What is the best course of action for a 70-year-old female patient with type 2 diabetes mellitus (T2DM) and multiple chronic comorbidities, presenting with new-onset polyuria, significant glucosuria, mild ketosis, and somnolence?

Management of Hyperglycemia with Glucosuria and Somnolence in Type 2 Diabetes

This patient requires immediate insulin therapy initiation along with metformin, given the significant glucosuria (3+), trace ketones, and concerning somnolence suggesting metabolic decompensation from uncontrolled hyperglycemia. 1, 2

Immediate Assessment Required

Check fingerstick blood glucose immediately to quantify the degree of hyperglycemia, as urinalysis findings (3+ glucose, trace ketones) indicate significant hyperglycemia likely >250 mg/dL. 3, 1

Critical Laboratory Workup

• Obtain serum ketones (beta-hydroxybutyrate preferred) or blood ketone measurement to differentiate between simple hyperglycemia versus early diabetic ketoacidosis (DKA), as trace urine ketones warrant further evaluation. 3, 2
• Complete metabolic panel to assess for electrolyte abnormalities (particularly potassium), renal function (given CKD stage 2), and calculate anion gap. 2, 4
• Arterial blood gas if mental status continues to decline or if serum ketones are significantly elevated, to rule out metabolic acidosis. 2, 4

Common pitfall: Assuming trace ketones are benign—in elderly patients with altered mental status and poor oral intake, even trace ketones can progress to DKA, particularly with osmotic diuresis causing dehydration. 3, 5

Treatment Algorithm Based on Blood Glucose

If Blood Glucose ≥250 mg/dL (Most Likely Scenario)

Start basal insulin immediately at 0.5 units/kg/day subcutaneously while simultaneously initiating metformin 500 mg twice daily with meals (if eGFR >45 mL/min/1.73 m², which should be confirmed given her CKD stage 2). 1, 2

• Target glucose range of 140-180 mg/dL for this hospitalized/nursing facility patient with multiple comorbidities. 3, 1
• Monitor fingerstick glucose every 4-6 hours initially, then before meals and bedtime once stable. 3, 1
• Adjust insulin dose every 2-3 days by 10-20% based on fasting glucose trends. 1

If Blood Glucose >500 mg/dL or Signs of DKA/HHS

Transfer to emergency department for intravenous insulin infusion if blood glucose is severely elevated (>500 mg/dL), serum ketones are significantly elevated, anion gap >12, or mental status deteriorates further. 2, 6

• Continuous IV insulin infusion is the standard of care for critically ill patients or those with DKA/HHS. 3, 2
• Aggressive fluid resuscitation with 0.9% normal saline to restore circulating volume and correct dehydration from osmotic diuresis. 2, 6, 5

Addressing the Somnolence

The somnolence is likely multifactorial from hyperglycemia-induced osmotic diuresis causing dehydration, plus direct CNS effects of hyperglycemia. 3

• Hold all sedating PRN medications immediately (review medication list for benzodiazepines, opioids, antihistamines). 3
• Encourage oral fluid intake aggressively (at least 1.5-2 L over 24 hours if able to drink safely) to counteract dehydration from polyuria. 3, 1
• Monitor mental status every 4 hours—worsening confusion, lethargy, or inability to arouse warrants immediate transfer to acute care. 3

Critical caveat: In elderly patients with cerebrovascular disease history, rapid correction of severe hyperglycemia can paradoxically worsen mental status due to osmotic shifts. However, the greater risk here is progression to hyperosmolar hyperglycemic state (HHS), which carries 10-20% mortality. 6, 5

Fluid Management Strategy

Provide 1.5-2 L oral fluids over 24 hours if patient can drink safely without aspiration risk (assess swallow function given somnolence). 3, 1

• Monitor intake/output closely and daily weights as already planned. 3
• Assess for clinical dehydration: dry mucous membranes (already noted as moist, which is reassuring), skin turgor, orthostatic vital signs if patient can stand safely. 3
• If unable to maintain adequate oral intake, consider IV fluid bolus of 500 mL 0.9% normal saline over 1-2 hours, then reassess. 2, 6

Monitoring for Complications

Hypokalemia Risk

Check serum potassium before starting insulin and monitor every 12-24 hours initially, as insulin drives potassium intracellularly and can precipitate life-threatening hypokalemia. 3, 7

• If potassium <3.3 mEq/L, hold insulin and replace potassium first. 2, 5
• If potassium 3.3-5.0 mEq/L, add 20-40 mEq potassium to IV fluids or provide oral supplementation. 5

Renal Function Monitoring

Given CKD stage 2, avoid nephrotoxic agents and monitor creatinine closely with any volume shifts or medication changes. 3

• Metformin is safe if eGFR >45 mL/min/1.73 m² but should be held if eGFR drops below this threshold or if patient develops acute kidney injury. 1

Insulin Tapering Plan (Once Glucose Controlled)

Once glucose targets (140-180 mg/dL) are consistently met for 48-72 hours, taper insulin by 10-30% every few days over 2-6 weeks while continuing metformin. 1, 2

• If glycemic control is not maintained on metformin alone after insulin taper, consider adding a GLP-1 receptor agonist before reintroducing insulin long-term. 1

Follow-Up Timing

Reassess within 24-48 hours to review glucose trends, mental status improvement, and laboratory results. 2

• If no improvement in somnolence within 48 hours despite glucose normalization, consider alternative causes (medication effect, cerebrovascular event, infection despite negative urinalysis). 3
• Schedule outpatient endocrinology follow-up within 2-4 weeks after acute episode resolves to optimize long-term diabetes management. 2