Incidence of Gastroesophageal Reflux in Dogs Undergoing Orthopaedic Surgery or Endoscopic Evaluation of the Upper Gastrointestinal Tract

Abstract

Gastroesophageal reflux (GER) is a common event during general anaesthesia but is often underdiagnosed in veterinary medicine. The oesophageal pH in anaesthetised dogs undergoing endoscopic evaluation of the upper gastrointestinal tract (END group; n = 12) or orthopaedic surgery (ORT group; n = 12) was measured using an oesophageal probe. The dogs were sedated with acepromazine or with methadone or butorphanol, and anaesthesia was induced with propofol and maintained with isoflurane. Of the 24 dogs in this study, 21 (87.5%) had an episode of GER during anaesthesia. The incidence of GER, as well as the first, the minimum, and the maximum pH values, did not differ significantly between the groups. The mean maximum difference versus the first pH value was higher for dogs in the END group (−2.6 ± 3.5) as compared with those in the ORT group (−0.7 ± 2.5), although they were not statistically significant (p = 0.25). The administration of methadone or butorphanol had no significant effect on the development of acidic reflux or biliary reflux. In the acepromazine-sedated dogs, the incidence of GER did not differ significantly between patients undergoing an endoscopic procedure and those undergoing orthopaedic surgery; however, during endoscopy, fluctuations in the oesophageal pH can be expected, even without any clinical signs of GER.

The Effect of Premedication on the Incidence of Gastroesophageal Reflux in 270 Dogs Undergoing General Anesthesia

“…On the other hand, orthopedic surgeries revealed a 36.6% of GOR (30/82 dogs), with a non- significant difference compared with the other surgical procedures. In veterinary literature, orthopedic surgeries are correlated with a higher risk of regurgitation and reflux [ 18 , 38 , 47 ], nevertheless our findings did not support this correlation. This may be explained by the low doses of opioids used in premedication or by the careful manipulation and minimum changes in recumbency during the procedures.…”

“…In another study 21 out of 24 dogs that were administered either butorphanol or methadone in premedication experienced a reflux episode. Although the exact number of dogs premedicated with butorphanol and refluxed was not clearly stated, the reflux episodes were increased and no statistically significant difference between butorphanol and methadone on the incidence of reflux was detected [ 38 ]. In our study, the use of butorphanol in combination with acepromazine or dexmedetomidine increased the incidence of GOR with the AB group reaching an incidence of 66.7% of reflux and DB group 53.3%.…”

Treatment of Gastroesophageal Reflux Disease in 2 Young Dogs

“…(12). In one study, 50% of dogs developed biliary reflux after undergoing orthopedic surgery, and 33.3% developed acidic reflux (7). In another study, 55.6% of patients undergoing orthopedic surgery had a 26-fold higher probability of passive regurgitation than those who were anesthetized for other diagnostic procedures (6).…”

A Systematic Review of the Methods of Assessment of Gastro-Oesophageal Reflux in Anaesthetized Dogs

“…N/A Measurement every fourth second (frequency 0.25 Hz) Catheter secured to the mandible with adhesive tape. Dogs’ position and duration of anaesthesia recorded [ 4 ] Lambertini et al, 2020 N/A “Reflux of gastric content into the oesophagus” Decrease in oesophageal pH to a value <4.0 (acidic reflux) or as an increase to a value >7.5 (biliary reflux) for at least 30 s Oesophageal pH meter 1. Two-point calibration (buffer solutions pH 4.0 and 7.0) 2.…”

“…The literature highlights several risk factors (i.e., age, body weight, and type of surgery) and reports that the incidence of regurgitation and GOR may be influenced by a number of interventions (i.e., pre-operative fasting, positioning, and drugs). Reported incidences seem to vary reasonably for regurgitation [from 0.96% [ 1 ] to 5.5% [ 2 ],] but enormously for GOR [from 5% [ 3 ] to 87.5% [ 4 ]]. Such a huge variability is rather surprising.…”