Using thermochromic ink for medical simulations

Abstract

?? 2017 Alsalemi, Aldisi, Alhomsi, Ahmed, Bensaali, Alinier, Amira, licensee HBKU Press. This is an open access article distributed under the terms of the Creative Commons Attribution license CC BY 4.0, which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited. Alsalemi A, Aldisi M, Alhomsi Y, Ahmed I, Bensaali F, Alinier G, Amira A., 'Using thermochromic ink for medical simulations', Qatar Medical Journal, 4th Annual ELSO-SWAC Conference Proceedings 2017:63 http://dx.doi.org/10.5339/qmj.2017.swacelso.63Background: In medical simulation and training, blood is used to exhibit its different behaviors in context. In some cases, blood color differential is an imperative visual effect to ensure high-fidelity training and practical understanding. High simulation realism is usually achieved by using animal or artificial blood (which mimics some biological features of blood), which has high cost, requires disposable equipment such as oxygenators, and entails contamination or infection risks. Methods: A novel method for blood simulation is introduced. Using the thermal properties of thermochromic ink, its color can be altered by adjustment of temperature. 1 The unique red color of blood can be mimicked to a high fidelity using a custom hue of thermochromic ink. Then, by adjusting its temperature, realistic dark and bright red can be employed to simulate the low and high oxygen concentrations of blood, respectively. Although thermochromic ink currently does not imitate other blood properties such as viscosity and clotting, it has superior merits when color change simulation is a paramount priority. The major advantages of the proposed solution are reusability and cost. Thermochromic ink can be used for multiple simulations without any noticeable change in quality. It also costs significantly less than using actual or artificial blood. Results: Testing results of the proposed solution in extracorporeal membrane oxygenation (ECMO) simulation has proven its efficacy as a practical solution for medical simulations (see Figure 1). To prevent membrane occlusion because of the thermochromic ink, the latter needs to be pierced. In addition to ECMO simulation, other medical applications are being considered. Conclusions: The use of thermochromic ink in medical training provides reproducible color change simulation features of blood while maintaining significantly lower equipment costs and contamination risks as all circuit components can be reused

Using thermochromism to simulate blood oxygenation in extracorporeal membrane oxygenation

“…In this article, we demonstrated the design and implementation of a patented simulated “ECMO circuit” featuring a unique thermochromic effect that resembles blood oxygenation color change in real ECMO circuits. 27 The circuit operates on a balanced and continuous heat exchange process, producing a temperature difference between the drainage and return lines and, hence, a color difference due to thermochromism. It can create visual cues relevant to many emergency scenarios, including oxygenator failure, disconnected gas supply, increased oxygen consumption, decreased lung function, inadequate circuit flow and recirculation.…”

“…Thermochromic inks and powders are products designed to transition between two distinct states (colors) above and below a fixed transition temperature ( T t ). 18 Our simulated ECMO circuit exploits this property by circulating a thermochromic fluid (diluted thermochromic ink mixed with other dyes) through two physically distant modules responsible for adding or withdrawing thermic energy (heat). Heat manipulations drive temperature change in the fluid, triggering it to change state.…”

Addressing the challenges of ECMO simulation

“…Adequate oxygenation observable by blood colour change and line chattering caused by access insufficiency are some of the physically simulated issues relying on additional hardware that is currently partially dissimulated inside the custom-designed patient simulator. 43,44 This simulator requires no specific learner orientation, as it fully replicates an actual ECMO circuit and machine and minimal training for the facilitator operating the instructor application. Although currently modelled around a particular ECMO machine, 3-D printing and reprogramming the console would enable the system to replicate other types of ECMO machines.…”

Extracorporeal membrane oxygenation simulation-based training: methods, drawbacks and a novel solution

“…54,55 The simulator is centered around an “ECMO circuit” module which relies on a thermochromic fluid and continuous temperature adjustment to simulate blood oxygenation and deoxygenation (Figure 4A). 56,57 Instead of a real oxygenator and pump-head, 3D printing was utilized to replicate circuit components used to circulate the thermochromic fluid to maintain circuit continuity (Figure 4C). A line chattering module is hidden under the bedding and connects to the circuit generating chatters in the drainage (Figure 4D).…”