Usefulness of pre-operative oral administration of two consecutive doses, a night before and then in the morning, of omeprazole with domperidone, omeprazole alone, and control (placebo) in reducing the risk of aspiration of gastric contents

Objectives: Pulmonary aspiration of gastric contents remains a recognized perioperative complication that can result in significant morbidity during general anesthesia. Pharmacological strategies aimed at increasing gastric pH and reducing residual gastric volume are commonly employed to decrease aspiration risk. This study evaluated the effectiveness of two pre-operative doses of omeprazole alone or in combination with domperidone on gastric pH, gastric volume, and duodenogastric reflux in patients undergoing elective surgery. Materials and Methods: In this prospective, randomized, placebo-controlled clinical trial, 180 adult patients (American Society of Anesthesiologists physical status I–II), aged 15–70 years and scheduled for elective surgery under general anesthesia, were enrolled. Participants were allocated equally into three groups ( n = 60 each). Group OD received omeprazole 40 mg plus domperidone 10 mg, Group O received omeprazole 40 mg alone, and Group C received placebo. Study medications were administered orally at 9:00 p.m. on the evening before surgery and again at 6:00 a.m. on the day of surgery. Following induction of anesthesia and endotracheal intubation, gastric contents were aspirated through an orogastric tube. Gastric fluid volume and pH were measured, and the presence of bile was assessed using Hay’s sulfur test. Results: Baseline demographic characteristics and perioperative timing variables were similar among the three groups. Patients receiving omeprazole plus domperidone demonstrated the most favorable gastric profile, with a mean gastric pH of 4.12 ± 0.50, gastric volume of 15.31 ± 4.03 mL, and positive bile reflux in 2 patients (3.77%). In comparison, patients receiving omeprazole alone had a gastric pH of 4.01 ± 0.67, gastric volume of 16.30 ± 4.78 mL, and positive bile reflux in 17 patients (28.33%). The placebo group showed a significantly lower gastric pH (2.02 ± 0.50), higher gastric volume (20.85 ± 10.50 mL), and positive bile reflux in 21 patients (35.00%). The combination regimen significantly reduced the proportion of patients meeting aspiration-risk criteria and decreased the occurrence of duodenogastric reflux compared with both omeprazole alone and placebo ( p < 0.0001). Conclusion: Administration of two consecutive pre-operative doses of omeprazole 40 mg combined with domperidone 10 mg was more effective than omeprazole alone or placebo in increasing gastric pH, reducing residual gastric volume, limiting duodenogastric reflux, and decreasing the number of patients classified as being at risk for aspiration. These findings support the use of combined acid-suppressive and prokinetic therapy as part of pre-operative aspiration prophylaxis in elective surgical patients.