Dynamic Changes of Cardiopulmonary-Cerebral Causality during Cardiopulmonary Resuscitation.

Cardiac arrest (CA) has a serious impact on human health. Quality assessment of cardiopulmonary resuscitation (CPR) combined with feedback on physiological parameters is important in improving patients' survival and neurological prognosis after CA. Little is known how the cardiopulmonary-cerebral relationship changes during CPR. This study aimed to investigate the dynamic changes of cardiopulmonary-cerebral causality during CPR. Based on animal experiments, electrocardiography, end-tidal carbon dioxide and electroencephalogram were collected during CPR and were divided into Baseline, CA, CPR and recovery of spontaneous circulation (ROSC) periods. In this study, convergent cross-mapping (CCM) was used to examine dynamic changes of cardiopulmonary-cerebral causality during CPR. Among the five brain regions, temporal region was most closely connected to other brain regions, so it was selected the representative brain region for cardiopulmonary-cerebral CCM analysis. The results showed that heart-to-lung, brain-to-lung causality existed in all periods. No causal relationship was found between the heart and brain, lung-to-heart, brain-to-lung in all periods. The strength of heart-to-lung and brain-to-lung causal effects decreased significantly at CA and increased significantly at CPR and ROSC (p < 0.05). Results showed that the causal effect strengths of cardiopulmonary-cerebral system are very sensitive to changes in the physiological state of CA patients, providing a new way to assess the effectiveness of CPR.Clinical Relevance- This study confirmed that the causal effect strengths of cardiopulmonary-cerebral system are very sensitive to changes in the physiological state of CA patients. It helps to gain a deeper understanding of coupling relationships between cardiopulmonary-cerebral system during CPR, providing a new approach for evaluating the effectiveness of CPR.