Biological Markers in Patients Presenting Aneurism Coiling for Subarachnoid Hemorrhage

The investigators plan to screen all patients who were consecutively admitted from January 1, 2003 to our neurosurgical intensive care unit after a clinical diagnosis of SAH confirmed by cerebral angiography and treated with a coiling procedure. Patients for whom a decision was made by the treating physician to either forego any invasive treatment or to perform open surgical clipping were excluded. Clinical, biological and radiological characteristics will be recorded during the course of hospitalization. This observational study will be performed according to standard procedure.

Admission characteristics. At admission, the investigators plan to anonymously record age, sex, GCS, presence of motor deficit, presence of clinical seizure and WFNS score. The GCS refers to the value at admission before any treatment with sedative drugs. The cohort was divided into two groups, an admission coma group for patients with GCS<13 (WFNS 4 or 5), and a non-coma group for patients with GCS313 (WFNS 1 to 3).

Admission biological sampling of venous blood are routinely performed to measure S100beta and troponin per standard clinical practice in our ICU. Troponin I and S100beta levels will be considered high for values higher than 0.5 mg/L (corresponding to 5 times the maximum normal range) to be consistent with previous studies and to ensure high specificity.

Admission radiological characteristics are obtained from the admission CT-scan and the initial angiogram. The CT-scan will be reviewed by a neuro-radiologist and classified according to the modified Fisher score. Hydrocephalus and intraventricular hemorrhage at admission were also registered. Aneurysm site and number of aneurysms were obtained from the initial angiogram.

ICU Management. The ICU management will not be modified for this study. Briefly, a central venous line and an arterial catheter are routinely inserted at admission before coiling. An external ventricular drain (EVD) is inserted in patients with CT evidence of hydrocephalus, WFNS grade between III to V, or a transcranial Doppler pulsatility index greater than 1.2, suggestive of increased intracranial pressure. The EVD is routinely connected to an external pressure strain gauge to monitor ICP according to a recently published protocol.