INS and Hyperglycemia: Although currently not approved as a blood glucose reference for insulin dosing, the accuracy and reliability of enzyme glucose sensors continues to improve.58,69 Large positive sensor deviations from the true glucose value increase the risk of hypoglycemia, whereas sensor under readings increase the risk of hyperglycemia, because of inappropriate insulin delivery.8,70 In addition, glucagon was less effective in the prevention of hypoglycemia when delivery was delayed because of positive sensor deviations in a bi-hormonal artificial pancreas study.13