Exploring the Use of Variable Rate Intravenous Insulin Infusion in Hospital: A Hierarchical Task Analysis
Authors: Iflaifel M , Lim R H M , Crowley C , Greco F , Iedema R 
Published: March 2021

Abstract

Introduction
Variable rate intravenous insulin infusion (VRIII) is a cornerstone treatment for controlling elevated blood glucose (BG) in inpatients who are missing meals, and/or have a critical illness. VRIII can cause serious harm to patients if used incorrectly. Traditional approaches to improving safety have focused on identifying errors, then finding solutions to prevent future recurrence. Such approaches fail to fully take into account the complex adaptive nature of healthcare systems, which cannot be controlled solely by standards or procedures. The Resilient Health Care (RHC) approach proposes that understanding the variability in healthcare practitioners’ everyday work e.g. a physical and cognitive activity directed toward achieving a specific goal, is key to enhancing patient safety (1). There are a considerable number of studies on using RHC to enhance safety, however, no studies to date have researched resilience in the use of VRIII.

Aim
This study sought to comprehensively understand, within a RHC framework, how VRIIIs are used in the clinical environment.

Methods
A qualitative observational study was conducted in a Vascular Surgery Unit. A purposive sample of two inpatients and all healthcare practitioners caring for VRIII aspects for these patients were recruited. The researcher video-recorded healthcare practitioners while prescribing, administering and monitoring VRIII. The video data were then transcribed and inductively coded to construct a deep understanding of the use of VRIII. A hierarchical task analysis (HTA) which is a core human factors approach (2) was used to represent the actual task for the use of VRIII.

Results
Twenty-two hours of video recordings of 10 healthcare practitioners were used to develop the final HTA with a top-level goal of controlling elevated BG using VRIII. The HTA clearly illustrated the complexity of using VRIIIs by highlighting more than 100 practical activities to achieve the goal. The observed challenges were mainly related to lack of knowledge e.g. the co-prescription of appropriate concurrent IV fluids, and system and technology problems e.g. the need for frequent BG monitoring. The analysis of the video data identified various strategies that healthcare practitioners used to respond to variability in work including knowledge, standardising practice e.g. the using of ready-to administer insulin infusions, and context-dependent adaptations including asking available colleagues to countersign administration and assigning the monitoring task to other staff when the nurses were busy. Most of the observed adaptations had positive outcomes in terms of patient care delivery.

Conclusion
This study was the first to have explored how ‘work is done’ in reference to the use of VRIII using HTA. The study was limited by time, the Covid-19 pandemic and number of participants. However, the developed HTA provided detailed tasks and, by highlighting when and how adaptations were used, systematically presented the process as it was actually done. Future work will focus on using the data from this study to model RHC in the use of VRIII in a way that allows the study site to better enhance patient safety.

References
1. Hollnagel E, Braithwaite J, Wears R. Delivering Resilient Health Care. Abingdon, Oxon: Routledge 2019.
2. Stanton NA, Salmon PM, Rafferty LA, et al. Human Factors Methods: A Practical Guide for Engineering and Design. 2nd ed. England: Ashgate 2013.