Regional cerebral saturation monitoring during withdrawal of life support until death

Abstract

AimsThe aim of this pilot study was to explore the regional cerebral oxygen saturation (rSO2) during the process of dying in Intensive Care Unit (ICU) patients in whom it was decided to withdraw life support. MethodsRegional cerebral saturation was measured from the moment active treatment was stopped until the moment of death, defined as the onset of asystole. Simultaneously, heart rate and arterial blood pressure were recorded using a radial arterial catheter. Baseline rSO2 values were calculated as mean values over one hour in stable haemodynamic conditions immediately after the decision to withdraw life support. ResultsCerebral saturation was measured in six dying ICU patients. The mean age of patients was 64year. The median baseline rSO2 value was 64% (58%–68%). At time of death, median rSO2 was 33% (7%–40%). The median decrease in rSO2 from baseline until death was 31% (25%–45%). The median decrease in rSO2 observed during the last hour before time of death was 20% (12%–31%). ConclusionA continuous and patient specific decrease in rSO2 was observed in all patients with a simultaneous decrease in MAP. However, the absolute rSO2 value at moment death was clinically determined, had a broad range, indicating that there is no clear cut-off rSO2 value for death probably due to the heterogeneity of the studied population. Taken together, these observations highlight the importance of following trends and comparing rSO2 values in the cardiac arrest setting.