Case Report: Severe Frostbite in Extreme Altitude Climbers—The Kathmandu Iloprost Experience

Abstract

Severe frostbite occurs frequently at extreme altitude in the Himalayas, often resulting in amputations. Recent advances in treatment of frostbite injuries with either intravenous or intra-arterial tissue plasminogen activator, or with iloprost, have improved outcomes in frostbite injuries, but only if the patient has access to these within 24 to 48 h postinjury, and ideally even sooner. Frostbitten Himalayan climbers are seldom able to reach medical care in this time frame. We wished to see if delayed iloprost use (up to 72 h) would help reduce tissue loss in grade 3 to 4 frostbite. In a series of 5 consecutive climbers with severe frostbite in whom we used iloprost, 4 of whom received treatment between 48 and 72 h from injury, 2 had excellent results with minimal tissue loss, and 2 had good results with tissue loss less than expected. The 1 patient with a poor outcome likely experienced a freeze-thaw-refreeze injury. This small series suggests that iloprost can be beneficial for severe frostbite, even after the standard 48-h window and perhaps for up to 72 h.

Management of severe frostbite with iloprost, alteplase and heparin: a Yukon case series

“…23 Iloprost can be used in patients with any level of cyanosis and risk of digit loss (grade 2-4 frostbite), and can be effective up to 72 hours after rewarming. 24 Iloprost is not currently available commercially in Canada and can be obtained only through Health Canada's Special Access Programme. We identified a single published case report on the use of the prostacyclin epoprostenol in a patient with frostbite, at a US institution without access to iloprost.…”

“…Beginning in the 1990s, a growing body of evidence has popularized the use of iloprost in frostbite, first in Europe and now in Canada. 6,11,15,16,21,24,27 Iloprost, a synthetic prostacyclin analogue, is a potent vasodilator that inhibits platelet aggregation and enhances fibrinolytic activity by releasing endogenous tissue plasminogen activator. 29 To our knowledge, there is a single randomized controlled trial published to date showing the benefit of iloprost combined to alteplase and heparin.…”

Amputation Risk Factors in Severely Frostbitten Patients

“…The time to reach a clinical setting in order to receive advanced treatments (e.g., intravenous vasodilators or thrombolytic agents) was not considered in this study as none of the subjects received them. However, evidence suggests that reducing the time lapse before reaching an advanced medical post with possibilities of receiving more complex treatments such as thrombolytic factors and/or vasodilator iloprost in an adequate time frame may decrease the risk of amputation [12,23,24]. Nonetheless, more research is needed to evaluate the real impact of these therapies on frostbite sequelae.…”

Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Frostbite: 2019 Update

“…Despite the limitations of these initial studies, iloprost has shown consistently favorable effects. 73 Extending the treatment window, Pandey et al 74 reported good results with iloprost therapy up to 72 h after injury. In 5 Himalayan climbers with 34 digits at risk, 5 d of daily iloprost infusion produced excellent outcomes in 4 of 5 patients.…”

“…Evidence supports use of heparin as adjunctive therapy in tPA protocols, as described previously. Heparin has been used in conjunction with iloprost as well; the 5 patients in the 1994 Groechenig iloprost study, 71 the 1 Israeli traveler with excellent outcome in the Kathmandu study, 74 and 4 patients in the Finnish study 55 were treated with low molecular weight heparin (enoxaparin) in addition to iloprost. Whether low molecular weight heparin offers additional benefit when combined with iloprost requires further investigation; currently data are insufficient for a recommendation on this combination.…”