Evaluation of the combined effects of atropine and neostigmine on the lower oesophageal sphincter.

The effects, on the lower oesophageal sphincter, of the simultaneous administration of atropine and neostigmine were studied in 10 healthy patients undergoing gynaecological surgery. Atropine 1.2 mg and neostigmine 2.5 mg were given to antagonize neuromuscular blockade at the termination of surgery. For the succeeding 15-20 min, frequent measurements of lower oesophageal sphincter pressure (LOSP) were made whilst anaesthesia was maintained. It was demonstrated that this drug combination resulted in a significant decrease in LOSP initially, but that this potentially deleterious effect was transient in nature.