British Journal of Anaesthesia, 2000, Vol. 84, No. 5 687
© 2000 The Board of Management and Trustees of the British Journal of Anaesthesia
Abstract |
Impact of a standard insulin sliding scale on the efficacy of controlling blood glucose levels in the critically ill
1 Department of Adult Intensive Care, Guy’s and St Thomas Hospitals, Lambeth Palace Road, London SE1 7EH, UK
Abstract
We tested the hypothesis that a standard insulin sliding scale as a starting point for insulin therapy in the critically ill would improve control of blood glucose levels as evidenced by decreased times to achieve a blood glucose level (BGL) of less than 10 mmol litre–1 from the commencement of intravenous insulin. The current practice guidelines dictate that BGL’s should initially be done hourly when abnormal and insulin therapy started if the BGL is greater than 10 mmol litre–1 for 3 h. We audited the efficacy of these guidelines over a 4-week period and repeated this process following introduction of a standard insulin sliding scale (Table 34) as a starting point for insulin therapy.
There were 15 patients who required insulin infusions in the first 4-week period. The mean time taken to initiate therapy following the third abnormal BGL was 3.3 h and to achieve a BGL of <10 mmol litre–1 was 8.2 h, the mean time taken between the first and third abnormal BGL was 6.9 h. Following introduction of the standard sliding scale there were nine patients who required insulin infusions during the period of audit. The time taken to initiate therapy was reduced to 0.4 h (P = 0.09) while the time taken to achieve a BGL of <10 mmol litre–1 was reduced to 6 h (P = 0.32). The time between the first and third BGL which provides a useful index of compliance with practice guidelines was reduced to 3 h (P = 0.23).
The use of a standard sliding scale seems to facilitate more expedient control of blood glucose levels and its introduction increased compliance with established practice guidelines. The small sample size does not achieve statistical significance.