Table 1. The fundamental characteristics and patient demographic data of included studies reporting data on early RRT versus late RRT.
| Auther, Year | Country | Study Design | Population | Early Mortality | Late Mortality | Severity ofIllness | Early RRT Criteria | Late RRT Criteria | Quality |
|---|---|---|---|---|---|---|---|---|---|
| Early time to RRT <12 h | |||||||||
| Bouman2002 | Netherlands | RCT | Multisystem | 20/70 | 9/36 | Early: SOFA 10.3;Late: SOFA 10.6 | Time to RRT<12 h | Time to RRT>12h | M |
| Piccinni2006 | Italy | Retrospective | Sepsis; ICU | 18/40 | 29/40 | Early: APACHE2=27.2;Late: APACHE2=27.8 | Time to RRT <12 h | No RRT | 7 |
| Andrade2007 | Brazil | Retrospective | Multisystem;Leptospirosis | 3/18 | 10/15 | Early: APACHE2=24.5;Late: APACHE2=26 | Mean time to RRT = 4.4hrs | Mean time to RRT = 27.3hrs | 5 |
| Wu VC2007 | China | Retrospective | Acute LiverFailure;Surgical ICU | 34/54 | 22/26 | Early: APACHE2=18;Late: APACHE2=19 | Mean time from ICU admit to RRT =4.4hrs; BUN<80 mg/dL ANDtraditional indications present | Mean time from ICU admit to RRT =11.1hrs; BUN>80 mg/dL ANDtraditional indications present | 6 |
| Manche2008 | Malta | Retrospective | Post CardiacSurgery | 14/56 | 13/15 | NR | Mean RRT start 8.6hrs post-op; Oliguria unresponsive to med mgmt | Mean RRT start 41.2hrs post-op; Oliguria refractory to med mgmt | 6 |
| Ji2011 | China | Retrospective | Post CardiacSurgery | 3/34 | 9/24 | Early: APACHE3= 69;Late: APACHE3= 88.2p<0.001 | Time from urine output <0.5ml/kg/h to RRT <12h; Mean oliguria to start of RRT 8.4hrs | Time from urine output <0.5ml/kg/h to RRT >12h; Mean oliguria to start of RRT21.5hrs | 6 |
| Shum2013 | China | Retrospective | Multisystem;Sepsis | 43/89 | 15/31 | Early: SOFA 13;Late: SOFA 12P=0.011 | Mean time from ICU admit to RRT= 10.8hrs (RIFLE criteria:‘Injury’ or ‘Failure’ criteria) | Mean time from ICU admit to RRT =20.7hrs (RIFLE criteria:‘pre- Risk’ or ‘Risk’ criteria) | 6 |
| Serpytis2014 | Lithuania | Retrospective | Multisystem;Sepsis | 30/42 | 39/43 | NR | Time from anuria to RRT <12hrs | Time from anuria to RRT >12hrs | 5 |
| Wald2015 | Canada | RCT | Multisystem | 16/48 | 19/52 | Early: SOFA 13.3;Late: SOFA 12.8 | Mean time to RRT = 9.7hrs | Meantime to RRT = 32hrs;Classic indications for RRT | H |
| Crescenzi2015 | Italy | Prospective | Post CardiacSurgery | 28/46 | 10/13 | NR | Time from urine output <0.5ml/kg/hto RRT <12h | Time from urine output <0.5ml/kg/h to RRT >12h | 6 |
| Zarbock2015 | Germany | RCT | Multisystem | 44/112 | 65/119 | Early: SOFA 15.6;Late: SOFA 16.0 | Time to RRT <8h; KDIGO stage 2 | Time to RRT <12h; Stage 3 AKIor no initiation | H |
| Gaudry2015 | France | RCT | Multisystem | 150/311 | 153/308 | Early: SOFA 10.9;Late: SOFA 10.8 | Time to RRT <6h; Stage 3 AKI | Classic indications for RRT; Oliguria or anuria >72hrs after randomization | H |
| Early time to RRT <24 h | |||||||||
| Elahi2004 | UK | Retrospective | Post Cardiacsurgery | 8/36 | 12/28 | NR | Mean RRT start 0.78 days;Low urine output <100ml within 8h after surgery | Mean RRT start 2.5 days; Traditional indications: Urea≥30mmol/L, Cr ≥250mmol/L, K >6.0mEq/L | 6 |
| Demirkilic2004 | Turkey | Retrospective | Post CardiacSurgery | 8/34 | 15/27 | NR | Mean RRT start 0.88 days;Low urine output <100ml within 8hrs post-op; | Mean RRT start 2.56 days;Cr ≥5mg/dL, or K >5.5 mEq/L | 6 |
| Boussekey2012 | France | Retrospective | Multisystem | 28/67 | 28/43 | Early: SOFA: 11.1;Late: SOFA 8.8;p=0.002 | Time from RIFLE- ‘Injury’ to RRT< 16hrs; Mean time to RRT=6hrs | Time from RIFLE- ‘Injury’ to RRT > 16hrs; Mean time to RRT=64hrs | 7 |
| Chon2012 | Korea | Retrospective | Multisystem;Sepsis | 7/36 | 9/19 | Early: SOFA 13.5;Late: SOFA 12 | Time to RIFLE ‘Injury’/‘Failure’< 24hrs; Mean time to RRT=12.5hrs | Time to RIFLE ‘Injury’/‘Failure’> 24hrs; Mean time to RRT= 42.2hrs | 7 |
| Leite2013 | Brazil | Retrospective | Multisystem | 33/64 | 67/86 | Early: APACHE2=19.2;Late: APACHE2=18.7 | Time from AKIN 3 diagnosis to RRT <24hrs | Time from AKIN 3 diagnosis to RRT >24hrs | 7 |
| Jun2014 | Australia | Prospective | Multisystem;Sepsis | 82/219 | 84/220 | Early: SOFA: 2.0;Late: SOFA 2.1 | Time from AKI diagnosis to RRT <17.6hrs | Time from AKI diagnosis to RRT>17.6hrs | 6 |
| Combes2015 | France | RCT | Post CardiacSurgery | 40/112 | 40/112 | Early: SOFA 11.5;Late: SOFA 12.0 | RRT initiated <24hrs and continuedfor min of 48hrs | Traditional indications for RRT | H |
| Yang2016 | China | Retrospective | Post CardiacSurgery | 20/59 | 80/154 | Early: APACHE2=21.4.;Late: APACHE2=23.1 | AKI in absence of traditional indications for RRT; persistence of hypotension (for more than 6 h) despite preload optimization; | Traditional indications for RRT | 7 |
| Early time to RRT <48 h | |||||||||
| Durmaz2003 | Turkey | RCT | Post CardiacSurgery | 1/21 | 7/23 | NR | Cr rise >10% from pre-op levelwithin 48hrsof surgery | Cr rise >50%from pre-op level;or Urine output <400ml/24hrs | L |
| Lyem2009 | Turkey | Prospective | Post CardiacSurgery | 5/95 | 6/90 | NR | Low urine output triggering RRT started <48hrs; Evidence of 50% increase in BUN, | Time >48hrs to start of RRT for similar markers of renal failure managed medically for minimum 48hrs | 7 |
| Bagshaw2009 | Multicountries | Prospective | Multisystem | 462/785 | 304/442 | Early: SOFA 10.9;Late: SOFA 10.7p=0.04 | RRT started <2d from ICU admission | RRT started >2d from ICU admission | 7 |
| Perez2012 | Spain | Prospective | MultisystemSepsis | 71/135 | 78/109 | Early: SOFA 12;Late: SOFA 11 | Time from ICU admission to RRT < 48h | Time from ICU admission to RRT > 48h | 5 |
| Lim2014 | Singapore | Prospective | Multisystem | 37/56 | 36/84 | Early: SOFA 11;Late: SOFA 7;p=0.001 | RRT started < 2d from admission;Traditional indications for RRT | RRT started > 2d from admission; AKIN stage 1 or 2 with indication or AKIN stage3 | 6 |
| Hyung2016 | Korea | Retrospective | MultisystemSepsis | 9/30 | 17/30 | Early: APACHE2=22.9;Late: APACHE2=21.1 | Time to RRT <26.4 h | Time to RRT >26.4 h | 6 |
| Early time to RRT <72 h | |||||||||
| Sugahara2004 | Japan | RCT | Post CardiacSurgery | 12/14 | 2/14 | Early: APACHE2=18;Late: APACHE2=19 | Mean time to RRT start 1.7d±0.8 post op; UOP <20ml/hrs ×2hrs + OR UOP <500ml/day | Mean time to RRT start 18d±0.9 post op; UOP <30ml/hrs ×3hrs ORUOP <750ml/day | L |
| Sabater2009 | Spain | Prospective | Multisystem | 21/44 | 68/104 | Early: APACHE2=26;Late: APACHE2=24 | Mean RRT start 2.2d post ICU admit (RIFLE criteria: RISK & INJURY) | Mean RRT start 6.4d post ICU admit (RIFLE criteria: FAILURE) | 7 |
| Fernandez2011 | Spain | Retrospective | Post CardiacSurgery | 59/111 | 74/92 | NR | RRT started <3d after cardiac surgery | RRT started >3d after cardiac surgery | 5 |
| Shiao2012 | China | Retrospective | Surgical | 236/436 | 143/212 | Early: SOFA 11.4;Late: SOFA 11.3 | Time to development of traditional RRT indications <3d; Mean time to start of RRT 1.4d | Traditional RRT indications AND start of RRT >3 d; Mean time to start of RRT 18d | 6 |
| Early time to RRT >72 h | |||||||||
| Gettings1999 | USA | Retrospective | Multisystem;Trauma | 25/41 | 47/59 | Early ISS = 33.0;Late ISS = 37.2 | Mean RRT start post admission10d; BUN <60mg/dl AND Oliguria, Vol overload, Electrolytes, Uremia; | Mean RRT start post admission 19d; BUN >60 mg/dL AND Oliguria, Electrolytes, Uremia; | 5 |
| Shiao2009 | China | Prospective | MajorAbdominalSurgery | 22/51 | 34/47 | Early: SOFA 8.3;Late: SOFA 8.5 | Mean Time to RRT from ICU Admit =7.3d (RIFLE criteria:RISK or pre-RISK criteria) | Mean Time to RRT from ICU Admit = 8.4d (RIFLE criteria:INJURY or FAILURE criteria) | 7 |
| Chung2009 | US | Retrospective | Severe BurnedPatients | 9/29 | 24/28 | Early: SOFA 13;Late: SOFA 13 | Mean time from admit to RRT =17 days; AKIN stage2(+shock)/3 | Mean time from admit to AKIN stage 2(+shock)/3 but not dialyzed = 23 days | 6 |
| Carl2010 | US | Retrospective | Multisystem;Sepsis | 44/85 | 42/62 | Early: APACHE2=24.8;Late: APACHE2=24.7 | Mean ICU stay prior to RRT = 6.3d;BUN <100mg/dL + AKIN stage >2; | Mean ICU stay prior to RRT = 12.3d; BUN > 100mg/dL + AKIN stage >2; | 7 |
| Hyung2012 | Korea | Retrospective | Multisystem | 75/105 | 81/105 | Early: SOFA 14.4;Late: SOFA 14.4 | Time from ICU admission to RRT =4.7d | Time from ICU admission to RRT =4.8d | 7 |
| RRT initiated base on biochemical indicators; Meantime to initiation of RRT not specified | |||||||||
| Kresse1999 | Germany | Retrospective | Multisystem | 83/141 | 102/128 | NR | BUN≤34mmol/L, sCr 380umol/L, and urine output 924 ml/24h | BUN >34mmol/L, sCr 477umol/L, and urine output 525 ml/24h | 7 |
| Splendiani2001 | Italy | Retrospective | Multisystem | 6/14 | 3/13 | NR | BUN≤ 33mmol/L | BUN> 59 mmol/L and/or severe electrolyte disturbances | 5 |
| Tsai2005 | China | Retrospective | Multisystem | 42/67 | 30/31 | NR | BUN< 29 mmol/L | BUN> 29 mmol/L | 5 |
| Liu2006 | Multicountries | Prospective | Multisystem | 43/122 | 50/121 | NR | Azotemia defined by BUN < 76mg/dL | Azotemia defined by BUN > 76mg/dL | 6 |
| Payen2009 | France | RCT | Multisystem | 20/37 | 17/39 | Early: SOFA 11.6;Late: SOFA 10.4 | RRT × 96hrs w/diagnosis of ‘sepsis’ | No RRT; unless metabolic renal failure & classic indications for RRT present | M |
| Elsevivrs2010 | Belgium | Prospective | Multisystem | 379/653 | 280/650 | Early: SOFA 9.9;Late: SOFA 8.5p=0.001 | Serum Cr >2mg/dL | No RRT | 5 |
| Konopka2011 | Poland | Retrospective | Multisystem | 17/25 | 11/12 | NR | As soon as AKI was diagnosed | After full treatment for HF and unsuccessful pharmacological treatment of complicating AKI | 5 |
| Chou2011 | China | Retrospective | Sepsis;Surgery ICU | 135/192 | 124/178 | Early: SOFA 10.8;Late: SOFA 11.6 | RIFLE criteria: RISK or pre-RISK | RIFLE criteria: INJURY or FAILURE | 6 |
| Nascimento2012 | Brazil | Retrospective | Multisystem | 9/23 | 43/63 | Early: APACHE 2= 21;Late: APACHE 2= 28 | BUN ≤26.7 mmol/L | BUN>26.7 mmol/L | 6 |
| Wu SC2012 | China | Retrospective | MultisystemSurgery | 10/20 | 45/53 | Early: SOFA 9.5;Late: SOFA 10.0 | RIFLE criteria: RISK | RIFLE criteria: INJURY or FAILURE | 5 |
| Hu2013 | China | Retrospective | Multisystem | 20//36 | 8/13 | Early: SOFA 9.3;Late: SOFA 11.5 | AKIN 1and 2 (Cr >200-300%baseline &Urine<0.5cc/kg/h for >12h) | AKIN 3 (Cr ≥354μmol/L or Cr >300% baseline & urine <0.3cc/kg/h for 24h or anuria >12h) | 5 |
| Jamle2013 | India | RCT | Multisystem | 21/102 | 13/106 | Early: SOFA 7.3;Late: SOFA 8.2 | Cr >618μmol/L | Traditional indications for RRT | M |
| Gaudry2014 | France | Retrospective | Multisystem;Sepsis | 44/91 | 29/112 | Early: SOFA 9;Late: SOFA 8P<0.01 | RRT criteria: Cr ≥300μmol/L, Urea >25mmol/L, K >6.5mmol/L,pH <7.2, Oliguria, Vol overload, | No RRT | 5 |
| Tian(461)2014 | China | Retrospective | Multisystem;Sepsis | 5/23 | 11/26 | Early: SOFA 7.6;Late: SOFA 8.4 | AKIN 1 (Cr ≥26.4μmol/L or >150- 200% baseline & urine < 0.5cc/kg/h for >6h) | No RRT | 6 |
| Tian(462)2014 | China | Retrospective | Multisystem;Sepsis | 12/31 | 14/21 | Early: SOFA 9.3;Late: SOFA 9.6 | AKIN 2 (Cr >200-300% baseline &Urine <0.5cc/kg/h for >12h) | No RRT | 6 |
| Tian(463)2014 | China | Retrospective | Multisystem;Sepsis | 31/46 | 11/13 | Early: SOFA 10;Late: SOFA 11.2 | AKIN 3 (Cr ≥354μmol/L or Cr >300% baseline & urine < 0.3cc/kg/h for 24h or anuria >12h) | No RRT | 6 |
LEGEN: AKI Acute kidney injury, RRT renal replacement therapy, Cr Creatinine, UOP Urine output, ICU Intensive Care Unit, AKIN Acute Kidney Injury Network, RIFLE Risk, Injury, Failure, Loss and End-stage, KDIGO Kidney Disease: Improving Global Outcomes, RCTs randomized clinical trials, Quality Score: The Cochrane Collaboration Risk of Bias tool for RCTs and Newcastle-Ottawa Scale for observational studies, H High quality: low risk of bias, M Medium quality: unclear risk of bias, L Low quality: high risk of bias, APACHE Acute Physiology and Chronic Health Evaluation, SOFA Sequential Organ Failure Assessment, NR Not reported.