Accuracy and reliability of continuous blood glucose monitor in post-surgical patients

The STG-22 is the only continuous blood glucose monitoring system currently available. The aim of this study is to determine the accuracy and reliability of the STG-22 for continuously monitoring blood glucose level in post-surgical patients.

Fifty patients scheduled for routine surgery were studied in surgical intensive care unit (ICU) of a university hospital. After admission to the ICU, the STG-22 was connected to the patients. An attending physician obtained blood samples from a radial arterial catheter. Blood glucose level was measured using the ABL800FLEX immediately after blood collection at 0, 4, 8, and 16 h post-admission to the ICU (total of 200 blood glucose values).

The correlation coefficient (R2) was 0.96. In the Clarke error grid, 100% of the paired measurements were in the clinically acceptable zone A and B. The Bland and Altman analysis showed that bias+/-limits of agreement (percent error) were 0.04(0.7)+/-0.35(6.3) mmol (mg/dl) (7%), -0.11(-2)+/-1.22(22) (15%) and -0.33(-6)+/-1.28(23) (10%) in hypoglycemia (<70(3.89) mmol (mg/dl), normoglycemia (3.89(70)-10(180) mmol (mg/dl), and hyperglycemia (>10(180) mmol (mg/dl), respectively.

The STG-22 can be used for measuring blood glucose level continuously and measurement results are consistent with intermittent measurement (percentage error within 15%). Therefore, the STG-22 is a useful device for monitoring in blood glucose level in the ICU for 16 h.