​Typenex finalcheck blood bag lock

Typenex Medical in Chicago collaborated with Design Integrity to develop a low cost combination lock that would significantly reduce the possibility of errors during blood transfusions. This medical device product development project was taken through to production in a rapid time frame to capitalize on the market opportunity.


Typenex retained Design Integrity to design and develop a blood transfusion bag lock that would ensure that each bag would be used for the right patient in the hospital. The lock had to be secure, and it had to be manufactured at a low cost.



The Design Integrity engineering and industrial design team collaborated with Typenex in the development of the FinalCheck transfusion bag lock. The device was made with injection molded plastic parts, and it was designed for high volume manufacturing.

The practitioner sets each single-use combination lock with a patient-specific four-digit code and then secures the blood transfusion bag with the lock. Once the lock is attached to the bag, only the four-digit code on the patient’s wristband will open the lock and allow access to the blood unit in the bag.


Client Benefit

The FinalCheck lock, when used with the Typenex FinalCheck verification system, virtually eliminates patient matchup errors. If a healthcare clinician accidentally attempts to open the bag using another patient’s code, the lock will stay closed and a transfusion error is prevented. The lock has been a success in the marketplace, and the design met all functional product requirements.

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