Impact of Different Fasting Strategies on Gastric Ultrasound and Anxiety Levels in Children

Enhanced Recovery After Surgery (ERAS) protocols are evidence-based perioperative strategies designed to attenuate the surgical stress response, maintain metabolic stability, and accelerate postoperative recovery¹. Within ERAS pathways, shortening preoperative fasting duration and allowing the intake of oral carbohydrate-containing clear fluids play an important role.

In pediatric patients undergoing elective surgery under general anesthesia, prolonged preoperative fasting has been associated with dehydration, hypoglycemia, increased catabolism, and significant preoperative anxiety²-³, all of which may negatively influence perioperative outcomes. Consequently, pediatric preoperative fasting practices have been reassessed in recent years by several scientific societies⁴.

According to the most recent guideline published by the American Society of Anesthesiologists (ASA) in 2023, the recommended fasting period for clear fluids in children is 2 hours before anesthesia⁵. However, European guidelines suggest that the intake of clear fluids can be safely continued up to 1 hour before anesthesia in healthy pediatric patients⁴. Despite these updated recommendations, traditional fasting practices remain common in clinical settings, often resulting in unnecessarily prolonged fasting times in children.

Various approaches ranging from traditional overnight fasting to more liberal strategies-such as preoperative oral carbohydrate loading and the Sip-Til-Send protocol (allowing clear fluid intake until the patient is called to the operating room)⁴-⁶-have been proposed. Large prospective studies have demonstrated that shortened and liberal clear-fluid fasting protocols do not increase the risk of pulmonary aspiration in elective pediatric surgery⁶. Nevertheless, randomized and objective data comparing the effects of these protocols on gastric volume and perioperative comfort parameters-such as anxiety, nausea, vomiting, and pain-remain limited.

Gastric ultrasonography is a non-invasive, repeatable, and reliable bedside method for assessing gastric content and volume, providing an objective evaluation related to aspiration risk⁷.

In addition, validated assessment tools such as the Modified Yale Preoperative Anxiety Scale (m-YPAS) enable quantitative evaluation of perioperative psychological stress in children⁸-⁹.

Evaluating these objective and patient-centered outcomes within a randomized controlled design may contribute to determining optimal fasting strategies in pediatric anesthesia.

Therefore, the primary aim of this study is to compare the effects of different preoperative fasting protocols (standard fasting, preoperative carbohydrate loading, and the Sip-Til-Send approach) on preoperative anxiety levels in pediatric patients undergoing elective surgery, using the Modified Yale Preoperative Anxiety Scale (m-YPAS).

As secondary outcomes, the investigators aimed to evaluate the effects of these fasting strategies on gastric ultrasound findings (antral cross-sectional area [CSA], gastric volume, and fluid grading) as well as perioperative comfort and safety parameters, including nausea-vomiting, pain, emergence delirium, hemodynamic variables, and blood glucose levels.

Inclusion criteria

• Patients scheduled to undergo elective surgery under general anesthesia for circumcision, undescended testis, inguinal hernia, and/or hypospadias (inguinoscrotal surgery)
• Patients with an ASA physical status classification of I-II
• Patients able to tolerate oral intake in the preoperative period and comply with the assigned fasting protocol
• Written informed consent obtained from parents or legal guardians

Exclusion criteria

• Patients with ASA physical status III or higher
• Patients requiring emergency surgery
• History of gastroesophageal reflux disease, gastrointestinal motility disorders, or metabolic/neurological diseases affecting gastric emptying
• History of upper gastrointestinal surgery
• Active upper respiratory tract infection or lower respiratory tract infection within the previous 2-4 weeks
• Severe pulmonary disease, including uncontrolled or moderate-to-severe persistent asthma, bronchopulmonary dysplasia, cystic fibrosis, interstitial lung disease, or other chronic lung diseases
• Diabetes mellitus or endocrine/metabolic disorders that may affect perioperative glucose metabolism
• Obese patients with high aspiration risk (>95th percentile for age)
• Cognitive or communication impairments that may interfere with compliance with the study protocol
• Grade 2 or Grade 3 gastric fullness detected on preoperative gastric ultrasonography
• Lack of written informed consent from parents or legal guardians for participation in the study