Diabetes Emergencies: When High Blood Sugar Becomes Life-Threatening

🔬 What is Hyperglycemic Crisis?

Hyperglycemic crisis refers to life-threatening complications of diabetes where blood sugar rises to dangerously high levels. According to the 2024 ADA Consensus Report, hospital admissions for these emergencies have increased considerably over the past decade.

Both conditions are medical emergencies requiring immediate hospitalization. However, HHS carries a significantly higher mortality risk and is often underrecognized.

Here's something that will change how you think about diabetes emergencies: Sunita's father survived - but only because his neighbor happened to be a nurse who recognized the signs. What she noticed in the first 30 seconds saved his life. We'll reveal exactly what she looked for in the Warning Signs section below.

Alarming Trends in Hospitalizations

Despite being largely preventable, hyperglycemic crises continue to rise:

• DKA hospitalizations increased from 80,000 to over 188,000 annually in the US (2009-2019)
• HHS hospitalizations rose from approximately 18,000 to 26,000 in the same period
• Healthcare costs exceed $5 billion annually for hyperglycemic emergencies
• Disparities disproportionately affect minorities and low-income populations

🚨 Understanding HHS (Hyperosmolar Hyperglycemic State)

HHS is the more deadly of the two hyperglycemic crises, yet it receives far less attention than DKA. According to NCBI StatPearls, HHS accounts for less than 1% of all diabetes-related hospitalizations but carries mortality rates of 5-20%.

What Makes HHS So Dangerous?

• Gradual onset: Develops over days to weeks, allowing severe dehydration to accumulate
• Extreme dehydration: Patients may lose 8-12 liters of fluid before seeking help
• Older population: Typically affects elderly with multiple comorbidities
• Neurological complications: Confusion, seizures, and coma are common
• Delayed recognition: Symptoms mimic stroke, dementia, or other conditions

HHS by the Numbers (2024 Data)

But here's what makes HHS particularly insidious: while DKA announces itself with dramatic symptoms like fruity breath and rapid breathing, HHS creeps up silently over days. By the time confusion sets in, patients have often lost 8-12 liters of fluid. The next section reveals why this difference matters for survival...

⚖️ DKA vs HHS: Critical Differences

Understanding the differences between DKA and HHS is essential for proper recognition and treatment. While they share some features, their pathophysiology, presentation, and management differ significantly.

The DKA-HHS Overlap Syndrome

Up to one-third of patients present with features of both DKA and HHS, creating a particularly dangerous situation. According to a 2025 narrative review, the DKA-HHS overlap phenotype carries:

• 8% mortality - higher than isolated DKA (3%) or HHS (5%)
• Increased risk of cerebral edema
• Higher rates of thromboembolism
• Greater likelihood of acute kidney injury

The most dangerous scenario? When someone shows features of both DKA AND HHS. But there's a specific window of time where intervention makes all the difference - and it's shorter than most people think...

⚠️ Warning Signs and Symptoms

Remember Sunita's neighbor - the nurse who saved her father's life? Here's exactly what she noticed in those first 30 seconds: His skin was dry and papery. His eyes were sunken. And when she asked him simple questions ("What day is it?"), his answers made no sense. These three signs - severe dehydration, sunken eyes, and altered mental status - screamed HHS to her trained eye.

Recognizing the warning signs early can be life-saving. Both DKA and HHS share some symptoms, but their onset and severity differ significantly.

Early Warning Signs (Act Now)

• Extreme thirst (polydipsia) - drinking unusual amounts of water
• Frequent urination (polyuria) - may progress to decreased urination as dehydration worsens
• Fatigue and weakness - progressive, not relieved by rest
• Blurred vision - can fluctuate with blood sugar levels
• Nausea and vomiting - accelerates dehydration
• Blood sugar consistently above 300 mg/dL - check ketones

Late/Severe Warning Signs (Emergency - Call 911)

📞 When to Call 911

Knowing when to seek emergency help can mean the difference between life and death. Do not hesitate - these conditions deteriorate rapidly.

What to Do While Waiting for Emergency Services

1. Stay calm and keep the person calm
2. Do NOT give insulin unless specifically instructed by emergency services
3. If conscious and can swallow safely, small sips of water may help
4. Position them safely - on their side if unconscious (recovery position)
5. Have their medications ready to show paramedics
6. Note the time symptoms started and any recent changes

🔍 Causes and Triggers

Understanding what triggers hyperglycemic emergencies helps with prevention. According to the Cleveland Clinic Journal of Medicine (2025), most cases have identifiable precipitating factors.

Common Triggers

1. Infection (Most Common - 40-79% of cases)

• Urinary tract infections - especially common in elderly
• Pneumonia - respiratory infections are major triggers
• Skin infections - including diabetic foot infections
• Sepsis - severe infection can rapidly precipitate crisis

Infection causes a rise in counterregulatory hormones and cytokines that worsen insulin resistance and glucose control.

2. Medication-Related Issues

• Missed insulin doses or inadequate insulin therapy
• Non-adherence to oral diabetes medications
• Medications that raise blood sugar:
  • Corticosteroids (prednisone, dexamethasone)
  • Thiazide diuretics
  • Beta-blockers (can mask symptoms)
  • Atypical antipsychotics

3. New-Onset Diabetes

Strikingly, 32% of HHS patients had no prior diabetes diagnosis according to the 2024 Danish study. The hyperglycemic crisis was their first indication of diabetes.

4. Other Medical Events

• Heart attack - stress response raises blood sugar
• Stroke - can both trigger and be caused by HHS
• Trauma or surgery - acute stress response
• Pancreatitis - affects insulin production

5. Lifestyle Factors

• Inadequate fluid intake - critical in HHS development
• Alcohol abuse - dehydration and impaired judgment
• Drug use - especially cocaine (raises blood sugar)
• Heat exposure - dehydration in hot weather

🏥 Hospital Treatment

Based on the 2024 ADA Consensus Report, treatment follows a structured protocol. HHS typically requires ICU admission due to higher mortality risk.

Treatment Priorities (In Order)

1. Fluid Replacement (First Priority)

• Initial rate: 500-1000 mL/hour for first 2-4 hours
• Goal: Restore perfusion and correct severe dehydration
• Type: Crystalloid solutions (normal saline or balanced crystalloids)
• HHS patients may need 8-12 liters total replacement

2. Electrolyte Monitoring and Replacement

• Potassium is critical: Must be >3.3 mEq/L before starting insulin
• Severe hypokalemia (≤2.5 mmol/L) associated with 3-fold increase in mortality
• Check potassium every 2 hours initially, then every 4 hours
• Sodium, phosphorus, and magnesium also monitored

3. Insulin Therapy

• DKA: Start IV insulin immediately (after confirming potassium level)
• HHS: Insulin used more cautiously - fluids first to avoid rapid osmolar shifts
• Goal: Reduce glucose by 50-75 mg/dL per hour
• Target glucose: 200 mg/dL for DKA, 300 mg/dL for HHS before switching to dextrose-containing fluids

4. Treat Underlying Cause

• Identify and treat infection (antibiotics if indicated)
• Address cardiac events, stroke, or other precipitants
• Review medications that may have contributed

Treatment Duration

• DKA resolution: Typically 12-24 hours with proper treatment
• HHS resolution: 1-3 days, often longer due to severity
• ICU stay: Variable, depends on complications and underlying conditions

🛡️ Prevention Strategies

Six months after her father's HHS emergency, Sunita has become something of a diabetes safety expert. She created a laminated card with warning signs that now hangs on their refrigerator. Her father hasn't had a single blood sugar reading above 250 mg/dL since. What changed?

According to the 2025 ADA Standards of Care, structured education on hyperglycemic crisis prevention should be provided to all individuals with Type 1 diabetes and those with Type 2 who have experienced these events or are at high risk. Here's what Sunita learned - and what you need to know:

Daily Prevention Measures

1. Take medications as prescribed
   • Never skip insulin doses
   • Don't stop medications without consulting your doctor
   • Keep emergency medication supplies
2. Monitor blood sugar regularly
   • More frequent testing during illness
   • Know your target ranges
   • Check ketones when blood sugar >300 mg/dL
3. Stay well-hydrated
   • Drink plenty of water (8-10 glasses daily)
   • Increase fluids during hot weather or illness
   • Avoid excessive caffeine and alcohol
4. Recognize early warning signs
   • Unusual thirst or frequent urination
   • Fatigue, blurred vision, nausea
   • Blood sugar consistently above 250 mg/dL

Sick Day Management Plan

Having a sick day plan is crucial. Discuss with your healthcare team:

Long-Term Prevention

• Regular check-ups: HbA1c every 3-6 months
• Diabetes education: Understand your condition and treatment
• Medical ID: Wear a medical alert bracelet or necklace
• Emergency contacts: Ensure family/caregivers know the signs
• Consistent routine: Regular meals, medication times, and sleep schedule

👥 Special Populations at Risk

Elderly Adults

The median age for HHS is 69 years. Older adults face unique risks:

• Impaired thirst mechanism: May not feel thirsty despite dehydration
• Reduced kidney function: Can't conserve water as effectively
• Multiple medications: Drug interactions can raise blood sugar
• Cognitive changes: May not recognize or report symptoms
• Living alone: No one to notice early warning signs

People with Cognitive Impairment

• Cannot reliably self-monitor or take medications
• May not communicate symptoms
• Caregivers must be trained in recognition and response

Those on SGLT2 Inhibitors

The 2024 ADA report highlights euglycemic DKA risk:

• DKA can occur with near-normal blood sugar (<250 mg/dL)
• May delay diagnosis - always check ketones if symptomatic
• New diagnostic criteria now include "history of diabetes" to catch these cases

Newly Diagnosed Patients

• 32% of HHS patients had no prior diabetes diagnosis
• First presentation of diabetes may be a crisis
• Important to recognize symptoms in those with risk factors (obesity, family history)

❓ Frequently Asked Questions

Last Reviewed: January 19, 2026