Krystal Jiang
Pronouns: she/her
Research Mentor(s): Alvaro Rojas-Peña
Research Mentor School/College/Department: Department of Surgery-Transplantation / Medicine
Program: UROP
Session: Session 1 (9:00am – 9:50am)
Authors: Krystal Jiang, Sebastian Sewera, Vikramjit Chakrabortty, Kristopher Urrea, Anish Virdi, Brianna Spencer, Spencer Wilhelm, Robert H. Bartlett, Daniel Drake, Alvaro Rojas-Pena
Abstract
Cold storage for up to 6 hours is the standard method for transplant heart preservation. Normothermic ex-vivo preservation using an extracorporeal circuit has been used to maintain hearts in an environment close to normal physiology that allows for prolonged (24 hour) heart perfusion. Bacterial contamination has complicated prolonged ex-vivo heart perfusion (EVHP) and may contribute to tissue damage, leading to heart inviability. This study aims to attenuate the bacterial growth over a 24 hour EVHP experiment. Hearts (n=5) from juvenile pigs were procured using standard protocols and connected to an EVHP circuit. Continuous hemodynamics were monitored and recorded as well as hourly arterial and venous blood gases. Three control EVHP hearts had significantly elevated bacterial colony forming units (>10,000 CFU). Two intervention EVHP experiments were performed by reducing blood draws to every six hours (decreased direct circuit contact via external contamination). However, an equivalent bacterial load persisted in the circuit for both groups. Given that donor blood and heart surface cell cultures were sterile, potential contaminants include: circuit exposure to the external environment, infected post-processing perfusion blood, and/or human contact. These results are the first to conclusively demonstrate infection as a potential cause of early EVHP failure. Future interventions include: complete sterile circuit preparation, increased antibiotic administration, and hypothermia to decrease bacterial colonization. This is an important step towards improving prolonged EVHP, which may increase heart donor utilization for human patients.
