Continuous monitoring of intracranial pressure and end tidal carbon dioxide variations in traumatic brain injury: introducing the carbon dioxide reactivity index (CO2Rx).
Paolo Gritti, Marco Bonfanti, Rosalia Zangari, Ezio Bonanomi, Maria Di Matteo, Davide Corbella, Alessia Farina, Lorenzo Lecchi, Tommaso Togni, Pietro Mandelli, Luigi Andrea Lanterna, Francesco Biroli, Ferdinando Luca Lorini
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引用次数: 0
Abstract
Purpose: The continuous monitoring of cerebral metabolic autoregulation in patients with severe traumatic brain injury (TBI) is poorly documented in the literature and largely absent from clinical practice. This study aimed to assess whether variations in intracranial pressure (ICP) and end-tidal carbon dioxide (ETCO2) can form the basis of an index for cerebrovascular autoregulation reactivity, and whether this index can improve the prediction of clinical outcomes in both adult and pediatric TBI patients.
Methods: Data from adult and pediatric patients with severe TBI were retrospectively analyzed. The Carbon Dioxide Reactivity Index (CO2Rx) was introduced as a novel tool to assess cerebrovascular reactivity in response to variations in CO2 and ICP. CO2Rx was calculated by analyzing the relationship between ICP and ETCO2, sampled at approximately 5-minute intervals, using linear correlation within moving time windows ranging from 40 to 180 min in 10-minute increments. The discriminatory power of CO2Rx in predicting clinical outcomes was evaluated through Receiver Operating Characteristic (ROC) curve analysis. The primary outcome measures included in-hospital mortality and the 12-month Glasgow Outcome Scale-Extended (GOSE) score.
Results: The study included 218 TBI patients (40 pediatric and 178 adult). CO2Rx values showed a significant correlation with outcomes, with a CO2Rx threshold of 0.28 effectively distinguishing between favorable and unfavorable outcomes. For the fatal/non-fatal outcome, the CO2Rx crude model alone had an Area Under the Curve (AUC) of 0.737. When combined with other predictors (Impact Core + ICP + CO2Rx), this model achieved the highest AUC of 0.929.
Conclusion: CO2Rx demonstrated significant predictive value for mortality and unfavorable outcomes in TBI patients, serving as a continuous index of cerebrovascular reactivity to CO2. It holds potential to improve severe TBI management by optimizing the interaction between ventilation and metabolic autoregulation.
期刊介绍：
The Journal of Clinical Monitoring and Computing is a clinical journal publishing papers related to technology in the fields of anaesthesia, intensive care medicine, emergency medicine, and peri-operative medicine.
The journal has links with numerous specialist societies, including editorial board representatives from the European Society for Computing and Technology in Anaesthesia and Intensive Care (ESCTAIC), the Society for Technology in Anesthesia (STA), the Society for Complex Acute Illness (SCAI) and the NAVAt (NAVigating towards your Anaestheisa Targets) group.
The journal publishes original papers, narrative and systematic reviews, technological notes, letters to the editor, editorial or commentary papers, and policy statements or guidelines from national or international societies. The journal encourages debate on published papers and technology, including letters commenting on previous publications or technological concerns. The journal occasionally publishes special issues with technological or clinical themes, or reports and abstracts from scientificmeetings. Special issues proposals should be sent to the Editor-in-Chief. Specific details of types of papers, and the clinical and technological content of papers considered within scope can be found in instructions for authors.
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