Insulin therapy by either subcutaneous injection or intravenous insulin infusion should be started if there is persistent hyperglycemia postoperatively (>250 mg/dL [>14 mmol/L]) [158] that does not respond to fluid therapy or if there is hyperglycemia with hyperketonemia (beta-hydroxybutyrate levels >2 mmol/L). The gene discussed is INS; the disease is Hyperglycemia.