Is nurse-managed blood glucose control in critical care as safe and effective as the traditional sliding scale method?

Summary 

Background

Hyperglycaemia occurs in a substantial proportion of critically ill patients. Recent studies have demonstrated that controlling blood glucose in critically ill patients can improve outcomes (Boord et al., 2001). Traditionally, blood glucose is controlled by the sliding scale method. A pre-defined dose of intravenous insulin is infused for each glucose level. Revisions to the prescription are frequently necessary when it is ineffective. The objective of this review is to assess the effectiveness, safety and feasibility of nurse-managed protocols that require minimal physician input.

Methods

An electronic search was performed on the Medline, CINAHL and EMBASE databases from 1996 to 2008. The objective of this work was to assess nurse-managed glycaemic control in critically ill patients. The target blood glucose was required to be less than 8.3mmol/L.

Results

Fourteen papers met the inclusion criteria. Eight studies compared their protocol to the previous method of glucose control (Table 1). In all cases there was an improvement. Time to reach target was less and time spent within target range was greater. All but one study reduced episodes of hypoglycaemia with the new protocol. Six studies developed their protocol as a quality improvement project and did not use a control group (Table 2).

Conclusion

An insulin infusion protocol (IIP) that uses the last two blood glucose levels in order to determine the new infusion rate is better at maintaining glycaemic control than the traditional sliding scale method. A protocol that allows a nurse to commence and maintain the infusion is as safe and more effective than the traditional sliding scale method.

Keywords: Critical care, Nurse-managed, Blood glucose, Sliding scale