For decades the technique of “sweating a leg” has been a mainstay in conservative management of equine leg injuries, as well as improving cosmetic appearance in certain situations. While topical medications and application techniques vary greatly, all sweats have three common ingredients:
- A topical medication consisting of a base (traditionally nitrofurazone, or Fura-Zone, ointment) often mixed with various additives, most commonly an anti-inflammatory (a steroid such as dexamethasone or a non-steroidal anti-inflammatory such as diclofenac), and dimethyl sulfoxide (DMSO) as a carrying agent.
- Plastic wrap.
- A firmly applied stable bandage.
The purpose of a sweat is to apply moist heat and compression to a structure to increase the tissue temperature, stimulate circulation, and aid in the removal of edema (fluid swelling). Edema occurs when the fluid that naturally leaks from blood vessels is not effectively carried away by the lymphatic system, due to poor circulation or conditions in which excess fluid leakage overcomes normal lymphatic return capacity. The nitrofurazone (or other base ingredient) creates a moist environment, while the DMSO stimulates blood flow and helps carry any other medications in the mixture into the tissues. Saran or other plastic wrap helps keep the area moist and warm, while the stable bandage helps further retain heat and compresses the swollen tissues to help the lymphatic system clear up excess extracellular fluid.
Sweating is best used once the acute stage of inflammation has resolved, since you do not want to add further heat to freshly damaged tissue. Ice and cooling clay poultices are more appropriate choices in those initial stages. Once things have settled down and healing has begun, you can use a sweat to reduce edema, encourage circulation, and aid absorption of topical medication. Ask your veterinarian when it’s appropriate to start sweating—usually when there’s no obvious heat in the affected Current magazine subscribers can click here to and continue reading.
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