Can a patient with isolated hyperglycemia (high blood sugar) and no severe symptoms or significant comorbidities be discharged from the Emergency Department (ED)?

Can a Patient with Isolated Hyperglycemia Be Discharged from the ED?

Yes, patients with isolated hyperglycemia can be safely discharged from the ED if they do not have diabetic ketoacidosis (DKA), hyperosmolar hyperglycemic state (HHS), or severe symptoms requiring admission, and if appropriate discharge planning with close follow-up is arranged. 1, 2

Key Discharge Criteria

What Constitutes "Isolated" Hyperglycemia Suitable for Discharge

• Exclude hyperglycemic emergencies first: The patient must NOT have DKA (glucose >250 mg/dL with ketones, acidosis pH <7.3, bicarbonate <15 mmol/L) or HHS (glucose >600 mg/dL, serum osmolality >320 mOsm/kg, altered mental status) 3, 4
• Clinical stability is mandatory: The patient must be hemodynamically stable, alert and oriented, able to eat and drink, and without severe symptoms requiring inpatient management 4, 5
• No acute precipitating illness requiring admission: Rule out serious infections (pneumonia, UTI, sepsis), acute coronary syndrome, or other conditions that would independently require hospitalization 3, 6

The Discharge Glucose Number Matters Less Than You Think

A critical finding: discharge glucose level itself is NOT associated with 7-day adverse outcomes in patients with moderate to severe hyperglycemia. 2 In a cohort of 422 patients discharged with mean arrival glucose of 491 mg/dL and discharge glucose of 334 mg/dL, the actual discharge glucose value did not predict repeat ED visits or hospitalization within 7 days 2. This challenges the traditional practice of aggressively lowering glucose before discharge.

• Practical implication: You do not need to achieve a specific glucose target (like <200 mg/dL) before discharge if the patient is otherwise stable and has appropriate follow-up 2
• Treatment in the ED: While 10 units of subcutaneous insulin reduces glucose by approximately 33 mg/dL and 1 liter of IV fluid by 27 mg/dL, IV fluids significantly increase ED length of stay by 45 minutes per liter without improving outcomes 7

Essential Discharge Requirements

Immediate Actions Before Discharge

• Check or obtain A1C if not done in previous 3 months: This helps determine if diabetes preceded the ED visit (A1C ≥6.5% suggests pre-existing diabetes) and guides discharge medication intensity 3
• Establish or confirm diabetes diagnosis: A random plasma glucose ≥200 mg/dL with symptoms of hyperglycemia establishes type 2 diabetes diagnosis in the ED per American Diabetes Association criteria 1
• Initiate or adjust medications:
  • If A1C <7-7.5%: Resume pre-admission regimen 4
  • If A1C 7-10%: Add basal insulin (e.g., 10 units glargine daily) or intensify oral agents 4, 1
  • If A1C >10%: Start basal-bolus insulin regimen at 0.3-0.5 units/kg/day 4
• NEVER discharge on sliding-scale insulin alone: This results in poor glycemic control and increased complications 3, 4

Critical Discharge Education (Survival Skills)

The patient must receive and demonstrate understanding of 3, 4:

• Hypoglycemia recognition and treatment: Symptoms (shakiness, sweating, confusion), treatment with 15g fast-acting carbohydrate, when to call 911 4, 8
• Home glucose monitoring: Check at least 4 times daily initially (fasting and before meals), target ranges (typically 80-130 mg/dL fasting, <180 mg/dL postprandial) 4, 8
• Medication administration: How and when to take insulin or oral agents, proper injection technique if applicable 3, 4
• Sick day rules: Continue diabetes medications, check glucose every 4 hours, maintain hydration, check temperature, when to return to ED 3

Mandatory Follow-up Arrangements

• Schedule follow-up within 1-2 weeks: With primary care provider, endocrinology, or diabetes educator 4, 8
• Provide prescriptions and supplies: Blood glucose meter, test strips, lancets, insulin/syringes if prescribed, and ensure patient can afford medications 3, 4
• Communicate with outpatient provider: Discharge summary should include glucose levels, new diagnosis or medication changes, and recommended ongoing treatment 4

Critical Pitfalls to Avoid

The Sentinel Visit Warning Sign

17% of patients presenting with hyperglycemic emergencies had an ED visit within the preceding 14 days, and 94% of those were discharged with either no glucose check or elevated glucose (>11.0 mmol/L). 6 Of these sentinel visits, 43% returned requiring admission for severe hyperglycemia, DKA, or HHS 6.

To prevent this:

• Always check blood glucose in diabetic patients presenting for ANY complaint 6
• If glucose is elevated (>200 mg/dL), provide explicit discharge instructions for glucose management and urgent follow-up even if the primary complaint is unrelated 6
• Consider the presenting complaint (infection is a common precipitant) and ensure adequate treatment 6

Patients Who Should NOT Be Discharged

• Persistent hyperglycemia >180 mg/dL in hospitalized context requires insulin therapy per guidelines, but this threshold applies to admitted patients, not ED discharge decisions 3
• Altered mental status, severe dehydration, or inability to take oral intake 4, 5
• Suspected DKA/HHS even if laboratory confirmation is pending 3, 4
• No reliable follow-up available or patient unable to perform self-care 3, 4
• Active infection requiring IV antibiotics or other acute illness requiring admission 3, 6

Special Populations

• Older adults (≥80 years): Five times more likely to be admitted for insulin-related hypoglycemia; consider oral agents instead of insulin when possible, and relax targets to A1C 8-8.5% if appropriate 3
• Patients with limited health literacy or language barriers: Ensure use of interpreters, simplified written instructions, and teach-back method to confirm understanding 3