Nutrition optimization in enhanced recovery after brain tumor surgery: scoping review of evidence, gaps, and a proposed perioperative nutrition score

Background: Nutrition protocols are integral to enhanced recovery after surgery (ERAS), as inadequate nutrition is associated with adverse outcomes. Yet, evidence regarding the impact of specific nutritional interventions, particularly in brain tumor surgery (ERABTS), remains limited. We performed the first comparison of nutritional strategies in general ERAS versus ERABTS, to clarify outcomes and develop a structured perioperative nutrition score. Methods: We conducted a scoping review of PubMed, Scopus, and Embase (2020-2024) for ERAS protocols incorporating nutrition. A systematic literature review identified ERAS protocols with a nutrition focus. Data were categorized into general surgery ERAS and ERABTS cohorts. Pre- and postoperative nutritional strategies were analyzed in relation to outcomes. Results: A total of 2,908 patients across 22 ERAS studies and 1,802 patients across 14 ERABTS studies met inclusion criteria. Preoperative carbohydrate loading was implemented in 86% of ERAS and 64% of ERABTS studies; however, no consistent improvement in length of stay (LOS) or complications was demonstrated. Preoperative nutritional screening was performed in fewer than 50% of studies and often lacked a structured criterion. Postoperative interventions were inconsistently reported and poorly defined. Across ERABTS studies, favorable but heterogeneous outcomes included improved ambulation (50%), reduced ICU utilization (40%), and lower pain and nausea (25%). Conclusions: Our work highlights that nutritional elements frequently included in ERAS and ERABTS protocols are inconsistently defined and insufficiently linked to outcomes. To address this gap, we propose a perioperative nutrition score (PONS) to improve risk identification and stratification, as well as support tailored nutritional interventions in brain tumor surgery.