BackgroundDiabetic ketoacidosis (DKA) and hyperosmolar hyperglycaemic state (HHS) are medical emergencies requiring prompt assessment and management to avoid complications.AimsTo examine adherence to the hospital DKA/HHS insulin infusion protocol, assess outcomes in patients admitted with DKA or HHS, and determine if improvements have been observed from a similar audit in 2016.MethodsAn audit was conducted on 40 patients admitted to Shellharbour Hospital with DKA or HHS. Protocol adherence was assessed in the domains of fluid replacement, potassium replacement, use of the correct insulin infusion schedule, timing of commencement of dextrose infusion and appropriate transition to subcutaneous insulin. The outcomes assessed included length of hospital stay, duration of insulin infusion, time to euglycaemia, intensive care unit (ICU) transfer, overlap between insulin infusion and subcutaneous insulin, diabetes team review and incidence and management of hypoglycaemia.ResultsThe proportion of cases that adhered to the components of the insulin infusion protocol is as follows: fluid replacement (40%), potassium replacement (72.5%), correct insulin schedule (82.5%), appropriate commencement of intravenous dextrose (80%) and appropriate transition to subcutaneous insulin (87.5%). Appropriate overlap between insulin infusion and subcutaneous insulin occurred in 62.5% of patients. Eighty‐five per cent of patients were reviewed by the diabetes team. Three per 40 patients experienced hypoglycaemia, and none of the three patients was treated as per protocol. Compared to the 2016 audit, there was a significant improvement in potassium replacement but a decrease in appropriate fluid replacement.ConclusionThis audit highlights areas in DKA/HHS management requiring improvement. These include fluid and potassium replacement and appropriate overlap between subcutaneous insulin and insulin infusion.