Objective Acute renal failure (ARF) requiring renal replacement therapy (RRT) was reported in 0.33％to 9.5％ patients after cardiac surgery.This study was designed to assess the clinical usefulness and accuracy of 3 clinical tools for the prediction of ARF after cardiac surgery in Chinese patients.Methods Five hundred and four eligible patients with complete clinical data in our institution received prospective assessment for RRT and acute kidney injury (AKI) between June,2009 and November,2010.The clinical tools used were Cleveland ARF Score,acute kidney injury prediction following elective cardiac surgery(AKICS) and Simplified Renal Index(SRI).Hosmer—Lemeshow goodness-of-fit test was used to estimate the calibration.Discrimination was determined with receiver operating characteristic (ROC) curves and area under a ROC curve (AUC).Results Follow-up was completed in all 504 patients.The overall incidence of postoperative RRT was 3.17％(16/504) with a mortality of 37.5％,and the incidence of AKI was 5.36％ ( 27/504 ).Discrimination for the prediction of RRT and AKI was good for SRI measured with AUROCs:0.759 (95％ CI,0.643-0.874) for RRT and 0.773 (95％ CI,0.677-0.868 ) for AKI.SRI score performed better in terms of discrimination than Cleveland ARF score and AKICS in our study,which did not consist with results reported by other centers.Conclusion SRI scoring system is the most useful among three tools for predicting postoperative RRT and should be the first choice in Chinese patients for whom a cardiac surgery is planned.It can also be used in predicting the composite end point of AKI with an extended application in patients at risk for postoperative kidney dysfunction.

Objective To study the incidence of ventilator-associated pneumonia(VAP)and antimicrobial resistance of pathogens in an intensive care unit(ICU).Methods The occurrence of VAP in hospitalized patients with mechan-ical ventilation>48 hours between January 2011 and December 2012 were investigated,species and antimicrobial re-sistance of pathogens causing early onset-VAP (E-VAP,mechanical ventilation≤4 d)and late-onset VAP(L-VAP, mechanical ventilation>4 d)were compared.Results A total of 1 76 patients were investigated,incidence of VAP was 44.32% (78 cases);With the prolongation of mechical ventilation,incidence of VAP increased gradually (χ2=52.561,P<0.001).The incidence of L-VAP was significantly higher than E-VAP (58.33% [70/120]vs 14.29%[8/56])(χ2= 30.02,P<0.001).A total of 178 pathogens were isolated,gram-negative bacteria,gram-positive bac-teria and fungi were 104(58.43% ),46(25.84% ),and 28(15.73% )isolates respectively;97(54.49% )multidrug-resistance/pandrug resistance organisms (MDRO)were isolated. MDRO isolation rate in L-VAP patients was high-er than E-VAP patients([58.86% ,n= 93]vs [20.00% ,n= 4]),resistance rate of major pathogens causing L-VAP was significantly higher than E-VAP patients(allP<0.05).Fungi infection only occurred in L-VAP patients,the total antimicrobial resistance rate was 12.14% .Conclusion The prolongation of mechanical ventilation can increase the incidence of VAP,and resistance rate of pathogen in L-VAP is high.