Thomas Dick, Ph.D.
Department of Medicine
Case Western Reserve University
“Effects of Brainstem Inflammation on Cardio-Respiratory Patterning”
Heart Rate Variability (HRV) refers simply to the variation in the cardiac rhythm and has had varied success as a biomarker. Cardio-respiratory coupling modulates HRV and neural forces couple cardiac rhythm to breathing. In this vein, we (I & my colleagues at CWRU) have been interested in understanding neural mechanisms which modulate the strength of cardiorespiratory coupling and ventilatory pattern variability. My talk will delve into ‘what it means that neuro-physiologic mechanisms modulate the variability of biologic rhythms’. Fundamental ideas regarding variability are: 1) variability results from random and deterministic influences, 2) decreases but also increases in variability may be associated with pathophysiology and 3) variability may be a spice in, for, and of life. The driving force of this research is the plausibility that complementary measures variability calculated in real time can serve as a biomarker tracking disease processes and treatment effectiveness. As a model disease, I have chosen sepsis not only because the onset of sepsis is hard to recognize and treatment should begin as quickly as possible after it’s recognized but also brainstem inflammation, which occurs in sepsis may have a critical roles in uncoupling cardiorespiratory neural control systems and in the losses of organ and inflammatory control causing a devastating downward spiral to multiple organ dysfunction syndrome. I will show 1) how we measure variability, 2) changes in the variability of a central pattern generated in the absence of variability in sensory input, 3) central micro-injections of cytokine in the absence of peripheral tissue damage or infection replicates changes in variability and 4) how treatment of central inflammation attenuates changes in variability of biologic rhythms. This basic neurophysiologic research has direct insight in the mechanisms of variation in patients’ and people’s rhythms.
Friday, March 23, 2018, 11:00AM-12:00PM, LIB-110
University of North Texas Health Science Center
Fort Worth, Texas