By Dr. Janine Malcom and Dr. Ilana Halperin
Hyperglycemia is common in hospitalized people, even among those without a previous history of diabetes, and is associated with increased in-hospital complications, longer length of stay and mortality. Acute illness results in a number of physiological changes or therapeutic choices that can exacerbate hyperglycemia. Hyperglycemia, in turn, causes physiological changes that can exacerbate acute illness, such as decreased immune function. These lead to a complex cycle of worsening illness and poor glucose control. Although a growing body of literature supports the need for targeted glycemic control in the hospital setting, blood glucose (BG) is often poorly controlled and is frequently overlooked in general medicine and surgery services. This is likely because the majority of hospitalizations for patients with diabetes are not directly related to their metabolic state and diabetes management is rarely the primary focus of care. Therefore, glycemic control and other diabetes care issues may not specifically addressed.
How should diabetes be managed in hospital?
Glycemic targets for hospitalized people with diabetes are modestly higher than those generally advised for outpatients with diabetes as the hospital setting presents unique challenges for the management of hyperglycemia, such as variations in patient nutritional status and the presence of acute illness. For the majority of noncritically ill hospitalized people, recommended preprandial BG targets are 5.0 to 8.0 mmol/L, in conjunction with random BG values <10.0 mmol/L, as long as these targets can be safely achieved.
Insulin is the preferred treatment for hyperglycemia in hospitalized people with diabetes. A proactive approach to glycemic management using scheduled basal (long acting), bolus (fast acting) and correction (supplemental fast acting to correct high glucose levels) insulin is the preferred method. There is a growing body of evidence that shows supplemental insulin alone results in worse glycemic control and is associated with increased surgical complications.
Bolus insulin can be withheld or reduced in people who are not eating regularly; however, basal insulin should not be withheld. People with type 1 diabetes must be maintained on insulin therapy at all times to prevent DKA. Insulin is often required temporarily in hospital, even in people with type 2 diabetes not previously treated with insulin. In these insulin-naive people, there is evidence demonstrating the superiority of basal-bolus-correction insulin regimens.
What are safety issues to consider for diabetes management in hospital?
Insulin is considered a high-alert medication and can be associated with risk of harm and severe adverse events. A systems approach that includes pre-printed, approved, unambiguous standard orders for insulin administration and/or a computerized order entry system may help reduce errors in insulin ordering.
Hypoglycemia remains a major barrier to achieving optimal glycemic control in hospitalized people with diabetes. Standardized treatment protocols that address mild, moderate and severe hypoglycemia may help mitigate this risk. Education of healthcare workers about factors that increase the risk of hypoglycemia, such as sudden reduction in oral intake, discontinuation of parenteral or enteral nutrition, unexpected transfer from the nursing unit after rapid-acting insulin administration or a reduction in corticosteroid dose are important steps to reduce the risk of hypoglycemia.
What systems changes can improve glycemic control in hospital?
Order sets for basal-bolus-correction insulin regimens, insulin management algorithms, and computerized order entry systems have been shown to improve glycemic control and/or reduce adverse outcomes in hospitalized people with diabetes. Computerized and mobile decision support systems (that provide suggestions for insulin dosing) have also been used and have been associated with lower mean BG levels; hypoglycemia can be an unintended consequence of tighter glycemic control.
The timely consultation of glycemic management teams has also been found to improve the quality of care provided, reduce the length of hospital stay and lower costs, although differences in glycemic control were minimal. Deployment of nurses, nurse practitioners and physician assistants with specialty training has been associated with greater use of basal-bolus insulin therapy and lower mean BG levels.
Interventions that ensure continuity of care, such as arranging continuation of care after discharge, telephone follow up and communication with primary providers at discharge, have been associated with a post-discharge reduction in A1C. Providing people with diabetes and their family or caregivers with written and oral instructions regarding their diabetes management at the time of hospital discharge will facilitate transition to community care.
Where can I learn more?
The 2018 Diabetes Canada Clinical Practice Guidelines has a chapter specifically dedicated to inpatient management.
Example order sets, policies and patient education material can also be found here
Dr. Janine Malcolm MD FRCPC is an Endocrinologist at Sunnybrook Health Sciences Centre and Dr. Ilana Halperin is a Clinical investigator with the Department of Medicine, University of Ottawa and the Ottawa Health Research Institute Program Director for the University of Ottawa Fellowship program in Endocrinology and Metabolism.