DFO (20mg/kg/hr) in normal saline IV for 4 hours for 5 consecutive days

normal saline IV for 4 hours for 5 consecutive days

DFO (20mg/kg/hr) in normal saline for 4 hours for 5 consecutive days

DCI will be defined radiographically as any cerebral infarct on the latest CT scan that was seen within 6 weeks after SAH or before discharge or death, that was not present on admission scan or on the CT scan done within 24 to 48 hours after any aneurysmal treatment procedures. All head CT scans will be reviewed for DCI ascertainment by neuroradiologists blinded to the clinical and TCD data using the standardized protocol.

Clinical outcome at discharge will be assessed using modified Rankin Scale (mRS) as a global functional status. The modified Rankin scale evaluates global disability and handicap; scores range from 0 (no symptoms or disability) to 6 (death). Good mRS will be defined as score of ≤ 2.

Spectral analysis of the relationship between arterial pressure and blood flow velocity in the bilateral middle cerebral arteries (measured via TCD). Autoregulation will be assessed from the phase and gain of the transfer function. Phase shift reflects the temporal difference between cerebral flow velocity fluctuations with respect to arterial pressure fluctuations. When the fluctuations of both flow and pressure are almost synchronous, the phase shift approaches zero, reflecting impaired cerebral autoregulation. Transfer function gain reflects the magnitude of transmission of arterial pressure fluctuations to cerebral blood flow velocity fluctuations. Lower gain, particularly in the low frequency (< 0.1 Hz) range, is reflective of more effective cerebral autoregulation. Coherence reflects the degree of linear dependence between pressure and flow fluctuations. Thus, it provides a measure of validity of the metrics (gain and phase) derived from the linear transfer function.