a dynamic fashion.
Changing patient circumstances also drive modifications to insulin regimens in the hospital. These include transitions from ICU to noncritical care settings, which call for changes from IV infusion to SQ injections of insulin; nutrition therapy transitions between enteral or parenteral therapy and solid foods; or perioperative glycemic control. Patients admitted for diabetic hyperglycemic crises (diabetes ketoacidosis or hyperglycemic hyperosmolar state) also will require insulin therapy along with close monitoring of blood glucose values to reduce the risk of hypoglycemia. Of course, these patients also require extensive management decisions related to fluids and electrolytes, beyond mere glycemic control.
Monitoring the patient’s glycemic status falls to point-of-care (POC) capillary blood glucose meters, which provide nearly instantaneous results and have become the standard measurement technique at the hospital bedside. Caution is required in interpreting the results from POC meters in patients who have anemia, polycythemia, or hypoperfusion or who use certain medications. Newer technologies, including continuous glucose monitoring, are under study.
Ongoing education of hospital personnel in these protocols is essential not only to ensure proper implementation but also to gain support of those involved in the care of inpatients with hyperglycemia, including the hospital administration. Evidence supporting the cost-effectiveness of a rational systems approach to inpatient glycemic management will help persuade administrators to provide necessary financial and operational support.27,28
Status of Glycemic Control in the Hospital Setting
The health-care community at large now generally accepts that both hyperglycemia and hypoglycemia are markers of poor clinical outcomes, and many institutions have made important strides to improve glycemia at their facilities. Multiple barriers persist, however, and the frequency of poor glycemic control remains high. In an analysis of a database containing information on 70,000 admissions of patients with diabetes, an HbA1c was recorded for only 18% of cases.29 The authors of this study found that, when A1C was measured, a value >8% prompted a change in antihyperglycemic regimen for only two-thirds of patients (64%). Additionally, several studies have documented failures to reliably follow hypoglycemia management protocols, with long delays in glucose retesting after hypoglycemic events, poor documentation of the hypoglycemic and subsequent treatment, and long intervals before hypoglycemia resolution.30–32 The root of the problem may be in poor communication and coordination between health-care teams,30,33 but knowledge gaps also appear to contribute. In a recent survey of health-care professionals working in an urban, community teaching hospital, only about half of questions regarding best practices for managing inpatient hyperglycemia were answered correctly by physicians, nurses, and dietitians (mean scores of 53%, 52%, and 48%, respectively). Pharmacists performed somewhat better (mean score 64%), whereas patient care assistants correctly answered only about a third of the questions (38%). In general, this group of health-care workers acknowledged the importance of controlling hyperglycemia, but they still preferred the perceived convenience of sliding-scale insulin, and this preference influenced clinical decision making.34
Many institutions rely on a systematic analysis of their glucose measurements to address these problems. Sometimes referred to as “glucometrics,” this approach incorporates the tracking of glycemic exposure, the efficacy of glycemic control, and the rates of adverse events and allows hospitals to measure the success of inpatient glucose management efforts. Individual health-care professionals can use glucometrics to identify and address the causes of hyper- and hypoglycemia. Institutions can use these metrics to identify opportunities for improvement in glycemic management across the health system. A goal of 85% of blood glucose levels within the target range has been proposed as a gold standard, and some groups recommend use of the patient-day unit of measure, because it may more accurately reflect the frequency of hypoglycemia and severe hyperglycemic events. Glucometric approaches have not been standardized, however, and various methods continue to be implemented. Of course, merely tracking glycemic values does not appear to improve outcomes.35 The data obtained must be used to guide the actions of health-care professionals across disciplines10,11,36 and to advise institutions to make strategic decisions regarding support staff, protocol development, and practitioner education.
Emerging Evidence to Control Glucose in the Inpatient Setting
Recent interest has focused on the potential of incretin-based therapies as a supplement or alternative to insulin therapy in the hospital setting. These agents carry a low risk of hypoglycemia and may offer cardioprotective benefits.37 One pilot study involving 90 patients randomly assigned general medical and surgery patients with type 2 diabetes to glucose management with the dipeptidyl peptidase 4 (DPP-4) inhibitor sitagliptin alone, sitagliptin plus insulin glargine, or a basal-bolus insulin regimen. Overall, the three treatment groups experienced similar glycemic control, although basal-bolus insulin provided better control in patients whose admission glucose was >180 mg/dL.38 In addition, patients in the sitagliptin-only group required correction doses with rapid-acting insulin as often as patients in the other groups to maintain target glucose levels. Rates of hypoglycemia were also similar among the three groups.
Glucagon-like peptide 1 (GLP-1) receptor agonists for inpatient management have shown some potential to control glucocorticoid-induced and stress hyperglycemia in several small studies, but so far no randomized, controlled trials have been conducted.37 In one pilot study involving 40 patients in a cardiac ICU, exenatide infusion successfully maintained a steady-state glucose value of 132 mg/dL without incidence of hypoglycemia; however, a large proportion of patients experienced nausea.39
Areas for future research include investigations of the following:
1. Glycemic quality measures needed to improve patient outcomes
2. Safe and effective methods of point-of-care testing for the management of glycemia in critically ill patients
3. The role of continuous glucose monitoring in the inpatient setting
4. Appropriate glycemic targets for different patient populations in the hospital setting
5. Efficacy and safety of incretin-based therapies in the management of hyperglycemia in the hospital setting
Conclusion
Management of glycemic control in the hospital setting continues to evolve. We have witnessed several shifts in treatment paradigms over the past two decades, from essentially ignoring blood glucose levels except for extremes, to overly stringent approaches stemming from initial clinical trials that reported benefits from achieving euglycemia, to a more rational approach over the past several years. Professional organizations and leading experts now advise controlling glucose, especially in the ICU, within the high-normal to mildly elevated range, while avoiding hypoglycemia. The overriding primary goal of treating hyperglycemia among hospital inpatients is now patient safety, because overtreatment and undertreatment of hyperglycemia are associated with adverse outcomes. Any validated protocols for the management of hyperglycemia should include provisions for glucose monitoring and the treatment of hypoglycemia as well as guidance on dynamically matching insulin doses to glucose levels. Smooth transitioning between IV and SQ insulin regimens is also important. Discharge planning, which should begin at hospital admission, is equally vital. A clear plan for outpatient glucose management, including transition to previous antihyperglycemic therapy before discharge, patient education about diabetes self-management, and clear communication with outpatient providers, will ensure a safe and successful transition to the outpatient arena. Developing reliable diabetes management systems in our hospitals, developed and tracked by a multidisciplinary group of key stakeholders, will ensure best practice in each of these domains.
References
1. Van den Berghe G, Wouters P, Weekers F, Verwaest C, Bruyninckx
