Coma due to diabetic ketoacidosis in diabetes patients is a dangerous complication that can seriously affect the patient’s life. The main cause leading to this condition is insulin deficiency, resulting in severe disturbances in the metabolism of proteins, lipids, and carbohydrates.
1. What is diabetic ketoacidotic coma?
Diabetic ketoacidotic coma is a medical emergency, a severe complication of significant insulin deficiency in diabetes patients. The pathogenic mechanisms include three dangerous metabolic disorders: hyperglycemia, acidosis due to the presence of keto acids in the blood, and electrolyte imbalances.
1.1 Hyperglycemia
Due to the state of insulin deficiency combined with increased production of insulin-antagonistic hormones, glucose production in the blood increases, leading to decreased glucose utilization in peripheral tissues, resulting in elevated blood glucose levels.
1.2 Ketoacidosis
The lack of insulin and increased insulin-antagonistic hormones (glucagon, catecholamines, cortisol) enhance the process of lipolysis, releasing free fatty acids and forming keto acids (acetone, acetoacetic acid, and 3-beta-hydroxybutyric acid). As a result, the body’s alkaline reserves decrease, leading to severe acidosis.
1.3 Fluid and Electrolyte Disturbance
Diabetic patients leading to ketoacidosis will cause osmotic polyuria due to increased glucose in the urine and result in severe dehydration and electrolyte loss in the body.
2. Favorable Factors Causing Ketoacidosis
Many diabetic patients develop ketoacidosis with unclear triggering factors.
- Type 1 diabetic patients receiving insulin who suddenly stop insulin, or who are on insulin but have additional favorable factors leading to ketoacidosis-related comas.
- Type 2 diabetic patients who do not have good glucose control along with favorable factors leading to ketoacidosis.
Favorable factors include:
Infections in the body such as pneumonia, meningitis, intestinal infections, urinary infections…
- Trauma
- Stroke
- Myocardial infarction
- Cerebrovascular accident
- Use of drugs with cocaine…
3. Diagnosis of Ketoacidosis in Diabetic Patients
3.1 Clinical Signs and Symptoms of the Disease
- Patients often feel nausea and vomit a lot.
- Feeling thirsty, drinking more water, and urinating more frequently with larger volumes than normal.
- Feeling fatigued, anorexic.
- Changes in vital signs such as rapid heartbeat, hypotension, rapid shallow breathing with Kussmaul breathing pattern.
- Signs of dehydration, dry and hot skin.
- Altered or decreased consciousness such as drowsiness, lethargy, or coma.
- One very specific sign is that the patient’s breath has a ketone odor.
3.2 Signs in laboratory tests
- Blood glucose > 13.9 mmol/L.
- Bicarbonate (plasma) < 15 mEq/L.
- Arterial blood pH < 7.2
- Presence of ketone bodies in the blood and urine.
4. Treatment of ketoacidosis in diabetic patients
4.1 Rehydration
The presence of glucose in the urine causes osmotic diuresis, leading to dehydration and electrolyte loss in all diabetic patients with ketoacidosis. Rehydration is very important; the rehydration protocol is as follows:
- Hour 1: 0.9% NaCl solution: 15-20 mL/kg (500 mL/m² body surface/hour). If the patient is elderly or has concomitant heart disease, this volume may be lower.
- Hour 2: 0.9% NaCl solution 15 mL/kg. In cases of hypernatremia or congestive heart failure, use 0.45% hypotonic NaCl solution.
- Hour 3: Reduce the infusion rate to 7.5 mL/kg/hour (in adults) or from 2 – 2.5 mL/kg/hour (in young children). The solution used during this stage is usually 0.45% hypotonic NaCl solution.
- Hour 4: Depending on clinical progression, assess the fluid intake and output.
When the patient’s blood glucose level is around 13.9 mmol/L (250 mg/dL), 0.9% NaCl can be replaced with 5% glucose solution while continuing to infuse insulin or use an isotonic saline-glucose solution. Rehydration should continue until the patient’s condition improves, nausea decreases, and they can ingest oral sugars.
4.2 Use of Insulin
The main mechanism causing ketoacidosis in diabetic patients is still due to severe insulin deficiency. Therefore, insulin replacement is a necessary and important factor in treating ketoacidosis in diabetic patients.
The type of insulin used in emergencies is rapid-acting insulin (also known as regular insulin) and is administered intravenously (by injection or infusion). The treatment dosage of insulin is as follows:
- Initial dose of 0.1-0.15 IU/kg/hour (intravenous injection)
- Then continue intravenous infusion at a dose and rate of 0.1 IU/kg/hour.
Some notes when needing to change the dose and infusion rate of insulin:
- If the patient has no response after 2 – 4 hours of insulin use, and blood glucose does not decrease by 3.9 mmol/L/hour, the infusion dose must be doubled.
- If blood glucose levels < 13.9 mmol/L (250 mg/dL), then the insulin infusion dose should be reduced, and 5% glucose solution (Dextrose 5%) should be added.
Conditions for transitioning from intravenous insulin to subcutaneous insulin when the patient is awake and can eat orally:
- Clinical signs improve.
- Blood pH > 7.3, plasma bicarbonate concentration > 18 mEq/L, electrolyte levels return to normal.
- The patient can eat and has no nausea or vomiting.
- Precipitating factors for the condition (such as infections, trauma, etc.) have been well-managed.
- When switching to subcutaneous injections, intermediate-acting insulin should be used, and the dosage of insulin should depend on blood glucose levels.
4.3 Potassium Replacement
A common electrolyte disorder in patients with ketoacidosis is hypokalemia (incidence 50%). The cause is potassium loss through the kidneys (due to osmotic diuresis, due to loss of reabsorption ability) or due to vomiting, diarrhea, etc. Consider the following factors before proceeding with potassium replacement:
- Does the patient have kidney dysfunction? If the patient urinates ≥ 60ml/hour in the first hour, kidney function is still good.
- What is the current potassium level?
- Monitor the electrocardiogram.
Indications for potassium replacement:
- Serum potassium > 5.5 mmol/L: Do not administer potassium.
- Serum potassium from 3.5 to 5.5 mmol/L: replace with 20 mmol K+/liter of infusion.
- Serum potassium < 3.5 mmol/L: replace with 40 mmol K+/liter of infusion.
- Absolutely do not use intravenous insulin if potassium levels are below 3.3 mmol/L.
5. Considerations in the treatment of diabetic ketoacidosis in patients with diabetes
- It is essential to identify and treat the precipitating factors of diabetic ketoacidosis in patients with diabetes such as trauma, stress, infections…
- Patients need comprehensive care, especially when in a coma.
Prevent common complications during treatment.
- Recurrence of diabetic ketoacidosis has a much worse prognosis.
- Cerebral edema and even death can occur. To ensure safety, blood glucose levels should be maintained around 11.1 mmol/L (200 mg/dL) during the first 12-24 hours.
- Nausea and vomiting can cause food aspiration, potentially leading to aspiration pneumonia.
- Hypoglycemia may occur. To prevent this, blood glucose should be maintained at 11.1 mmol/L – 13.9 mmol/L.
- Replacement fluids (especially isotonic saline) may worsen congestive heart failure.
6. Prevention of diabetic ketoacidosis in patients with diabetes
- Patients need to be instructed on how to self-monitor their blood glucose levels.
- Seek medical attention immediately if abnormal signs occur such as nausea, fever, abdominal pain, diarrhea, or high blood glucose levels… or if another condition such as infection, trauma, or pregnancy arises.
- Adhere to treatment, do not reduce insulin dosage independently, or discontinue medication even when experiencing another illness.
