efficacy and optimum time of administration of ranitidine [Zantac] HCl on the gastric PH and volume in adult patients undergoing elective surgery

ABSTRACT

We examined the effect of single oral dose of ranitidine HCl [Zantac] 300 mg, administered 12 or 2 hours before elective surgery, on intragastric pH and volume. One hundred and twenty five adult inpatients of either sex, aged 20-40 years, ASA physical status I and II scheduled for elective surgery with general anesthesia, were randomly enrolled into three groups Group A [control group] 41 inpatients, group B [oral Ranitidine administered 12 hrs preoperatively] 43 inpatients and group C [oral Ranitidine administered 2 hrs preoperatively] 42 inpatients. There was no statistically significant difference between the three Groups regarding age, sex, ASA physical status, weight, height, and body mass index [BMI]. There was a statistically significant difference between group A vs group B and group A vs group C regarding pH [p <0.0001]. The difference between group B and group C was not significant regarding pH [p > 0.05]. The gastric secretion volume increased in group A more than in group B and C where there were a highly significant difference [p <0.0001] while the difference between group B and C was not significant [p > 0.05]. The proportion of the patients considered [at risk] of significant lung injury should aspiration occur as there was a significant there was a statistically difference between group A vs B [P<0.001], group A vs C [P < 0.05] and no significant difference between group B vs C [p> 0.05]. In conclusion: Oral Ranitidine HCl [Zantac] 300 mg administered twelve or two hours before elective surgery improves condition of gastric secretion at the time of induction of anesthesia, thus reducing the potential risk of pneumonitis, if the aspiration of gastric contents occur following the induction of anesthesia. Our results suggested that the twelve hours dose of ranitidine HCl [Zantac] decreased gastric acidity, secretion volume and numbers of patients at risk of aspiration better than two hours dose but without statistically significant difference