Hepatocyte growth factor protects pulmonary endothelial barrier against oxidative stress and mitochondria-dependent apoptosis / 中华医学杂志(英文版)

BACKGROUND@#Pulmonary microvascular endothelial cells (PMVECs) were not complex, and the endothelial barrier was destroyed in the pathogenesis progress of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Previous studies have demonstrated that hepatocyte growth factor (HGF), which was secreted by bone marrow mesenchymal stem cells, could decrease endothelial apoptosis. We investigated whether mTOR/STAT3 signaling acted in HGF protective effects against oxidative stress and mitochondria-dependent apoptosis in lipopolysaccharide (LPS)-induced endothelial barrier dysfunction and ALI mice.@*METHODS@#In our current study, we introduced LPS-induced PMEVCs with HGF treatment. To investigate the effects of mammalian target of rapamycin (mTOR)/signal transducer and activator of transcription 3 (STAT3) pathway in endothelial oxidative stress and mitochondria-dependent apoptosis, mTOR inhibitor rapamycin and STAT3 inhibitor S3I-201 were, respectively, used to inhibit mTOR/STAT3 signaling. Moreover, lentivirus vector-mediated mTORC1 (Raptor) and mTORC2 (Rictor) gene knockdown modifications were introduced to evaluate mTORC1 and mTORC1 pathways. Calcium measurement, reactive oxygen species (ROS) production, mitochondrial membrane potential and protein, cell proliferation, apoptosis, and endothelial junction protein were detected to evaluate HGF effects. Moreover, we used the ALI mouse model to observe the mitochondria pathological changes with an electron microscope in vivo.@*RESULTS@#Our study demonstrated that HGF protected the endothelium via the suppression of ROS production and intracellular calcium uptake, which lead to increased mitochondrial membrane potential (JC-1 and mitochondria tracker green detection) and specific proteins (complex I), raised anti-apoptosis Messenger Ribonucleic Acid level (B-cell lymphoma 2 and Bcl-xL), and increased endothelial junction proteins (VE-cadherin and occludin). Reversely, mTOR inhibitor rapamycin and STAT3 inhibitor S3I-201 could raise oxidative stress and mitochondria-dependent apoptosis even with HGF treatment in LPS-induced endothelial cells. Similarly, mTORC1 as well as mTORC2 have the same protective effects in mitochondria damage and apoptosis. In in vivo experiments of ALI mouse, HGF also increased mitochondria structural integrity via the mTOR/STAT3 pathway.@*CONCLUSION@#In all, these reveal that mTOR/STAT3 signaling mediates the HGF suppression effects to oxidative level, mitochondria-dependent apoptosis, and endothelial junction protein in ARDS, contributing to the pulmonary endothelial survival and barrier integrity.

Research progress of weaning from mechanical ventilation guided by electrical impedance tomography / 中华危重病急救医学

Weaning?failure?from?mechanical?ventilation?is?an?important?clinical?problem,?the?traditional?methods?of?assessing?whether?patients?can?be?weaned?from?mechanical?ventilation?or?not?cannot?meet?the?clinical?needs.?Finding?more?effective?weaning?indicators?to?determine?the?optimal?timing?of?weaning?has?important?clinical?value?for?improving?the?outcome?of?weaning?and?reducing?the?mortality?of?patients.?As?a?new?method?of?assessing?respiratory?function?of?patients,?electrical?impedance?tomography?(EIT)?is?gradually?applied?to?the?clinic,?and?its?guided?assessment?of?respiratory?function?may?open?a?new?way?for?directing?successful?weaning.?This?article?reviews?the?progress?of?EIT?in?ventilation?weaning,?in?order?to?provide?a?new?judgment?method?and?theoretical?basis?for?the?successful?weaning.

Effects of sedation with propofol or dexmedetomidine on volume responsiveness in critically ill patients with acute circulatory failure / 中华麻醉学杂志

Objective To evaluate the effects of sedation with propofol or dexmedetomidine on volume responsiveness in critically ill patients with acute circulatory failure. Methods Ninety?one critically ill patients with acute circulatory failure, aged 20-90 yr, weighing 40-80 kg, requiring sedation with propofol or dexmedetomidine, of Acute Physiology and Chronic Health Evaluation Ⅱ scores 12-47, of Sequential Organ Failure Assessment scores 1-18, and of NYHA Ⅰ or Ⅱ, were included. The patients were randomly divided into 2 groups using a random number table: propofol group ( n = 45 ) and dexmedetomidine group ( n=46) . Before and after propofol or dexmedetomidine sedation, when Richmond Agitation Sedation Scale score reached -2 or -1 ( BIS value 60-75) ( after sedation) , passive leg?raising (PLR) test was performed to evaluate volume responsiveness. An increase in cardiac index (ΔCI) ≥10% after PLR was considered to be a positive response, whereas ΔCI<10% after PLR was considered to be a negative response. The patients who presented with negative responses before sedation served as negative volume responsiveness subgroups ( N subgroups ) , that was PN subgroup and DN subgroup. Results The positive rates of volume responsiveness were 64% ( 14 cases) and 25% ( 5 cases) in PN and DN subgroups, respectively. The positive rates of volume responsiveness were significantly higher after sedation than before sedation in PN and DN subgroups. Compared with DN subgroup, the positive rates of volume responsiveness were significantly increased after sedation in PN subgroup. Conclusion For the critically ill patients with acute circulatory failure, both propofol and dexmedetomidine sedation can improve volume responsiveness, and propofol provides better efficacy than dexmedetomidine.

Effects of high-frequency oscillatory ventilation and conventional mechanical ventilation on oxygen metabolism and tissue perfusion in sheep models of acute respiratory distress syndrome / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>High-frequency oscillatory ventilation (HFOV) allows for small tidal volumes at mean airway pressures (mPaw) above that of conventional mechanical ventilation (CMV), but the effect of HFOV on hemodynamics, oxygen metabolism, and tissue perfusion in acute respiratory distress syndrome (ARDS) remains unclear. We investigated the effects of HFOV and CMV in sheep models with ARDS.</p><p><b>METHODS</b>After inducing ARDS by repeated lavage, twelve adult sheep were randomly divided into a HFOV or CMV group. After stabilization, standard lung recruitments (40 cmH2O × 40 seconds) were performed. The optimal mPaw or positive end-expiratory pressure was obtained by lung recruitment and decremental positive end-expiratory pressure titration. The animals were then ventilated for 4 hours. The hemodynamics, tissue perfusion (superior mesenteric artery blood flow, pHi, and Pg-aCO2), oxygen metabolism and respiratory mechanics were examined at baseline before saline lavage, in the ARDS model, after model stabilization, and during hourly mechanical ventilation for up to 4 hours. A two-way repeated measures analysis of variance was applied to evaluate differences between the groups.</p><p><b>RESULTS</b>The titrated mPaw was higher and the tidal volumes lower in the HFOV group than the positive end-expiratory pressure in the CMV group. There was no significant difference in hemodynamic parameters between the HFOV and CMV groups. There was no difference in the mean alveolar pressure between the two groups. After lung recruitment, both groups showed an improvement in the oxygenation, oxygen delivery, and DO2. Lactate levels increased in both groups after inducing the ARDS model. Compared with the CMV group, the superior mesenteric artery blood flow and pHi were significantly higher in the HFOV group, but the Pg-aCO2 decreased in the HFOV group.</p><p><b>CONCLUSION</b>Compared with CMV, HFOV with optimal mPaw has no significant side effect on hemodynamics or oxygen metabolism, and increases gastric tissue blood perfusion.</p>

The effect of stress dose glucocorticoid on patients with acute respiratory distress syndrome combined with critical illness-related corticosteroid insufficiency / 中华内科杂志

Objective To investigate the effect of stress dose glucocorticoid on patients with acute respiratory distress syndrome (ARDS) combined with critical illness-related corticosteroid insufficiency (CIRCI).Methods All early ARDS patients combined with CIRCI were screened by an adrenal corticotrophic hormone (ACTH) test and randomly divided into treatment group (hydrocortisone 100 mg intravenous,3 times/day,consecutively for 7 days,n =12 ) and control group (equivalent normal saline,n =14 ).General clinical data,changes of arterial blood gas,hemodynamics and respiratory mechanics were observed and recorded at admission and at 7 days after treatment.Ventilator-free and shock-free days,ICU stay within 28 days after admission were recorded and 28-day mortality was used as judge prognosis index.Results CIRCI rate in 45 early ARDS patients was 57.8％ ( 26 patients),and the shock rate was markedly higher in ARDS patients with CIRCI than patients without CIRCI (46.2％ vs 5/19 ).There were no significant differences in baseline parameters,oxygenation and illness severity between the treatment and control groups,except for markedly lower lactic level in the treatment group [ 2.7 ( 1.2,3.9 ) mmol/L vs 4.6 ( 2.5,6.3 ) mmol/L,P ＜ O.05].After 7 days of treatment,PaO2/FiO2 markedly increased,while heart rate obviously decreased in the both groups.Compared with the control group,survival time of patients was significantly longer and shock rate of the patients was markedly lower in treatment group within 28 days (5/12 vs 10/14,P ＜ 0.05).The 28-day mortality,which were adjusted by baseline arterial lactic,was lower in the treatment group (2.6/12 ) than in the control group (5.8/14) while with no significant difference ( P ＞ 0.05 ).There was no significant difference in complication incidence between the two groups.Conclusion Stress dose glucocorticoid could reduce shock incidence and prolong survival time,and has a tendency of lower 28-day mortality in early ARDS patients combined with CIRCI.

The evaluation value of severity and prognosis of septic shock patients based on the arterial-to-venous carbon dioxide difference / 中华内科杂志

Objective To assess the value of central venous-to-arterial carbon dioxide difference [ P( cv-a) CO2 ] in evaluation of disease severity and prognosis in patients with septic shock.Methods There were 45 consecutive resuscitated septic shock patients from April 2009 to October 2010 included immediately after their admission into our ICU.The patients were divided into low P(cv-a) CO2 group and high P(cv-a) CO2 group according to a threshold of 6 mm Hg ( 1 mm Hg=0.133 kPa).All patients were treated by early goal directed therapy (EGDT).The parameters of hemodynamics,lactate clearance rate,the Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ ) score,the sequential organ failure assessment (SOFA)score,6 h rate of EGDT achievement,the ICU mortality and 28 days in-hospital mortality were recorded for all patients.Results There were 30 patients in the low P(cv-a) CO2 group,and 15 in the high P(cv-a)CO2group.There were no significant differences between low P(cv-a) CO2 and high P(cv-a) CO2 patients in age,APACHE Ⅱ score and SOFA score (all P ＞ 0.05 ).Compared with the high P(cv-a)CO2 group,the low P(cv-a) CO2 group had higher cardiac index ( CI ) and 24 h CI,higher delivery O2 ( DO2 ) and 24 h DO2,higher central venous oxygen saturation ( ScvO2 ) [ (74 ± 9) ％ vs (67 ± 8) ％ ],lower lactate [ ( 3.4 ± 2.1 )mmol/L vs (5.7 ± 4.5 ) mmol/L] and higher △SOFA score [ (0.7 ± 1.8 ) vs ( - 0.4 ± 1.1 ) ],lower 24 h SOFA score [ (7.8 ± 2.0) vs (9.8 ± 2.0 ) ],higher 6 h rate of EGDT achievement ( 83.3％ vs 53.3 ％ )(P ＜ 0.05 ),however,there were no differences in 28 days mortality and ICU mortality between the two groups ( P ＞ 0.05 ).Conclusion P(cv-a) CO2 might be an indicator for predicting the severity of patients with septic shock and evaluating tissue perfusion.

Subglottic secretion drainage for preventing ventilator-associated pneumonia: a Meta-analysis / 中华急诊医学杂志

ObjectiveTo assess the efficacy of subglottic secretion drainage for preventing ventilatorassociated pneumonia.MethodsData of relevant randomized controlled trials (RCT) from January 1991 to June 2010 were collected,and data were split into two groups,namely draining group and non-draining group.Meta analysis of ventilator-associated pneumonia was carried out for finding the incidence and mortality in patients with mechanical ventilation using the methods recommended by the Cochrane Collaboration.ResultsSeven RCTs met the inclusion criteria and 1647 patients were enrolled.Subglottic secretion drainage reduced the incidence of ventilator-associated pneumonia ( OR =0.45,95％ confidence interval [CI]:0.32 - 0.63 ),primarily by reducing early-onset pneumonia.But the mortalities of ventilator associated pneumonia were not significantly different between the two groups ( OR =1.03,95％ confi dence interval [CI]:0.75 - 1.41 ).ConclusionsSubglottic secretion drainage appeared effective in preventing ventilator associated pneumonia among patients expected to require ＞48 hours of mechanical ventilation,but the mortality was unchanged.

Prognostic value of the pulmonary dead-space fraction in patients during the early phases of acute respiratory distress syndrome / 中华急诊医学杂志

ObjectiveTo evaluate the association between alveolar dead space fraction and the prognosis of patients with acute respiratory syndrome in the early phase ( ＜ 3 days).MethodsTwentythree patients with ARDS were enrolled in this study.The VD/VT was measured by the single breath test of CO2 (SBT-CO2).The age,heart rate,mean arterial pressure,APACHE Ⅱ,Murray lung injury score,functional residual capacity ( FRC ),PaO2/FiO2,tidal volume,airway plateau pressure ( Pplat ),static pulmonary compliance (Cst),28-day mortality were recorded.ResultsThe alveolar dead-space fraction was markedly elevated (0.59 ±0.06) and the mean FRC was markedly decreased (1643 ±409) ml in the early phase of ARDS.The mortality of 28 days was 52.2％.The mean dead-space fraction was significantly higher in non-survived patients than that in survival [(0.64 ± 0.08 ) vs.(0.53 ±0.04 )].VD/VT was correlated significantly with Murray lung injury score ( r=0.464,P =0.026).The area under the ROC curve for dead space fraction was 0.867,with sensitivity of 83％,and specificity of 82％.Conclusions Increased alveolar dead-space fraction of patients in the early phases of ARDS is associated with greater risk of death.

Effects of ventilator circuit change frequency on ventilator-associated pneumonia: Meta-analysis / 中华急诊医学杂志

ObjectiveTo evaluate the effects of ventilator circuit change frequency on ventilatorassociated pneumonia (VAP).MethodsMeta-analysis of effects of ventilator circuit change frequency on VAP was conducted with study-level data from 1995 to 2010 in Pubmed,Embase,Web of Science databases.ResultsNine articles were included (sample size:20 326 mechanically ventilated patients).Analysis of six articles showed that the incidence of VAP in ventilator circuit change every 2 or 3 days was 4.05％,while 3.65％ in ventilator circuit change every 7 days.Compared with change ventilator circuit every 2 or 3 days,the risk ratio (RR) of VAP in weekly changes was 0.77 [0.54,1.09] ( P =0.14 ).Analysis three articles showed that compared to ventilator circuit change every 7 days with 15.89％ incidence of VAP,the incidence of VAP in circuit change more than 14 days was 14.9％,and RR was 0.98 [0.69,1.39](P =0.91 ).ConclusionsRegular ventilator circuit change frequency in various intervals can't difference in the incidence of VAP in mechanical ventilation patients.

Value of using angled insonation technique in three dimensional ultrasonic imaging of the fetal palate / 中华超声影像学杂志

Objective To evaluate the value of angled insonation technique in obtaining the volumes of the fetal palate and in three-dimensional post-processing.Methods Five hundred and sixty-six cases of 20~28 weeks fetuses with normal face were confirmed by systemic ultrasound examinations and post-natal examination.The volumes in the standard midsagittal plane and angled midsagittal plane were obtained,then post-processed these data by 4D-View software.The same technology was used for volume data acquisition and processing to 1 case of cleft lip and palate fetal.Results In 566 fetuses,two groups of volume data were successfully acquired in 458 cases (standard midsagittal plane group) and 411 cases (angled midsagittal plane group).Fetal primary palate in the standard group and the angled group can be both well visualized(100%).Axial plane of hard palate can not be reconstructed in the standard group.Only 36% of the fetal hard palate's coronal plane and transoral oblique coronal plane can be reconstructed.The visualization rate of soft palate was 87% in the standard group,which was slightly higher than the angled group (82%).The visualization rate of hard palate's axial plane,coronal plane and transoral oblique coronal plane was 100% respectively in the angled group.Cleft alveolar process involving the secondary palate can be clearly visualized in 1 case of cleft lip and palate fetus.Conclusions By using the angled insonation technique,which is based on clearly visualizing secondary palate to obtain volumes,using three-dimensional post-processing technique can obtain the conventional three orthogonal planes and any other section of the whole palate.By using it we can assess the integrity of fetal palate,diagnose cleft lip with or without cleft palate and classify the cleft palate,even make prenatal diagnosis of the isolated cleft palate possible.

Effects of respiratory system elasticity resistance on oxygenation after recruitment maneuvers of ALI patients: a meta-analysis / 中华急诊医学杂志

Objective To investigate the effects of elasticity resistance (Ers) in respiratory system on oxygenation in patients with acute lung injury (ALI) after recruitment maneuvers (RM). Method Meta-analysis of data about the effects of recruitment maneuvers on oxygenation in ALI patients with different elasticity resistances in respiratory system carried out with pooling of study-oriented data stored in Pubmed, Embase, Web of Science databases from January 1999 to June 2010. Results A total of 281 articles were taken, and 20 of them included a sample size of 395 ALI patients. In patients treated with RM in different degrees of respiratory system elasticity resistance ( ≥33.3 cmH2O/L and ＜33.3 cmH2O/L), the effect of RM was better in patients with the high respiratory system elasticity resistance than that with the low one [(51.97 + 8.89) mmHg vs. (35.13 ± 10.33 ) mmHg], P ＜ 0. 01 ), but the high respiratory system elasticity resistance was potentially to lower blood pressure [(4. 33 ± 1.32 ) mmHg vs. (0.22 ± 1.03 ) mmHg],P ＜ 0.01 ). Conclusions This study suggests RM could improve oxygenation of ALI patients with high respiratory system elasticity resistance, and caution must be made to avoid hypotension during RM.

Use of extracorporeal membrane oxygenation on adults with adult acute respiratory distress syndrome: a meta-analysis and systematic review / 中华急诊医学杂志

Objective To investigate the effects of extracorporeal membrane oxygenation (ECMO) on survival of adult from acute respiratory distress syndrome (ARDS). Method We searched Pubmed, Embase, Cochrane Library, Web of Science databases to find relevant literatues on ECMO in treatment of ARDS, which are reported from January 1966 to June 2010. Meta analyses was performed. Results Three papers about randomized controlled trial (RCT) of evaluating ECMO in patients with severe ARDS were enrolled for analyses. Meta-analysis of the three randomized controlled trials revealed ECMO did not decrease the mortality of ARDS patients. However, the cumulative meta-analysis of randomized trials showed ECMO had a protective effect on patients with ARDS. The most recent observational studies suggested that ECMO significantly decreased the mortality of ARDS caused by H1 N1 viral pneumonia. Conclusions There is no evidence to prove the benefit of ECMO in patients with ARDS. However, ECMO should be considered to use in early stage of ARDS as a last rescue resort for potentially reversible severe acute respiratory failure. Further investigation of large sample of high quality RCTs is needed.

Effects of noninvasive positive pressure ventilation on mortality and rate of reintubation in mechanical ventilation patients after extubation: a meta-analysis / 中华急诊医学杂志

Objective To evaluate the effects of noninvasive positive pressure ventilation (NPPV)used after extubation on mortality and rate of reintubation in patients with acute respiratory failure (ARF).Method Pubmed, Embase, Web of Science databases were searched to collect data from randomized controlled trials (RCT) of the relevant subject from January 1995 to May 2010. Meta analysis of data about NPPV on mortality and rate of reintubation in patients after extubation carried out by using the methods recommended by the Cochrane Collaboration. Results Six RCTs included sample size of 381 NPPV and 379routine medical care. In total, the mortalities of patients in NPPV group and routine medical care group were 18.6% (62/334) vs. 21.6% (72/333), respectively, and the rates of reintubation of the two groups were 30.2% (115/381) vs. 33.5% (127/379), respectively. Compared with routine medical care, NPPV did not significantly reduce the mortality ( OR: 0.83, 95% CI =0.57 ～ 1.21 ,P =0.34) and rate of reintuation( OR: 0.83, 95% CI = 0.59 ～ 1.16, ( P = 0.27). When the analysis was focused to the four studies of them in which patients received NPPV as soon as extubation, the results were quite different. From these four studies, the mortalities of patients in NPPV group and routine medical care group were 12. 2% (22/181) vs.23.9% (44/184),(P=0.004), and the rate of reintubation of the two groups were 14.0% (32/228) vs.20.4% (47/230), (P =0.07). Compared with routine medical care, early application of NPPV to patients after extubation reduced the mortality. Conclusions This study suggests the favorable effects of early application of NPPV to patients after extubation on the mortality of acute respiratory failure.

A meta-analysis of the effects of direct hemoperfusion with polymyxin B-immobilized fiber on prognosis in severe sepsis / 中华内科杂志

Objective To investigate the effects of direct hemoperfusion with polymixin B-immobilized fiber (DHP-PMX) in patients with sepsis. Methods We searched Pubmed, Embase, Web of Science databases and identified relevant randomized controlled trials (RCT) from January 1995 to May 2010. Meta-analysis of DHP-PMX on mortality and levels of endotoxin in patients with sepsis were conducted using the methods recommended by the Cochrane Collaboration. Results Eleven RCTs were included.Eight of them included the mortality of patients (sample size: 211 DHP-PMX and 178 conventional medical therapy). In total, the mortalities of patients with sepsis in DHP-PMX group and conventional group were 37.4% (79/211) and 68.5% (122/178) respectively. Compared with the conventional medical therapy,DHP-PMX appeared to significantly reduce mortality ( OR =0.24,95% CI 0.16-0.38 ,P ＜0.000 01 ). The results were similar when two RCTs enrolling patients with methicillin resistant staphylococcus aureus (MRSA) infections were excluded( OR =0. 27,95% CI 0. 17-0. 45, P ＜0. 000 01 ). When the analysis was limited to the nine studies that reported 28- to 30-day mortality, results were unchanged( OR =0. 29,95% CI 0.17-0.48 ,P ＜0.000 01 ). Six RCTs had the available data of endotoxin. The level of endotoxin decreased 31 ng/L(95% CI 22.46-39.55 ) after DHP-PMX therapy, and the decreasing was statistically significant (P＜0. 000 01 ) ,while the level of endotoxin in patients of conventional group did not change (P =0.94).Conclusions This study suggests a favorable effects of DHP-PMX on mortality and endotoxin decreasing in patients with sepsis. However, lack of enough cases and blinding need to be considered. Further investigation with large sample of high quality RCTs is needed.

Dead space guided positive end-expiratory pressure in patients with acute respiratory distress syndrome / 中华内科杂志

ObjectiveTo evaluate the value of dead space fraction (VD/VT) guided positive end expiratory pressure ( PEEP ) in acute respiratory distress syndrome ( ARDS ).Methods Twenty-three intubated and mechanically ventilated patients with early ARDS were enrolled in the study.PEEP was titrated by lowest VD/VT.Parameters of oxygenation and respiratory mechanics were observed.Results PEEP titrated by lowest VD/VT and highest static lung compliance ( CLst ) ( P ＞ 0.05 ) respectively,were lower than PEEP titrated by optimal oxygenation ( P ＜ 0.05),but there was no significant difference between lowest VD/VT and highest Ctst method.The VD/VT that ventilated on PEEP titrated by the lowest VD/VT decreased than its basal level.There was no difference significantly between the VD/VT that ventilated on PEEP elected by the other two methods with basal level ( P ＞ 0.05 ).The the ratio of arterial PO2 to the inspired oxygen fraction (PaO2/FiO2)ratios improved significantly than the baseline values in three ventilation strategies,and that ventilated on PEEP targeting the lowest VD/VT was lower than PEEP targeting optimal oxygenation.The plateau airway pressure that ventilated on PEEP targeting optimal oxygenation was higher than the other two methods.The functional residual capacity (FRC) of patients ventilated by PEEP targeting optimal oxygenation was increased than the lowest VD/VT and maximum CLst.Conclusions VD/VT could be one of the methods to titrate the optimal PEEP in patients with early ARDS.Optimal PEEP targeting the highest compliance in conjunction with the lowest dead space fraction indicated a maximumamount of effectively expanded alveoli.

Urinary neutrophil gelatinase-associated lipocalin and urinary interleukin-18 in early diagnosis of acute kidney injury in critically ill patients / 中华内科杂志

Objective To determine whether urinary neutrophil gelatinase-associated lipecalin (uNGAL) and urinary intedeukin-18 (uIL-18) are early markers of acute kidney injury (AKI) in critically ill patients. Methods Ninety-two critically ill patients were studied for one week after their enrollment into our hospital. During the study, 46 patients who met the RIFLE criteria were selected as AKI group and the remaining 46 patients without AKI taken as a control group. The two groups were matched for age, gender and illness severity. Urine samples were collected daily for one week. The receiver operating characteristic curve was used to evaluate the early diagnostic value of uNGAL, uIL-18 and serum creatininc (SCr). Results As compared with the levels obtained 3 days before the diagnosis of AKI, the uNGAL levels in the AKI group increased significantly (P <0. 05), while uIL-18 and SCr levels did not change 2 days prior to the diagnosis of A KI (all P > 0. 05). uNGAL and uIL-18 levels increased significantly (all P < 0. 05), while SCr levels did not change 1 day prior to the diagnosis of AKI in the AKI group (P > 0. 05). The levels of uNGAL, uIL-18 and SCr did not change significantly in the control group during the study period (all P > 0. 05). Three days before the diagnosis of AKI, concentrations of uNGAL, uIL-18 and SCr were not the predictive of AKI. Two days before the diagnosis of AKI, the area under the curve (AUC) of uNGAL was 0. 840 (95% CI 0. 672-1. 009, P < 0. 05), which indicated that uNGAL was the predictive of AKI while uIL-18 and SCr were not. One day before the diagnosis of AKI, the AUC of uNGAL and ulL-18 were 0. 830 (95 % CI 0. 711-0. 950, P < 0. 05) and 0. 818 (95 % CI 0. 697-0. 938, P < 0. 05), indicating that uNGAL and uIL-18 were the predictive of AKI while SCr was not. Conclusion uNGAL and uIL-18 may be the early predictive markers of AKI in critically ill patients.