Abstract—In this paper, study is focused on patients with autonomic dysfunction, such as Parkinson's disease, and how the interaction between cerebral autoregulation and ventilatory control is affected under hyperventilation and posture changes. Experiments were designed with 13 healthy youth subjects, 10 healthy elder subjects, and 13 subjects with Parkinson's disease (PD) to acquire cardiovascular and respiratory signals during supine, head-up tilt (HUT), and hypocapnia. Signal processing is performed to obtain the end-tidal partial pressure of carbon dioxide (P_ETCO2) throughout the hypocapnic range and their corresponding cardiovascular and respiratory signals, including mean systolic blood pressure (MSBP), mean arterial blood pressure (MABP), mean heart rate (MHR), mean breathing rate (MBR), and mean cerebral blood flow velocity (MCBFV). Analysis was further achieved to study the variations in parameters to changes in P_ETCO2 and to depict their variation over time. The results of the different analysis all pointed to suggesting that although Parkinson’s patients still retain some form of cerebral auto-regulation, they do not have the range of blood flow regulation that a healthy subject does and reactivity to CO₂ is limited to a smaller range.

Index Terms—autonomic dysfunction, Parkinson's disease, hyperventilation, posture changes, cerebral blood flow

Cite: Shyan-Lung Lin, Andy Ying-Chi Liao, and Shoou-Jeng Yeh, "The Cardiovascular and Respiratory Responses to CO₂ under Hyperventilation and Posture Change in Parkinson’s Patients," Journal of Medical and Bioengineering, Vol. 4, No. 5, pp. 350-356, October 2015. Doi: 10.12720/jomb.4.5.350-356