Frostbite is a common reason for emergency department (ED) presentations in Canada. Iloprost, a prostacyclin analogue, has been investigated to reduce the risk of amputation with its use expanding. Two Canadian cities implemented iloprost over different times leading to a practice variation that allowed for treatment comparison. Our objective is to evaluate the effectiveness of iloprost compared with non-iloprost treatment. Secondary objectives include assessing the impact of iloprost dosage and homelessness.

A retrospective cohort study was conducted on adult severe frostbite cases presenting to EDs in Calgary and Edmonton between November 2021 and April 2024. Data were abstracted from clinical databases and analysed for demographic and injury characteristics, treatment and amputation outcomes.

Of 1812 total ED encounters for frostbite, 257 patients with grades 2–4 extremity frostbite were included for analysis. Logistic regression found that overall patients receiving iloprost were associated with reduced likelihood of any amputation (OR=0.49, 95% CI 0.25 to 0.96) and fewer digit amputations (p

Iloprost infusion was associated with a reduction in amputation rates in grade 3 and 4 frostbite with the greatest association seen in grade 3 cases. Greater iloprost dosage was associated with improved digit salvage. Homelessness was associated with delayed ED presentation.