Disease Description (Causes and Symptoms)
- Definition: Diabetic ketoacidosis (DKA) is an acute complication in which hyperglycemia, conversion of free fatty acids into ketone bodies in the liver (ketosis), and metabolic high-acid acidosis occur simultaneously due to insulin deficiency and elevated counterregulatory stress hormones (glucagon, catecholamines, etc.). It occurs mainly in type 1 diabetes but can also occur in type 2 diabetes.
- Summary of pathophysiology: Insulin deficiency → reduced tissue utilization of glucose (hyperglycemia) → increased lipolysis → increased production of ketone bodies (acetoacetic acid, beta-hydroxybutyric acid) → metabolic acidosis and electrolyte abnormalities (particularly potassium). Dehydration and electrolyte loss (glucose excretion in the urine) may worsen circulatory failure.
- Main symptoms: Polyuria and polydipsia (thirst), dry mouth, fatigue, vomiting, abdominal pain, breathing (Kussmaul respirations) and fruity-smelling breath, tachycardia and hypotension (dehydration), and altered consciousness (in severe cases).
Treatment Methods and Precautions
- Initial principles: Rapid fluid replacement, intravenous insulin therapy, correction of electrolytes (particularly potassium), simultaneous treatment of precipitating factors (such as infection), and close monitoring.
- Fluid therapy: Generally, replacement is started with normal saline (0.9% NaCl; usually about 1 L during the first hour), followed by maintenance with 0.45% or 0.9% saline depending on hemodynamic and electrolyte status. Excessive or rapid fluid administration may increase the risk of cerebral edema, particularly in children, so caution is needed.
- Insulin: Continuous infusion of intravenous short-acting insulin (regular insulin) is standard (for example, an initial 0.1 U/kg bolus followed by an infusion of 0.1 U/kg/hr, or starting at 0.14 U/kg/hr without a bolus). When blood glucose falls to around 200 mg/dL, glucose (such as 5% D/W) is administered together to maintain blood glucose at 150–200 mg/dL while continuing to resolve the acidosis and ketosis.
- Potassium management: In DKA, total body potassium is decreased, although the initial blood potassium level may be normal or high. If blood potassium is <3.3 mEq/L before insulin administration, potassium replacement should be given first (without delay), followed by initiation of insulin. If potassium is 3.3–5.2, replacement is generally given (for example, 20–40 mEq/L IV); if it is >5.2, replacement is initially withheld and follow-up testing is performed.
- Other electrolytes and acidosis: Bicarbonate administration should be considered only in limited circumstances when pH <6.9. If hypophosphatemia causes muscle weakness or respiratory failure, phosphate replacement may be considered.
- Transfer and monitoring: For severe cases (including coma, shock, rapidly developing electrolyte abnormalities, or respiratory failure), treatment in an intensive care unit is recommended. Blood glucose, electrolytes, renal function, acid-base status, blood pressure, heart rate, and urine output should be monitored frequently.
- Treatment of precipitating factors: Treat causes such as infection, myocardial infarction, surgery, and medications (steroids, diuretics, SGLT2 inhibitors, etc.) at the same time. In particular, ketosis associated with SGLT2 inhibitors may occur even when blood glucose is not markedly elevated, so caution is needed.
- Timing of transition: When the patient can eat, pH is >7.3, bicarbonate has normalized, ketones have become negative (or are trending toward negative), and blood glucose is stable, discontinue intravenous insulin and switch to subcutaneous insulin (overlap for 1–2 hours after administering subcutaneous insulin).
- Precautions regarding complications: Arrhythmia due to hypokalemia, pulmonary edema/cerebral edema due to excessive fluid administration (particularly in children), infection/sepsis, and acute kidney injury.
- Lifestyle management (self-management): Administer insulin regularly as usual, self-monitor blood glucose and ketones (particularly when ill or vomiting), follow “sick-day rules,” replace fluids and electrolytes, and understand when to contact a medical institution immediately.
Checklist Before an Outpatient Visit (Items to Prepare, Things to Confirm, and Sample Questions)
- Items to prepare:
- List of currently used medications (including insulin type, dose, and administration times)
- Recent blood glucose log (self-monitoring results) and continuous glucose monitoring data (if available)
- Record of the time of the last meal and symptom onset, and whether vomiting, abdominal pain, or fever occurred
- Recent weight changes, changes in urine output, and urine/blood ketone test results (if available)
- Past medical history (including heart and kidney disease) and recent hospitalization or infection history
- Items to confirm before the visit:
- Time of symptom onset and progression (frequency of vomiting and changes in consciousness)
- Recent medication changes (particularly steroids, diuretics, and SGLT2 inhibitors)
- Urine and blood ketone test results (positive/level)
- History of diabetes education (such as self-administered insulin injections and how to measure ketones)
- Information to tell the doctor first during the outpatient visit (medical history points):
- Whether vomiting prevents you from eating food or taking medication
- Whether urine output has decreased markedly or whether high fever or difficulty breathing is present
- Recent symptoms of infection (such as cough or urinary tract symptoms) or a severe stressful event
Examples of General Questions to Ask the Doctor
- "What do you think was the main precipitating cause of this hospitalization?"
- "How should the dose and type of insulin I am currently using be adjusted?"
- "What should I watch for to reduce the risk of complications (cerebral edema, low potassium, etc.)?"
- "What lifestyle measures can help prevent recurrence in the future (including when to test ketones and when to go to the hospital)?"
- "What are the main side effects of this medication (or treatment), and what should be monitored?"
Examples of Disease-Specific Questions
- "My current blood potassium is X mEq/L (or I have not had my potassium tested). What is the plan for insulin administration? What criteria will be used for potassium replacement?"
- "My blood glucose has fallen to about 200 mg/dL. When will the glucose solution be started, and when will intravenous insulin be discontinued?"
- "If ketosis occurs while taking an SGLT2 inhibitor, can a medication in this class be restarted later?"