Acid-base and electrolyte evaluation in dogs with upper GI obstruction: 115 dogs (2015-2021)

Area of Science:

• Veterinary Medicine
• Internal Medicine
• Critical Care

Background:

• Metabolic alkalosis is an uncommon condition in small animals.
• It has been previously associated with gastrointestinal obstructions in dogs.
• Reported prevalence of metabolic alkalosis in canine patients ranges from 2% to 45%.

Purpose of the Study:

• To determine the prevalence of metabolic alkalosis in dogs with upper gastrointestinal obstruction.
• To identify other acid-base and electrolyte disorders in this patient population.
• To compare pre- and post-operative acid-base status.

Main Methods:

• Retrospective review of electronic medical records from January 2015 to October 2021.
• Inclusion criteria: dogs presenting with vomiting and evidence of upper gastrointestinal obstruction, with preoperative venous blood gas analysis.
• Acid-base status determined using traditional analysis; post-operative status compared to preoperative results.

Main Results:

• Twenty-two percent (25/115) of dogs had metabolic alkalosis or mixed acid-base disturbance preoperatively.
• Metabolic alkalosis resolved post-operatively in nearly all patients.
• Common preoperative electrolyte derangements included hypokalaemia (64.4%), hypochloraemia (72.8%), and hyponatraemia (77.4%).

Conclusions:

• The prevalence of preoperative metabolic alkalosis in dogs with upper gastrointestinal obstruction is lower than previously reported.
• Surgical or endoscopic alleviation of the obstruction effectively resolves metabolic alkalosis.
• Upper gastrointestinal obstruction is associated with significant electrolyte derangements.