Diabetic Ketoacidosis (DKA): Diagnosis and Management
Written by Dr. Muhammad Salar Raza · Manually reviewed by Dr. Muhammad Salar Raza · Content updated
Clinical Pathway
Diagnose DKA with diabetes or hyperglycemia, ketosis and metabolic acidosis; remember that SGLT2-associated DKA can occur without marked hyperglycemia. Start intravenous isotonic saline or balanced crystalloid, adapting the rate to hydration, cardiac and renal status. Check potassium before insulin: if potassium is below 3.5 mmol/L, replace it and delay insulin until potassium is above 3.5 mmol/L. Follow a monitored insulin and electrolyte protocol, adding dextrose as glucose falls so insulin can continue to clear ketones. Assess resolution using ketones and acid-base recovery rather than glucose or the anion gap alone. Treat the precipitant and overlap subcutaneous insulin before stopping the infusion.
Clinical Reasoning
Volume replacement restores perfusion, while insulin can lower potassium rapidly and cause dangerous hypokalemia. Total body potassium is depleted even when the initial measured concentration is normal or high. Frequent glucose, electrolyte, ketone and acid-base measurements guide treatment. Bicarbonate is not routine treatment and is considered only in severe acidosis under the local protocol. Hyperchloremic acidosis after treatment can make the anion gap misleading as a resolution criterion. Search for infection, missed insulin and other precipitants; consider euglycemic DKA when a patient taking an SGLT2 inhibitor has ketosis and acidosis.
Sample MCQ
A 19-year-old woman with type 1 diabetes presents with vomiting, deep rapid breathing, glucose 460 mg/dL, pH 7.18, and positive serum ketones. Serum potassium is 4.0 mmol/L. What is the most appropriate first step in management?
- AIntravenous isotonic saline infusion
- BSubcutaneous rapid-acting insulin
- CIntravenous sodium bicarbonate
- DOral rehydration solution
Correct Answer: Intravenous isotonic saline infusion
Intravenous isotonic fluid is the best initial choice among these options for a dehydrated patient with DKA. Check potassium and follow a monitored insulin and electrolyte protocol. Bicarbonate is not indicated routinely at pH 7.18. Selected uncomplicated mild or moderate cases can receive subcutaneous rapid-acting insulin in an appropriately monitored setting, but oral rehydration alone is inadequate here.
Guidelines and further reading
Deep Dive Walkthroughs
Read full case walkthroughs with option-by-option analysis for this topic:
Related Clinical Topics
Insulin Deficiency: Causes, Diagnosis and Management
Insulin deficiency is a metabolic condition characterized by inadequate production or complete absence of insulin from the pancreatic beta cells, resulting in impaired glucose utilization and elevated blood glucose levels. This typically leads to a diagnosis of Type 1 Diabetes Mellitus or represents a late stage of other pancreatic diseases. The mainstay of treatment is lifelong exogenous insulin replacement, administered through multiple daily injections or an insulin pump, to mimic physiological insulin secretion. Management also involves diligent blood glucose monitoring, carbohydrate counting, dietary adjustments, and regular physical activity to optimize glycemic control and prevent complications. Key symptoms include polyuria (frequent urination), polydipsia (excessive thirst), polyphagia (increased hunger), and unexplained weight loss. Patients often experience fatigue, blurred vision, recurrent infections, and in acute severe cases, symptoms of diabetic ketoacidosis such as nausea, vomiting, abdominal pain, and rapid, deep breathing (Kussmaul respirations).
Primary Hypothyroidism: Diagnosis and Management
Primary hypothyroidism is characterized by an underactive thyroid gland, resulting in decreased production of thyroid hormones. Common symptoms include fatigue, weight gain, cold intolerance, constipation, and dry skin. The diagnosis is established by finding an elevated Thyroid Stimulating Hormone (TSH) and a low free Thyroxine (Free T4). The standard treatment is daily replacement therapy with synthetic levothyroxine (T4). The goal of therapy is to normalize the serum TSH level, which should be rechecked 6-8 weeks after initiating or adjusting the dose.
Gestational Diabetes Mellitus (GDM): Screening and Management
Screen all pregnant women at 24-28 weeks with a 75 g oral glucose tolerance test, or earlier when risk factors such as obesity or previous GDM exist. First-line management is medical nutrition therapy with structured physical activity and daily glucose self-monitoring. If fasting or postprandial targets are repeatedly exceeded despite lifestyle measures, start insulin, with metformin as an accepted alternative in many guidelines. Monitor fetal growth because GDM drives macrosomia, and plan delivery around 38-39 weeks when medication is required. After delivery, insulin needs fall sharply; arrange a 75 g OGTT at 6-12 weeks postpartum because about half of women with GDM later develop type 2 diabetes.
SMLE Preparation Resources
Master the 2026 SMLE
Explore more clinical protocols in the SMLEREVISE Clinical Knowledge Library.
Try the QBank & Scaled Mocks