23 Dec 10
By B Kavanagh and K McCowen
NEJM 2010; 363:2540-2546
This Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the authors’ clinical recommendations.
A 42-year-old man is admitted to the intensive care unit (ICU) with an acute exacerbation of asthma associated with community-acquired pneumonia. He is treated with cefotaxime and azithromycin, nebulized albuterol, and intravenous hydrocortisone. He has no known history of diabetes mellitus. Shortly after admission, his arterial glucose concentration is 105 mg per deciliter (5.8 mmol per liter), and on the next day, it has increased to 195 mg per deciliter (10.8 mmol per liter). His glycated hemoglobin level is 5.3%. Should this elevated glucose level be treated?
24 Apr 10
By M Hoekstra, M Vogelzang, E Verbitskiy and M Nijsten
Critical Care 2010, 14:404
In the recently published work of Juneja and colleagues the authors describe the excellent results of a computerized insulin dosing algorithm (Clarian GlucoStabilizer™). To prevent hypoglycemia, however, the authors note that frequent (that is, hourly) measurements are required. We believe that, with an adequate algorithm, the required level of glucose control can be reached without hourly glucose measurements.
25 Nov 09
By Y Arabi, H Tamim, A Rishu
Critical Care Medicine 2009;37:2536-2544
To examine the predisposing factors for hypoglycemia in medical-surgical intensive care unit patients treated with intensive insulin therapy and to assess its association with mortality.
Nested-cohort study within a randomized controlled trial.
Tertiary care intensive care unit.
Medical-surgical intensive care unit patients with admission blood glucose of >6.1 mmol/L or 110 mg/dL who were enrolled in a randomized controlled trial comparing intensive insulin therapy with conventional insulin therapy.
Hypoglycemia was defined as blood glucose <=2.2 mmol/L or 40 mg/dL and intensive care unit mortality was the primary outcome.
Measurements and main results
Among the 523 patients included in the study, hypoglycemia occurred in 84 (16%). Intensive insulin therapy was independently associated with increased risk of hypoglycemia (adjusted odds ratio, 50.65; 95% confidence interval, 17.36-147.78; p < .0001). Other variables associated with an increased risk of hypoglycemia included female gender, diabetes, Acute Physiology and Chronic Health Evaluation II, mechanical ventilation, continuous veno-venous hemodialysis, and intensive care unit length of stay. When adjusted to potential confounders, hypoglycemia was not significantly associated with increased mortality (adjusted hazard ratio, 1.31; 95% confidence interval, .70-2.46; p = .40). Patients with admission blood glucose of <=10 mmol/L had an increased mortality with hypoglycemia (adjusted hazard ratio, 4.43; 95% confidence interval, 1.36-14.44; p = .01). Crude analysis showed significant association of mortality with blood glucose levels of <=1.2 mmol/L (adjusted hazard ratio, 2.92; 95% confidence interval, 1.05-8.11; p = .04). When adjusted analysis was performed, similar trend was seen but was not statistically significant (adjusted hazard ratio, 2.56; 95% confidence interval, .85-7.70; p = .10).
Our study showed significant increase of hypoglycemia with intensive insulin therapy. Although hypoglycemia was not independently associated with increased risk of death, increased mortality could not be excluded with severe hypoglycemia and in patients admitted with blood glucose of <=10 mmol/L.
16 Nov 09
By I Meynaar, M van Spreuwel, P Tangkau, L Dawson, S Visser, L Rijks, T Vlieland
Crit Care Med 2009; 37:2691-2696
To evaluate the accuracy of the AccuChek Inform point-of-care glucose measurement device as compared with central laboratory glucose measurement.
Prospective, observational study.
A ten-bed mixed closed format intensive care unit in a 500-bed general hospital. The unit has a computerized insulin protocol aiming for 81 to 135 mg/dL.
All intensive care unit patients were eligible.
Measurements and main results
Paired samples (AccuChek glucose in whole blood calibrated to give whole blood results and central laboratory glucose in serum) were taken simultaneously. In 32 critically ill patients, we obtained the following information: mean ± standard deviation age 71.6 ± 11.9 yrs; mean Acute Physiology and Chronic Health Evaluation II score at admission 17.8 ± 6.7; 239 paired samples were taken from arterial catheters. Mean AccuChek whole blood glucose was 126 ± 36 mg/dL (7.0 ± 2.0 mmol/L); mean central laboratory serum glucose was 137 ± 38 mg/dL (7.6 ± 2.1 mmol/L). Mean difference was 11 mg/dL (0.61 mmol/L) (8%) (95% Confidence Interval = 9-13 mg/dL, p < .001). ISO 15197 guideline requires 95% of point-of-care measurements to be within 15 mg/dL margins with reference <75 mg/dL or within 20% if reference is higher. In total, 216 (90.4%) of AccuChek measurements were within ISO 15197 margins. Because AccuChek was calibrated to give whole blood results, we calculated a correction factor of 1.086 from the two mean values to correct whole blood AccuChek into serum-like results. This is almost the same as the correction factor of 1.080 given by Roche Diagnostics. By multiplying AccuChek whole blood results with 1.086, 225 (94.1%) of results were within the ISO 15197 margins. Hematocrit did not influence AccuChek results in the 0.20 to 0.44 range. Beyond this range, there were not enough data to draw conclusions.
In critically ill patients, the accuracy of AccuChek glucose measurement calibrated to give serum-like results with blood samples derived from arterial catheters is acceptable but falls short by about 1% of complying with the ISO 15197 guideline.