In the medical intensive care unit, a patient who had sustained a cardiac arrest with return of spontaneous circulation but no recovery of neurological function develops septic shock complicated by end-stage renal disease, shock liver, and now refractory hypoglycemia.
An approximately 60 year-old male with diabetes is brought in by ambulance after family called 911 for unresponsiveness. His initial glucose was 35mg/dL, his home medications are unknown.
- Autonomic: tremor, palpitations, anxiety, diaphoresis
- Neuroglycopenic: cognitive impairment, psychomotor, seizure, coma
- Serum glucose <60mg/dL
- Generally symptomatic at <55mg/dL though threshold is variable depending on chronicity
- Whipple Triad:
- Symptoms suggestive of hypoglycemia
- Low glucose
- Resolution of symptoms after administration of glucose
Differential Diagnosis of Hypoglycemia
Common Anti-hyperglycemic Drugs and Pharmacology
Evaluation of Hypoglycemia
Patients with known diabetes who are not systemically ill and can identify a clear precipitant, no extensive workup is required. In severely ill patients, consider:
- Infectious workup: CXR, UA, urine and blood cultures
- ECG, troponin
- Other studies: insulin, C-peptide, pro-insulin, glucagon, growth hormone, cortisol, B-OH, insulin antibodies
Management and Monitoring
Admission or observation for oral anti-hyperglycemic agent or intermediate- to long-acting insulin. Consider discharge after 4h uneventful observation if:
- Hypoglycemia fully and rapidly reversed without continuous infusion of dextrose
- Tolerated a full meal in ED
- Clear and innocuous cause identified with recurrence unlikely
- Adequate patient understanding, home support/monitoring, and ability to detect/prevent recurrence with close primary care follow-up
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- Service FJ. Hypoglycemic disorders. N Engl J Med. 1995;332(17):1144–1152. doi:10.1056/NEJM199504273321707.
- Krinsley JS, Grover A. Severe hypoglycemia in critically ill patients: risk factors and outcomes. Critical Care Medicine. 2007;35(10):2262–2267. doi:10.1097/01.CCM.0000282073.98414.4B.
- Lacherade J-C, Jacqueminet S, Preiser J-C. An overview of hypoglycemia in the critically ill. J Diabetes Sci Technol. 2009;3(6):1242–1249.