Vitamin D supplementation not only has beneficial effects on morbidity and mortality in critically ill patients but it may also lead to alleviate of seizure, brain edema, infection, pain and some other perioperative complications, possibly in part through an attenuation of the immune response.In this trial patients with brain tumor under craniotomy will receive a single high dose vitamin D compared to control group.

A randomized, double blind, controlled trial will be conducted in neurosurgery ward, operating room (OR) and intensive care unit (ICU) in Tehran, Iran. After a full review of the inclusion and exclusion criteria and explanation of the risks and benefits of the study, written consent form will be completed. The participants are 60 eligible hospitalized patients that diagnosed with brain tumor and need to craniotomy, aged ≥ 18 years. Intervention patients will be received an intramuscular (IM) single dose of vitamin D (300000 IU). Patients will be evaluated for occurrence of perioperative complications and clinical outcomes immediately after surgery until 1 month later and 1 and 6 months mortality.

Inclusion Criteria:

• Written informed consent of patient or legal representative
• 25(OH)D level below 20ng/dL

Exclusion Criteria:

• Other trial participation, including previous participation in the pilot trial
• Pregnant or lactating women
• Hypercalcemia
• Hyperphosphatemia
• Tuberculosis
• Sarcoidosis
• History of nephrolithiasis
• History of hyperparathyroidis
• Medications that interfere with vitamin D metabolism
• Renal Insufficiency