About this Calculator
This free water deficit calculator is designed to assist veterinarians in estimating the volume of free water required to safely correct hypernatremia in dogs and cats using the following formula:
Deficit = [(Patient Na / Desired Na) – 1] x 0.6 x Weight (kg)
This formula calculates the volume of free water needed based on the patient’s sodium levels and body weight.
Patient Na: Current plasma sodium concentration
Desired Na: Target plasma sodium concentration
Weight (kg): The patient’s body weight
Key Considerations
This formula does not account for ongoing free water losses, which is critical for patients with conditions like diabetes insipidus, where water retention is impaired. Monitoring sodium every 4-6 hours and adjusting the water intake accordingly is vital to ensure an appropriate and safe sodium decrement.
For more details on managing hypernatremia, explore this blog post.
VetEmCrit Academy is dedicated to providing veterinarians with cutting-edge resources and evidence-based tools for managing electrolyte and acid-base disorders. Whether you’re treating common electrolyte imbalances or tackling complex cases, VetEmCrit Academy offers guidance that helps clinicians progress from novice to expert. With practical tools like this calculator and case-based learning, the academy supports continuous education and improved patient care.