Magnesium and Intraoperative Blood Loss in Meningioma Surgery

The Effect of Magnesium Sulphate on Intraoperative Blood Loss in Meningioma Patient Undergoing Craniotomy With Tumor Removal

Meningioma is the most common central nervous system tumor and craniotomy with tumor removal was associated with moderate blood loss and blood transfusion. Magnesium has hypotensive effect and probably reduce intraoperative blood loss. Whether or not magnesium sulphate can reduce intraoperative blood loss and improve postoperative cognitive function is still inconclusive. So the investigators conduct the randomized control trial to compare the effect of magnesium with placebo control in blood loss and cognitive function in meningioma patient undergoing craniotomy.

The investigators enroll 120 patient who admitted for craniotomy for meningioma removal. Then, the patients will be divided into two groups. The first group or group Mg will receive magnesium sulphate 40 mg/kg infuse for 30 min (started at skin incision), and then infuse magnesium sulphate 10 mg/kg/hr until the dura will be closed. The another group or normal saline group will receive the same amount of 0.9% sodium chloride. The anesthesia and surgery are standardized. The recorded data include patient demographic data, intraoperative blood loss, hemodynamics and pre and postoperative Montreal cognitive assessment score.

Inclusion Criteria:

• Meningioma patient
• Schedule for supratentorial craniotomy with tumor removal
• American society of anesthesiologists physical status 1-3
• Age 18-70 years
• No alteration of conscious (full Glasgow coma score) and well cooperate
• Expected to extubation after operation

Exclusion Criteria:

• Unstable hemodynamic (severe hypotension or hypertension who receive antihypertensive and vasopressor before surgery but not include baseline oral antihypertensive drug)
• Known cardiac disease from either history, physical examination or investigation
• Patient who have heart block
• Hepatic disease (Child Pugh Score Class C)
• Renal insufficiency (eGFR < 60 ml/min from Chronic Kidney Disease Epidemiology Collaboration equation)
• Allergy to magnesium or other drugs use in the study
• Patient who receive calcium channel blocker drug
• Pregnancy
• Patient who receive magnesium for treatment such as arrhythmia or preeclampsia
• Hypermagnesemia (more than 2.6 mg/dL) before surgery
• BMI more than 30 kg/m2
• Patient who probably have brain herniation from increase intracranial pressure