Reduced renal function, may be acute or chronic. An estimated glomerular filtration rate (eGFR) less than 90mL/minute/1.73m² indicates a degree of renal impairment in chronic kidney disease. For the purposes of this guideline the GDG defined “severe renal impairment” as an estimated glomerular filtration rate (eGFR) less than 30mL/minute/1.73m².