Evaluation of digital cryotherapy using a commercially available sleeve style ice boot in healthy horses and horses receiving i.v. endotoxin.
BACKGROUND
Continuous digital cryotherapy experimentally prevents development and reduces severity of sepsis-associated laminitis. A sleeve style ice boot where ice is in direct contact with the skin, and water drains from the boot is being used clinically for distal limb cryotherapy. The degree of cooling achieved by this boot is unknown.


OBJECTIVES
Evaluate skin and lamellar cooling after application of the ice sleeve in healthy horses, and the same horses during an endotoxaemia model.


STUDY DESIGN
Prospective study, crossover design.


METHODS
In eight healthy horses thermocouples were inserted into dorsal lamellae of both front feet, and under skin on both metacarpi. One forelimb received cryotherapy using sleeve style ice boot, with contralateral limb as control. Temperature was recorded on data logging devices at 5 min intervals during each cryotherapy session. Day 1: temperature data was collected for healthy horses. Day 2: data was collected for the same horses during i.v. administration of endotoxin.


RESULTS
In healthy and endotoxaemic horses, the sleeve style ice boot significantly decreased mean skin (7.2°C and 5.8°C respectively) and lamellar (10.8°C and 9.6°C respectively) temperatures compared with control limbs (P<0.001). Skin and lamellar temperatures in endotoxaemic horses undergoing cryotherapy were significantly colder than in healthy horses (P = 0.01).


MAIN LIMITATIONS
Order of treatment not randomised.


CONCLUSIONS
The boot caused significant decreases in lamellar temperatures compared with untreated control limbs in all horses. Endotoxaemic horses had significantly colder lamellae and skin than healthy horses. This study is the first to show that a sleeve style boot, where ice does not cover the hoof, can cause significant decreases in lamellar temperatures through cooling of blood as it travels to the foot.
['Burke|M J|MJ|http://orcid.org/0000-0002-2491-5745', 'Tomlinson|J E|JE|', 'Blikslager|A T|AT|', 'Johnson|A L|AL|', 'Dallap-Schaer|B L|BL|']
D000818:Animals D018592:Cross-Over Studies D017679:Cryotherapy D004731:Endotoxins D005260:Female D005534:Foot Diseases D005552:Forelimb D006724:Hoof and Claw D006734:Horse Diseases D006736:Horses D008297:Male D011446:Prospective Studies D011897:Random Allocation D012881:Skin Temperature
digital cryotherapy horse sepsis-associated laminitis lamellar temperatures sleeve-style ice boot