The influence of anaesthetic drugs on the lower oesophageal sphincter in propofol/nitrous oxide anaesthetized dogs: Pressure profilometry in an animal model

Abstract

The lower oesophageal sphincter (LES) is the main barrier against gastro-oesophageal reflux. Various anaesthetic drugs have been reported to affect the LES pressure. In this study, the effects of cisapride, atropine, suxamethonium, vecuronium and pancuronium on the LES pressure of six mongrel dogs anaesthetized with propofol and nitrous oxide were investigated. By means of eight-channel pressure profilometry the LES pressure was measured in consecutive sessions before and after administration of each drug. Compared to basal values, atropine and suxamethonium significantly decreased LES pressure, pressure vector volume and sphincter length. Cisapride significantly increased all sphincter parameters, vecuronium significantly increased LES pressure and pressure vector volume while pancuronium had no significant effects. A significant decrease of the LES pressure and pressure vector volume was observed when nitrous oxide was omitted from the ventilation mixture. Three-dimensional imaging showed an asymmetric shape of the LES pressure which resulted from radial differences of the LES pressure. The results from this study show that both the anaesthetic animal model and the eight-channel pressure profilometry are useful procedures in studying the effects on sphincter function of different drugs during anaesthesia.

Life‐threatening pharyngeal oedema secondary to severe perianaesthetic regurgitation in a French bulldog: Management with topical adrenaline and nasotracheal tube

“…Gastroesophageal reflux (GOR) is the outflow of gastric content into the oesophagus and is a common complication of general anaesthesia 1–3 . Previously reported rates vary between 16%−60% 2,3 .…”

“…Gastroesophageal reflux (GOR) is the outflow of gastric content into the oesophagus and is a common complication of general anaesthesia. [1][2][3] Previously reported rates vary between 16%−60%. 2,3 Reported consequences range from postoperative discomfort to oesophagitis or oesophageal stricture.…”

Correlation between Bispectral Index, Observational Sedation Scale, and Lower Esophageal Sphincter Pressure in volunteers using dexmedetomidine or propofol

“…Reduced pressure and consequent reduction in the gastro-esophageal pressure gradient (GEPG) may promote gastro-esophageal reflux, which increases the chances of aspiration, and thus contribute to aspiration pneumonia, pneumonitis, and associated morbidity. Many sedatives and anesthetics reduce lower esophageal sphincter pressure (LESP), but LESP per se is difficult to measure [2–4]. The relationship between sedation level and lower esophageal sphincter functionality is of considerable clinical interest.…”

“…Previous studies have shown a good correlation between anesthetic dose and reduced LESP [2–4], suggesting that there may also be an association between sedation level and LESP. We thus evaluated the association between lower esophageal sphincter pressure and 2 measures of sedation: BIS and the responsiveness component of the Observer’s Assessment of Alertness score.…”