Background: The rationale for strict fluid fasting for pediatric and adult patients has been questioned recently. Point-of-care tools for the evaluation of gastric content have evolved over time, often using gastric ultrasound. Usually, the gastric antral cross-sectional area (CSA) is determined. A liberal fluid fasting regimen, that is, ingestion of liquid fluids until the call for theatre, does not delay gastric emptying compared to midnight fasting, as evaluated with gastric ultrasound. Anesthesia is safe, and no adverse events result from a liberal regimen. Methods: The ethics committee of LMU Munich approved the study (21-0903). Liberal fluid fasting in a geriatric orthopedic surgery department (LFFgertrud) is a sub-study within a project investigating perioperative neurocognitive disorders (Study Registration: DRKS00026801). After obtaining informed consent from 134 geriatric patients 70 years or older, we investigated the gastric antral cross-sectional area (CSA) prior to and postimplementation of liberal fluid management, respectively. Results: After the implementation of liberal fluid fasting, fasting times for solid food and liquids decreased from 8.8 (±5.5) to 1.8 (±1.8) hours (p < 0.0001). In 39 patients where CSA was obtained, a slight increase in fluid was encountered. No critical amount of gastric content was observed, and no adverse events occurred. Conclusions: A liberal fluid fasting concept was safe even for comorbid elderly patients in orthopedic surgery. Applying a gastric ultrasound may be helpful to increase safety. According to the incidence of complications encountered in our study, it seems indispensable.

Background: Postoperative delirium (POD) is a frequent and serious complication in elderly surgical patients. Liberalising preoperative fluid fasting has been shown to reduce its incidence. However, evidence on long-term cognitive and functional outcomes following POD or liberal fluid fasting remains limited. Objectives: This study investigates whether POD and different fluid fasting regimens are associated with changes in cognitive performance and activities of daily living twelve months after surgery. Methods: As a follow-up to the prospective ‘LFFgertrud’ trial, 89 geriatric patients were contacted by phone twelve months after elective trauma or orthopaedic surgery (March 2023–February 2024). Participants completed four validated questionnaires assessing cognition and everyday functioning: the Short Blessed Test (SBT), EQ-5D-5L, Barthel index (BI), and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Results: The hypotheses regarding the effects of POD and fluid fasting on cognitive and functional outcomes were not statistically supported. In contrast, neurodegenerative disease was strongly associated with poorer outcomes in three of the four follow-up measures (SBT: β = 1.27, p = 0.01; EQ-5D-5L: β = 1.43, p < 0.001; BI: β = −1.63, p < 0.001), and polymedication also emerged as a relevant predictor. Although not statistically significant, descriptive trends indicated that patients who developed POD showed lower cognitive performance and reduced quality of life at twelve months. Conclusions: POD and fluid fasting duration were not significantly associated with long-term cognitive or functional outcomes one year after hospitalisation. The findings highlight the importance of considering pre-existing neurocognitive disease and polypharmacy when assessing the risk of adverse long-term outcomes in older patients. Due to the multifactorial nature of recovery in this population, further research involving larger sample sizes is required in order to gain a better understanding of the factors that influence long-term outcomes.