A randomised controlled trial is recommended to compare DyeVert Systems with standard care. The aim of this research would be to address uncertainties about whether using DyeVert Systems reduces AKI incidence and rate of renal replacement therapy after using contrast media. This must include people with stage 4 chronic kidney disease (with an estimated glomerular filtration rate [eGFR] under 30 ml/min/1.73 m2), who are at risk of AKI and need elective coronary or peripheral angiography.