The impact of basal bolus and sliding scale insulin management on dosing administration errors in the hospital setting

Background: Insulin is consistently among the top five medications associated with administration errors in the hospital setting. The sliding scale insulin (SSI) therapy used for control of inpatient hyperglycaemia is largely ineffective in controlling inpatient blood glucose levels, and guidelines now advocate the use of basal bolus insulin (BBI) therapy. However, SSI is still extensively used in hospitals worldwide. There is little published literature evaluating issues surrounding the administration accuracy using a BBI approach compared with that for SSI. Aim: To assess dosing administration accuracy of SSI versus BBI regimens in patients undergoing glycaemic management in a tertiary teaching hospital, and the subsequent impact on the following blood glucose level. Methods: Data were collected prospectively for the BBI arm and retrospectively for the SSI arm for the first 5 days of treatment in hospitalized patients requiring glycaemic management. Records were assessed for the incidence of omitted doses, or administered doses that were higher or lower than those prescribed. Results: For the SSI regimen (n = 25 patients, 251 doses), 16.3% of doses were missed compared to 2.5% of doses for BBI (n = 21 patients, 467 doses, p < 0.001).Low doses in the SSI and BBI arms occurred at incidence rates of 8.7% and 8.8% respectively (p = 0.96), while high dose incidence rates were 2.3% and 0% respectively (p = 0.004). When patients received less than the prescribed amount (either a low or missed insulin dose), the subsequent blood glucose was 1.8 mmol/L higher for BBI (p = 0.032) relative to correctly administered doses and 2.0 mmol/Lhigher for SSI (p = 0.038). Only one omitted dose incident for SSI and two incidents for BBI were formally reported as dosing errors. Conclusion: BBI management resulted in more accurate dosing administration, especially with regard to reducing the incidence of omitted doses. The administration of lower-than-prescribed doses adversely impacted subsequent blood glucose control.