Brain tissue oxygenation guided therapy and outcome in non-traumatic subarachnoid hemorrhage

Brain hypoxia can occur after non-traumatic subarachnoid hemorrhage (SAH), even when levels of intracranial pressure (ICP) remain normal. Brain tissue oxygenation (PbtO₂) can be measured as a part of a neurological multimodal neuromonitoring. Low PbtO₂ has been associated with poor neurologic recovery. There is scarce data on the impact of PbtO₂ guided-therapy on patients' outcome. This single-center cohort study (June 2014-March 2020) included all patients admitted to the ICU after SAH who required multimodal monitoring. Patients with imminent brain death were excluded. Our primary goal was to assess the impact of PbtO₂-guided therapy on neurological outcome. Secondary outcome included the association of brain hypoxia with outcome. Of the 163 patients that underwent ICP monitoring, 62 were monitored with PbtO₂ and 54 (87%) had at least one episode of brain hypoxia. In patients that required treatment based on neuromonitoring strategies, PbtO₂-guided therapy (OR 0.33 [CI 95% 0.12-0.89]) compared to ICP-guided therapy had a protective effect on neurological outcome at 6 months. In this cohort of SAH patients, PbtO₂-guided therapy might be associated with improved long-term neurological outcome, only when compared to ICP-guided therapy.