Measurement of the length and position of the lower oesophageal sphincter by correlation of external measurements and radiographic estimations in dogs

Abstract

Fifty dogs were investigated in order to correlate the length and position of the lower oesophageal sphincter (LOS) with external measurements. Various external measurements were taken while the dogs were anaesthetised and positioned in lateral recumbency. An oesophageal tube was then introduced into the oesophagus and thoracic radiographs were taken. The 'real internal length of the oesophagus' was calculated as the length from the lower jaw incisor tooth to the position of the oesophageal tube at the costal border of the diaphragm. A highly significant linear correlation was found between this internal length and the external length from lower jaw incisor tooth to the anterior border of the head of the 10th rib. Using oesophageal manometry, the length and position of the LOS was also studied in 25 clinically normal bitches. The mean length of the LOS was found to be 4.6 +/- 0.92 cm. The position of the LOS was a mean of 4.4 +/- 1.69 cm cranial to the costal border of the diaphragm. The findings of this study indicate that the external measurements can be used to position catheters for accurate oesophageal manometry in the dog.

Ambulatory esophageal pHmetry in healthy dogs with and without the influence of general anesthesia

“…To standardize and guarantee the correct positioning of the tip of the catheter, the methodology described by Waterman and Hashim (1991) was used by externally measuring the distance between the mandible incisor teeth and the cranial border of the tenth rib through the angle of the mandible. The measurement was always performed after the preanesthetic medication, and with the animals positioned in left lateral decubitus.…”

“…To standardize and ensure the correct positioning of the catheter, the external body measurement methodology described by Waterman and Hashim (1991) was adapted. A 2.1 mm pHmetry catheter was introduced transnasally.…”

“…To position the catheter correctly, it is necessary to externally measure the distance between the mandible incisor teeth and the cranial border of the 10th rib, through the angle of the mandible, with the sensor being thus located between 2 and 7.5 cm of the esophagogastric junction. Another way to ensure the adequate positioning of the catheter is through a thorax radiographic exam, with its extremity appearing between 2 and 7.5 cm cranial to the costal border of the diaphragm (Waterman and Hashim 1991).…”

Refluxo gastroesofágico em cães anestesiados: fisiopatologia, clínica, diagnóstico e terapêutica

“…Funciona como um esfíncter fisiológico e não como anatômico, pois não é constituído por uma grande massa especializada de músculo e atua como uma zona de alta pressão em descanso, que promove um fluxo unidirecional do esôfago para o estômago, prevenindo assim o refluxo do conteúdo gástrico (WATERMAN & HASHIM, 1991;STROMBECK & GUILFORD, 1996;TAMS, 2005). Em cães, o EEG consiste de uma camada externa longitudinal de músculo estriado e uma camada interna circular de músculo liso, que se funde com a camada interna de músculo estriado do esôfago adjacente (STROMBECK & GUILFORD, 1996;TAMS, 2005).…”

“…Em cães, o EEG consiste de uma camada externa longitudinal de músculo estriado e uma camada interna circular de músculo liso, que se funde com a camada interna de músculo estriado do esôfago adjacente (STROMBECK & GUILFORD, 1996;TAMS, 2005). Um estudo manométrico demonstrou que o EEG nos cães apresenta 4,4±1,69cm de comprimento (WATERMAN & HASHIM, 1991).…”