Effectiveness of intravenous prostaglandin to reduce digital amputations from frostbite: an observational study

We assessed the effectiveness and safety of a 5-day intravenous prostaglandin (iloprost) protocol at reducing digital amputation for patients with severe frostbite injuries at urban emergency departments.

This retrospective study examines consecutive patients who presented to Calgary emergency departments from April 2017 to April 2020 with Grade 2-4 frostbite injuries. Patients from February 2019 onward were managed using a 5-day iloprost infusion protocol, whereas patients prior to this time were managed with standard care (local best practice without iloprost as a therapeutic option). The primary effectiveness outcome was rate of affected digits amputated, stratified by frostbite severity. The secondary safety outcome was the incidence of serious adverse events associated with iloprost (allergic reactions or symptomatic hypotension requiring treatment or discontinuation of the infusion).

90 patients were included, 26 were treated with iloprost, compared to 64 patients who received usual care. Both the treatment and usual care groups experienced substantial rates of homelessness and substance use. No digital amputations were required for patients with Grade 2 injuries in either group, but significantly lower digital amputation rates were observed for patients with more severe frostbite injuries treated with iloprost versus usual care: Grade 3 (18% vs 44%, p < 0.001), Grade 4 (46% vs 95%, p < 0.001). No serious adverse events were associated with iloprost.

In this unselected socially complex urban population, administration of iloprost for patients with frostbite was shown to be safe and was associated with lower digital amputation rates, particularly for those with more severe injuries.