Developments in surgical fluid therapy rates in veterinary medicine

Kristina Naden

doi:10.18849/ve.v5i3.299

Abstract

PICO question Is there sufficient evidence to show surgical fluid therapy delivered at the recommended 3 mL/kg/hour for cats and 5 mL/kg/hour for dogs leads to a better outcome compared with widely accepted rates of 10 mL/kg/hour for both cats and dogs?  Clinical bottom line Category of research question Treatment The number and type of study designs reviewed Five studies were appraised. Two of these were opinion pieces, with one non-comparative prospective study, one randomised controlled trial, and one case control study. Strength of evidence Weak Outcomes reported Currently there is limited evidence to show that the surgical fluid therapy recommendations made by the 2013 Journal of the American Animal Hospital Association guidelines (Davis et al., 2013) for cats and dogs lead to a better outcome than accepted fluid therapy rates used. Fluid overload in humans can cause long-term adverse effects, however the same effects have yet to be shown specifically in veterinary patients Conclusion No evidence was found that provides strong, conclusive evidence that the 2013 recommendations by the American Animal Hospital Association and American Association of Feline Practitioners leads to a better outcome for both cats and dogs. The resulting research outlined below identifies a need to conduct clinical studies on the effects of fluid therapy on cats and dogs, and identify clear monitoring protocols to minimise and ideally avoid, fluid overload. When adequate, valid clinical studies have been carried out, this will provide sufficient information for the development of evidence-based recommended rates of fluid therapy for veterinary medicine, in a range of contexts  How to apply this evidence in practice The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources. Knowledge Summaries are a resource to help reinforce or inform decision-making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care. 

Highlights

Fluid therapy should be individualised for each patient Fluid selection may need to be adjusted from one type of fluid to another during hospitalisation While blood pressure is often used to assess tissue perfusion, intraoperative hypotension may not always be related to dehydration
This study focused on feline deaths in clinical practice, due to anaesthetic complications, with limited data provided on fluid therapy
Davis et al (2013) recommended the following: provide maintenance rate plus necessary replacement at less than 10 mL/kg/hour; adjust fluid rates based on patient assessment and monitoring; patients with cardiovascular disease and renal disease should be administered a lower rate of fluid; and rates should be decreased if anaesthesia is more than one hour, with suggested reduction to be 25% per hour until fluid is being delivered at maintenance rate

Summary

A Knowledge Summary by Kristina Naden BVN1*

Current trend in veterinary surgical practice is to provide a generic rate of fluid therapy for a range of surgical procedures (Davis et al, 2013) This may vary in clinics where blood pressure, (in addition to other more standard parameters such as heart rate, and respiratory rate) is monitored intraoperatively, with fluid therapy levels adjusted in response to variance in this parameter While Gurney (2018) does not recommend specifics around fluid therapy, it is noted that overload of fluids be avoided, and the GDT approach be used in veterinary medicine, in order to avoid postoperative complications This limited amount of evidence suggests further research is required to identify the impact of current recommendations for fluid therapy in cats and dogs

Summary of the evidence

Limitations

Findings

Methodology Section