Evaluation of alternative ventilation strategies during cardiopulmonary resuscitation for end organ damage in large animal models

• Applicant: Dr. Miriam Julia Renz
• Subject Area: Anaesthesiology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 545518197

Although survival rates after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) have increased in recent years, the rate of those who regain return of spontaneous circulation (ROSC) remains low. Further research is needed to improve ROSC rates and optimize patient outcomes. This includes optimized ventilation during CPR. The optimal ventilation strategy during CPR is subject of current research. European and American guidelines only recommend securing the airway and then using a ventilation frequency of 10 breaths per minute. Various ventilation approaches have been investigated in the past, including experimental approaches such as chest compression synchronized ventilation (CCSV) and ultralow tidal volume ventilation (ULTVV). Positive endexspiratory pressure (PEEP) as part of ventilation during CPR could improve gas exchange. A pilot study conducted in our working group showed significantly higher partial pressure of oxygen and optimized ventilation pressures when using PEEP. This observation fits into the concept of lung-protective ventilation. Additionally, the use of higher PEEP levels showed no negative influence on hemodynamics. Hemodynamics and gas exchange during CPR influence the patient's neurological outcome. Post-cardiac arrest brain injury (PCABI) is the leading cause of death after CA. Less than half of patients discharged alive from the hospital have good neurological outcome. Hypoxic ischemic brain injury (HIBI) - a part of PCABI - particularly affects hypoxia-sensitive areas of the brain. There is little data on PCABI and HIBI in the porcine model. Our working group formulated criteria to identify and quantify HIBI in the porcine brain in order to be able to quantify the extent of HIBI after CPR and the use of alternative ventilation strategies in the future. The planned project is an - already approved - follow-up trial based on a successful pilot trial on the use of PEEP in alternative ventilation strategies under CPR. The planned project is intended to investigate the benefits of the usage of PEEP and alternative ventilation strategies during CPR as well as the evaluation of neuronal injury (HIBI) after CA and CPR. The trial will be carried out using a porcine model because prospective, randomized clinical trials in resuscitation are ethically difficult to conduct. The large animal model offers an adequate alternative due to its high translationality.

• DFG Programme: Research Grants
• Co-Investigator: Privatdozent Dr. Robert Rümmler