The Use of Roxatidine Acetate in Fasting Patients Prior to Induction of Anaesthesia as Prophylaxis against the Acid Aspiration Syndrome

Summary

Aspiration pneumonitis is one of the major causes of anaesthesia related deaths. H₂-receptor antagonists are effective drugs for the prevention of the acid aspiration syndrome (Mendelson’s syndrome). The new long-acting H₂-receptor antagonist roxatidine acetate may be the first H₂-receptor antagonist which could effectively reduce acid secretion following a single bedtime premedication on the evening before an operation. A prospective controlled randomised double-blind study was conducted in 60 elective patients undergoing gynaecological operations requiring tracheal intubation. 30 patients received oral roxatidine acetate 150mg at 10pm, the other 30 patients received placebo. Immediately after intubation, at 15 minutes and at the end of the operation gastric pH and the volume of the aspirate were measured. In the placebo group, 13 patients (43%) had gastric pH values below the critical value of 2.5, while in the roxatidine acetate group gastric pH values were raised above 2.5 in all but 3 patients (10%) [p < 0.05]. In the roxatidine acetate group pH values were significantly higher than in the placebo group ( p < 0.01). The mean gastric volume in the placebo group was 23.3 ± 27.1ml, compared to 14.5 ± 9.4ml for roxatidine acetate. The 5 highest gastric volumes were observed in the placebo group (max 146ml). A single bedtime oral premedication with roxatidine acetate 150mg ensures a gastric pH above 2.5 until 11am the following day.