In-Hospital Management of Diabetes.

Abstract

Key Messages•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.•Insulin is the most appropriate pharmacologic agent for effectively controlling glycemia in hospital. A proactive approach to glycemic management using scheduled basal, bolus and correction (supplemental) insulin is the preferred method. The use of correction-only (supplemental) insulin, which treats hyperglycemia only after it has occurred, should be discouraged as the sole modality for treating elevated blood glucose levels.•For the majority of noncritically ill hospitalized people with diabetes, preprandial blood glucose targets should be 5.0 to 8.0 mmol/L, in conjunction with random blood glucose values <10.0 mmol/L, as long as these targets can be safely achieved. For critically ill hospitalized people with diabetes, blood glucose levels should be maintained between 6.0 and 10.0 mmol/L.•Hypoglycemia is a major barrier to achieving targeted glycemic control in the hospital setting. Health-care institutions should develop protocols for the assessment and treatment of hypoglycemia.Key Messages for People with Diabetes•If your admission to hospital is planned, talk with your health-care providers (e.g. surgeon, anesthetist, primary care provider, diabetes health provider, etc.) before you are admitted in order to develop an in-hospital diabetes care plan that addresses such issues as:◦Who will manage your diabetes in the hospital?◦Will you be able to self-manage your diabetes?◦What adjustments to your diabetes medications or insulin doses may be necessary before and after medical procedures or surgery?◦If you use an insulin pump, are hospital staff familiar with pump therapy?•Your blood glucose levels may be higher in hospital than your usual target range due to a variety of factors, including the stress of your illness, medications, medical procedures and infections.•Your diabetes medications may need to be changed during your hospital stay to manage the changes in blood glucose, or if medical conditions develop that make some medications no longer safe to use.•When you are discharged, make sure that you have written instructions about:◦Changes in your dosage of medications or insulin injections or any new medications or treatments◦How often to check your blood glucose◦Who to contact if you have difficulty managing your blood glucose levels. •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.•Insulin is the most appropriate pharmacologic agent for effectively controlling glycemia in hospital. A proactive approach to glycemic management using scheduled basal, bolus and correction (supplemental) insulin is the preferred method. The use of correction-only (supplemental) insulin, which treats hyperglycemia only after it has occurred, should be discouraged as the sole modality for treating elevated blood glucose levels.•For the majority of noncritically ill hospitalized people with diabetes, preprandial blood glucose targets should be 5.0 to 8.0 mmol/L, in conjunction with random blood glucose values <10.0 mmol/L, as long as these targets can be safely achieved. For critically ill hospitalized people with diabetes, blood glucose levels should be maintained between 6.0 and 10.0 mmol/L.•Hypoglycemia is a major barrier to achieving targeted glycemic control in the hospital setting. Health-care institutions should develop protocols for the assessment and treatment of hypoglycemia. •If your admission to hospital is planned, talk with your health-care providers (e.g. surgeon, anesthetist, primary care provider, diabetes health provider, etc.) before you are admitted in order to develop an in-hospital diabetes care plan that addresses such issues as:◦Who will manage your diabetes in the hospital?◦Will you be able to self-manage your diabetes?◦What adjustments to your diabetes medications or insulin doses may be necessary before and after medical procedures or surgery?◦If you use an insulin pump, are hospital staff familiar with pump therapy?•Your blood glucose levels may be higher in hospital than your usual target range due to a variety of factors, including the stress of your illness, medications, medical procedures and infections.•Your diabetes medications may need to be changed during your hospital stay to manage the changes in blood glucose, or if medical conditions develop that make some medications no longer safe to use.•When you are discharged, make sure that you have written instructions about:◦Changes in your dosage of medications or insulin injections or any new medications or treatments◦How often to check your blood glucose◦Who to contact if you have difficulty managing your blood glucose levels. Diabetes increases the risk for hospitalization for several reasons, including: cardiovascular (CV) disease, nephropathy, infection, cancer and lower-extremity amputations. In-hospital hyperglycemia is common. A review of medical records of over 2,000 adult patients admitted to a community teaching hospital in the United States (>85% were nonintensive care unit patients) found that hyperglycemia was present in 38% of patients (1Umpierrez G.E. Isaacs S.D. Bazargan N. et al.Hyperglycemia: An independent marker of in-hospital mortality in patients with undiagnosed diabetes.J Clin Endocrinol Metab. 2002; 87: 978-982Crossref PubMed Scopus (0) Google Scholar). Of these patients, 26% had a known history of diabetes, and 12% had no history of diabetes prior to admission. Diabetes has been reported to be the fourth most common comorbid condition listed on all hospital discharges (2Vasa F. Systematic strategies for improved outcomes for the hyperglycemic hospitalized patient with diabetes mellitus.Am J Cardiol. 2005; 96: 41e-46eAbstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar). Acute illness results in a number of physiological changes (e.g. increases in circulating concentrations of stress hormones) or therapeutic choices (e.g. glucocorticoid use) that can exacerbate hyperglycemia. Hyperglycemia, in turn, causes physiological changes that can exacerbate acute illness, such as decreased immune function and increased oxidative stress. These lead to a complex cycle of worsening illness and poor glucose control (3Inzucchi S.E. Clinical practice. Management of hyperglycemia in the hospital setting.N Engl J Med. 2006; 355: 1903-1911Crossref PubMed Scopus (250) Google Scholar). Although a growing body of literature supports the need for targeted glycemic control in the hospital setting, blood glucose (BG) continues to be poorly controlled and is frequently overlooked in general medicine and surgery services. This is largely explained by the fact that the majority of hospitalizations for patients with diabetes are not directly related to their metabolic state, thus diabetes management is rarely the primary focus of care. Therefore, glycemic control and other diabetes care issues are often not specifically addressed (4Roman S.H. Chassin M.R. Windows of opportunity to improve diabetes care when patients with diabetes are hospitalized for other conditions.Diabetes Care. 2001; 24: 1371-1376Crossref PubMed Google Scholar). A history of diabetes should be elicited in all patients admitted to hospital and, if present, should be clearly identified on the medical record. In view of the high prevalence of inpatient hyperglycemia with associated poor outcomes, an admission BG measurement of all patients would help identify people with diabetes, even in the absence of a prior diagnosis (1Umpierrez G.E. Isaacs S.D. Bazargan N. et al.Hyperglycemia: An independent marker of in-hospital mortality in patients with undiagnosed diabetes.J Clin Endocrinol Metab. 2002; 87: 978-982Crossref PubMed Scopus (0) Google Scholar, 5Sud M. Wang X. Austin P.C. et al.Presentation blood glucose and death, hospitalization, and future diabetes risk in patients with acute heart failure syndromes.Eur Heart J. 2015; 36: 924-931Crossref PubMed Scopus (24) Google Scholar). In-hospital hyperglycemia is defined as any glucose value >7.8 mmol/L. For hospitalized people with known diabetes, the glycated hemoglobin (A1C) identifies people who may benefit from efforts to improve glycemic control and tailor therapy upon discharge (6Umpierrez G.E. Reyes D. Smiley D. et al.Hospital discharge algorithm based on admission HbA1c for the management of patients with type 2 diabetes.Diabetes Care. 2014; 37: 2934-2939Crossref PubMed Scopus (25) Google Scholar, 7Perez A. Reales P. Barahona M.J. et al.Efficacy and feasibility of basal-bolus insulin regimens and a discharge-strategy in hospitalised patients with type 2 diabetes-the HOSMIDIA study.Int J Clin Pract. 2014; 68: 1264-1271Crossref PubMed Scopus (4) Google Scholar). In hospitalized people with newly recognized hyperglycemia, an A1C among those with diabetes risk factors or associated comorbidities (e.g. cardiovascular disease [CVD]) (8Ochoa P.S. Terrell B.T. Vega J.A. et al.Identification of previously undiagnosed diabetes and prediabetes in the inpatient setting using risk factor and hemoglobin A1C screening.Ann Pharmacother. 2014; 48: 1434-1439Crossref PubMed Google Scholar, 9Simpson A.J. Krowka R. Kerrigan J.L. et al.Opportunistic pathology-based screening for diabetes.BMJ Open. 2013; (in press)Crossref Scopus (2) Google Scholar) may help differentiate people with previously undiagnosed diabetes and dysglycemia from those with stress-induced hyperglycemia and provides an opportunity to diagnose and initiate diabetes therapies (10Norhammar A. Tenerz A. Nilsson G. et al.Glucose metabolism in patients with acute myocardial infarction and no previous diagnosis of diabetes mellitus: A prospective study.Lancet. 2002; 359: 2140-2144Abstract Full Text Full Text PDF PubMed Scopus (808) Google Scholar, 11O'Sullivan E.P. Duignan J. O'Shea P. et al.Evaluating hyperglycaemia in the hospitalised patient: Towards an improved system for classification and treatment.Ir J Med Sci. 2014; 183: 65-69Crossref PubMed Scopus (2) Google Scholar, 12Miller D.B. Glycemic targets in hospital and barriers to attaining them.Can J Diabetes. 2014; 38: 74-78Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar, 13Greci L.S. Kailasam M. Malkani S. et al.Utility of HbA(1c) levels for diabetes case finding in hospitalized patients with hyperglycemia.Diabetes Care. 2003; 26: 1064-1068Crossref PubMed Scopus (119) Google Scholar). Among people admitted to an intensive care unit (ICU), an A1C drawn at admission allows identification of people with previously unknown diabetes, people at risk of glycemic management challenges and people at an increased risk of mortality (14Carpenter D.L. Gregg S.R. Xu K. et al.Prevalence and impact of unknown diabetes in the ICU.Crit Care Med. 2015; 43: e541-e550Crossref PubMed Scopus (0) Google Scholar, 15Kompoti M. Michalia M. Salma V. et al.Glycated hemoglobin at admission in the intensive care unit: Clinical implications and prognostic relevance.J Crit Care. 2015; 30: 150-155Abstract Full Text Full Text PDF PubMed Google Scholar). A1C has been found to be specific for diagnosis of diabetes in the hospital setting, although not as sensitive as in the outpatient setting (13Greci L.S. Kailasam M. Malkani S. et al.Utility of HbA(1c) levels for diabetes case finding in hospitalized patients with hyperglycemia.Diabetes Care. 2003; 26: 1064-1068Crossref PubMed Scopus (119) Google Scholar, 16Manley S.E. O'Brien K.T. Quinlan D. et al.Can HbA1c detect undiagnosed diabetes in acute medical hospital admissions?.Diabetes Res Clin Pract. 2016; 115: 106-114Abstract Full Text Full Text PDF PubMed Google Scholar). While the threshold for diagnosis of diabetes has not been established for hospitalized people, an A1C criteria of >6.0% has been found to be highly specific for the diagnosis of dysglycemia post-hospitalization (13Greci L.S. Kailasam M. Malkani S. et al.Utility of HbA(1c) levels for diabetes case finding in hospitalized patients with hyperglycemia.Diabetes Care. 2003; 26: 1064-1068Crossref PubMed Scopus (119) Google Scholar, 17Malcolm J.C. Kocourek J. Keely E. et al.Implementation of a screening program to detect previously undiagnosed dysglycemia in hospitalized patients.Can J Diabetes. 2014; 38: 79-84Abstract Full Text Full Text PDF PubMed Google Scholar). Currently, there are no studies that have examined the effect of the frequency of bedside BG monitoring on the incidence of hyper- or hypoglycemia in the hospital setting. The frequency and timing of bedside BG monitoring can be individualized; however, monitoring is typically performed before meals and at bedtime in people who are eating; every 4 to 6 hours in people who are NPO (nothing by mouth) or receiving continuous enteral feeding; and every 1 to 2 hours for people on continuous intravenous insulin or those who are critically ill. Some bedside BG monitoring is indicated in individuals without known diabetes but receiving treatments known to be associated with hyperglycemia (e.g. glucocorticoids, octreotide, parenteral nutrition and enteral nutrition) (18Umpierrez G.E. Hellman R. Korytkowski M.T. et al.Management of hyperglycemia in hospitalized patients in non-critical care setting: An endocrine society clinical practice guideline.J Clin Endocrinol Metab. 2012; 97: 16-38Crossref PubMed Scopus (415) Google Scholar). The implementation and maintenance of quality control programs by health-care institutions helps to ensure the accuracy of bedside BG monitoring (19Lewandrowski K. Cheek R. Nathan D.M. et al.Implementation of capillary blood glucose monitoring in a teaching hospital and determination of program requirements to maintain quality testing.Am J Med. 1992; 93: 419-426Abstract Full Text PDF PubMed Google Scholar, 20Rumley A.G. Improving the quality of near-patient blood glucose measurement.Ann Clin Biochem. 1997; 34: 281-286Crossref PubMed Scopus (15) Google Scholar). The use of glucose meters with bar coding capability has been shown to reduce data entry errors in medical records (21Boyd J.C. Bruns D.E. Quality specifications for glucose meters: Assessment by simulation modeling of errors in insulin dose.Clin Chem. 2001; 47: 209-214Crossref PubMed Scopus (0) Google Scholar). Data management programs that transfer bedside BG monitoring results into electronic records allow evaluation of hospital-wide glycemic control (22Bates D.W. Leape L.L. Cullen D.J. et al.Effect of computerized physician order entry and a team intervention on prevention of serious medication errors.JAMA. 1998; 280: 1311-1316Crossref PubMed Scopus (1463) Google Scholar). Capillary blood glucose (CBG) point of care testing (POCT) should be interpreted with caution in the critically ill patient population. Poor perfusion indices may yield conflicting capillary, arterial and whole BG values using POCT glucose meters (23Desachy A. Vuagnat A.C. Ghazali A.D. et al.Accuracy of bedside glucometry in critically ill patients: Influence of clinical characteristics and perfusion index.Mayo Clin Proc. 2008; 83: 400-405Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar, 24Critchell C.D. Savarese V. Callahan A. et al.Accuracy of bedside capillary blood glucose measurements in critically ill patients.Intensive Care Med. 2007; 33: 2079-2084Crossref PubMed Scopus (101) Google Scholar, 25Petersen J.R. Graves D.F. Tacker D.H. et al.Comparison of POCT and central laboratory blood glucose results using arterial, capillary, and venous samples from MICU patients on a tight glycemic protocol.Clin Chim Acta. 2008; 396: 10-13Crossref PubMed Scopus (0) Google Scholar). Venous or arterial samples are preferred when using a POCT meter for this patient population. Clinical decision support system software integrating CBG POCT can aid in trend analysis, medication dosing, reduce prescription error and reduce length of stay (26Nirantharakumar K. Chen Y.F. Marshall T. et al.Clinical decision support systems in the care of inpatients with diabetes in non-critical care setting: Systematic review.Diabet Med. 2012; 29: 698-708Crossref PubMed Scopus (0) Google Scholar). Electronic glucose metric data and web-based reporting systems may pose utility for monitoring glycemic management performance within an organization and enhance opportunities for external benchmarking (27Maynard G. Schnipper J.L. Messler J. et al.Design and implementation of a web-based reporting and benchmarking center for inpatient glucometrics.J Diabetes Sci Technol. 2014; 8: 630-640Crossref PubMed Scopus (9) Google Scholar). A number of studies have demonstrated that inpatient hyperglycemia is associated with increased morbidity and mortality in noncritically ill hospitalized people (1Umpierrez G.E. Isaacs S.D. Bazargan N. et al.Hyperglycemia: An independent marker of in-hospital mortality in patients with undiagnosed diabetes.J Clin Endocrinol Metab. 2002; 87: 978-982Crossref PubMed Scopus (0) Google Scholar, 28Baker E.H. Janaway C.H. Philips B.J. et al.Hyperglycaemia is associated with poor outcomes in patients admitted to hospital with acute exacerbations of chronic obstructive pulmonary disease.Thorax. 2006; 61: 284-289Crossref PubMed Scopus (203) Google Scholar, 29McAlister F.A. Majumdar S.R. Blitz S. et al.The relation between hyperglycemia and outcomes in 2,471 patients admitted to the hospital with community-acquired pneumonia.Diabetes Care. 2005; 28: 810-815Crossref PubMed Scopus (247) Google Scholar). However, due to a paucity of randomized controlled trials on the benefits and risks of “conventional” vs. “tight” glycemic control in noncritically ill hospitalized people, glycemic targets for this population remain undefined. Current recommendations are based mostly on retrospective studies, clinical experience and judgement. Glycemic targets for hospitalized people with diabetes are modestly higher than those routinely advised for outpatients with diabetes given that 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 (Table 1) . Lower targets may be considered in clinically stable hospitalized people with a prior history of successful tight glycemic control in the outpatient setting, while higher targets may be acceptable in terminally ill people or in those with severe comorbidities. If BG values are ≤3.9 mmol/L, modification of antihyperglycemic therapy is suggested, unless the event is easily explained by other factors (e.g. a missed meal) (18Umpierrez G.E. Hellman R. Korytkowski M.T. et al.Management of hyperglycemia in hospitalized patients in non-critical care setting: An endocrine society clinical practice guideline.J Clin Endocrinol Metab. 2012; 97: 16-38Crossref PubMed Scopus (415) Google Scholar, 30American Diabetes Association 13. Diabetes care in the hospital.Diabetes Care. 2016; 39: S99-104Crossref PubMed Scopus (18) Google Scholar).Table 1Recommended glycemic targets for hospitalized people with diabetes*Less stringent targets may be appropriate in terminally ill patients or in people with severe comorbidities (see Targets for Glycemic Control chapter, p. S42).Hospitalized population with diabetesBlood glucose targets (mmol/L)Noncritically illPreprandial: 5.0–8.0Random: <10.0Critically ill6.0–10.0CABG intraoperatively5.5–11.1Perioperatively for other surgeries5.0–10.0Acute coronary syndrome†See Management of Acute Coronary Syndromes chapter, p. S190.7.0–10.0Labour and delivery‡See Diabetes and Pregnancy chapter, p. S255.4.0–7.0CABG, coronary artery bypass grafting.* Less stringent targets may be appropriate in terminally ill patients or in people with severe comorbidities (see Targets for Glycemic Control chapter, p. S42).† See Management of Acute Coronary Syndromes chapter, p. S190.‡ See Diabetes and Pregnancy chapter, p. S255. Open table in a new tab CABG, coronary artery bypass grafting. Acute hyperglycemia in the intensive care setting is not unusual and results from a number of factors, including stress-induced counter-regulatory hormone secretion and the effects of medications administered in the ICU (31Lewis K.S. Kane-Gill S.L. Bobek M.B. et al.Intensive insulin therapy for critically ill patients.Ann Pharmacother. 2004; 38: 1243-1251Crossref PubMed Scopus (0) Google Scholar). Glycemic targets for people with pre-existing diabetes who are in the critical care setting have not been firmly established. Early trials showed that achieving normoglycemia (4.4 to 6.1 mmol/L) in cardiac surgery patients or patients in postoperative surgical ICU settings reduced mortality (32van den Berghe G. Wouters P. Weekers F. et al.Intensive insulin therapy in critically ill patients.N Engl J Med. 2001; 345: 1359-1367Crossref PubMed Scopus (7120) Google Scholar). However, subsequent trials in mixed populations of critically ill patients did not show a benefit of targeting BG levels of 4.4 to 8.3 mmol/L. A meta-analysis of trials of intensive insulin therapy in the ICU setting suggested benefit of intensive insulin therapy in surgical patients, but not in medical patients (33Griesdale D.E. de Souza R.J. van Dam R.M. et al.Intensive insulin therapy and mortality among critically ill patients: A meta-analysis including NICE-SUGAR study data.CMAJ. 2009; 180: 821-827Crossref PubMed Scopus (721) Google Scholar). Conversely, the Normoglycemia in Intensive Care Evaluation—Survival Using Glucose Algorithm Regulation (NICE-SUGAR) study, the largest trial to date of intensive glucose control in critically ill medical and surgical patients, found an increase in 90-day all-cause mortality (hazard ratio [HR] 1.14; 95% confidence interval [CI] 1.02–1.28; p=0.02) amongst participants randomized to the intensive glycemic control arm that targeted BG levels of 4.5 to 6.0 mmol/L (34Finfer S. Chittock D.R. et al.NICE-SUGAR Study InvestigatorsIntensive versus conventional glucose control in critically ill patients.N Engl J Med. 2009; 360: 1283-1297Crossref PubMed Scopus (2757) Google Scholar). Furthermore, intensive insulin therapy has been associated with an increased risk of hypoglycemia in the ICU setting (33Griesdale D.E. de Souza R.J. van Dam R.M. et al.Intensive insulin therapy and mortality among critically ill patients: A meta-analysis including NICE-SUGAR study data.CMAJ. 2009; 180: 821-827Crossref PubMed Scopus (721) Google Scholar). Therefore, maintaining a BG level <10.0 mmol/L in critically ill hospitalized people with diabetes is considered a safe target (Table 1). The lower limit for the BG target is less well established but generally should remain >6.0 mmol/L in order to minimize the risks of both hypoglycemia and mortality. The use of insulin infusion protocols with proven efficacy and safety minimizes the risk of hypoglycemia (35Moghissi E.S. Korytkowski M.T. DiNardo M. et al.American Association of Clinical Endocrinologists and American Diabetes Association consensus statement on inpatient glycemic control.Endocr Pract. 2009; 15: 353-369Crossref PubMed Scopus (352) Google Scholar, 36Goldberg P.A. Siegel M.D. Sherwin R.S. et al.Implementation of a safe and effective insulin infusion protocol in a medical intensive care unit.Diabetes Care. 2004; 27: 461-467Crossref PubMed Scopus (345) Google Scholar, 37Rea R.S. Donihi A.C. Bobeck M. et al.Implementing an intravenous insulin infusion protocol in the intensive care unit.Am J Health Syst Pharm. 2007; 64: 385-395Crossref PubMed Scopus (0) Google Scholar, 38Nazer L.H. Chow S.L. Moghissi E.S. Insulin infusion protocols for critically ill patients: A highlight of differences and similarities.Endocr Pract. 2007; 13: 137-146Crossref PubMed Scopus (32) Google Scholar). There are few occasions when intravenous insulin is required, as most people with type 1 or type 2 diabetes admitted to general medical wards can be treated with subcutaneous insulin. Intravenous insulin, however, may be appropriate for people who are critically ill (with appropriate BG targets), people who are not eating and in those with hyperglycemia and metabolic decompensation (e.g. diabetic ketoacidosis [DKA] and hyperosmolar hyperglycemic state [HHS]) (see Hyperglycemic Emergencies in Adults chapter, p. S109). The evidence to date suggests there is no benefit to intravenous insulin over subcutaneous insulin post-acute stroke (3Inzucchi S.E. Clinical practice. Management of hyperglycemia in the hospital setting.N Engl J Med. 2006; 355: 1903-1911Crossref PubMed Scopus (250) Google Scholar, 39Ntaios G. Papavasileiou V. Bargiota A. et al.Intravenous insulin treatment in acute stroke: A systematic review and meta-analysis of randomized controlled trials.Int J Stroke. 2014; 9: 489-493Crossref PubMed Scopus (14) Google Scholar). Health-care staff education is a critical component of the implementation of an intravenous insulin infusion protocol. Intravenous insulin protocols should take into account the patient's current and previous BG levels (as well as the rate of change in BG), and the patient's usual insulin dose. Several published insulin infusion protocols appear to be both safe and effective, with low rates of hypoglycemia; however, most of these protocols have only been validated in the ICU setting, where the nurse-to-patient ratio is higher than on medical and surgical wards (3Inzucchi S.E. Clinical practice. Management of hyperglycemia in the hospital setting.N Engl J Med. 2006; 355: 1903-1911Crossref PubMed Scopus (250) Google Scholar, 36Goldberg P.A. Siegel M.D. Sherwin R.S. et al.Implementation of a safe and effective insulin infusion protocol in a medical intensive care unit.Diabetes Care. 2004; 27: 461-467Crossref PubMed Scopus (345) Google Scholar). BG determinations can be performed every 1 to 2 hours until BG has stabilized. With the exception of the treatment of hyperglycemic emergencies (e.g. DKA and HHS), consideration should be given to concurrently providing people receiving intravenous insulin with some form of glucose (e.g. intravenous glucose or through parenteral or enteral feeding). Hospitalized people with type 1 and type 2 diabetes may be transitioned to scheduled subcutaneous insulin therapy from intravenous insulin. Short- or rapid- or fast-acting insulin can be administered 1 to 2 hours before discontinuation of the intravenous insulin to maintain effective blood levels of insulin. If intermediate- or long-acting insulin is used, it can be given 2 to 3 hours prior to intravenous insulin discontinuation. People without a history of diabetes, who have hyperglycemia requiring more than 2 units of intravenous insulin per hour, likely require insulin therapy and can be considered for transition to scheduled subcutaneous insulin therapy. The initial dose and distribution of subcutaneous insulin at the time of transition can be determined by extrapolating the intravenous insulin requirement over the preceding 6- to 8-hour period to a 24-hour period. Administering 60% to 80% of the total daily calculated dose as basal insulin has been demonstrated to be safe and efficacious in surgical patients (40Schmeltz L.R. DeSantis A.J. Schmidt K. et al.Conversion of intravenous insulin infusions to subcutaneously administered insulin glargine in patients with hyperglycemia.Endocr Pract. 2006; 12: 641-650Crossref PubMed Scopus (79) Google Scholar). Dividing the total daily dose as a combination of basal and bolus insulin has been demonstrated to be safe and efficacious in medically ill patients (40Schmeltz L.R. DeSantis A.J. Schmidt K. et al.Conversion of intravenous insulin infusions to subcutaneously administered insulin glargine in patients with hyperglycemia.Endocr Pract. 2006; 12: 641-650Crossref PubMed Scopus (79) Google Scholar, 41Bode B.W. Braithwaite S.S. Steed R.D. et al.Intravenous insulin infusion therapy: Indications, methods, and transition to subcutaneous insulin therapy.Endocr Pract. 2004; 10: 71-80Crossref PubMed Google Scholar). The management of individuals with diabetes at the time of surgery poses a number of challenges. Acute hyperglycemia is common secondary to the physiological stress associated with surgery. Pre-existing diabetes-related complications and comorbidities may also influence clinical outcomes. Acute hyperglycemia has been shown to adversely affect immune function (42Kwoun M.O. Ling P.R. 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