Using Intra-arterial tPA for Severe Frostbite Cases. An Observational Comparative Retrospective Study

Abstract

Frostbite causes tissue damage through five major mechanisms, out of which two are amenable to treatment. The first-line treatment is rapid rewarming therapy using water at 40°C to 42°C, which addresses the formation of ice crystals in the intra and extra cellular compartments. The second mechanism is progressive tissue ischemia after rewarming and is only accessible to a second-line therapy represented by thrombolysis. This study aimed to determine the efficacy of thrombolysis. This is a single-center retrospective cohort study, where it was aimed to evaluate two groups of patients. A total of 18 patients were included in this study. Mean times between injury to thrombolytic therapy and admission to thrombolytic therapy was 26.04 hours (SD 13.6) and 9.65 hours (SD 9.89), respectively. All patients suffered injuries ranging from second-degree deep to third degree. The rate of patients having complete, partial, and no angiographic responses were 55.6%, 11.1%, and 33.3%, respectively. The main outcome of interest showed that 11 (61.1%) patients in total had amputations at different levels. Results showed that in the intervention group, five (55.6%) of the patients had amputations compared with six (66.7%) from the control group (P = .6) at comparable levels of amputation. The literature supports that the use of intra-arterial tissue plasminogen activator might be beneficial for severe cases of frostbites; however, it lacks of studies of major significance and results are often controversial. Our study has not shown statistically significant results on amputation levels and cannot support the hypothesis of efficacy of thrombolytic therapy.

Thrombolytic Salvage of the Frostbitten Upper Extremity: A Systematic Review

“…Tables 1 and 2 include the demographic information of the included studies, number of patients, number of patients treated by thrombolysis, methodologic quality, and level of evidence. Four of these articles-1 case series and 3 retrospective cohort studies-combined data between upper extremity and lower extremity frostbite 1,4,17,18 and were only included for qualitative analysis while the remaining 9 articles-1 retrospective cohort study, 3 case series, and 5 case reports-were included for qualitative analysis. [17][18][19][20][21][22][23][24][25][26][27][28][29] The overall level of evidence was IV and the average number of patients per study was 22 (range: 1-102), with a majority of studies being single case reports (Table 1).…”

“…Factors associated with failed thrombolytic salvage were delayed presentations (>24 hours), multiple freeze-thaw cycles, and > 24 hours of warm ischemia. 1,4,17,18,20,21,26,27 Sixteen patients (10%) developed complications. The most common complications were bleeding complications.…”

“…The average level of evidence included is also low, at Level III. The included studies had an average MINORS score of 12.5 (range: [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] which is expected as this review included case reports, case series, and retrospective studies. Another important limitation of our work is that we cannot determine if thrombolysis preserved length of the amputated structures, thereby reducing the functional limitations of the amputations, or if it salvaged the soft tissue reducing the need for soft tissue reconstruction.…”

Exploring the Development of a Canadian Frostbite Care Network and the Future of Frostbite Care in Canada Using a Qualitative Approach

“…These include anti-inflammatories, such as ibuprofen and acetylsalicylic acid (ASA); vasodilators, such as iloprost; thrombolytics, such as recombinant tissue plasminogen activator; and the use of hyperbaric oxygen therapy. 2,4,6,[10][11][12][13][14] While treatment protocols for managing frostbite have been suggested, evaluation of patient outcomes across institutions is challenging because of low patient numbers and diversity in reporting and patient presentation. 4,5,7,8,10,11 These limitations are well recognized and complicated by demographic/geographic factors that may delay initial treatment and make frostbite difficult to study effectively.…”

“…However, studies to date are restricted by small sample sizes, retrospective reviews, case studies, and single-center studies, further compounded by variability in transfer time for patients to receive treatment. [11][12][13]19,20 The transferability of developed protocols is limited due to lack of clear evidence-based treatments, faculty expertise, availability of medications and equipment, limited overall patient numbers, and equivalency of frostbite severity. 7,[11][12][13] Increased participation in extreme adventure sports combined with the growing epidemic of homelessness will heighten frostbite presentation in both large urban centers and resource-limited rural centers.…”