Bridge Design

The CADD-Solis pump is a patient-controlled analgesia (or PCA) pump that lets clinicians and patients administer pain medication within pre-programmed, patient-specific, safe limits. The CADD-Solis System advances "smart" medication delivery; the user interface was designed by Bridge and Smiths Medical to help reduce medication delivery errors.

The medications PCA pumps deliver can harm patients if programming errors are made. CADD-Solis provides a system designed to help reduce these errors. Using software, the hospital builds a library of safe treatment protocols that are downloaded to the pumps.  To program a pump, a user steps through a sequence of three simple questions relating to observable conditions, such as patient age or route of medication delivery. Only a limited set of safe choices are available at each step.  Once a protocol is selected, the user can adjust delivery parameters only within predetermined safe limits.

CADD-Solis demonstrates the value of design research in focusing the team’s design efforts. Insights gained about the system-wide issues faced by stakeholders—from risk managers to floor nurses—enabled Bridge and Smiths Medical to develop a truly innovative approach, designed to help reduce medication delivery errors, ease the burden of set-up for nurses and dosing for patients.

To appreciate the design challenges CADD-Solis has solved, it’s necessary to understand the complex topic of safe pain medication delivery. After their invention in the 1970s, PCA pumps gradually became more sophisticated in their programming of doses and limits. Multiple routes of administration were developed (intravenous, epidural, and peripheral nerve block), and the number of available drugs and concentrations proliferated.  By the early 2000’s, regulatory groups such as JCAHO (the US Hospital auditing body) and watchdog organizations such as ISMP (Institute for Safe Medical Practices) noted a significant number of safety incidents with PCA pumps. They identified a set of contributing factors, which included many relating to the design and programming of the pumps. These included drug labeling and concentration mix-ups, pump mis-programming, incorrect route of delivery (a safe dose intravenously can be fatal epidurally), incorrect transcription of prescriptions into pharmacy computers, and calculation errors when determining the patient's dose or rate of infusion.

From these safety reviews and the information gathered from the stakeholders--including pharmacists, hospital administrators, pain doctors and nurses, and ward nurses--it was clear that to improve safety, the whole system would have to be tackled. How can the pump that is just on the delivery end achieve this? The design solution was to treat the pump and its programming as just one piece of a medication error reduction system and create a new systematic approach to PCA medication safety.

In addition to the medication delivery system overhaul, Bridge made key design improvements from the prior generation, such as:

• An improved remote dose cord ergonomically designed to sit much more comfortably in the hand of a potentially sleepy patient. It also offers greater ease-of-use for those patients who cannot comfortably use their hands. (See Exhibits yy and zz.)
• A medication cassette which can now be changed using only one hand, instead of two hands as was previously required. (See video.)

CADD-Solis also has built-in USB and infrared ports. As the number of hospitals using more advanced information systems grows, the company will be able to offer appropriate server-based software to connect CADD-Solis to these systems.