The aim of this study is to determine the effects of the level of metabolites used in routine on mortality and morbidity in patients who will undergo intracranial surgery with craniotomy.

In this study, in patients who are planned to have an intracranial mass operation with craniotomy, their medical histories, demographic features, comorbidities, preoperative radiotherapy treatment, the parameters examined in the preoperative routine will be collected as a file scan (previous operations, GKS, laboratory values). The classification of patients according to the 2016 World Health Organization Central Classification of Nervous System Tumors (WHO-CNS classification) and whether it is glial or non glial will be recorded from the clinical file. Intraoperative; hemodynamic data of patients; heart rate, diastolic, systolic and mean arterial pressures, fluid and blood products delivered, anesthetic and other medications, and blood gas samples will be written from the anesthesia document after the operation is finished. For the study, the application of the anesthesiologist for the patient will not be interfered. If postoperative patients are sent to the intensive care unit, their laboratory values and clinical observations (mortality, morbidity, neurological sequelae, imaging techniques, GOSE (Glasgow outcome skale)) will be recorded. In our study, mortality and morbidity will be evaluated 30 days postoperatively, and if the patient was sent to the service from the intensive care unit in this process, the values in the postoperative clinic (mortality, morbidity, neurological evaluation, imaging techniques, pathology results) will be recorded from the patient document. If the patient was discharged 30 days before, outpatient data will be recorded. The patients will be classified by evaluating the collected data (intraoperative hemodynamic data, blood transfusions, postoperative neurological sequel, postoperative complications and mortality).

In our study; the effects of lactate level on mortality and morbidity will be investigated in patients undergoing an intracranial mass operation with general anesthesia.

Inclusion Criteria:

1. Having an intracranial mass operation with craniotomy
2. No history of congestive heart failure
3. No kidney and liver dysfunction
4. Not pregnant
5. Not taking inotropic drugs during the operation
6. Receiving less than four red blood product replacements during the operation

Exclusion Criteria:

1. Patients with a history of congestive heart failure
2. Patients with kidney and liver dysfunction
3. Patients who need an inotropic agent to adjust blood pressure during the operation
4. Patients who have undergone four or more red blood product transfusions during the operation
5. Pregnant patients

It is planned to include intracranial mass operations performed by craniotomy between 10 December 2019 - 10 December 2020 in Trakya University Faculty of Medicine, Department of Neurosurgery.