Indications for Renal Replacement Therapy (RRT) 
This document outlines the key indications for initiating renal replacement therapy (RRT).  

Summary: AEIOU Mnemonic 

A – Acidosis (Metabolic) 
Severe metabolic acidosis refractory to medical therapy 
Typically pH ≤ 7.1–7.2 
Associated with haemodynamic instability and arrhythmias 

E – Electrolyte abnormalities 
Refractory hyperkalaemia (K+ ≥ 6.0–6.5 mmol/L) 
Any potassium level with ECG changes 
Failure of medical management (calcium, insulin/dextrose, beta-agonists) 

I – Intoxications (Toxin clearance) 
Dialysable toxins such as lithium, methanol, ethylene glycol, salicylates 
Most effective for substances with low molecular weight and protein binding 

O – Overload (Fluid overload) 
Pulmonary oedema refractory to diuretics 
Worsening oxygenation or ventilatory difficulty 
Positive fluid balance contributing to organ dysfunction 

U – Uraemia 
Uraemic encephalopathy 
Pericarditis 
Bleeding due to platelet dysfunction 
Severe nausea or vomiting 

ICU Considerations 

RRT initiation is a clinical decision and should not be based on creatinine levels alone. Factors such as haemodynamic stability, ventilatory requirements, and overall trajectory should be considered. 
Modalities include Continuous Renal Replacement Therapy (CRRT) for unstable patients, Intermittent Haemodialysis (IHD) for stable patients, and Sustained Low-Efficiency Dialysis (SLED) as an intermediate option.