Abstract
Variable rate intravenous insulin infusions (VRIII) are frequently used in hospitals and incorrect use can lead to electrolyte imbalance, hypoglycaemia and adverse outcomes. The Joint British Diabetes Societies (JDBS) published guidelines in 2014 and recommended the use of a balanced fluid as substrate. There was no published data to demonstrate the superiority of this fluid in reducing adverse events. This quality improvement project aimed to review the existing practice at our Trust in accordance with JDBS guidelines. We predicted introducing this fluid would reduce adverse events and demonstrating this was a prerequisite condition from our Trust Medicines Management Committee to approve its long-term availability. We carried out an audit of our practice in 2015, at which time the JBDS recommended fluid (0.45% sodium chloride/5% dextrose with 0.15% potassium chloride) was not available in our Trust. Our VRIII guideline was re-written with recommendation for use of the balanced fluid, after procurement from pharmacy. Our primary areas for improvement as highlighted from the 2015 audit were correct substrate prescription and rate reduction of hypokalaemia (potassium <3.5 mmol/L) and hypoglycaemia (glucose <4 mmol/L) during VRIII use. Analysis of the pre-intervention (December 2016) and post-intervention (September-November 2017) data showed a significant increase in correct fluid use; 11% pre-intervention to 76% post-intervention (χ(2), p<0.0001). The number of hypoglycaemic events per VRIII reduced from 0.73 (±1.78) to 0.28 (±0.84) (p<0.05) peri-intervention. Similarly, the number of hypokalaemic events per VRIII reduced from 0.15 (±0.54) pre-intervention to 0.05 (±0.25) post-intervention. There was also a significant reduction in number of VRIII episodes associated with a hyponatraemia event from 26% at baseline to 12% post-intervention (p<0.01). Some of these marked improvements were not sustained at 1-year post follow-up. We reduced adverse outcomes with a substantial net-cost saving during this period, through implementation of new and accessible guidelines, trust-wide education programmes and posters to raise awareness.