When should a patient with hyperketonemia and hyperglycemia be sent to the Emergency Room (ER)?

When to Send a Patient to the Emergency Room for High Ketones

Patients with elevated ketones should be sent to the ER immediately if they cannot tolerate oral hydration, have altered mental status, show signs of worsening illness, or fail to improve blood glucose with insulin administration. 1

Criteria for Home Management vs. ER Referral

Patients Who Can Be Managed at Home (Mild DKA)

Patients may attempt home management only when ALL of the following conditions are met: 1

• Hemodynamically stable (normal blood pressure and heart rate)
• Cognitively intact (alert and oriented)
• Able to tolerate oral hydration without vomiting
• Able to self-administer subcutaneous insulin
• Glucose levels are responding to insulin administration (decreasing by 50-75 mg/dL per hour)

These patients require frequent monitoring with blood glucose and ketone checks, noncaloric hydration, and subcutaneous insulin administration. 1

Absolute Indications for Immediate ER Referral

Send patients to the ER immediately if any of the following are present: 1, 2

• Unable to tolerate oral hydration or persistent vomiting 1, 2
• Altered mental status or confusion 1
• Blood glucose levels not improving with insulin administration 1
• Any signs of worsening illness (increasing lethargy, worsening abdominal pain, respiratory distress) 1
• Suspected hyperosmolar hyperglycemic state (HHS) - these patients require immediate inpatient evaluation due to severe volume depletion 1

Special High-Risk Populations Requiring Lower Threshold for ER Referral

Pregnant Patients

Any pregnant patient with concern for DKA should seek immediate medical attention due to significant risk of feto-maternal harm. 1 Pregnant individuals may present with euglycemic DKA (glucose <200 mg/dL), making diagnosis more challenging. 1

Patients on SGLT2 Inhibitors

These patients can develop euglycemic DKA with normal or near-normal glucose levels (sometimes <200 mg/dL). 1, 3 The presence of ketones with symptoms should prompt ER referral even if glucose appears reassuring. 3

Pediatric Patients

Children have higher risk of cerebral edema as a complication of DKA. 1 Any child with suspected DKA should be evaluated in the ER for close monitoring during fluid resuscitation. 1

Clinical Presentation Warranting ER Evaluation

DKA Warning Signs

DKA typically develops over hours to days and presents with: 1

• Nausea, vomiting, and abdominal pain 1
• Kussmaul respirations (deep, rapid breathing) 1
• Polyuria, polydipsia, weight loss, and dehydration 1
• Fruity odor on breath (from acetone) 4, 5
• Patients are usually alert initially 1

HHS Warning Signs

HHS develops more slowly over days to a week and presents with: 1

• Change in cognitive state is common 1
• Often copresenting with other acute illness 1
• Severe dehydration 1

Critical Pitfall to Avoid

Never discontinue insulin during illness, even if the patient is not eating. 1, 2, 4 This is the most common error that precipitates DKA and represents a medical emergency. 2 Patients should continue basal insulin and contact their diabetes care team for dose adjustments. 1

When to Check Ketones

Patients at risk for ketosis should measure urine or blood ketones when: 1

• Glucose levels exceed 200 mg/dL 1
• Symptoms of illness are present (nausea, vomiting, abdominal pain) 1
• Missed insulin doses 1
• Unexplained hyperglycemia 1

Blood ketone testing is preferred over urine testing as it provides more accurate real-time assessment and improves patient compliance with monitoring. 1