The following post was written several years ago. Although more recent developments have changed the field of clinical laboratory science since the original posting, the information contained was deemed to be of historical interest.
It has been roughly 10 years since the first published studies reported that controlling a hospitalized inpatient’s blood glucose level within a narrow range could impact clinical outcomes to potentially have a significant and beneficial effect on the risk of illness or death (1-3). These early reports focused on critically ill surgical ICU patients treated with intensive insulin therapy protocols aimed at trying to tightly control blood glucose levels within an almost normal range such as 80 – 110 mg/dl. These findings had an immediate and dramatic impact on the practice of medicine as clinical investigators as well as practicing clinicians quickly began to study and expand use of these protocols to other patient groups.
The complex clinical findings, passionate debate and, often, heated controversy regarding use of intensive insulin therapy for tight glycemic control have keenly interested major stakeholders ever since. This area continues to be a fascinating and evolving chapter in both clinical and laboratory medicine (4). Seeking to replicate protocol benefits from a multitude of more recently published studies, many clinicians have recognized the benefits of glycemic control protocols for their hospitalized patients. But not all the published studies report positive findings. Findings from multicenter studies including a meta-analysis reported that tight glycemic control was associated with increased mortality and an increased risk of hypoglycemia as well as being strongly associated with an increased risk of vascular events and death (5-8). But questions have also been raised about the design, data analysis or other aspects of some of these studies (9).
To address protocol issues such as increased hypoglycemic risk, many institutions have now revised intensive insulin therapy protocols to more moderate glycemic control with targets roughly in the 120 – 170 mg/dl range. Moving towards standardizing sound clinical practices, a number of clinical societies and groups have also developed consensus statements or guidelines that focus on handling important areas of concern in the use of these protocols including an emphasis on patient safety (10).
One key issue of focus and controversy continues to be the method by which glucose is measured. In the earliest reports, blood gas analyzers were used for measurement. But a decade’s growth in this practice worldwide has resulted in an increasingly high percentage and, very likely a significant majority, of institutions employing glucose meters for this purpose instead. Key concerns and questions continue to be raised on whether the current state of glucose meter performance truly allows for their use in tight or even moderate glycemic control protocols (11, 12). This area is also one of active interest and is currently a focus of national and international regulatory and standardization groups.
Thought leaders continue to recognize new and different issues to improve practice as well as implement paradigms for changing practice in the application of glycemic control protocols for inpatient management. Benefits have been reported with use of insulin dosing software and other algorithms.; Many institutions participate in large regional or national benchmark programs for quality assurance purposes. What are the unique, present practices and experiences with these protocols at your institution? Has their use been modified in recent years moving from protocols for tight glycemic to more moderate glycemic control targets and ranges as well as having been modified in other ways?
- Van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin therapy in critically ill patients. N Engl J Med 2001; 345: 1359-67.
- Van den Berghe G, Wilmer A, Herman G, et al. Intensive insulin therapy in the medical ICU. N Engl J Med 2006; 354:449 – 61.
- Arabi YM, Dabbagh OC, Tamin HM, et al. Intensive versus conventional insulin therapy; a randomized controlled trial in medical and surgical critically ill patients. Crit Care Med 2008; 36: 3190 -7.
- Kavanagh BP, McCowen KC. Glycemic control in the ICU. N Engl J Med 2010; 363: 2540-6.
- Finfer S, Delaney A. Tight glycemic control in critically ill adults. JAMA 2008; 100: 963 – 5.
- Wiener RS, Wiener DC, Larson RJ. Benefits and risks of tight glucose control in critically ill adults: A meta-analysis.; JAMA 2008; 300: 933-44.
- The NICE-Sugar Study Investigators. Intensive versus conventional glucose control in critically ill patients. N Engl J Med 2009; 360: 1283-97.
- Zoungas S, Patel A, Chalmers J, et al. Severe hypoglycemic and risks of vascular events and death. N Engl J Med 2010; 363: 1420 – 8.
- Scott MG, Bruns DE, Sacks DB. Tight glucose control in critically ill adults. JAMA 2008; 300: 2725-6.
- Hellman R. Patient safety and inpatient glycemic control: translating concepts into action. Endo Pract 2006; 12 [Suppl 3]: 49 – 55.
- Scott MG, Bruns DE, Boyd JC, Sacks DB. Tight glucose control in the intensive care unit: Are glucose meters up to the task? ClinChem 2009; 55: 18 – 20.
- Karon BS, Boyd JC, Klee GG. Glucose meter performance criteria for tight glycemic control estimated by simulation modeling. ClinChem 2010; 56: 1091-7.