Amplitude-Integrated Electroencephalography and Brain Oxygenation for Postcardiac Arrest Patients with Targeted Temperature Management

Abstract

Brain injury is the most common cause of death postcardiac arrest. Amplitude-integrated electroencephalography (aEEG) is suggested to be useful in the prognostication in cases of postcardiac arrest brain injury. However, combined monitoring with aEEG and regional oxygen saturation (rSO2) for postcardiac arrest syndrome (PCAS) patients to improve accuracy has not been reported. The purpose of this prospective observational study is to assess the usefulness of aEEG and rSO2 for PCAS patients with targeted temperature management (TTM) to predict neurological outcome and possibly identify the pathophysiology of postcardiac arrest brain injury. PCAS patients with TTM at 34°C were monitored by aEEG and rSO2 immediately after admission to the intensive care unit and evaluated at the start of monitoring, and 24 and 48 hours after return of spontaneous circulation (ROSC). Patients were divided into two groups according to electroencephalography (EEG) pattern: a continuous EEG (C) pattern group and a noncontinuous EEG (NC) pattern group. Patients with C pattern had a significantly more favorable neurologic outcome compared with patients with an NC pattern at each point in time. No significant difference in rSO2 values was observed between the C pattern and the NC pattern at any time point. Variation coefficient at rSO2 in the NC group was significantly greater than that in the C group from the start of the monitoring to 24 hours. aEEG is useful in predicting outcome for PCAS patients whereas rSO2 is not.

Parameters Influencing Brain Oxygen Measurement by Regional Oxygen Saturation in Postcardiac Arrest Patients with Targeted Temperature Management

“…The web program that we used to statistically analyze CV is www1.fpl.fs.fed.us/covtestk.html. This method was mentioned in a previous study (Ihara et al, 2019). A p-value <0.05 was also considered statistically significant.…”

“…The details of the TTM protocol have been described in our previous study (Ihara et al, 2019). In brief, patients who remained comatose after return of spontaneous circulation (ROSC) were treated with TTM at 34°C for 24 hours.…”

“…In contrast, Ibrahim et al (2015) reported that there was no difference between the rSO 2 of survivors and nonsurvivors in the ICU setting. Recently, Ihara et al (2019) showed that there was no difference in the rSO 2 value between severely brain-injured PCAS patients with abnormal amplitude-integrated electroencephalography (aEEG) and mildly brain-injured patients with continuous aEEG wave. This was because the rSO 2 of patients with abnormal aEEG had a dramatically wider range than that of patients with normal aEEG.…”

“…This was because the rSO 2 of patients with abnormal aEEG had a dramatically wider range than that of patients with normal aEEG. It was concluded that this variation in rSO 2 in patients with severe brain injury may indicate the pathophysiology of postcardiac arrest brain injury owing to impaired cerebrovascular autoregulation (CVAR) and cerebral blood flow (CBF) (Ihara et al, 2019).…”

“…Therefore, by investigating the relationship between rSO 2 and these parameters, we could indirectly estimate brain oxygenation in the injured brain. This study is a post hoc analysis of our previous investigation (Ihara et al, 2019) estimating the relationship between rSO 2 and parameters such as SaO 2 , Hb, PaCO 2 , MAP, and BT.…”