What is the optimal plan of care for a patient with variable blood sugar levels, ranging from hypoglycemia to hyperglycemia, 3 weeks post-nephrectomy, currently on Farxiga (dapagliflozin) and Lantus (insulin glargine) 24 units in the morning?

Immediate Plan of Care for Post-Nephrectomy Patient with Glycemic Variability

Discontinue Farxiga immediately and reduce Lantus dose by 20% (to approximately 19 units), then implement a structured titration protocol with daily fasting glucose monitoring. This patient's severe glycemic variability post-surgery, combined with reduced renal function from nephrectomy, creates a dangerous situation requiring urgent medication adjustment.

Critical First Steps

Discontinue SGLT2 Inhibitor (Farxiga)

• Stop dapagliflozin (Farxiga) immediately due to altered renal function post-nephrectomy 1
• SGLT2 inhibitors cause osmotic diuresis and can worsen volume depletion in post-surgical patients, particularly those with reduced renal mass 1
• The FDA label specifically notes increased risk of volume depletion in patients with renal impairment (eGFR 30-60 mL/min/1.73 m²), and this patient now has only one kidney 1
• Risk of diabetic ketoacidosis is elevated in surgical/stress states, with 27 DKA events reported per 8,574 patients in trials 1

Adjust Basal Insulin Immediately

• Reduce Lantus from 24 units to approximately 19 units (20% reduction) given the hypoglycemic episodes and erratic eating post-surgery 2
• The American Diabetes Association recommends reducing insulin dose by 10-20% when hypoglycemia occurs without clear cause 2
• Never skip basal insulin entirely, even after nocturnal hypoglycemia—this leads to rebound hyperglycemia and dangerous glycemic variability 3, 4

Structured Titration Protocol

Daily Monitoring Requirements

• Check fasting blood glucose every morning before insulin administration 5
• Check blood glucose before each meal and at bedtime (minimum 4 times daily) 5
• Set fasting plasma glucose target of 100-130 mg/dL (less aggressive given recent surgery and hypoglycemia risk) 2, 5

Insulin Dose Adjustment Algorithm

• If fasting glucose 140-179 mg/dL: Increase Lantus by 2 units every 3 days 2, 5
• If fasting glucose ≥180 mg/dL: Increase Lantus by 4 units every 3 days 2, 5
• If fasting glucose <100 mg/dL or any glucose <70 mg/dL: Decrease Lantus by 2-4 units (10-20% reduction) 2
• If severe hypoglycemia (<54 mg/dL) occurs: Reduce dose by 20% and reassess in 24 hours 2

Managing Hypoglycemia Risk

Immediate Hypoglycemia Treatment

• For glucose <70 mg/dL with symptoms: Give 15-20g fast-acting carbohydrates orally 2
• For glucose <54 mg/dL: Treat immediately even without symptoms 2
• Recheck glucose in 15 minutes and retreat if still <70 mg/dL 2
• Prescribe glucagon emergency kit for severe hypoglycemia episodes 2

Common Pitfall to Avoid

• The patient's current practice of skipping Lantus entirely after nocturnal hypoglycemia is dangerous and explains the subsequent hyperglycemia to 250+ mg/dL 3, 4
• Basal insulin provides 24-hour background coverage; skipping doses causes metabolic instability 3, 4
• Instead, reduce the dose by 10-20% but continue daily administration 2

Addressing Post-Surgical Factors

Stress Hyperglycemia Considerations

• Post-surgical stress, pain, and altered eating patterns contribute to glycemic variability 2
• As recovery progresses over 4-6 weeks, insulin requirements typically stabilize 2
• Monitor for signs of infection or surgical complications that worsen hyperglycemia 2

Renal Function Monitoring

• Check serum creatinine and eGFR within 1 week to establish new baseline with single kidney 1
• SGLT2 inhibitors cause transient creatinine increases within 2 weeks of initiation, but this patient needs baseline renal function assessment first 1
• Insulin dosing may need adjustment based on new renal function 2

When to Add Prandial Insulin

Indications for Mealtime Coverage

• If fasting glucose reaches target (100-130 mg/dL) but post-meal glucose remains >180 mg/dL, add rapid-acting insulin with the largest meal 2
• Start with 4 units of rapid-acting insulin (lispro, aspart, or glulisine) before the meal causing greatest glucose excursion 2
• This is typically needed when basal insulin exceeds 0.5 units/kg/day (~35-40 units for average adult) 2

Signs of Overbasalization to Watch For

• Basal dose >0.5 units/kg/day with persistent hyperglycemia 2
• Large bedtime-to-morning glucose differential (≥50 mg/dL) 5
• Hypoglycemia between meals but high post-meal glucose 5

Follow-Up Timeline

Week 1-2 Post-Adjustment

• Daily phone contact or patient portal messaging to review glucose logs 5
• Adjust Lantus dose every 3 days based on fasting glucose pattern 2, 5
• Ensure patient understands hypoglycemia treatment and when to call 2

Week 3-4

• In-person or telehealth visit to assess overall glycemic control 2
• Check HbA1c if not done in past 3 months 2
• Reassess need for additional diabetes medications once surgical recovery stabilizes 2

Month 2-3

• Once glycemic stability achieved, consider reintroducing SGLT2 inhibitor only if renal function adequate (eGFR >30 mL/min/1.73 m²) and patient has cardiovascular disease or heart failure indication 6
• Alternative: Consider GLP-1 receptor agonist for additional glycemic control with weight loss benefit and low hypoglycemia risk 2

Patient Education Priorities

Critical Teaching Points

• Never skip basal insulin—reduce dose instead if concerned about hypoglycemia 3, 4
• Recognize hypoglycemia symptoms: shakiness, sweating, confusion, hunger 2
• Always carry fast-acting glucose source (glucose tablets, juice) 2
• Maintain consistent meal timing during recovery period 5
• Report any glucose <54 mg/dL or >300 mg/dL immediately 2

Sick Day Rules

• Continue basal insulin even if not eating well 4
• Check glucose every 4-6 hours during illness 4
• Check urine ketones if glucose >250 mg/dL 2
• Seek immediate care for persistent vomiting, confusion, or ketones 2