In the January WMSHP Newsletter, Brenda (Schulz) McCracken, a PGY-1 Pharmacy Resident at Spectrum Health, writes about managing hyperglycemia at her institution using basal-bolus insulin order sets.

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Importance of Inpatient Hyperglycemic Management

Brenda J. (Schulz) McCracken, PharmD
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When insulin is ordered for a patient who has high blood glucose levels, practitioners tend to think that the patient must have a history of diabetes mellitus (DM). However, this is not necessarily true. In a study by Umpierrez et al (2002), hyperglycemia was present in 38% of patients admitted to the hospital, of which 12% had no history of DM before the admission.1 If the patients do not even have DM, why are their blood glucose levels elevated and why do practitioners bother initiating the patients on insulin therapy while in the hospital? Will high blood glucose levels for a few days really affect anything?

It has been shown that hyperglycemia may be an independent risk factor for an increased risk of infection.² In fact, patients with poor glucose control (at least one blood glucose value >220 mg/dL) undergoing major cardiovascular or abdominal surgery are at nearly 6 times the risk of serious postoperative nosocomial infections compared to patients with adequate blood glucose control (all blood glucose values ≤220 mg/dL).² Hyperglycemia can also lead to increased morbidity and mortality in patients undergoing coronary artery bypass grafting and in patients with stroke.^2-5

A landmark study by Van den Berghe et al (2001) showed that maintaining controlled blood glucose levels via insulin continuous infusions significantly improved clinical outcomes among critically ill patients.^6,7 This trial demonstrated a 43% reduction of intensive care unit (ICU) mortality and a 34% decrease in overall hospital mortality in patients whose average blood glucose levels were maintained at 103 mg/dL, with a target range of 80-110 mg/dL. The strict control of blood glucose was associated with fewer blood stream infections, reduced frequency of neuropathy, lower incidence of dialysis-dependent renal failure, fewer blood transfusions, and less need for mechanical ventilation. In addition, more recent studies have shown that poor blood glucose control is related to adverse outcomes, including mortality, infectious complications, longer hospital stays, and more costly care.⁶

Although attention is often focused on controlling blood glucose levels in patients undergoing major surgeries and patients in the ICU, hyperglycemia is actually a major issue for all other inpatients as well. In fact, it is normal for many patients to have what is termed “stress hyperglycemia,” which is elevated blood glucose levels associated with acute illness.⁶ The body naturally increases blood glucose levels in response to injury, stress, certain medications, severe illness, or surgery. Even though hyperglycemia may be a natural response to illness for some patients, numerous studies have clearly shown that uncontrolled hyperglycemia negatively affects patient outcomes.^2-7 As a result, tight glycemic control for all inpatients is becoming a healthcare priority and a standard of care.⁶ The recommended targets for blood glucose levels in hospitalized patients according to the American Diabetes Association are shown below in Table 1.⁹

Table 1⁹

Patient Population	Goal Blood Glucose Levels
Critically ill patients	As close to 110 mg/dL as possible and generally <180 mg/dL
Non-critically ill patients	Pre-meal (fasting): As close to 90-130 mg/dL as possible and generally around 110 mg/dL Postprandial: <180 mg/dL

In response to research showing the significant benefits of controlling inpatient hyperglycemia, Spectrum Health has recently implemented new basal-bolus insulin order sets. In addition, all sliding scale insulin order sets have now been officially eliminated at Spectrum Health in order to provide tighter glycemic control for our patients through evidence-based medicine. Basal-bolus insulin regimens more closely mimic the body’s natural physiologic secretion of insulin (Figure 1) and provide continuous 24-hour coverage with basal insulin (i.e. insulin glargine). Also, basal-bolus regimens use a proactive rather than reactive approach to prevent future episodes of hyperglycemia. On the other hand, sliding scale regimens did not provide any insulin to patients until their blood glucose levels were already significantly elevated and the rapid-acting insulin doses often over-corrected the blood glucose level, resulting in undesirable frequent episodes of hypoglycemia.

Fear of hypoglycemia is the primary barrier to achieving target blood glucose levels in patients.⁶ Many healthcare providers are more concerned about avoiding hypoglycemia rather than detecting and controlling hyperglycemia, which is potentially the more profound threat to inpatient safety.⁶ Instead of reducing insulin therapy to avoid hypoglycemia, several strategies can be used to prevent it, such as increasing the frequency of blood glucose monitoring, establishing higher thresholds for withholding insulin doses, and adjusting for changes in the patient’s medical status and nutritional intake (i.e. new NPO status, interruption of TPN or IV dextrose infusions, tapering of steroid medications, etc).

With strict hyperglycemic management and the appropriate use of insulin therapy, Spectrum Health can reduce hospital lengths of stay, decrease costs, improve therapeutic outcomes, and prevent patient mortality.

 

References:

1. Umpierrez GE, Isaacs SD, Bazargan N, You X, Thaler LM, Kitabchi AE. Hyperglycemia: an independent marker of in-hospital mortality in patients with undiagnosed diabetes. J Clin Endocrinol Metab. 2002 Mar;87(3)978-82.
2. Pomposelli JJ, Baxter JK 3rd, Babineau TJ, Pomfret EA, Driscoll DF, Forse RA, et al. Early postoperative glucose control predicts nosocomial infection rate in diabetic patients. JPEN J Parenter Enteral Nutr. 1998 Mar-Apr;22(2):77-81.
3. Furnary AP, Gao G, Grunkemeier GL, Wu Y, Zerr KJ, Bookin SO, et al. Continuous insulin infusion reduces mortality in patients with diabetes undergoing coronary artery bypass grafting. J Thorac Cardiovasc Surg. 2003 May;125(5):1007-21.
4. Weir CJ, Murray GD, Dyker AG, Lees KR. Is hyperglycaemia an independent predictor of poor outcome after acute stroke? Results of a long-term follow up study. BMJ. 1997 May 3;314(7090):1303-6.
5. Jorgensen H, Nakayama H, Raaschou HO, Olsen TS. Stroke in patients with diabetes. The Copenhagen Stroke Study. Stroke. 1994 Oct;25(10):1977-84.
6. Hirsch IB, Braithwaite SS, Verderese CA. Practical management of inpatient hyperglycemia. Lakeville (CT): Hilliard; 2005.
7. Van den Berghe G, Wouters P, Weekers F, Verwaest C, Bruyninckx F, Schetz M, et al. Intensive insulin therapy in the critically ill patients. N Engl J Med. 2001 Nov 8;345(19):1359-67.
8. Ergun-Longmire B, Ten S, Maclaren N. Management of type-1 and type-2 diabetes in children. In: New M, editor. Pediatric endocrinology. 2005 May 5. Available from: http://www.endotext.org/pediatrics/
9. American Diabetes Association. Standards of medical care in diabetes. Diabetes Care. 2005;28:S4-S36.