Use of a glucose management service improves glycemic control following vascular surgery: an interrupted time-series study

Abstract

Background: The optimal method for obtaining good blood glucose control in noncritically ill patients undergoing peripheral vascular surgery remains a topic of debate for surgeons, endocrinologists, and others involved in the care of patients with peripheral arterial disease and diabetes. A prospective trial was performed to evaluate the impact of routine use of a glucose management service (GMS) on glycemic control within 24 hours of lower-extremity revascularization (LER).

Methods: In an interrupted time-series design (May 1, 2011-April 30, 2012), surgeon-directed diabetic care (Baseline phase) to routine GMS involvement (Intervention phase) was compared following LER. GMS assumed responsibility for glucose management through discharge. The main outcome measure was glycemic control, assessed by (1) mean hospitalization glucose and (2) the percentage of recorded glucose values within target range. Statistical process control charts were used to assess the impact of the intervention.

Results: Clinically important differences in patient demographics were noted between groups; the 19 patients in the Intervention arm had worse peripheral vascular disease than the 19 patients in the Baseline arm (74% critical limb ischemia versus 58%; p = .63). Routine use of GMS significantly reduced mean hospitalization glucose (191 mg/dL Baseline versus 150 mg/dL Intervention, p < .001). Further, the proportion of glucose values in target range increased (48% Baseline versus 78% Intervention, p = .05). Following removal of GMS involvement, measures of glycemic control did not significantly decrease for the 19 postintervention patients.

Conclusions: Routine involvement of GMS improved glycemic control in patients undergoing LER. Future work is needed to examine the impact of improved glycemic control on clinical outcomes following LER.

Figure 1

Statistical process control i-charts demonstrate a special-cause signal beginning with the 20th patient enrolled in the study, where there is a shift in the data, defined by > 8 consecutive measurements below the median measurement. This indicates a significant improvement in mean hospitalization glucose following the intervention. UCL, upper control limit; CEN, center (mean); LCL, lower control limit.

Figure 2

Statistical process control p-charts demonstrate a significant improvement in the proportion of glucose values within target range among individuals following in the intervention period. On average, the proportion of glucose values in target range during the Baseline period of the study was only 48%—which increased to an average of 78% during the Intervention phase, with many individuals achieving 100% of their values within the target range. UCL, upper control limit; CEN, center (mean); UCL, lower control limit.