What is considered emergent hyperglycemia (high blood sugar)?

Emergent Hyperglycemia: Definition and Management

Blood glucose levels ≥ 250 mg/dL (13.9 mmol/L) with symptoms of hyperglycemic crisis, or ≥ 500 mg/dL (27.8 mmol/L) regardless of symptoms, constitute emergent hyperglycemia requiring immediate medical attention. 1

Clinical Presentations of Hyperglycemic Emergencies

Diabetic Ketoacidosis (DKA)

• Develops over hours to days, usually in patients with type 1 diabetes or absolute insulin deficiency 2
• Characterized by blood glucose typically >250 mg/dL (13.9 mmol/L), ketosis, and metabolic acidosis 2
• Clinical symptoms include polyuria, polydipsia, weight loss, dehydration, nausea, vomiting, abdominal pain, and Kussmaul respiration 2
• Patients are usually alert, though altered mental status can occur in severe cases 2

Hyperglycemic Hyperosmolar State (HHS)

• Develops more slowly, over days to a week 2
• Characterized by profound hyperglycemia (often >600 mg/dL or 33.3 mmol/L), hyperosmolarity, and severe dehydration without significant ketosis 3
• Change in cognitive state is common 2
• Often presents with concurrent acute illness 2
• More common in elderly patients with type 2 diabetes 3

Hybrid Presentation

• One-third of hyperglycemic emergencies present with features of both DKA and HHS 2

Risk Factors for Hyperglycemic Crises

• Type 1 diabetes/absolute insulin deficiency 2
• Younger age 2
• Prior history of hyperglycemic or hypoglycemic crises 2
• Presence of other diabetes complications 2
• Comorbid chronic health conditions 2
• Behavioral health conditions (depression, bipolar disorder, eating disorders) 2
• Alcohol and/or substance use 2
• High A1C level 2
• Social determinants of health 2
• Missed insulin doses or inadequate insulin therapy 4
• Infection or illness 4
• Significant stressful situations 4

Diagnostic Criteria for Emergent Hyperglycemia

• Random plasma glucose ≥200 mg/dL (11.1 mmol/L) with classic symptoms of hyperglycemia or hyperglycemic crisis 2
• Blood glucose >250 mg/dL (13.9 mmol/L) with ketones present indicates potential DKA 2
• Blood glucose persistently >20 mmol/L (360 mg/dL) or reading "HI" on glucometer suggests HHS 2
• Presence of ketones in blood (>2 mmol/L) or urine with hyperglycemia suggests DKA 2

When to Seek Emergency Medical Attention

Patients should seek immediate medical attention when:

• Blood glucose exceeds 250 mg/dL (13.9 mmol/L) with symptoms of DKA 2
• Blood glucose exceeds 500 mg/dL (27.8 mmol/L) even without symptoms 1
• Unable to tolerate oral hydration 2
• Blood glucose levels do not improve with insulin administration 2
• Altered mental status is present 2
• Signs of worsening illness occur 2
• Presence of ketones with blood glucose >200 mg/dL (11.1 mmol/L) 2
• Hypotension with hyperglycemia (indicates severe volume depletion) 1

Emergency Management

• Immediate vital signs monitoring including blood pressure, heart rate, respiratory rate, temperature, and oxygen saturation 1
• Laboratory evaluation including complete blood count, comprehensive metabolic panel, serum ketones, arterial blood gas, and urinalysis 1
• Begin immediate IV fluid resuscitation with isotonic saline to address dehydration and hypotension 1
• Adults with DKA typically require an average of 9 L of 0.9% saline over 48 hours 3
• After establishing urine output, begin potassium replacement 3
• Administer insulin therapy: initial bolus of 0.1 units/kg IV followed by continuous infusion of 0.1 units/kg/hour until blood glucose decreases below 300 mg/dL 3
• Add dextrose to IV fluids when blood glucose falls below 200-250 mg/dL (11.1-13.9 mmol/L) while continuing insulin to clear ketones 1
• In children and adolescents, correct dehydration at a rate of no more than 3 mOsm per hour to avoid cerebral edema 3

Prevention of Hyperglycemic Emergencies

• Regular blood glucose monitoring, especially during illness 2
• Measurement of urine or blood ketones when glucose levels exceed 200 mg/dL (11.1 mmol/L) during illness or with missed insulin doses 2
• Access to continuous glucose monitoring may decrease risk of DKA recurrence 2
• Readily available clinical support can help individuals self-manage hyperglycemia during illness and prevent emergency department visits 2
• Education about proper insulin administration and recognition of hyperglycemic symptoms 1

Common Pitfalls to Avoid

• Do not delay fluid resuscitation in a hypotensive patient with hyperglycemia 1
• Do not underestimate the severity of the condition even if the patient appears clinically stable 1
• Do not ignore hyperglycemia in the context of an acute illness, as this can rapidly progress to DKA or HHS 4
• Do not forget to monitor and replace electrolytes, particularly potassium, during treatment 1
• Do not stop insulin infusion prematurely, as ketosis may persist even after blood glucose normalizes 3