The Optimal Dose of Mannitol for Intraoperative Brain Relaxation During the Operation of Aneurysmal Subarachnoid Hemorrhage
The Optimal Dose of Mannitol for Intraoperative Brain Relaxation During the Operation of Aneurysmal Subarachnoid Hemorrhage
Aneurysmal subarachnoid hemorrhage (aSAH) tended to lead to a sudden increase in
 intracerebral pressure (ICP), which can cause decreased cerebral perfusion and transient
 global cerebral ischemia. Early clipping and coiling of aneurysms and surgical evacuation of
 intracerebral hematoma were recommended for aSAH patients. However, the high ICP made it
 difficult to separate the subarachnoid space during the operation. Effective reduction of ICP
 was the key to the succession of the operation. But there is a lack of consensus on the
 management of raised ICP in aSAH. Mannitol is widely used to reduce ICP in patients with
 cerebral edema. The potential mechanism including decreasing the viscosity of the blood
 improving regional cerebral microvascular flow and oxygenation and increasing intravascular
 volume due to increased plasma osmolality. The magnitude of the pressure reduction was
 correlated with the intact intracranial automatic adjustment function. However, the
 hypochloremic metabolic alkalosis, hypernatremia, hypokalemia and renal failure associated
 with mannitol overdose must be considered and the effective dose and the duration of its
 administration were still unknown. The aims of this study were to determine the most
 appropriate mannitol dose to provide adequate brain relaxation in aSAH patients with the
 fewest adverse effects.
Inclusion Criteria:

 -  Patients with acute subarachnoid hemorrhage

 -  Patients who underwent frontal-temporal craniotomy pterional approach aneurysm
 clipping surgery under general anesthesia.

 -  Patients operated by the same surgeon.

 Exclusion Criteria:

 -  Patients who does not agree to the surgery.

 -  Patients who have congestive heart failure and kidney insufficiency.

 -  Patients who have electrolyte imbalance.