In 2009, specific peri-operative glucose management guidelines were introduced for cardiothoracic patients. Evidence from the literature showed that reducing hyperglycaemia improved outcomes1, 2, however tight glycaemic control was associated with increased mortality3. Our guidelines aimed for blood glucose levels (BGL) between 5-10mmol/L and advocated use of a continuous insulin infusion (CII) when BGL>10mmol/L.
To retrospectively analyse glucose data and insulin infusion usage, pre- and post-institution of peri-operative glucose management guidelines.
Intra-operative and intensive care data was collected retrospectively on consecutive cardiothoracic patients over 3 months in 2004, prior to instituting our guidelines. Similar data was collected for 3 months in 2010, after guideline introduction.
114 patient records were analysed in 2004 and 129 records in 2010. The groups were similar at baseline, except for a lower median HbA1c in the post-guideline group compared to pre-guideline (6.6% versus 7.5%). Overall median BGL was similar pre-guideline (8.4mmol/l) and post-guideline (8.3mmol/l). The percentage of BGL above target (> 10mmol/l) was 22.2% post-guideline compared to 25% pre-guideline and the within target BGL (5-10mmmol/l) were similar pre- and post-guideline (72.7% versus 74.9%). Severe hypoglycaemia (BGL ≤ 2.2mmol/l) occurred in 1 patient in the post-guideline group (0.8%) and none occurred pre-guideline. BGL were taken more frequently post-guideline intra-operatively (every 37.5 minutes versus 65.8 minutes) and in ICU (readings every 2.3 hours versus 2.7 hours). Pre-guideline, there were 6 patients intra-operatively where BGLs were not recorded, compared to none post-guidelines. CII was commenced more often intra-operatively post-guideline than pre-guideline [32% versus 13.2%], but CII usage was similar in ICU pre-and post-guidelines (46% versus 48.1%).
Introduction of peri-operative glucose management guidelines for cardiothoracic patients improved aspects of glycaemic management with more frequent BGL recorded, less BGL above target and higher insulin infusion usage intra-operatively, without a change in severe hypoglycaemia.