Cerebral Nitrosative/Oxidative Stress in Aneurysmal Subarachnoid Haemorrhage

Aneurysmal subarachnoid haemorrhage (SAH) carries a high morbidity and mortality, which is in part due to the development of secondary brain injury. The mechanisms behind this remain incompletely understood, but oxidative/nitrosative stress and disturbances in vasoregulatory mechanisms are believed to be involved. The present study aims to characterise the transcerebral exchange of oxidative/nitrosative stress markers and nitric oxide metabolites during the early phase after SAH compared to healthy volunteers, including the influence of induced changes in arteriel oxygen tension.

Inclusion Criteria (patients):Age ≥ 18 yearsAdmission to the NICU at RigshospitaletDiagnosis of aneurysmal SAHNeed for sedation and mechanical ventilation after the aneurysm has been securedInitiation of study possible ≤3 days after the ictusClosest relatives understand written and spoken Danish or EnglishExclusion Criteria (patients):Brain death before inclusionExpected death within 24 hoursFailed or conservative treatment of the aneurysmSevere acute lung failure with a PaO2/FiO2-ratio ≤16 kPaSevere chronic lung failure with habitual long-term oxygen therapyHabitual treatment with medication directly affecting NO metabolism (e.g., sildenafil)Inclusion Criteria (patients):Age 40-60 years50/50 sex distribution (6 men and 6 women)Healthy (including no prior cerebrovascular disease)No regular medication or recreational drug useUnderstands written and spoken Danish or English