title: Use of i.m. ranitidine for the prophylaxis of aspiration pneumonitis in obstetrics.
abstract: Twenty patients who underwent elective Caesarean section received ranitidine 150 mg by mouth 8-14 h, and 50 mg i.m. 90 min, before surgery. Intraoperative gastric aspiration resulted in contents with a pH greater than 2.5 and volume less than 25 ml in all patients (mean pH 6.5 (SD 0.8); mean volume 9.0 (SD 7.2) ml). Sixty patients in labour, who received ranitidine 50 mg i.m. 6-hourly, underwent emergency surgery. Half of this group received, in addition, a single preinduction dose of either 15 or 30 ml of sodium citrate 0.3 mol litre-1. A further 30 patients who remained unmedicated during labour and required emergency surgery received a preinduction dose of 15 or 30 ml of sodium citrate 0.3 mol litre-1 alone. Ranitidine medication resulted in a mean aspirated gastric volume of 31.4 (26.6) ml and pH of 5.3 (2.1); five of 30 patients had a pH less than 2.5. The addition of sodium citrate 0.3 mol litre-1 resulted in gastric pH greater than 2.5 in all patients and a mean gastric volume of 43.2 (38.3) ml. The group who received only sodium citrate 0.3 mol litre-1 had a mean pH of 5.3 (1.1) and a mean volume 122.7 (98.2) ml.
authors.affiliation: Department of Anaesthetics, Westmead Hospital, Sydney, Australia.
authors.forename: R D
authors.initials: RD
authors.lastname: Colman
authors.forename: M
authors.initials: M
authors.lastname: Frank
authors.forename: B A
authors.initials: BA
authors.lastname: Loughnan
authors.forename: D G
authors.initials: DG
authors.lastname: Cohen
authors.forename: R
authors.initials: R
authors.lastname: Cattermole
mesh_terms: D000328:Adult; D000768:Anesthesia, General; D000773:Anesthesia, Obstetrical; D000863:Antacids / Q000627:therapeutic use; D002585:Cesarean Section; D002951:Citrates / Q000627:therapeutic use; D019343:Citric Acid; D005260:Female; D005745:Gastric Acidity Determination; D006801:Humans; D007273:Injections, Intramuscular; D011015:Pneumonia, Aspiration / Q000517:prevention & control*; D011229:Preanesthetic Medication; D011247:Pregnancy; D011899:Ranitidine / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D000863:Antacids; D002951:Citrates; D019343:Citric Acid; D011899:Ranitidine