Fall 2019 – Developing an Algebraic Formula Predicting Hemodynamic Responses to the Tilt Table Test

The tilt table test is a common clinical test used to evaluate systemic blood pressure homeostasis. The sensitivity of systemic pressure to tilt is modulated by both the baroreflex and mechanical properties of the closed loop system. Inferring the cause of changes in the sensitivity of systemic pressure to tilt angle is not possible from experimental means alone. Investigators have thus used the standard minimal closed-loop model to predict blood pressures with table tilt, but numerical solutions of model equations requires all mechanical parameter values to be known a priori. However, it has been shown that linearizing model equations allows the derivation of algebraic formulas for blood pressure that explicitly relate variables to mechanical parameters without this limitation. Therefore, the purpose of the present work is to derive an algebraic formula for the sensitivity of systemic pressure to tilt in terms of the mechanical properties of the closed-loop system. The construction of a working model has been fulfilled and the current aim involves integrating supplemental revisions in the interest of developing an analytical tool that can be used to guide future clinical research in this area.