Background/Objectives: Shortened clear-fluid fasting is increasingly supported in pediatric anesthesia, yet its combined effects on child-centered perioperative outcomes, family satisfaction, metabolic response, and gastric ultrasonography findings remain unclear. This study evaluated the associations of two routine preoperative fasting practices with preoperative anxiety, perioperative blood glucose, hemodynamic parameters, family satisfaction, and gastric ultrasonography findings in children undergoing elective surgery. Methods: This prospective, two-arm, observational cohort study included 66 children aged 3–12 years with American Society of Anesthesiologists (ASA) physical status I–II scheduled for elective adenotonsillectomy under general anesthesia, following either standard overnight fasting or 5 mL/kg carbohydrate-containing clear apple juice approximately 2 h before surgery. Preoperative anxiety was assessed using the Modified Yale Preoperative Anxiety Scale; blood glucose, hemodynamic parameters, gastric antral cross-sectional area, estimated gastric residual volume, Perlas classification, family satisfaction, fasting duration, and nausea and vomiting were also evaluated. Results: Preoperative anxiety scores were significantly lower in the clear-fluid group than in the overnight fasting group (39.95 ± 20.02 vs. 51.88 ± 22.05; p = 0.003). No significant differences were observed between groups in blood glucose, gastric antral cross-sectional area, estimated gastric residual volume, or Perlas scores. Family satisfaction was significantly higher in the clear-fluid group (8.76 ± 1.66 vs. 4.12 ± 2.00; p < 0.001), and fasting duration was markedly shorter. No perioperative pulmonary aspiration occurred. Conclusions: Administration of 5 mL/kg of carbohydrate-containing clear fluid approximately 2 h before surgery was associated with lower preoperative anxiety and higher family satisfaction, with no significant between-group difference in gastric residual volume.