Hypoglycemia in the ICU: Discrepancy between capillary and serum glucose measurements in patients with renal disease

Ruth A. Verner, Maguy Chiha, Mary Ann Emanuele, Alaleh Mazhari

Division of Endocrinology and Metabolism, Department of Medicine, Loyola University Medical Center, Maywood, USA;.

DOI: 10.4236/crcm.2013.24069                

Abstract

Recently, a focus on tight glycemic control in intensive care units (ICU) has resulted in implementation of strict insulin protocols requiring frequent glucose monitoring. The use of point-of-care (POC) capillary glucose testing is widespread, but its validity in the ICU has been questioned. Our objective is to better understand the use of POC glucose at the extremes of glycemic control through a case review at our institution. We describe the case of a 75-year-old non-diabetic female with end stage renal disease (ESRD) on hemodialysis who was admitted with apparent hypoglycemia. After extensive workup was done for a seemingly refractive hypoglycemia, a discrepancy between POC capillary glucose and central serum glucose levels was discovered, revealing actual euglycemia and false low POC glucose values. Cases of hypoglycemia can be challenging, especially in non-diabetic patients with ESRD. While glucometers assessing capillary glucose are used both in the outpatient and inpatient environment, their validity in the critically ill patient has known limitations. Cases such as this have led to the development of systemic checks and balances, as well as further investigations regarding the use of POC glucose meters in the ICU. This case serves as a reminder to evaluate for all causes for abnormal laboratory values, including technological limitations.

Keywords

Point-of-Care; Hypoglycemia; ICU

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Cryer, P.E., et al. (2009) Evaluation and management of adult hypoglycemic disorders: An endocrine society clinical practice guideline. Journal of Clinical Endocrinology and Metabolism, 94, 709-728. doi:10.1210/jc.2008-1410
[2]	Mak, R.H.K. (2000) Impact of end-stage renal disease and dialysis on glycemic control. Seminars in Dialysis, 13, 4-8. doi:10.1046/j.1525-139x.2000.00007.x
[3]	Strumvoll, M. (1998) Glucose production by the human kidney—Its importance has been underestimated. Nephrology Dialysis Transplant, 13, 2996-2999. doi:10.1093/ndt/13.12.2996
[4]	Triplett, C.L. (2012) Understanding the kidney’s role in blood glucose regulation. American Journal of Managed Care, 18, S11-S16.
[5]	Van den Berghe, G., et al. (2001) Intensive insulin therapy in critically ill patients. New England Journal of Medicine, 345, 1359-1367. doi:10.1056/NEJMoa011300
[6]	Griesdale, D. et al. (2009) Intensive insulin therapy and mortality among critically ill patients: A meta-analysis including NICE-SUGAR study data. Canadian Medical Association Journal, 180, 821-827. doi:10.1503/cmaj.090206
[7]	The Nice Sugar Investigators (2009) Intensive versus conventional glucose control in critically ill patients. The New England Journal of Medicine, 360, 1283-1297. doi:10.1056/NEJMoa0810625
[8]	Khan, A.I., et al. (2006) The variability of results between point-of-care testing glucose meters and the central laboratory analyzer. Archives of Pathological Lab Medicine, 130, 1527-1532.
[9]	Kanjii, S., et al. (2005) Reliability of point-of-care testing for glucose measurement in critically ill adults. Critical Care Medicine, 33, 2778-2785. doi:10.1097/01.CCM.0000189939.10881.60
[10]	Ginsburg, B.H. (2009) Factors affecting blood glucose monitoring: Sources of error in measurement. Journal of Diabetes Science and Technology, 3, 903-913.
[11]	Nichols, J.H. (2011) Blood glucose testing in the hospital: Error sources and risk management. Journal of Diabetes Science and Technology, 5, 173-177.
[12]	Roche Diagnostics (2013) Hematocrit variable study protocol for glucose meter evaluations.
[13]	Gijzen, K., et al. (2012) Is there a suitable point-of-care glucose meter for tight glycemic control? Evaluation of one home-use and four hospital-use meters in an intensive care unit. Clinical Chemistry and Laboratory Medicine, 50, 1985-1992.
[14]	Critchell, C.D., et al. (2007) Accuracy of bedside capillary blood glucose measurements in critically ill patients. Intensive Care Medicine, 33, 2079-2084.