Abstract: SA-PO968
Relationship Between Central Venous Catheter Protein Adsorption and Water Infused Surface Protection Mechanisms
Session Information
- Dialysis: Vascular Access - II
October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Dialysis
- 704 Dialysis: Vascular Access
Authors
- Sutherland, David W., Boston University, Cambridge, Massachusetts, United States
- Charest, Joseph L., Draper Laboratory, Cambridge, Massachusetts, United States
Background
Many dialysis patients are implanted with central venous catheters (CVCs) despite increased patient risk due to thrombosis and biofilm formation. These complications are caused by fibrin sheath formation, which is initiated by blood protein adsorption upon exposure. Current solutions to prevent thrombotic occlusion and biofilm formation remain ineffective at preventing these failure modes and remediation treatment options are limited and often harmful. We propose an active method to reduce protein adsorption and effectively disrupt adherent protein sheaths, water infused surface protection (WISP).
Methods
Experiments were performed in vitro using a modeled CVC that simulated the WISP mechanism. A hollow fiber membrane (HFM), representing the CVC lumen, was mounted in a concentric chamber. The WISP was achieved by pressurizing the concentric chamber with saline while blood flowed through the HFM, causing a continuous saline infusion across the HFM wall. The resulting water boundary layer at the lumen surface limited the blood contact with the HFM wall resulting in decreased protein adsorption.
Results
Analytic lubrication models matched our experimental pressure measurements suggesting the WISP created a blood-free boundary layer on the HFM surface. Figure 1 shows the WISP boundary layer reduced the average density of adsorbed protein on the model CVC with increasing WISP flowrates, up to 96.4% over the 0% WISP condition (* denotes P≤0.016, 2-way ANOVA). Additionally, the WISP CVC displayed the ability to reduce previously-adsorbed protein films, and deliver chemical agents, such as heparin, within the WISP flow.
Conclusion
The proposed WISP technology has functionality that could reduce failure incidence to improve clinical outcomes. WISP shows the ability to significantly reduce protein adsorption, as well as presents a new methodology to treat major CVC complications; removing pre-adsorbed material or treating a resulting infection by more effectively delivering drugs to the point of adhesion.
Funding
- Commercial Support – The Charles Stark Draper Laboratory