A double blind study of 44 patients (24 placebo, 20 cimetidine) was undertaken to determine the effect of cimetidine on the pH and volume of gastric fluid during anaesthesia. The pH was significantly higher on cimetidine-treated patients than placebo-treated patients at 0, 15, 30 and 45 minutes following intubation. At induction of anaesthesia, mean pH on cimetidine was 4.5 and on placebo mean pH was 2.0. Approximately 70% of patients on cimetidine and 20% on placebo recorded a pH above 2.5 during anaesthesia. The reason for a pH recording of less than 2.5 in seven patients on cimetidine could not be ascertained.
Mean volume of gastric aspirate was slightly lower in the cimetidine group at 0, 15, 30 and 45 minutes, but the differences were not significant.
BrimblecombeR.W., DuncanW.A.M., DurantG.J., EmmettJ.C., GanellinC.R., ParsonsM.E.Cimetidine — a non-thiourea H2-receptor antagonist. J Int Med Res1975; 3: 86.
2.
FordtranJ.S., GrossmanM.I.Third symposium on histamine H2-receptor antagonist: clinical results with cimetidine. Gastroenterology1978; 74: 337.
3.
LongstrethG.F., MalageladaJ.R., GoV.L.M.Effect of cimetidine on gastric functions during and after digestion of ordinary solid meals in duodenal ulcers. Gastroenterology1975; 68: A-85/942, Abstract.
4.
FreelandG.R., HiggsR.H., CastellD.O.The effect of cimetidine on lower oesophageal sphincter pressure in normal subjects. Clin Res1976; 24: 11, Abstract.
5.
KravitzJ.J., Snape JnrW.J., CohenS.Effect of histamine and histamine antagonists on the human lower oesophageal sphincter function. Gastroenterology1978; 74: 435.
6.
MendelsonC.L.The aspiration of stomach contents into the lungs during obstetric anaesthesia. Am J Obstet Gynaecol1946; 52: 191.
7.
CohenS.E.Aspiration syndromes in pregnancy. Anesthesiology1979; 51: 375.
KeatingP.J., BlackJ.F., WatsonD.W.Effects of glycopyrrolate and cimetidine on gastric volume and acidity in patients awaiting surgery. Br J Anaesth1978; 50: 1247.
16.
CoombsD.W., HooperD., ColtonT.Pre-anesthetic cimetidine alteration of gastric fluid volume and pH. Anesth Analg1979; 58: 183.
17.
MaliniakK., VakilA.H.Pre-anaesthetic cimetidine and gastric pH. Anesth Analg1979; 58: 309.
18.
WeberL., HirshmanC.A.Cimetidine for prophylaxis of aspiration pneumonitis: comparison of intramuscular and oral dosage schedules. Anesth Analg1979; 58: 426.
19.
HeaneyG.A.H., JonesH.D.Aspiration syndromes in pregnancy. Br J Anesth1979; 51: 266.
