Definition of Dehydration
Dehydration, also known as low circulating blood volume or negative fluid balance, occurs when the body loses more fluid than it takes in. This can happen from decreased fluid intake (in food and water), increased fluid loss (in urine, gastrointestinal and respiratory secretions or blood loss), or both. Things that adversely affect thirst or appetite predispose a dog to dehydration; dogs left outside in hot weather and those with frozen water dishes frequently get dehydrated. Vomiting and diarrhea are common examples of fluid loss leading to dehydration. Dehydration decreases the volume of blood, which reduces oxygen delivery and waste removal. It also imbalances the body’s electrolytes, such as calcium, magnesium, sodium and potassium. Without rehydration, affected dogs can rapidly reach the brink of death. Dogs should have free access to fresh water and should be seen by a veterinarian if they stop eating or have prolonged bouts of vomiting or diarrhea.