Interwoven is partnering with TKDG and Nuwellis to create a wearable solution to aid patients while undergoing Aquapheresis therapy. For patients suffering from Congestive Heart Failure (CHF), fluid overload is a dangerous condition. If your heart is weakened by heart failure, your kidneys may not get enough blood to work as well as they should. As a result, your body retains salt and water in a misguided attempt to boost your blood volume. Aquapheresis therapy uses ultrafiltration to remove the excess fluid.
Wearable Medical Device for Aquapheresis Therapy
What we did
- Design Research
- Concept Development
- Ideation and sketches
- Form Exploration
- Prototyping
- Medical Testing
Clients / Collaborators
Product Description
This project focused on improving catheter protection and vein access for patients undergoing fluid management therapy due to Congestive Heart Failure (CHF). The goal was to develop an external arm stabilization and protection device that minimizes the risk of catheter dislodgement, vein compression, and patient interference—while accommodating various patient anatomies, treatment postures, and ambulation levels. The resulting design explores modular physical prototypes that provide targeted support, restraint, and protection to optimize catheter performance across clinical settings.
Design Process
Our work began with deep user research, clinical collaboration, and biomechanical analysis. We identified several critical challenges: improper arm positioning could constrict blood flow, full elbow flexion threatened catheter stability, and patients often interfered with the catheter—consciously or unconsciously. These insights led to a focused exploration of structural and wearable concepts that promote safe positioning, reduce vein compression, and protect the catheter entry point.
We created eight functional concept prototypes—including inflatable sleeves, rigid cuffs, foam bridges, and angled supports—each mapped to a specific clinical insight such as elbow extension, arm elevation, or compression protection. We selected Baymedix® froth foams as the core material for their softness, moldability, and ability to manage moisture and pressure comfortably against the skin.
Testing & Validation
Following early feedback from physicians at the NYC VA Hospital, we refined and iterated several
concepts based on usability, comfort, and clinical viability. Prototypes were evaluated for ease of
application, patient variability, and compatibility with real-world hospital protocols. Notably, the
Foam Bridge and Angled Support earned strong clinician interest for their protection without
restricting patient mobility.
To further validate our design assumptions, we conducted a comprehensive ultrasound study,
analyzing venous blood flow under different resting postures and prototype configurations. This
included comparative testing at multiple arm positions and vein locations (from cubital fossa to
subclavian vein) with and without external compression. The results directly informed the next
stage of development, helping us define design parameters that preserve venous flow, reduce
insertion risks, and enhance catheter performance.
Aquapheresis therapy, delivered by the Aquadex FlexFlow® System, uses a simplified approach to ultrafiltration for the removal of salt and water in patients with hypervolemia, or fluid overload.
Effective treatment for fluid overload
Aquapheresis is a medical therapy designed to remove excess salt and water from the body safely, predictably, and effectively from patients suffering from fluid overload for whom diuretics have failed.
Aquapheresis therapy, delivered by the Aquadex FlexFlow® System, uses a simplified approach to ultrafiltration for the removal of salt and water in patients with hypervolemia, or fluid overload.
Interwoven Partners with Tanaka Kapec
Rebeccah Pailes-Friedman, an expert in wearable technology and Jeffrey Kapec founder of Tanaka Kapec Design Group, have combined forces to form a world class and award winning industrial design team that represents over 70 years of innovative product design experience in both wearable products and medical instruments. Together they are working with CHF Solutions, a global leader predicting, measuring, and optimizing fluid balance with their Aquadex FlexFlow® System and patented ultrafiltration Blood Circuit.
