Abbreviations: (ICU) intensive care unit, (PE) polyethylene, (TGC) tight glycemic controlKeywords: blood glucose, critically ill, insulin, tight glycemic control We aimed to explore the impact of insulin adsorption onto infusion sets in the laboratory and to assess retrospectively if higher insulin doses are required after syringe changes in practice in the ICU. �dsorption is reported to occur �dsorption is reported to occur predominantly during the first hour of infusion, after which binding sites are saturated. 5 There is greater insulin recovery with faster flow rates and higher insulin concentration. 6 The clinical significance of such adsorption in the ICU setting is uncertain. 5In our study-approved by the local ethics committee-adsorption of insulin onto the giving sets used in our adult of insulin onto the giving sets used in our adult ICU was analyzed. The infusion set used was a 5�� ml polypropylene syringe (BD PlastipakThe infusion set used was a 5�� ml polypropylene syringe (BD Plastipak ® ) and 1.6 ml/2���� cm polyethylene (PE) tubing (Cardinal Health, extension set). In the laboratory, the concentration investigated was 1 U/ml (PE) tubing (Cardinal Health, extension set). In the laboratory, the concentration investigated was 1 U/ml In the laboratory, the concentration investigated was 1 U/ml of neutral insulin in sodium chloride ��.9%. The concentrations were determined using a high�performance liquidThe concentrations were determined using a high�performance liquid high�performance liquid chromatography method with a Jupitor 3����, 5 method with a Jupitor 3����, 5 with a Jupitor 3����, 5 μm C18, 25�� mm x 4.6 mm column (Phenomenex), a mobile phase of ), a mobile phase of , a mobile phase of 30% acetonitrile and 0.1% TFA in water, and ultraviolet detection at �10 nm. �ignificant insulin adsorption of 10% ultraviolet detection at �10 nm. �ignificant insulin adsorption of 10% �ignificant insulin adsorption of 10% �ignificant insulin adsorption of 10% occurred during the first hour of an infusion when the infusion rate was 1 ml�h ( of an infusion when the infusion rate was 1 ml/h ( of an infusion when the infusion rate was 1 ml/h (Figure 1). Our experience suggests that this is a common infusion rate used in intensive insulin therapy. �o significant adsorption occurred when the infusion �o significant adsorption occurred when the infusion rate was 4 ml/h, although a trend could be seen with solution leaving the PE tubing at the beginning of the time period having a lower insulin concentration, which increased with time.The infusion rates used before and after an infusion set change were investigated for 1�� ICU patients known to were investigated for 1�� ICU patients known to have been managed with a TGC protocol, aiming for glycemia of 4.4-6.1 mmol/liter, to examine any relationship between the duration of usage of the infusion set and the variation in insulin dosing required. These patients were . These patients were not prescribed drugs known to affect glucose control, such as inotropes and corti...