Hyperglycemia and Diabetes in the Posttransplant Patient

Glycemic control can be challenging in posttransplant patients due to complex interplay of end-organ failure, variable insulin resistance, release of counterregulatory hormones, postoperative pain, and the use various immunosuppressive agents, all of which directly interfere with blood glucose metabolism. The result is usually highly fluctuating glucose levels which often result in acute hyperglycemia with a high risk of potential hypoglycemia as well. It is important to manage optimal glucose levels postoperatively as studies have linked glycemic control in posttransplant recipients with improved graft outcomes, lower risk of infections, and in some cases lower mortality. However, guidelines specifically addressing glucose target management in posttransplant patients are lacking with most of the evidence extrapolated from studies of nontransplant postoperative surgical patients. Early in the hospital course, insulin regimens, both intravenous and subcutaneous, may be the only appropriate option due to the rapidly changing clinical course of posttransplant patients. Non-insulin glucose-lowering agents may be appropriate in limited situations, with DPP4-inhibitors having the most evidence in the posttransplant setting. However, at present, there is a paucity of evidence and limitations to using other glucose-lowering agents, such as GLP1-RA and SGLT2-inhibitors.