Abstract 14166: Multimodality Monitoring for Cerebral Perfusion Pressure Optimization in Comatose Patients after Cardiac Arrest
Background and Purpose: Limited data exists to recommend specific cerebral perfusion pressure (CPP) targets in patients after cardiac arrest (CA). We sought to determine the feasibility of brain multimodality monitoring (MMM) for optimizing CPP and potentially reducing secondary brain injury after CA.
Methods: We performed retrospective analysis on MMM in 15 comatose patients after CA (median monitoring: 80 hours). Physiological measures were averaged over one-hour intervals corresponding to each microdialysis sample. Metabolic crisis (MC) was defined as a lactate/pyruvate ratio (LPR) > 40. Brain tissue hypoxia (BTH) was defined as PbtO2 <15 mm Hg. Pressure reactivity index (PRx), oxygen reactivity index (ORx) and flow reactivity index (FRx) were calculated.
Results: Median age was 56 years, median GCS score 3, and median ROSC time was 25 minutes. Univariate analyses showed that the risk of BTH and MC increased with lower CPP values. Multivariable analyses showed that CPP <70 mm Hg was associated with a greater risk of BTH (OR 1.7, 95% CI 1.3-2.3, P < 0.01) compared to CPP 80-90 mm Hg as a reference range. However, CPP level was not associated with MC after adjusting ETCO2 and systemic glucose. Eight patients died (53%). Non-survivors had higher PRx values indicating loss of pressure autoregulation.
Conclusions: PbtO2 monitoring can be used to identify CPP targets for optimal brain tissue oxygenation. In patients who do not undergo MMM, maintaining CPP >70 mm Hg may reduce the risk of BTH.
- © 2012 by American Heart Association, Inc.