PRE-ANAESTHETIC ORAL LANSOPRAZOLE FOR THE PROPHYLAXIS OF MENDELSON'S SYNDROME AND IMPACT OF DUODENOGASTRIC REFLUX ON pH AND VOLUME OF GASTRIC CONTENTS

Background. Lansoprazole, a proton pump inhibitor, is used in peptic ulcers and other acid dyspeptic disorders. The aim of this study is to determine whether a single oral dose of lansoprazole 30 mg, administered a night before surgery , is effective on pH and volume of gastric contents after excluding those samples contaminated with duodenogastric refluxate (DGR). Patients and Methods. This clinical trial was conducted in 112 adult patients of both sex, ASA physical status I-II, and aged 15-70 y r. The patients in group C (control) received placebo while group L (lansoprazole 30 mg) orally at 9.00 p.m., a night before elective surgery . On the next day , gastric contents were aspirated with a large bore, multi-orifices gastric tube passed through an endotracheal tube placed blindly in esophagus after tracheal intubation and analyzed for the presence of bile salts, pH and volume. Results. Thirty three samples (30 %) out of 110 were contaminated with duodenal contents. DGR significantly affected the pH and volume in both the groups. Lansoprazole, after excluding those samples contaminated either with duodenal fluid or blood, significantly increased pH (P<0.0001), decreased volume (P=0.0326) and the proportion of the patients (10.52 % versus 30.76%) considered” at risk” compared with Placebo (P=0.0475) according to the criteria defined (pH ≤ 2.5 and volume ≥ 25 ml). Conclusions. Lansoprazole 30 mg given orally at 9.00 p.m., a night before surgery , significantly decreased the number of patients at risk of aspiration pneumonitis at the time of induction of anesthesia if the aspiration of gastric contents occurs.