Barrier pressure at the gastroesophageal junction in anesthetized dogs

Objective-To evaluate the effect of body position on barrier pressure at th e gastroesophageal junction in anesthetized Greyhounds and to assess altera tions in barrier pressure following gastropexy. Animals-8 adult Greyhounds. Procedure-Barrier pressure at the gastroesophageal junction was measured by fast (1 cm/s) and slow (1 cm/10 s) withdrawal of a subminiature strain gau ge transducer through the gastroesophageal junction in 8 anesthetized dogs. The effect of body position was measured. Each dog then was placed in righ t-lateral recumbency, and gastropexy was performed in the left flank. Addit ional measurements were obtained 1, 5, 10, 20, and 30 minutes after gastrop exy. Results-Barrier pressure for dogs positioned in sternal recumbency (mean +/ - SEM, 1.1 +/- 0.53 mm Hg) was significantly less than for dogs positioned in right lateral or left lateral recumbency. Following gastropexy, there wa s a steady increase in barrier pressure. Thirty minutes after gastropexy, b arrier pressure was significantly higher (13.36 +/- 3.46 mm Hg), compared w ith the value before surgery. Conclusions and Clinical Relevance-Barrier pressure in anesthetized dogs is highly variable and influenced by body position. This is most likely the r esult of anatomic interrelationships between the diaphragm, stomach, and te rminal portion of the esophagus. Gastropexy also increases barrier pressure in the immediate postoperative period, which may be clinically relevant in terms of understanding how resolution of gastroesophageal reflux disease a ssociated with hiatal hernia may be affected by gastropexy combined with he rnia reduction.