Table 1. Summary of study characteristics of included studies on renal function.
| Author [ref], study period, country | Study design | Intervention | Number of patients | AKI definition / renal parameters assessed | Time of measurement | Incidence AKI | Quality assessment | |
|---|---|---|---|---|---|---|---|---|
| Cooled | Control | |||||||
| Akisu et al. [16], 2000–2001, Turkey | Single centre; randomized controlled trial | Head cooling | 11 cooled vs 10 control | ND | ND | 5 of 11 | 5 of 10 | Moderate |
| Eicher et al. [17], ND, Canada; USA | Multicentre; randomized controlled trial | Whole body cooling | 32 cooled vs 33 control | Urine output <1 mL/kg/h, hematuria, creatinine >150 μmol/L | Any time during hospitalization | 2 of 31 | 3 of 31 | Moderate |
| Gluckman et al. [18], 1999–2002, USA; Canada; UK; New Zealand | Cool Cap study; multicentre; randomized controlled trial | Head cooling | 116 cooled vs. 118 control | Urine output <0.5 ml/kg/h for at least 24 h or maximum serum creatinine >90 μmol/L | In first 7 days of life | 73 of 112 | 83 of 118 | Moderate |
| Gunn et al. [19], 1996–1997, New Zealand | Single centre; randomized controlled trial | Head cooling plus either minimal or mild systemic cooling | 12 cooled vs 10 control | Urine output <0.5 ml/kg/h for at least 24 h, proteinuria, hematuria, maximum serum creatinine levels | ND | 12 of 12 | 10 of 10 | High |
| Roka et al. [5], 2005–2006, Hungary | Part of TOBY trial; single centre; randomized controlled trial | Whole body cooling | 12 cooled vs. 9 control | Rate of diuresis and serum creatinine levels | 6h, 24h, 48h, 72h (after birth) | 3 of 12 | 7 of 9 | High |
| Shankaran et al. [20], 2000–2003, USA | NICHD study; multicentre; randomized controlled trial | Whole-body cooling | 102 cooled vs. 106 control | Oliguria or anuria | During hospital course | 16 of 102 | 23 of 106 | High |
| Simbruner et al. [21], 2001–2006, Austria; Germany | Neo.nEURO. network; multicentre; randomized controlled trial | Whole body cooling | 64 cooled vs. 65 control | Urine output <0.5 ml/kg/hour for at least 24h and maximal serum creatinine levels of >90 μmol/L | During intervention period | 16 of 62 | 26 of 63 | High |
| Tanigasalam et al.[22], 2013–2015, India | Single centre; randomized controlled trial | Whole body cooling | 60 cooled vs. 60 control | AKIN criteria: stage 1 (increase in serum creatinine >26.5 μmol/L or serum creatinine >150–200% from baseline), stage 2 (increase in serum creatinine >200–300% from baseline), stage 3 (increase in serum creatinine >300% from baseline or serum creatinine >353.6 μmol/L with an acute rise of >44.2 μmol/L) | 6h, 36h, 72h (after birth) | 19 of 60 | 36 of 60 | High |
| Zhou et al. [23], 2003–2005, China | Multicentre; randomized controlled trial | Head cooling | 100 cooled vs. 94 control | Creatinine >120 μmol/L, blood urea nitrogen >8 mmol/L or urine output <1 mL/kg/h | 12h, 24h, 48h, 72h (after treatment) | 21 of 100 | 19 of 94 | High |
ND = not described.