Hyperglycemia – when does it become an emergency?   


Melissa Kalensky, DNP, FNP-BC, PMHNP-BC, CNE

In the United States, approximately 34 million individuals have diabetes, with prediabetes impacting an estimated 88 million more1. At an annual cost of $327 billion, care related to diabetes accounts for one out of every four dollars spent on health care costs within the US2. The added strain placed on our nation’s health system throughout the COVID-19 pandemic has often resulted in patients delaying care, presenting at later disease stages, and requiring intervention for acute complications of conditions such as diabetes.      

Considerations for Emergency Management   

Diabetic ketoacidosis (DKA) is perhaps the most well recognized acute complication related to hyperglycemia. However, clinicians should also learn to recognize hyperglycemic hyperosmolar state (HHS) given the relatively high associated mortality rate; 1-5% versus 20-50% respectively 3-5. Both DKS and HHS can occur with type 1 or type 2 diabetes; however, DKA is more common in type 1 diabetes (accounting for two-thirds of hospital presentations), and 90% of patients presenting with HHS have a diagnosis of type 2 diabetes3. Typically described as distinct conditions, clinicians should be aware that nearly one-third of patients may present with findings of both4.   

Initial Evaluation of Hyperglycemia   

In patients presenting to the office with complaints of and symptoms potentially related to hyperglycemia, initial evaluation should include a detailed history, physical exam, blood glucose level, and urine or serum ketones measurement. The initial account should seek to identify symptoms related to the current presentation and investigate the potential underlying cause of hyperglycemia. Both conditions commonly include polyuria, polydipsia, and weight loss at initial onset3-5. Rapid progression of symptoms is the hallmark of DKA, with deterioration in less than 24hrs, while HHS has a more insidious onset of days to weeks6. Other presenting symptoms with DKA include fatigue, dyspnea, nausea, vomiting, and abdominal pain5-6. Neurologic symptoms such as lethargy, focal neurologic deficits, hemiparesis, seizures, and coma are more indicative of HHS4, 6. Two critical differences in point of care testing include blood glucose level and the presence of ketones. Blood glucose levels in DKA are moderately elevated >250mg/dl (typically ranging from 200-500), with ketones present in the urine. HHS’s blood glucose levels are more markedly elevated, >600mg/dl (frequently > 1,000 mg/dl) with minimal or no ketones present in the urine6.    

  • New-onset (or undiagnosed) diabetes. 
  • Medication non-adherence. 
  • Side effects of prescription drugs (e.g., corticosteroids, antipsychotics, diuretics, methadone, etc.). 
  • The use of alcohol or drugs such as cocaine4-6

The pathology that may create secondary hyperglycemia includes but is not limited to infection (e.g., pneumonia UTI, cellulitis, etc.), thyroid disease, venous thrombosis, myocardial infarction, cerebral vascular accident, and renal failure4, 5.      

With acute changes in blood glucose clinical findings, the clinician’s ability to evaluate expediently will dictate the required level of care. Chronic hyperglycemia ongoing evaluation and management of blood glucose to ensure that patients know how and when to seek emergency care if complications come about. Individuals who are asymptomatic at presentation and have an easily identified source of hyperglycemia may be a candidate for outpatient management. Clinical risk factors, such as age, frailty, medical comorbidities, and current medications, may impact treatment decision-making. In particular, advanced age increases the risk for underlying primary medical pathology and often complicates differential diagnosis. However, regardless of comorbidity, emergent referral for ED evaluation is required with any changes in mental status, unstable vital signs, physical exam findings suggestive of dehydration, or elevated blood glucose coupled with ketones in the urine. In addition, if your evaluation includes DKA or HHS as part of a differential diagnosis, referral to emergency medicine is warranted. Both conditions will require inpatient management, ongoing insulin administration, intravenous fluid resuscitation, and addressing precipitating medical conditions is needed regardless of the hyperglycemic complication. 

See Melissa Kalensky speak at a 2022 Skin, Bones, Hearts & Private Parts CME Conference. Click here to find out where you can see her live and in-person!


  1. Diabetes data and statistics. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/data/index.html. Published June 15, 2021. Accessed February 6, 2022.  
  1. Cost-effectiveness of diabetes interventions. Centers for Disease Control and Prevention. https://www.cdc.gov/chronicdisease/programs-impact/pop/diabetes.htm. Published May 17, 2021. Accessed February 6, 2022.  
  1. Gosmanov AR, Gosmanova EO, Kitabchi AE. Hyperglycemic Crises: Diabetic Ketoacidosis and Hyperglycemic Hyperosmolar State. [Updated 2021 May 9]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279052/ 
  1. Stoner GD. Hyperosmolar Hyperglycemic State. Am Fam Physician. 2017 Dec 1;96(11):729-736. PMID: 29431405. 
  1. Westerberg DP. Diabetic ketoacidosis: evaluation and treatment. Am Fam Physician. 2013 Mar 1;87(5):337-46. PMID: 23547550. 
  1. Hirsch, IB, Emmett, M. (2020). Diabetic ketoacidosis and hyperosmolar hyperglycemic state in adults: Clinical features, evaluation, and diagnosis. In: Nathan, DM, ed. UpToDate; 2020. Accessed February 6, 2022. https://www.uptodate.com/contents/diabetic-ketoacidosis-and-hyperosmolar-hyperglycemic-state-in-adults-clinical-features-evaluation-and-diagnosis?search=hhs&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H9 
  2. Hirsch, IB, Emmett, M. (2020). Diabetic ketoacidosis and hyperosmolar hyperglycemic state in adults: Clinical features, evaluation, and diagnosis. In: Nathan, DM, ed. UpToDate; 2020. Accessed February 6, 2022. https://www.uptodate.com/contents/diabetic-ketoacidosis-and-hyperosmolar-hyperglycemic-state-in-adults-clinical-features-evaluation-and-diagnosis?search=hhs&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H9