The relationship between cerebral regional oxygen saturation during extracorporeal cardiopulmonary resuscitation and the neurological outcome in a retrospective analysis of 16 cases

BACKGROUND In recent years, the measurement of cerebral regional oxygen saturation (rSO2) during resuscitation has attracted attention. The objective of this study was to clarify the relationship between the serial changes in the cerebral rSO2 values during extracorporeal cardiopulmonary resuscitation (ECPR) and the neurological outcome. METHODS We measured the serial changes in the cerebral rSO2 values of patients with out-of-hospital cardiac arrest before and after ECPR in Osaka National Hospital. RESULTS From January 2013 through March 2015, the serial changes in the cerebral rSO2 values were evaluated in 16 patients. Their outcomes, as measured by the Glasgow Outcome Scale (GOS) score at discharge, included good recovery (GR) (n = 4), vegetative state (VS) (n = 2), and death (D) (n = 10). In the poor neurological group (VS and D: n = 12; age, 52.8 ± 4.0 years), the cerebral rSO2 values showed a significant increase during ECPR (5 min before ECPR: 52.0 ± 1.8%; 2 min before ECPR: 56.1 ± 2.3%; 2 min after ECPR: 63.5 ± 2.2%; 5 min after ECPR: 66.4 ± 2.2%; 10 min after ECPR: 67.6 ± 2.3% [P < 0.01]). In contrast, in the good neurological group (GR: n = 4; age, 53.8 ± 6.9 years), the cerebral rSO2 values did not increase to a significant extent during ECPR (5 min before ECPR: 61.9 ± 3.1%; 2 min before ECPR: 57.1 ± 4.0%; 2 min after ECPR: 59.6 ± 3.8%; 5 min after ECPR: 61.0 ± 3.7%; 10 min after ECPR: 62.0 ± 3.8% [P = 0.88]). Our study suggested that the patients whose cerebral rSO2 values showed no significant improvement after ECPR might have had a good neurological prognosis. CONCLUSIONS The serial changes in the cerebral rSO2 values during ECPR may predict a patient's neurological outcome. The further evaluation of the validity of rSO2 monitoring during ECPR may lead to a new resuscitation strategy.