Nitric Oxide Consumption as a Predictor of Vasospasm in Subarachnoid Hemorrhage

Summary

The goal of this observational study is to understand if angiographic cerebral vasospasm (CV) can be predicted by levels of nitric oxide (NO) consumption in patients with aneurysmal subarachnoid hemorrhage (SAH). To reach this goal, the investigators will compare NO consumption levels in SAH and non-SAH patients. NO consumption levels will be analyzed from samples of participants' cerebral spinal fluid (CSF).

Detailed Description

After enrollment, the investigators will collect patients' demographics and most relevant clinical characteristics of the patients. For patients with SAH, the investigators will collect an-1 ml aliquot of CSF from the drainage circuit daily, (using a sterile procedure that involves a valve of the closed system circuit located distally to the patient, before the collection container), for a period of 15 days following SAH. The samples will be stored at -80 degrees. The investigators will perform daily Transcranial Doppler (TCD) monitoring to assess whether the patients have cerebral vasospasm. In case of suspected vasospasm, and in all comatose patients after 4 days from the bleeding, a CT angiography will be performed to define the angiographic CV. For the control group, discarded 1 ml-aliquot of CSF will be collected at the time of needle insertion for spinal anesthesia. At the end of the protocol, the study population will be divided in 3 groups: * patients with SAH and vasospasm * patients with SAH and no vasospasm * control group

Eligibility Criteria