Effects of famotidine on gastric pH and residual volume in pediatric surgery

Abstract

Aspiration pneumonitis is a severe complication of anesthesia. The objectives of this study were to determine if preoperative famotidine, a new histamine2-receptor antagonist, given by mouth either the evening before or the morning of elective surgery, reduced gastric residual volume and increased gastric pH in pediatric patients. Either famotidine or placebo (or both) were orally administered to 58 children (aged 2-17 years). The patients were randomly assigned to four groups: Famotidine-Famotidine, Placebo-Placebo, Placebo-Famotidine, and Famotidine-Placebo; subjects in the Famotidine-Famotidine group received two doses of famotidine (0.5 mg.kg-1 per dose), those in the Placebo-Placebo group, two doses of placebo, those in the Placebo-Famotidine and Famotidine-Placebo group, one dose of each by mouth. The Famotidine-Famotidine group received one dose of famotidine at 22:00 the evening before surgery and a second dose 60-90 min before the scheduled time of surgery. The Placebo-Placebo group received two doses of placebo at the same times as the Famotidine-Famotidine group. The Placebo-Famotidine group received a dose of placebo the night before surgery and a dose of famotidine the morning of surgery; the Famotidine-Placebo group received famotidine the night before surgery and placebo the morning of surgery. The administration of famotidine on the morning of surgery significantly increased gastric pH (4.8 vs. 1.3) in comparison with placebo, as did two doses of famotidine (6.6). Famotidine failed to reduce gastric residual volume significantly in any group. The administration of famotidine significantly reduced the number of pediatric patients considered at higher risk for aspiration pneumonitis, despite not decreasing gastric residual volume.

Assessment of Age-Related Changes in Pediatric Gastrointestinal Solubility

“…Average (mean) values pertaining to neonates (0-28 days) and infants (1-12 m) are illustrated for reference (red -x's). (b) Fasting gastric pH amongst pediatrics (black circles) is depicted as the central tendency, either mean or median, from separate investigations (26)(27)(28)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55). Studies where gastric pH values was quantified over specific age range without denoting the group's mean age were graphically depicted using the middle of the age range.…”

Reversible and pH-dependent weak drug-excipient binding does not affect oral bioavailability of high dose drugs

“…A passively‐absorbed weakly basic amine drug would be positively charged in the acidic pH in the stomach. However, certain treatments, such as antacids, can increase gastric pH [21,22] . Therefore, drug‐excipient interaction was studied at pH 4.5, since it was close to the pH of the upper small intestine and the antacid‐treated gastric pH [23] .…”

Upper Gastrointestinal Tract Bleeding in Critically Ill Pediatric Patients

“…By inhibiting gastric acid secretion, H 2 -receptor antagonists also decrease gastric fluid production and potentially decrease the risk for aspiration during anesthesia. [136][137][138][139][140] In this situation, they showed benefit when administered in combination with a prokinetic agent, 137 but results of studies evaluating monotherapy with the agents had inconsistent results. 136,[138][139][140] Neonates with increased gastric residuals after enteral feeding had decreased gastric residuals and gastric emptying time with the addition of cimetidine.…”