Comparison of Effect of Various Doses of Mannitol Infusion on Brain Relaxation and Cardiac Function in Patients Undergoing Craniotomy for Supratentorial Brain Tumors

Introduction: Most of the brain tumors are supratentorial tumors accounting for 79% of all tumors. The most common of which gliomas, meningiomas and pituitary tumors. They produce significant mass effects in the brain and certain types are accompanied by significant peritumoral edema that leads to increased intracranial pressure. Mannitol is widely used to reduce intracranial pressure (ICP) in patients with cerebral edema. The use of mannitol for the type of surgery that patients in our study will undergo has been found overall to be beneficial; however, the appropriate dose of mannitol is controversial, particularly since large multiple doses can have negative effects. In the present study, we prospectively assessed the effect of different doses of mannitol on intraoperative brain relaxation and adverse effects in patients undergoing craniotomy for the removal of supratentorial brain tumors. We also sought to determine the mannitol dose to provide adequate brain relaxation with the fewest adverse effects. Objectives: To assess brain relaxation in using different doses of mannitol during craniotomy. Materials and Method: The present study will be conducted in the Department of Anesthesiology, Shyam Shah Medical College and associated Sanjay Gandhi and Gandhi Memorial Hospitals, Rewa, Madhya Pradesh from SEP 2022 to SEP 2023 on 90 patients posted for Craniotomy. patients will be divided into three groups as group-A group-B and group-C. Depending on the dose of mannitol given. Each group was aimed as follows. GROUP A: 20% mannitol 0.5gm/kg GROUP B: 20% mannitol 1.0 gm/kg GROUP C: 20% mannitol 1.5gm/kg A detailed history of all selected patients will be taken. A thorough pre-anaesthetic evaluation including the airway, assessment will be performed. The patients will be explained about the entire procedure, informed consent. Intravenous line will be secured. Monitors will be attached and baseline parameters viz heart rate, systolic and diastolic blood pressure, mean arterial pressure, SpO2, ECG tracings will be recorded. Brain relaxation at the opening of the duramater assessed by a neurosurgeon on scale (ROZET QUENTIN SCALE) from 1 to 4. Result: We found a positive correlation between increased brain relaxation and mannitol dose. The incidence of satisfactory brain relaxation was significantly greater at higher doses of mannitol (1.0 and 1.5 g/kg) compared with the lowest dose (0.5g/kg). Our results showed that although a 0.5- g/ kg dose of mannitol caused minimal electrolyte disturbance, the incidence of satisfactory brain relaxation was low at this dose as compared with that using higher doses. Based on our results, the 1.0-g/kg dose of mannitol can be regarded as the optimal dose producing the satisfactory brain relaxation with the minimal adverse effects.in patient undergoing elective supratentorial brain tumor surgery. Conclusion: The study is ongoing, and the conclusion will be discussed at time of presentation.