75 year old presents to emergency with a 2 day history nausea, vomiting, abdominal pain and diarrhoea. He has not been tolerating oral fluids and is currently confused with a GCS of 14. He has a past medical history of heart failure, atrial fibrillation and chronic kidney injury. He is on digoxin, metoprolol and an ace inhibitor. Clinically he is dehydrated and in slow atrial fibrillation. Blood test shows he has acute kidney injury.