Korean J Anesthesiol.  1986 Oct;19(5):439-447.

Changes of Gastric pH , Free Acidity and Total Acidity in Anticholinergics and Cimitidine Pretreated Groups of Pre-and Post-anesthesia in Surgical Patients

• Oh YS
• Lee CH

Abstract

Aspiration and resultant chemical pneumonitis remain a serious hazard associated with the administration of anesthesia. Anticholinergic drugs are commonly used to reduce the volume and acidity of gastric secretion. We studied the effectiveness of atropine, glycopyrrolate and cimetidine in increasing gastric pH, free acidity and total acidity in the pre-and the 1hr post-anesthesia. Fifty patients scheduled for elective surgery in Dept. of Ansthesiology in EWUH, were randomly allocated into five groups with ten patients in each group. Patients in the control group were given neither anticholinergics nor cimetidine; patients in group I received 0.5 mg of atropine intramuscularly 1 hr. before induction of anesthesia, patients in group II received 0.2 mg of glycopyrrolate intramuscularly 1 hr. before induction of anesthesia, patients in group III received 200 mg of cimetidine intravenously and atropine as in group I, patients in group IV received 200 mg of cimentidine intravenously and glycopyrrolate as in group II. The results were as follows; 1) There were not any significant changes in the gastric pH, free acidity or total acidity in any of the patient groups in pre-and post-anesthesia. 2) In the control group, the mean gastric pH was 1.86+/-0.07, free acidity was 33.48+/-8.73 and total acidity was 49.31+/-9.10. 3) In the group I, the mean gastric pH was 2.62+/-0.24, free acidity was 5.65+/-1.89 and total acidity was 19. 76+/-3.27. Compared with the control group, the gastric pH in group I increased but free acidity and total acidity both decreased significantly(p<0.05). 4) In the group II, the mean gastric pH was 3.46+/-0.52, free acidity was 4.18+/-l.75 and total acidity was 19.76+/-3.27. 5) In the group III, the mean gastric pH was 6.17+/-0.66, free acidity was 10.96+/-4.42. Compared with the control group, the mean gastric pH in group III increased but free acidity and total acidity both decreased significantly(p<0.001).6) In the group IV, the mean gastric pH was 2.70+/-0.39, free acidity 11.01+/-4.73 and total acidity was 33.41+/-5.81. Compared with the control group, the gastric pH in group IV increased but free acidity and total acidity both decreased significantly(p<0.05). So, compared with the control group, the mean gastric pH above 2.5 increased significantly in the all groups. In conclusion, it would seem that the incidence of severe aspiration pneumonitis can be decreased by anticholinergic drugs and cimetidine pretreatment in surgical patients.

MeSH Terms

Anesthesia
Atropine
Cholinergic Antagonists*
Cimetidine
Glycopyrrolate
Humans
Hydrogen-Ion Concentration*
Incidence
Pneumonia
Atropine
Cholinergic Antagonists
Cimetidine
Glycopyrrolate