What is the management for a 38-week pregnant patient with hyperglycemia, metabolic acidosis, ketonuria, hypokalemia, and blurred vision?

Management of Diabetic Ketoacidosis in a 38-Week Pregnant Patient

This patient requires immediate hospitalization for treatment of diabetic ketoacidosis (DKA), which is a life-threatening emergency requiring intravenous insulin therapy, fluid resuscitation, and potassium replacement.

Initial Assessment and Diagnosis

The patient presents with classic signs of DKA:

• Hyperglycemia (glucose 235 mg/dL)
• Ketonuria (2+ ketones in urine)
• Metabolic acidosis (anion gap of 14)
• Hypokalemia (potassium 3.2 mEq/L)
• Blurry vision (symptom of hyperglycemia)
• 38 weeks pregnant (high-risk situation)

This clinical picture is consistent with DKA in pregnancy, which is particularly dangerous as it carries high risk of fetal mortality if not promptly treated.

Management Algorithm

1. Immediate Interventions

• Hospital Admission: Immediate hospitalization is required, preferably to a high-acuity setting with obstetric capabilities.
• Continuous Fetal Monitoring: Due to the high risk of fetal compromise in DKA.
• Intravenous Access: Establish large-bore IV access for fluid and medication administration.

2. Fluid Resuscitation

• Begin with isotonic saline (0.9% NaCl) at 500 mL/hr for the first 2-3 liters 1.
• After initial volume resuscitation, transition to 5% glucose in 0.45% saline when blood glucose falls below 250 mg/dL 1.
• Monitor fluid status carefully to avoid fluid overload, which could precipitate pulmonary edema.

3. Insulin Therapy

• Continuous intravenous insulin infusion is the preferred treatment for DKA in pregnancy 1.
• Begin with continuous IV regular insulin at 0.1 units/kg/hour without an initial bolus 1.
• Continue insulin infusion until resolution of ketoacidosis (glucose <200 mg/dL, bicarbonate >18 mEq/L, pH >7.3) 1.

4. Potassium Replacement

• The patient's potassium is 3.2 mEq/L, indicating hypokalemia which requires immediate correction.
• Begin potassium replacement once adequate urine output is established 1.
• Add 20-40 mEq/L of potassium (2/3 KCl and 1/3 KPO₄) to IV fluids 1.
• Target serum potassium level of 4-5 mEq/L 1.

5. Monitoring

• Check capillary blood glucose hourly 1.
• Monitor serum electrolytes, particularly potassium, every 2-3 hours initially 1.
• Check bicarbonate, sodium, and chloride every 4-6 hours 1.
• Continuous maternal and fetal monitoring due to high risk of complications 1.

6. Obstetric Management

• Consult obstetrics immediately for assessment of fetal well-being and consideration of delivery.
• At 38 weeks gestation with maternal DKA, delivery may be indicated if maternal condition is stabilized 1.
• The risks of complications are significantly higher in pregnant women with diabetes, including increased risk of cesarean delivery, eclampsia, and perinatal mortality 1.

Special Considerations in Pregnancy

• DKA can occur at lower blood glucose levels in pregnancy (even <200 mg/dL) 1.
• Ketosis can develop rapidly in pregnant women with type 1 diabetes, even with only moderately elevated blood glucose 1.
• Fetal mortality is high in untreated DKA during pregnancy.
• Maternal hyperglycemia induces fetal hyperinsulinism, which increases risk of neonatal hypoglycemia after delivery 1.

Transition After Resolution of DKA

Once DKA resolves (glucose <200 mg/dL, bicarbonate >18 mEq/L, pH >7.3, anion gap <12 mEq/L):

1. Transition from IV insulin to subcutaneous insulin regimen 1.
2. Continue glucose monitoring to maintain target levels of 5-10 mmol/L (90-180 mg/dL) 1.
3. Address the precipitating cause of DKA (infection, medication non-adherence, etc.).

Pitfalls to Avoid

• Delayed treatment: DKA in pregnancy is a medical emergency with high fetal mortality.
• Inadequate potassium replacement: Hypokalemia can lead to cardiac arrhythmias.
• Rapid correction of osmolality: Can lead to cerebral edema; limit osmolality reduction to 3 mOsm/kg/h 1.
• Premature discontinuation of IV insulin: Continue until acidosis resolves.
• Neglecting fetal monitoring: Continuous fetal monitoring is essential.

This patient requires immediate, aggressive management of DKA with particular attention to maternal and fetal well-being given the advanced gestational age.