BACKGROUND:The study aims to investigate an optimal indicator for changing the filter during the continuous renal replacement therapy(CRRT)in intensive care unit(ICU)patients with acute kidney injury(AKI).METHODS:Pati...BACKGROUND:The study aims to investigate an optimal indicator for changing the filter during the continuous renal replacement therapy(CRRT)in intensive care unit(ICU)patients with acute kidney injury(AKI).METHODS:Patients with AKI requiring CRRT in an ICU were randomly divided into two groups for crossover trial,i.e.,groups A and B.Patients in the group A were firstly treated with continuous veno-venous hemofiltration(CVVH),followed by continuous veno-venous hemodiafiltration(CVVHDF).Patients in the group B were firstly treated with CVVHDF followed by CVVH.Delivered doses of solutes with different molecular weights at the indicated time points between groups were compared.A correlation analysis between the delivered dose and pre-filter pressure(P_(PRE))and transmembrane pressure(P_(TM))was performed.Receiver operating characteristic(ROC)curves were constructed to evaluate the accuracy of P_(TM) as an indicator for filter replacement.RESULTS:A total of 50 cases were analyzed,27 in the group A and 23 in the group B.Delivered doses of different molecular-weight solutes significantly decreased before changing the filter in both modalities,compared with those at the initiation of treatment(all P<0.05).In the late stage of CRRT,the possible rebound of serum medium-molecular-weight solute concentration was observed.P_(TM) was negatively correlated with the delivered dose of medium-molecular-weight solute in both modalities.The threshold for predicting the rebound of serum concentration of medium-molecularweight solute by P_(TM) was 146.5 mm Hg(1 mm Hg=0.133 k Pa).CONCLUSIONS:The filter can be used as long as possible within the manufacturer’s safe use time limits to remove small-molecular-weight solutes.P_(TM) of 146.5 mm Hg may be an optimal indicator for changing the filter in CRRT therapies to remove medium-molecular-weight solutes.展开更多
利用1901—2010年帕默尔指数(PDSI)和1981—2010年CMAP降水、NCAR 700 h Pa位势高度等格点资料,分析亚非干旱、半干旱带中北非、中东、中亚西部、中亚东部至中国西北地区西部及中国西北地区东部、华北和东北等7个区域PDSI的时空演变特...利用1901—2010年帕默尔指数(PDSI)和1981—2010年CMAP降水、NCAR 700 h Pa位势高度等格点资料,分析亚非干旱、半干旱带中北非、中东、中亚西部、中亚东部至中国西北地区西部及中国西北地区东部、华北和东北等7个区域PDSI的时空演变特征。结果表明:北非至中东地区大部,前20 a(1901—1920年)PDSI为-1~2,干旱较轻或相对不旱;1920年代以后PDSI为-4^-2,干旱较重。与其他地区不同的是,中亚东部至中国西北地区西部1980年代以后PDSI>0,这与该区同时期700 h Pa位势高度下降及夏季降水量增加有关。PDSI≤-2的干旱期,有从北非地区到中国东北地区逐区向东扩展的趋势,后延推移间隔约为24~31 a,这对干旱气候预测有一定的参考意义。展开更多
基金supported by Kunshan Science and Technology Special Fund(Social Development Category,KS18040)。
文摘BACKGROUND:The study aims to investigate an optimal indicator for changing the filter during the continuous renal replacement therapy(CRRT)in intensive care unit(ICU)patients with acute kidney injury(AKI).METHODS:Patients with AKI requiring CRRT in an ICU were randomly divided into two groups for crossover trial,i.e.,groups A and B.Patients in the group A were firstly treated with continuous veno-venous hemofiltration(CVVH),followed by continuous veno-venous hemodiafiltration(CVVHDF).Patients in the group B were firstly treated with CVVHDF followed by CVVH.Delivered doses of solutes with different molecular weights at the indicated time points between groups were compared.A correlation analysis between the delivered dose and pre-filter pressure(P_(PRE))and transmembrane pressure(P_(TM))was performed.Receiver operating characteristic(ROC)curves were constructed to evaluate the accuracy of P_(TM) as an indicator for filter replacement.RESULTS:A total of 50 cases were analyzed,27 in the group A and 23 in the group B.Delivered doses of different molecular-weight solutes significantly decreased before changing the filter in both modalities,compared with those at the initiation of treatment(all P<0.05).In the late stage of CRRT,the possible rebound of serum medium-molecular-weight solute concentration was observed.P_(TM) was negatively correlated with the delivered dose of medium-molecular-weight solute in both modalities.The threshold for predicting the rebound of serum concentration of medium-molecularweight solute by P_(TM) was 146.5 mm Hg(1 mm Hg=0.133 k Pa).CONCLUSIONS:The filter can be used as long as possible within the manufacturer’s safe use time limits to remove small-molecular-weight solutes.P_(TM) of 146.5 mm Hg may be an optimal indicator for changing the filter in CRRT therapies to remove medium-molecular-weight solutes.
文摘利用1901—2010年帕默尔指数(PDSI)和1981—2010年CMAP降水、NCAR 700 h Pa位势高度等格点资料,分析亚非干旱、半干旱带中北非、中东、中亚西部、中亚东部至中国西北地区西部及中国西北地区东部、华北和东北等7个区域PDSI的时空演变特征。结果表明:北非至中东地区大部,前20 a(1901—1920年)PDSI为-1~2,干旱较轻或相对不旱;1920年代以后PDSI为-4^-2,干旱较重。与其他地区不同的是,中亚东部至中国西北地区西部1980年代以后PDSI>0,这与该区同时期700 h Pa位势高度下降及夏季降水量增加有关。PDSI≤-2的干旱期,有从北非地区到中国东北地区逐区向东扩展的趋势,后延推移间隔约为24~31 a,这对干旱气候预测有一定的参考意义。
