Honorable Mention: Preventing Microbubble Complications in Hemodialysis Patients

Bubble traps currently used in hemodialysis treatment are designed to protect against millimeter-sized air bubbles from entering the patients' blood circulation, but many autopsy reports demonstrate the presence of air microemboli of the heart, lungs, and brain in chronic hemodialysis patients. Recent in vitro studies using Doppler Ultrasound have confirmed the emergence of air microbubbles passing the security system of the hemodialysis circuit without triggering the alarm. A small quantity of microbubbles may be clinically silent and apparently harmless, but the chronic and recurrent exposure to microbubbles has a cumulative effect on these patients, leading to increased disability and poorer quality of life. Proposed herein is a device to prevent bubbles of all sizes from entering the patients' blood circulation during hemodialysis treatment. At the moment, there is no known treatment for chronic exposure to microbubbles; thus prevention is the only viable solution.

In this solution, a de-bubbling device replaces the current air traps on the hemodialysis circuit and would remove air bubbles of micrometer- to millimeter-size. The device works by employing low centrifugal and gravitational acceleration effects to create a micrometer-thin film of blood flow, exposing all bubbles to the blood surface for de-bubbling in a low vacuum environment. The proposed device would be rotated at slow speed and partial pressure would be maintained at minimum levels to reduce blood cell trauma. Because this device is incorporate into existing hemodialysis circuits, startup expenses are reduced. Engineering models have demonstrated feasibility of this design, preparing if for prototyping and use in animal models.