Usability & Medical Devices

Modo Inc.
6 min readNov 4, 2020


Usability is about how people understand and use things. The basic idea is simple: every action should produce a desired result. Usability is that simple.

Usability delivers results with no wasted effort which brings us to the world of medical carts. Medical carts provide an easy and accessible example of how usability works.

We live in a mobile world where everything in a hospital moves. Everything. People, food, bedding and technology all move on wheels. Rooms are constantly reconfigured. Patient and families come and go. Hospital architecture is fluid with the last 5% of any structure being a fleet of tiny buildings on wheels transporting everything from salmon to surgical robots.

Medical carts are necessary and useful but overlooked and unloved. Because they are background products, they provide fertile ground for innovation and refinement. If the goal of good design is to fill a need by helping someone get something done, medical carts are a great place to start.

Let’s walk through the forgotten world of medical carts to understand how small things and passionate people can make life better for all of us. Along the way we will pick up usability insights you can use to improve anything from a blender to a mobile app.

Here are ten principles to guide you and your team through the design of products, experiences and medical carts;

1) Intuitive

Make it easy to see what needs to be done. You should not have to remember anything to accomplish a task. Adjustments should be quick and easy. Handles should be where they are expected and supplies should be where they are needed. Keep it simple to make it effective.

2) Familiar

Design should relate to the world we live in. Place frequently used things higher because no one likes bending. Keep storage easy to reach and large enough to hold what you need.

Try to avoid specific storage. Welch Allyn, a monitoring company, uses a wire bracket for CaviWipes but not all disinfectant wipes fit the bracket. When the bracket is empty, users feel something is missing. Why design something that makes nurses question themselves?

3) Control

Let people design the last 10% of any solution. Barcode scanners should be positionable left or right. Cables should easily wrap around handles or hooks. Give your user the freedom to author their own work flow. When a user adapts a cart to their preferences, it changes their emotional relationship to their work and to your brand. Design to put people in control of their lives and their work. They will love you for it.

Philips tooled a tight pocket for a Sony printer on an ultrasound cart. When Sony changed the size of the printer, users were stuck. Give your users the freedom to adapt to change.

4) Ritual

Healthcare is full of work flow rituals like EKG carts needing two handles. Nurses push EKG carts to elevators from the rear. Then, they walk around the cart and use the front handle to politely pull the cart into a crowded elevator. This means EKG carts need two handles.

It is important to understand, document and accommodate rituals that matter. There are no standards. Every procedure and every user group has its own, unstated rituals. Take the time to understand them.

GE Healthcare failed to understand the importance of ultrasound bases as footrests and was surprised when their Venue systems were returned with stress marks from foot placement.

Understand your user.

5) Minimal

The easiest way to reduce errors is to prevent distraction. When it makes sense, route cables internally and conceal fasteners to reduce visual clutter. It helps to remember every extra part, cable or fastener competes for the attention of a nurse.

There is a balance for every system and every procedure. Search for it. In pursuit of cost control, Philips eliminated brakes on the casters of its EKG cart. Several months later Philip’s service department received a request for casters with brakes from Princess Cruise Lines which had been lashing Philips EKG carts to rails in the sick bay of a cruise ship.

Be careful, minimal design cuts two ways. There are limits.

6) Efficient

Observing is more important than asking. Look for accelerators — small details that let experienced users go faster. Design handles to also work as cable wraps.

Erbe Medical made an electrosurgery cart with an angled top to prevent nurses from using the top of a medical device as a work surface. Watch a nurse look for space in a crowded operating room and you will understand why nurses want every surface to be usable. In celebrating its technology, Erbe frustrated the nurses who use their products.

Understand your products have more than one use model. A nurse will thank you for it.

7) Inform

Your design should explain itself. You should be able to use your cart without instructions. When instructions are needed, they should be short, clear and specific. Once you have them, make them visible and easy to find.

Quick reference guides give users an easy way to promote consistent use and reduce technology fatigue. Anticipate the need for a quick reference guide and give your user a visible place to hang it.

8) Emotion

Healthcare is emotional. Everything is.

Nurses and families have feelings about carts and devices. Will this be hard to use? Will this hurt or help? How well will this work? Carts are signaling objects. Your cart does more than perform a task, it evokes an emotion. For patients and caregivers, carts signal the quality of care delivered.

Aesthetics are functional.

Lighter colors show surfaces that need to be cleaned. Soft edges are more approachable. Wire baskets are visually busy and hard to clean. We added personality to Steelcase’s Pocket line of carts by making sure their magnetic barcode holders were perfectly sized to hold a Starbucks coffee cup. Nurses love this simple, human detail.

At some point, a patient will be alone in a room with your device and your cart. Ask yourself, will they be frightened or reassured?

9) Flow

Cognitive flow is the experience of accomplishing something meaningful with a high level of engagement. It happens when you are focused, in control and merging action and awareness. Flow is what designers strive to help you achieve. To experience flow, actions have to fit within capabilities and distractions have to be kept to a minimum. There should be no unnecessary adjustments and no pause points. Declutter everything.

From operating rooms to patient bedsides, the objective is the same: design to invite focus and encourage flow.

10) Access

Accessibility is the right thing to do. It is your chance to make someone’s life better. Making every action accessible makes life easier.

Everything should be open and available. There should be no moments of hesitation. You should not have to open a door to find what you need.

We designed an infusion workstation for ICU Medical that included concealed cables for a sleek, modern look. In clinical testing, we saw nurses struggle with the cables during quick pump exchanges. We replaced internal cable routing with exposed cable guides. We gave up elegance for access to create a design nurses love.

Access sends a message about who you are. Nurses want to work with people and companies who take time to get the little things right.

Access builds trust.

Every action should produce a desired result. Usability is that simple. Now, you have what you need to get started.

Enjoy the journey.

Fabian Schroeder & Bob MarchantModo

Sources and further reading:

1- Usability: The New Dimension of Product Design, Artemis March, Harvard Business Review

2- Usability 101: Introduction to Usability, Jakob Nielsen

3- Design Principles, MIT

4- Ten Principles for Good Design, Dieter Rams