Effects of Two Different Goals of Fluid Management in Patients Undergoing Supratentorial Tumour Resection

Neurosurgical operations are characterised by major fluid shift, frequent use of diuretics, and prolonged operative time. The role of fluid therapy in these patients is very critical; hypovolemia might decrease cerebral perfusion; while, fluid over-infusion might swell the brain (1-3). Thus, fluid management in these procedures complex and challenging. Evidence on the optimum protocol for intraoperative fluid management in neurosurgical patients is still lacking. Adequate intracranial volume management is considered a key factor that would overcome the tumour bulk and the surrounding vasogenic oedema facilitating surgical access . Thus, a relaxed brain is one of the targets of intraoperative fluid management during craniotomy. The slack brain would allow proper surgical retraction and consequently, reduces brain retractor ischemia. Brain relaxation scale (BRS) had shown a good correlation with intracranial pressure thus, an increasing interest was paid to BRS as a simple surrogate for intracranial pressure (4-8). Goal-directed hemodynamic therapy (GDT) in the operating room is a term used to describe the use of defined hemodynamic targets to guide intravenous fluid and inotropic therapy. Pulse pressure variation (PPV) is one of the robust dynamic indices of fluid responsiveness which is based on heart-lung interactions (9-12). GDT had been frequently investigated in the operating room in high-risk patients especially in major surgery. However, the impact of GDT on patient outcomes, especially BRS, is not well evaluated in brain surgery (12-15). In this study, we evaluated PPV-guided fluid management compared to standard fluid management in patients undergoing supratentorial mass excision. We hypothesised that in these procedures, GDT might restrict intraoperative fluid volume, improve brain relaxation, and provide stable patient hemodynamics.