Third-space sequestration is a pathological shift of fluids (water and electrolytes) from the blood and lymphatic circulation to the interstitial compartment, body cavities, or other areas that normally contain a minimal amount of fluid, causing severe metabolic imbalances.
Symptoms and disorders related to this condition are varied and generally quite severe: dehydration, hypotension, edema, pleural or peritoneal effusions, renal or heart failure, muscle weakness, paresis, altered sensorium...
Among the main causes that can lead to "third-space" sequestration, we include those that are obstructive (gastroenteric obstructions, circulatory obstructions), inflammatory/allergic (sepsis, infections, toxic-allergic reactions), osmotic imbalances (hyponatremia, hypokalemia, hypoproteinemia), traumatic or post-surgical.
In bovine medicine, we often encounter similar situations, especially related to gastrointestinal tract pathologies, as in the cow shown below. In these cases, correctly diagnosing the existing metabolic imbalances with a blood gas analysis will be crucial for providing adequate and effective supportive therapy.
This Holstein cow, which calved about 2 weeks ago, has shown a progressive drop in milk production for several days and has completely stopped rumination and feed intake for 24 hours. Upon clinical examination, she exhibits general weakness, an anxious expression, sunken eyes, and a large tympanic area on the left flank due to a left displaced abomasum, likely present for several days.
