The use of continuous subcutaneous insulin infusion (CSII) pumps has been gaining popularity since 1979, when the first research report on insulin pumps was published. Insulin pumps-small medical devices that are programmed to infuse insulin through a catheter placed under the skin-are a replacement for multiple daily injections of insulin. They are currently being used by 375,000 people with type 1 diabetes, many of whom prefer CSII to multiple daily injections because of the increased flexibility of diet and exercise, increased convenience and precision when dosing, and better predictability of blood glucose levels that insulin pumps can provide when used correctly. Recent pump manufacturers have engineered a new feature called a bolus calculator, which calculates bolus insulin doses based on input from the pump wearer, which functions to help patients obtain optimum control over blood glucose levels. The bolus calculator takes into account the patient's current blood glucose, target blood glucose, amount of carbohydrate consumed, and other factors such as insulin sensitivity and insulin-to-carbohydrate ratio as well as duration of insulin action ("insulin on board"). Each pump company calculates insulin doses in a slightly different way. This article will review differences in bolus calculator recommendations between four insulin pumps, as well as errors that may occur when using bolus calculators. It will also include an in silico simulation of a meal followed by a snack using multiple insulin decay curves.

Cleared BGMs do not always meet the level of analytical accuracy currently required for regulatory clearance. This information could assist patients, professionals, and payers in choosing products and regulators in evaluating postclearance performance.

We conclude that CLC technology has matured and is safe for prolonged use in patients' natural environment. Based on these promising results, a large randomized trial is warranted to assess long-term CLC efficacy and safety.

A one-time algorithmic adjustment of open-loop settings did not alter glucose control in a relatively short duration outpatient closed-loop study. The CLC system proved very robust and adaptable, with minimal (<2%) time spent in the hypoglycemic range in either arm.

OBJECTIVETo evaluate two widely used control algorithms for an artificial pancreas (AP) under nonideal but comparable clinical conditions.RESEARCH DESIGN AND METHODSAfter a pilot safety and feasibility study (n = 10), closed-loop control (CLC) was evaluated in a randomized, crossover trial of 20 additional adults with type 1 diabetes. Personalized model predictive control (MPC) and proportional integral derivative (PID) algorithms were compared in supervised 27.5-h CLC sessions. Challenges included overnight control after a 65-g dinner, response to a 50-g breakfast, and response to an unannounced 65-g lunch. Boluses of announced dinner and breakfast meals were given at mealtime. The primary outcome was time in glucose range 70–180 mg/dL.RESULTSMean time in range 70–180 mg/dL was greater for MPC than for PID (74.4 vs. 63.7%, P = 0.020). Mean glucose was also lower for MPC than PID during the entire trial duration (138 vs. 160 mg/dL, P = 0.012) and 5 h after the unannounced 65-g meal (181 vs. 220 mg/dL, P = 0.019). There was no significant difference in time with glucose <70 mg/dL throughout the trial period.CONCLUSIONSThis first comprehensive study to compare MPC and PID control for the AP indicates that MPC performed particularly well, achieving nearly 75% time in the target range, including the unannounced meal. Although both forms of CLC provided safe and effective glucose management, MPC performed as well or better than PID in all metrics.