Design of Containment Capsule for Covid-19 Patients Transport

Due to the Covid-19 pandemic that has taken many lives around the world, a lot of projects and initiatives to fight this decease were born. In different countries concepts of capsules to isolate Covid-19 patients to avoid direct contact with the health workers during their transportation in ambulances or other media. To help the health workers to be more safe during the transportation of Covid-19 patients , the Investigation Unit of Mechanical Engineering of the San Carlos University designed a capsule easy to carry to different places (due to the geographic structure in some places), light, corrosion resistant, easy to build with available materials and components and as cheap as possible(to make it possible its mass production if required). The design of a foldable containment capsule was the idea proposed by the Investigation Unit of Mechanical Engineering. In this article is explained the design and the selection of materials to build a containment capsule that will fulfill all the characteristics previously exposed.

The methodology to design the containment capsule was the selection of materials for their mechanical properties an availability in the market, followed by the design of the internal and external structure using 2D and 3D CAD software. To make the capsule as light as possible the material selected to make the structure that will hold the plastic is aluminum. The aluminum is light, has a great corrosion resistance and its strong enough to hold support the plastic [1-5]. This is important because the capsule may be subjected to adverse weather conditions. To isolate the patient as much as possible, the rigid structure is covered in 40-gauge clear polyethylene plastic. This a common plastic that has a lot of applications, and it´s thick enough to separate the patient and the Health Workers. Due to the fact that has a lot of applications it´s easy to find, so its availability is other advantage. Also is a very flexible material and it is performing well at low temperatures. Other factors of the polyethylene are its isolating properties, its odorless character, its resistance to corrosion, its low water-steam transmission, and its price [2,3]. To filter the air that flow in and out of the capsule the decided to use something simple that already exist worldwide. Medical grade filters were chosen to use in the capsule. With this type of filters, the risk of contagion is lower for the health workers involved in the process of covd-19 patient’s transport.

The team designed a foldable capsule design using different diameter aluminum tubes that will slide inside each other. The 3D design of the structure is shown in the Figure 1. The folded structure is shown in the Figure 2. The aluminum structure can be separated in 3 parts, which are shown in Figure 3. The capsule is designed to be attached to a stretcher, for ambulance or other vehicles transport. With straps in the sides to be easily attached and unattached. The final design of the containment capsule is shown in Figure 4.

Figure 1: Rigid structure design.

Figure 2: Folded structure.

Figure 3: Structure divisions.

Figure 4: 3D design of containment capsule.

The service sector-or more precisely, the healthcare sector- is different from industry and from the production line model of Toyota, so the transition is not straightforward. We can always argue that the service sector is different from industry and that hospitals are not factories [7]. By definition, a service is a process that takes place frequently in the customer's presence and does not produce the modification of the physical properties and shape of materials, as opposed to the industrial sector [31], where the product is visible on the production line and is produced in the absence of the client. Although the lean philosophy was developed in manufacturing, Womack & Byrne [25] argue that its application is much broader. Womack & Byrne [25] mentioned that: ‘Lean thinking is not a manufacturing tactic or a cost reduction program, but rather a management strategy that is applicable to all organizations because it has to do with process improvement. All organizations - including health sector organizations-are composed of a series of processes, or sets of actions aimed at creating value for those who use or depend on them (clients/patients).'

A perfect process creates value focused on the patient's needs. It should be noted that from sector to sector things change, and that applying principles and tools in the manufacturing sector is not the same as applying them in the services sector, (i.e., healthcare). Particular attention should be paid to these differences and adaptations should be made in accordance with the characteristics of each context [69]. The root cause of the problems is usually the same for industry and healthcare. Kalong & Yusof [70] found in a literature review that all seven categories of waste in the manufacturing industry also exist in the healthcare industry. Snowball [71] claims that in terms of waste and improved efficiency, the differences between the manufacturing industry and the healthcare industry are minor: just as in the manufacturing industry, healthcare work with lean aims to create better value for the customer. However, Young & McClean [58] argue that the healthcare sector differs from other sectors in that the definitions of ‘customer’ and ‘value’ are more complicated. These concepts need to be clear to determine the steps required in the improvement work. Other major differences are that healthcare is usually not profit-driven and that it is difficult to measure value because the ultimate goal is to cure patients and prevent diseases. Examples of value for the patient can be short waiting times, good service and high quality treatments.

The researcher’s reflection based on literature review is that lean could be described simply as a philosophy that consists of a set of tools and principles to improve the system in a continuous manner with an aim to reach perfection. This method of thinking can function as a framework for the implementation of a programme change within the organisational setting. Lean emphasises on maximising value by minimising waste in energy, time and resources [25]. As a result, lean can create a culture in the healthcare context characterised by an increase in the satisfaction of patients and stakeholders by allowing all areas to eliminate waste and improve service quality [72]. Conducting research with rigorous methodology in the healthcare system is essential, while still acknowledging that there is no agreed-upon definition of lean management [33,73].

The design and selection of materials allow the containment capsule to be valuable option to reduce significantly the risk of contagion in the health workers during the transportation of Covid-19 patients. Due to the mechanical and chemical properties of the materials the capsule will be light, corrosion resistant and rigid. Thanks to the foldable design using the aluminum tubes, the containment capsule will be easy to carry to different places with difficult access.

To the Direction of General Investigation (DIGI) of University of San Carlos of Guatemala for investing in the project. DIGI Agreement number 41-2020.

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