquots) were performed in 127 patients presenting a suspicion of VAP.

Interventions

All consecutive adults who were ventilated more than 48 h were included if VAP was clinically suspected. A dilution factor, k, was developed according to the formula: dilution factor k = concentration of urea in plasma/concentration of urea in lavage fluid recovered. Using this dilution factor, the quantitative bacterial counts were interpreted accordingly with a corrected positive threshold at 10⁵ colony forming unit (CFU) mL^?1.

Measurements and results

Eighty-nine BAL with at least one micro-organism ≥10⁴ CFU mL^?1 were identified (37%). In 176 BAL (73%), k ranged from 10 to 100. Median k was 24.4 (9.7–40.2) in VAP group and 24.6 (13.1–57.8) in patients without pneumonia (NS). Among the 25 BAL with micro-organism counts of 10⁴ CFU mL^?1, 3 had a dilution factor lower than 10, resulting in corrected counts below the threshold of 10⁵ CFU mL^?1. Two out of 15 patients with micro-organism counts of 10³ CFU mL^?1 had corrected micro-organism counts of 10⁵ CFU mL^?1. Finally, only five BAL (2.1%) were misclassified when the dilution correction factor was applied.

Conclusions

Using urea as dilution factor, we showed that BAL dilution variations did not alter the interpretation of BAL quantitative bacterial culture when administrating three aliquots of 50 mL of saline.

     

Bronchoalveolar lavage in diagnosis of ventilator-associated pneumonia in patients with burns

Ventilator-associated pneumonia (VAP) remains a major cause of morbidity and mortality for patients with burns. In nonburn populations, bronchoalveolar lavage (BAL) excludes other pathology such as systemic inflammatory response syndrome. We hypothesized that BAL would decrease our false-positive VAP rate. All ventilated patients with burn injury who were admitted to our institution from July 2000 through June 2003 were included. After June 2001, BAL was used to make the diagnosis of VAP, with > or =10(4) organisms considered a positive result. Fifty patients met criteria for VAP, 21 in the pre-BAL period and 29 in the BAL period. Six patients (21%) in the BAL group had quantitative cultures <10(4) and were not treated. The outcomes for these patients were not different than those treated for VAP. There were no differences in age, TBSA size, antibiotic use, or ventilator days for the pre-BAL or BAL groups, although the pneumonia rate was lower for the BAL time period. The use of BAL eliminated the unnecessary antibiotic treatment of 21% of patients in the BAL time period and was associated with a lower rate of VAP.     

Clinical impact of pulmonary sampling site in the diagnosis of ventilator-associated pneumonia: A prospective study using bronchoscopic bronchoalveolar lavage

PurposeIt is unclear whether ventilator-associated pneumonia (VAP) is actually a bilateral and multifocal process. In addition, the diagnostic role of chest x-ray is under debate. Assuming a low microbiologic concordance between the left and right lungs, the reliability of a single pulmonary sampling becomes questionable. The purpose of this study was to determine whether the choice of the pulmonary sampling area is clinically relevant in the management of VAP.MethodsIn 79 patients admitted to a university general intensive care unit with clinically suspected VAP, right- and left-lung bronchoalveolar lavage (BAL) samples were taken with separate bronchoscopes and quantitatively cultured. Primary end-point variable was microbiologic concordance rate between right- and left-lung BAL cultures. Secondary outcomes included predictors of microbiologic concordance, rates of appropriate antibiotic treatment, and diagnostic accuracy of chest x-ray.ResultsBAL cultures were bilaterally negative in 21 (27%) of 79 patients, bilaterally positive in 36 (46%), and unilaterally positive (right in 12, left in 10) in 22 (28%). Intra-patient concordance was observed in 47 (59.5%) of 79 cases and independently associated with purulent secretions and bilateral infiltrates on chest x-ray. In simulated prescribing experiments, treatments chosen based on right or left cultures alone were as appropriate as those based on bilateral data in > 90% of cases. The presence of a radiographic infiltrate in the sampling area predicted BAL culture positivity with a positive predictive value of only 61%.ConclusionsIn patients with clinically suspected VAP (especially those without purulent secretions or without radiographically documented bilateral infiltrates), quantitative culture of a single BAL sample may provide an incomplete assessment of lung microbiology, without having a relevant impact on the appropriateness of antimicrobial treatment. These findings suggest that single sampling of respiratory secretions, regardless radiographic opacity, seems to be a reliable diagnostic method in the management of VAP.     

Ventilator-associated pneumonia and atelectasis: evaluation through bronchoalveolar lavage fluid analysis

OBJECTIVE: Surfactant offers protection against alveolar collapse and contributes to the local defense mechanism, but it is unclear if surfactant alterations have a role in the development of atelectasis or ventilator-associated pneumonia (VAP). The present study was undertaken to monitor surfactant, as well as biochemical BAL fluid alterations, during the course of VAP and atelectasis in mechanically ventilated patients without primary cardiopulmonary disease, to elucidate the pathogenesis and to differentiate these two entities. DESIGN. Prospective controlled study. SETTING: 14-bed general ICU of a 750-bed University Hospital. PATIENTS: Sixty-one ventilated patients, without primary cardiopulmonary disease-normal initial chest X-ray, satisfactory oxygenation (PaO(2)/FiO(2)>300 mmHg), and expected time of ventilation exceeding 2 weeks-were initially enrolled. Twelve of them developed VAP and eight lobar or segmental atelectasis during the 2-week study period. INTERVENTIONS: An initial BAL was performed in all patients within 48 h from admission. Patients who developed VAP or atelectasis were subjected to a second and third BAL during and after the resolution of VAP or atelectasis, respectively. MEASUREMENTS AND RESULTS: VAP and atelectasis resulted in a significant increase of total protein and markers of inflammation, such as PAF and neutrophils, which partially remitted after their resolution. Large surfactant aggregates, which contribute to surface tension decrease, were significantly reduced during both entities and remained low even after their resolution. CONCLUSIONS: BAL alterations during VAP and atelectasis suggest increased alveolar-capillary permeability, severe surfactant abnormalities, and signs of local inflammatory reaction. These alterations are associated with the observed deteriorated gas exchange and lung mechanics and could predispose to further lung injury in ventilated patients.