What is the recommended treatment plan for an adult patient with a history of diabetes and recent diabetic ketoacidosis episode, who also presents with psychiatric symptoms and now has negative ketone levels?

Management After DKA Resolution with Negative Ketones

Once ketones are negative and DKA has resolved, transition to subcutaneous insulin 2-4 hours before stopping IV insulin, continue diabetes management with close glucose monitoring, address any psychiatric symptoms with careful antipsychotic selection, and ensure structured discharge planning with patient education. 1, 2

Confirming Complete DKA Resolution

Before transitioning care, verify all resolution criteria are met:

• Glucose <200 mg/dL 1, 2
• Serum bicarbonate ≥18 mEq/L 1, 2
• Venous pH >7.3 1, 2
• Anion gap ≤12 mEq/L 1, 2
• Negative or trace ketones (β-hydroxybutyrate <0.5 mmol/L preferred over urine ketones) 1

The patient must also be hemodynamically stable, able to tolerate oral intake, and have adequate urine output before transitioning from IV to subcutaneous insulin. 2

Transition from IV to Subcutaneous Insulin

The most critical step is administering basal insulin (glargine or detemir) subcutaneously 2-4 hours BEFORE discontinuing the IV insulin infusion. 3, 1, 2 This overlap period allows the long-acting insulin to be absorbed and prevents rebound hyperglycemia and recurrent ketoacidosis. 3, 2

Calculating Subcutaneous Insulin Dose

• Estimate total daily insulin requirements from the average IV insulin infusion rate over the preceding 12 hours 3
• For example, if the patient received an average of 1.5 units/hour, the estimated daily dose is 36 units (1.5 × 24) 3
• Divide this into basal (50%) and prandial (50%) components, adjusting based on nutritional status 3

Multiple-Dose Insulin Regimen

• Start a combination of short/rapid-acting insulin (with meals) and intermediate/long-acting basal insulin 3, 2
• Continue IV insulin for 1-2 hours after administering subcutaneous insulin to ensure adequate overlap 2
• Monitor glucose every 2-4 hours initially after transition 2

Common pitfall: Stopping IV insulin when glucose normalizes without prior subcutaneous basal insulin administration is the most frequent error leading to DKA recurrence. 2, 4 Ketoacidosis takes longer to resolve than hyperglycemia, and premature insulin cessation causes recurrent ketosis. 1, 5, 4

Ongoing Diabetes Management

Glucose Monitoring and Targets

• Check blood glucose every 2-4 hours while fasting, then before meals and at bedtime once eating 2
• Target pre-meal glucose <140 mg/dL and random glucose <180 mg/dL for most general medicine patients 3
• Acceptable range of 72-216 mg/dL, though the lower limit (72 mg/dL) may increase hypoglycemia risk 3

Electrolyte Monitoring

• Continue monitoring potassium closely, as insulin drives potassium intracellularly 2
• Hypokalaemia occurs in approximately 50% of patients during DKA treatment and severe hypokalaemia (<2.5 mEq/L) is associated with increased mortality 3

Identifying Precipitating Factors

• Infection is the most common precipitating cause (30-50% of cases), particularly urinary tract infection and pneumonia 6
• Other causes include non-compliance with insulin, intercurrent illness, myocardial ischemia, pancreatitis, and psychological stress 6
• Treat any identified precipitating cause to prevent recurrence 3, 5

Managing Psychiatric Symptoms

If the patient requires antipsychotic medication for psychiatric symptoms, exercise extreme caution given the recent DKA episode:

Antipsychotic Selection and Monitoring

• Atypical antipsychotics including risperidone have been associated with hyperglycemia, ketoacidosis, hyperosmolar coma, and death 7
• Patients with established diabetes who are started on atypical antipsychotics must be monitored regularly for worsening glucose control 7
• Perform fasting blood glucose testing at the beginning of antipsychotic treatment and periodically during treatment 7
• Monitor for hyperglycemia symptoms: polydipsia, polyuria, polyphagia, and weakness 7

Risk-Benefit Consideration

• Chronic antipsychotic treatment should be reserved for patients with chronic illness known to respond to antipsychotics, and for whom alternative, equally effective but potentially less harmful treatments are not available 7
• Use the smallest effective dose and shortest duration producing satisfactory clinical response 7
• In some cases, hyperglycemia has resolved when the atypical antipsychotic was discontinued; however, some patients required continuation of anti-diabetic treatment despite discontinuation 7

Critical consideration: The combination of diabetes history, recent DKA, and need for antipsychotic medication creates substantial metabolic risk. If antipsychotic treatment is deemed necessary, intensify glucose monitoring (at least daily initially) and consider consultation with psychiatry and endocrinology for collaborative management.

Discharge Planning and Patient Education

Pre-Discharge Education Requirements

The American Diabetes Association recommends reviewing the following areas before discharge: 3

• Identification of outpatient diabetes care provider 3
• Recognition, treatment, and prevention of hyperglycemia and hypoglycemia 3
• Self-monitoring of blood glucose technique and home glucose goals 3
• When to call the provider (specific sick-day rules) 3
• Insulin administration technique (if applicable) 3
• Healthy food choices with referral to outpatient dietitian 3

Sick-Day Management

• During acute illness, patients with type 1 diabetes must continue insulin and often require additional insulin 3
• Test blood glucose and ketones (blood or urine), drink adequate fluids, and ingest 150-200 grams of carbohydrate daily (45-50 grams every 3-4 hours) 3
• If unable to tolerate regular food, use liquid or soft carbohydrate-containing foods (sugar-sweetened beverages, juices, soups, ice cream) 3
• Prompt consultation with healthcare provider if nausea, vomiting, or altered mental status prevents fluid and carbohydrate intake 3

Structured Discharge Communication

• Schedule outpatient follow-up appointment before discharge to enhance appointment-keeping behavior 3
• Transmit discharge summary to primary care provider as soon as possible after discharge 3
• Communicate medication changes, pending tests, and follow-up needs accurately and promptly 3
• Ensure prescriptions for new or changed medications are filled and reviewed with patient and family at or before discharge 3
• Provide adequate durable medical equipment, medications, supplies (glucose test strips), and prescriptions to avoid dangerous hiatus in care 3

Preventing Recurrence

• Diabetes education programs, improved follow-up care, and access to medical advice reduce DKA hospitalization frequency 6
• Early detection through patient education is critical, as the majority of DKA cases occur in patients with known diabetes and should be largely preventable 6
• Provide education on DKA recognition, prevention, and management 2

Monitoring Timeline Post-Discharge

• Follow-up within 1-2 weeks with primary care provider or endocrinologist 3
• Continue frequent home glucose monitoring (at least 4 times daily initially) 3
• If on antipsychotic medication, check fasting glucose within 1 week, then monthly for 3 months, then quarterly 7
• Reassess need for continued antipsychotic treatment periodically 7