Vetgirl Veterinary Continuing Education Podcasts

In today's VETgirl podcast, we review the importance of performing a venous blood gas in the vomiting patient. Why? Because when we see a hypochloremic, hypokalemic metabolic alkalosis, we should be ruling out an obstructive gastrointestinal (GI) foreign body. Previously, the presence of a metabolic alkalosis has been associated with a upper GI (e.g., pyloric) foreign body. Why? Because of protracted vomiting and loss of chloride, which deletes the body of an anion. In order to maintain electroneutrality, when a sodium (Na+) moves, a negatively charged anion must exchange with it. While this is typically chloride, if the body is chloride deplete, it absorbs bicarbonate (HCO3-) instead, resulting in the classic metabolic alkalosis. Normally, dogs reabsorb 98% of their gastrointestinal secretions per day. Once a GI obstruction is present for more than 24 hours, resorption in the bowel proximal to an obstruction results in increased secretion of Na+, K+, and water into the lumen. Historically, proximal GI obstru