Sodium Bicarbonate for Critically Ill Patients With Metabolic Acidosis and Acute Kidney Injury

Inclusion Criteria: 1. Adult ≥ 18 years 2. Critically ill patients (requiring treatment on an ICU or IMC) 3. Metabolic acidosis, defined as all of the following: 1. Arterial pH ≤7.25 2. PaCO2 \< 6.5kPa (\<49 mmHg) 3. Standard bicarbonate ≤20 mmol/L 4. Standard Base Excess \<-2 4. AKI stage 2 or 3 of the KDIGO classification 5. Written informed consent of the patient or legal representative or authorized representative or emergency inclusion (according to Article 35 EU-Regulation 536/2014) Exclusion Criteria: 1. Pregnant or breastfeeding patients 2. Respiratory acidosis (acute or chronic) \[dynamic, and if corrected, patient may be reconsidered for the trial\] 3. Patients on KRT, or KRT immediately indicated and treating clinician(s) unwilling to defer 4. Deemed unsuitable for KRT 5. High output stoma/ileostomy 6. Percutaneous biliary drainage 7. End stage kidney failure defined as documented eGFR \<15ml/min/1.73m 2 prior to onset of this acute illness or end stage kidney disease (ESKD) on dialysis 8. Known renal tubular acidosis 9. Diabetic ketoacidosis 10. High anion gap acid poisoning (e.g. polyethylene glycol (PEG), aspirin, methanol) 11. Symptomatic hypocalcaemia (Ionized calcium \<1.05 mmol/L)\[dynamic, and if corrected, patient may be reconsidered for the trial\] 12. Hypernatremia (plasma sodium \>150 mmol/L)\[dynamic, and if corrected, patient may be reconsidered for the trial\] 13. Severe hypokalemia (potassium \<3.0 mmol/L)\[dynamic, and if corrected, patient may be reconsidered for the trial\] 14. Death perceived as imminent 15. Known hypersensitivity to sodium bicarbonate or EDTA (Disodiumedetate) 16. Previously randomized into ESCALATE