Ultrasonographic Assessment of Preoperative Metoclopramide on Gastric Volume in Diabetic Patients: A Prospective Controlled Study

Abstract

Background: Diabetic gastroparesis due to autonomic neuropathy and chronic hyperglycemia impairs gastric motility and may persist despite standard preoperative fasting, increasing perioperative aspiration risk. Point-of-care (POC) gastric ultrasound allows objective, real-time bedside assessment of gastric residual volume (GRV) before anesthetic induction. Objectives: This study evaluated whether a single preoperative dose of intravenous (IV) metoclopramide reduces antral cross-sectional area (CSA) and aspiration risk in fasted diabetic patients undergoing elective surgery under general anesthesia. Methods: This prospective, non-randomized controlled study included 60 patients divided into three groups (n = 20 each): Group I (diabetics receiving IV metoclopramide 10 mg, 30 - 60 minutes before ultrasound), Group II (diabetics without intervention), and Group III (non-diabetic controls). After at least 8 hours of fasting, POC gastric ultrasound was performed in semi-sitting (SS) and right lateral decubitus (RLD) positions. The primary outcome was antral CSA (cm²); secondary outcomes included GRV (mL), antral gastric grade (AGG), weight-adjusted GRV (mL/kg), and post-intervention fasting glucose. Results: Antral CSA was lower in metoclopramide-treated diabetics versus untreated diabetics and approached non-diabetic controls. Gastric residual volume decreased in treated versus untreated diabetics and was comparable to controls. Antral gastric grade 0 occurred in 60% of treated diabetics versus 25% of untreated diabetics and 90% of controls (χ² = 17.3, P < 0.001). Grade 2 appeared only in diabetics (10% treated, 20% untreated). Weight-adjusted GRV was lower in treated versus untreated diabetics. Post-intervention fasting glucose differed across groups (P < 0.001). Conclusions: Preoperative IV metoclopramide (10 mg) significantly reduces antral CSA and GRV in fasted diabetic patients, partially normalizing gastric parameters toward non-diabetic levels and lowering aspiration risk.