Introduction: Glycemic management in the intensive care unit is an evolving practice area. This evolution has included the refinement of blood glucose targets, matching glycemic management to premorbid status, and investigations into the impact of glycemic variability and relative hypoglycemia on ICU outcomes. The interplay between these phenomena and absolute hypoglycemia has yet to be investigated in hyperglycemic emergencies. Objectives: To examine the incidence of and risk factors for relative hypoglycemia and absolute hypoglycemia in patients admitted to an intensive care unit for the management of hyperglycemic emergencies. Methods: This was a retrospective, single-center, exploratory analysis of adults admitted to the medical intensive care unit for diabetic ketoacidosis or hyperosmolar hyperglycemic syndrome. The primary outcome was the incidence of relative hypoglycemia, defined as a blood glucose level 30% lower than baseline. The baseline was determined by the estimated average blood glucose calculated from hemoglobin A1c within 3 months of index admission. Secondary outcomes were ICU length of stay, glycemic variability, and incidence of absolute hypoglycemia.Results: Relative hypoglycemia was observed in 60% of patients in the cohort. Longer insulin infusion duration and higher hemoglobin A1c levels were found to statistically increase the risk of developing relative hypoglycemia. Higher glycemic variability and longer ICU length of stay were associated with the risk of developing absolute hypoglycemia. Conclusions: Relative hypoglycemia is a frequent occurrence in this patient population. Hemoglobin A1c and duration of the insulin infusion statistically influenced the risk of developing relative hypoglycemia. Higher glycemic variability and longer ICU stay were significantly associated with developing absolute hypoglycemia. While relative hypoglycemia is common in hyperglycemic emergencies, the clinical impact remains uncertain and warrants additional investigation.