Gastro-oesophageal reflux in large-sized,deep-chested versus small-sized,barrel-chested dogs undergoing spinal surgery in sternal recumbency

Objective

The aim of this study was to investigate whether an increased frequency of gastro-oesophageal reflux (GOR) is more common in large-sized, deep-chested dogs undergoing spinal surgery in sternal recumbency than in small-sized, barrelchested dogs.

Study design

Prospective, cohort study.

Animals

Nineteen small-sized, barrel-chested dogs (group B) and 26 large-sized, deep-chested dogs (group D).

Methods

All animals were premedicated with intramuscular (IM) acepromazine (0.05 mg kg^?1) and pethidine (3 mg kg^?1) IM. Anaesthesia was induced with intravenous sodium thiopental and maintained with halothane in oxygen. Lower oesophageal pH was monitored continuously after induction of anaesthesia. Gastro-oesophageal reflux was considered to have occurred whenever pH values > 7.5 or < 4 were recorded. If GOR was detected during anaesthesia, measures were taken to avoid aspiration of gastric contents into the lungs and to prevent the development of oesophagitis/oesophageal stricture.

Results

The frequency of GOR during anaesthesia was significantly higher in group D (6/26 dogs; 23.07%) than in group B (0/19 dogs; 0%) (p = 0.032). Signs indicative of aspiration pneumonia, oesophagitis or oesophageal stricture were not reported in any of the GOR cases.

Conclusions and clinical relevance

In large-sized, deep-chested dogs undergoing spinal surgery in sternal recumbency, it would seem prudent to consider measures aimed at preventing GOR and its potentially devastating consequences (oesophagitis/oesophageal stricture, aspiration pneumonia).