Sterilise

Sterilise is a surgical instrument sterilisation tray designed for Auckland Hospital. It is designed to reduce the risk of causing tears in sterile wrap while balancing the contradictory needs of washing and sterilisation processes.

At Auckland Hospital, surgical instruments are placed in stainless steel trays and wrapped in a sterile material called Kimguard before being put through an autoclave for sterilisation.

It is vital that the Kimguard remains in tact from the time of wrapping until the tray is opened for use during surgery. During this time, wrapped trays are stored on metal shelving, put through the autoclave, then transported to the operating room on a case cart. 

At each stage of this process tears in the Kimguard wrap may be caused by sharp edges on the surface of the sterilisation tray, friction around the tray's feet, and pressure from heavy surgical instruments. Even the slightest tear in the wrap can compromise sterility requiring surgeries to be postponed and instruments re-sterilised. 

In response to this problem, I worked closely with staff from Auckland Hospital's sterilisation department to develop a sterilisation tray design that would significantly reduce the risk of tears and their costly consequences.

The design can be cut and folded from a single sheet of stainless steel allowing for a smooth external surface. Rather than including separate feet that might create unwanted pressure points, pressure is distributed evenly across the tray's perimeter, while the raised centre area allows liquid to drain away during washing, and steam to evaporate during autoclave sterilisation.

In place of welded corners, which are often the cause of tears in the Kimguard wrap, smooth corner pieces clip into the stainless steel base. The corner pieces are injection molded from a recyclable, autoclave-safe, and alkali-resistant plastic called Radel R. 

Handles for lifting and transporting the tray are attached by a flange incorporated into the sheet metal form. With a right-angle profile, the handles sit inside the tray during wrapping and sterilisation while remaining elevated above the tray contents so staff can grasp them without touching the surgical instruments.