Open-loop glucose control: Automatic IOB-based Super-Bolus feature for commercial insulin pumps

ROSALES, NICOLÁS; DE BATTISTA, HERNÁN; VEHÍ, JOSEP; GARELLI, FABRICIO

COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE

ELSEVIER IRELAND LTD

Año: 2018

0169-2607

Background and Objective: Although there has been significant progress towards closed-loop type 1 diabetes mellitus (T1DM) treatments, the entirepopulation of diabetic patients still treat the illness in an open-loop manner(based on basal and bolus insulin infusion), suffering from meals mismanaging. This paper presents a method for automatic insulin bolus shapingbased on residual insulin or insulin-on-board (IOB) as an extra feature forcommercial insulin pumps.Methods: This methodology allows the pump to generate the so-called superbolus (SB) for the compensation of high glycemic index meals employing avalidated two-compartment IOB model. The extra amount of bolus and thebasal cutoff time are computed using the duration of insulin action (DIA),which is a patient parameter well known by the clinicians. In this way, thepump automatically re-establishes basal insulin when IOB reaches its basallevel. Thus, detrimental transients caused by manual or a-priori computations are avoided.Results: The potential of this method, registered on patent and priorityrequests, is illustrated via in-silico trials over a simulation platform basedon the FDA-accepted T1DM UVA/Padova virtual patients, including a library of mixed meals and intra-patient variability. A reduction of the timein hyper and hypoglycemia was obtained with the proposed automatic SBwith respect to standard treatment for a cohort of 30 patients facing a highglycemic index mixed meal of 25g, a mixed meal of 50g, and a 75g and 100gof CHO meal. A 10 adult cohort has been simulated under intra-patientvariability and a mixed meal scenario for the evaluation of the algorithmEmail address: nicolas.rosales@ing.unlp.edu.ar (Nicol´as Rosales)Preprint submitted to Elsevier April 24, 2017under realistic circumstances. The glucose excursion was reduced by theautomatic SB, diminishing the postprandial peak and reaching a higher latepostprandial glucose levels.Conclusions: A novel algorithm for open-loop treatment was introduced,based on the super bolus treatment and the IOB profile of the patient. Thisalgorithm can be easily loaded into any medical device software and dependsonly on the DIA of the patients, thus giving rise to a new alternative forfinal users of currently approved insulin pumps. The results show that better performance is achieved with the same amount of administered insulinas the standard treatment for high glycemic index meals.