Fluid therapy is a topic that sometimes gets overlooked by vets, partly because there is a misconception that developing fluid plans can be difficult.
However, if you keep it simple, you can develop a tailored fluid therapy plan for you patient that is much better than a blanket “twice maintenance” rate.
There are four basic components to a fluid therapy plan that you need to think about:
Perfusion deficits need to be corrected immediately.
Start with a 10mls/kg IV fluid bolus of buffered crystalloids and repeat as necessary up to shock volumes (60mls/kg for cats, 90mls/kg for dogs) until clinical parameters improve.
Once you have corrected your perfusion deficits, then you start correcting dehydration deficits.
Correction of dehydration is general done over a course of 24 hours.
Maintenance requirements are fairly standard and formulas are readily available in many sources.
Determining ongoing losses can be a bit tricky, but you need to try your best to include this in the fluid plan.
Patients that are vomiting, have diarrhoea, polyuria etc, will need extra fluid to cover for ongoing losses. These losses can be measured by weighing the faeces, weighing absorbent bedding if the patient has urinated on it, or by rough estimation.
So, when taking these four components of a fluid therapy plan into account, you’ll soon see that, frequently, twice maintenance is not enough.
The final and most important part of every fluid therapy plan is reassessment. Reassess your patient every couple hours to determine if your plan is appropriate and adjust accordingly.
- Tip of the Week author Gerardo Poli is the author of The MiniVet Guide to Companion Animal Medicine.