Diabetic ketoacidosis

Manage now— do this, in order

• The order is fluid first, potassium second, insulin third, precipitant fourth — airway and breathing take precedence where the conscious level is reduced, with oxygen to keep saturations at or above 94%.
• Fluid: systolic at least 90 mmHg — 0.9% sodium chloride 1 litre IV over 1 hour, no potassium in this first litre; systolic below 90 mmHg — 500 mL over 10–15 minutes, reassess, repeat once (failure to respond to 1000 mL = coexisting shock). Then 1 L over 2 h, 1 L over 2 h, 1 L over 4 h, 1 L over 4 h, 1 L over 6 h. Be more cautious under about 25 years, in pregnancy, in older adults and in kidney or heart failure.
• Potassium before insulin: above 5.5 mmol/L — add none, recheck in 1 hour; 3.5–5.5 mmol/L — potassium chloride 40 mmol/L in each litre from the second litre onwards (premixed bags), aiming for 4.0–5.0 mmol/L; below 3.5 mmol/L — severe DKA: continuous cardiac monitoring, more than 40 mmol/L in a closely monitored setting, and insulin withheld until potassium replacement is running.Doctor / Nurse
• Insulin: soluble human insulin as a fixed-rate IV infusion at 0.1 unit/kg/hour (typically 6–10 units/hour in an adult) — no IV bolus, and never bolus a child. Continue the patient's usual long-acting basal insulin at the usual dose and time throughout — the step most often omitted.Doctor / NurseNot available at your setup — Infusion pump. No infusion pump: do not delay insulin — soluble human insulin 0.1 unit/kg intramuscularly hourly is accepted; absorption is unreliable in a vasoconstricted patient, so restore volume first.
• When the glucose falls below 14 mmol/L (250 mg/dL), start 10% glucose at 125 mL/hour alongside and in addition to the saline — never stop the insulin because the glucose has normalised: the insulin is treating the ketosis. In euglycaemic DKA the glucose infusion starts at the same time as the insulin.Doctor / Nurse
• Targets: blood ketones falling by at least 0.5 mmol/L/hour (primary); venous bicarbonate rising by at least 3.0 mmol/L/hour where ketone measurement is unavailable; glucose falling by at least 3.0 mmol/L/hour; potassium held at 4.0–5.5 mmol/L. If ketones are not falling, check the plumbing before the pharmacology — pump on, line connected and patent, cannula not tissued, correct insulin concentration (never confuse U-100 and U-40) — then increase the infusion by 1.0 unit/hour increments hourly.
• Monitor: capillary glucose and blood ketones hourly; venous gas at 1 hour, 2 hours, then 2-hourly; laboratory electrolytes at least 4-hourly; vital signs and conscious level at least hourly, with hourly GCS in all children and adolescents specifically to detect cerebral oedema; urine output and fluid balance hourly.
• Do not give IV bicarbonate (threshold for even considering it: pH below 6.9–7.0, as isotonic 1.26%, and never to a child). A falling conscious level while the biochemistry improves is cerebral oedema until proven otherwise — treat before imaging. Do not track urine ketones: they may rise while the patient improves.
• Supportive care and the precipitant: nasogastric tube if obtunded or persistently vomiting; urinary catheter if no urine within 2–4 hours; low-molecular-weight heparin in older or high-risk individuals; broad-spectrum antibiotics once cultures are taken if infection is suspected; examine chest, abdomen, skin and — socks off — the feet.Not available at your setup — Blood culture.