The use of intravenous tPA for the treatment of severe frostbite

Frostbite in the Pediatric Population: A Comprehensive Review and a Prospective Canadian Survey

INTRODUCTION

Frostbite in the pediatric population, where skeletal maturity has not been achieved, can have important repercussions on subsequent growth. Yet, the optimal management of frostbite injuries in children remains vague. This review aims to summarize the current evidence for frostbite management in children and understand Canadian practice trends on this topic.

METHODS

A review using Medline, Scopus, Web of Science, and gray literature was performed to identify relevant literature on the clinical manifestations, diagnostic methods, and treatment options in pediatric frostbite. An online survey was sent to plastic surgeons through the Canadian Society of Plastic Surgeons (CSPS) mailing list to further identify national practices and trends for pediatric frostbite management.

RESULTS

A total of 109 articles were reviewed. No article provided a specific algorithm for pediatric frostbite, with existing recommendations suggesting the use of adult guidelines for treating children. Our survey yielded 9 responses and highlighted the rarity of pediatric frostbite cases, with no responder treating more than 10 cases per year. Most (55.6%) do not use a pediatric-specific treatment algorithm, whereas 30% apply adult guidelines. A conservative approach focusing on rewarming (55.6%), limb elevation (50%), and tetanus status verification (66.7%) was predominant. Imaging and surgical interventions seem to be reserved for severe cases.

CONCLUSIONS

The current literature for pediatric frostbite management lacks specificity. Canadian practices vary, with a trend toward a conservative approach. The limited evidence and rarity of experience highlight the need for further research, ideally in a collaborative multicentric manner, to create a consensus for pediatric frostbite care.

Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Frostbite: 2024 Update

The Wilderness Medical Society convened an expert panel to develop a set of evidence-based guidelines for the prevention and treatment of frostbite. We present a review of pertinent pathophysiology. We then discuss primary and secondary prevention measures and therapeutic management. Recommendations are made regarding each treatment and its role in management. These recommendations are graded on the basis of the quality of supporting evidence and balance between the benefits and risks or burdens for each modality according to methodology stipulated by the American College of Chest Physicians. This is an updated version of the guidelines published in 2019.

American Burn Association Clinical Practice Guidelines on the Treatment of Severe Frostbite

This Clinical Practice Guideline addresses severe frostbite treatment. We defined severe frostbite as atmospheric cooling that results in a perfusion deficit to the extremities. We limited our review to adults and excluded cold contact or rapid freeze injuries that resulted in isolated devitalized tissue. After developing population, intervention, comparator, outcomes (PICO) questions, a comprehensive literature search was conducted with the help of a professional medical librarian. Available literature was reviewed and systematically evaluated. Recommendations based on the available scientific evidence were formulated through consensus of a multidisciplinary committee. We conditionally recommend the use of rapid rewarming in a 38 to 42°C water bath and the use of thrombolytics for fewer amputations and/or a more distal level of amputation. We conditionally recommend the use of "early" administration of thrombolytics (≤12 hours from rewarming) compared to "later" administration of thrombolytics for fewer amputations and/or a more distal level of amputation. No recommendation could be formed on the use of vascular imaging studies to determine the use of and/or the time to initiate thrombolytic therapy. No recommendation could be formed on the use of intravenous thrombolytics compared to the use of intra-arterial thrombolytics on fewer amputations and/or a more distal level of amputation. No recommendation could be formed on the use of iloprost resulting in fewer amputations and/or more distal levels of amputation. No recommendation could be formed on the use of diagnostic imaging modalities for surgical planning on fewer amputations, a more distal level of amputation, or earlier timing of amputation.

Frostbite treatment: a systematic review with meta-analyses

INTRODUCTION

Our objective was to perform a systematic review of the outcomes of various frostbite treatments to determine which treatments are effective. We also planned to perform meta-analyses of the outcomes of individual treatments for which suitable data were available.

MAIN BODY

We performed a systematic review and meta-analyses in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We searched PubMed, Cochrane Trials, and EMBase to identify primary references from January 1, 1900, to June 18, 2022. After eliminating duplicates, we screened abstracts to identify eligible studies containing information on treatment and outcomes of Grade 2 to 4 frostbite. We performed meta-analyses of groups of articles that provided sufficient data. We registered our review in the prospective registry of systematic reviews PROSPERO (Nr. 293,693). We identified 4,835 potentially relevant studies. We excluded 4,610 studies after abstract screening. We evaluated the full text of the remaining 225 studies, excluding 154. Ultimately, we included 71 articles with 978 cases of frostbite originating from 1 randomized controlled trial, 20 cohort studies and 51 case reports. We found wide variations in classifications of treatments and outcomes. The two meta-analyses we performed both found that patients treated with thrombolytics within 24 h had better outcomes than patients treated with other modalities. The one randomized controlled trial found that the prostacyclin analog iloprost was beneficial in severe frostbite if administered within 48 h.

CONCLUSIONS

Iloprost and thrombolysis may be beneficial for treating frostbite. The effectiveness of other commonly used treatments has not been validated. More prospective data from clinical trials or an international registry may help to inform optimal treatment.

The Effects of Recombinant Human Granulocyte-Macrophage Colony-Stimulating Factor Gel on Third-Degree Frostbite Wounds in Northeastern China: A Randomized Controlled Trial

The aim of the study was to investigate the effects of the rhGM-CSF gel on third-degree frostbite wounds. Sixty-two patients who had suffered third-degree frostbite on their hand or foot (91 wounds in total) were selected using a convenience sampling method and randomly allocated to two groups: the rhGM-CSF group(31patients,45 frostbite wounds) received the rhGM-CSF gel when wound dressing change daily; however, the control group (31patients, 46 frostbite wounds) received aloe glue. The wound healing time, the score of inflammation about the wound and the positive bacterial culture of wound secretions were used to measure outcomes, respectively. Data were analyzed using SPSS (25.0), Student's t test or Mann-Whitney U test and chi-square test or Fisher exact test were selected, as appropriate. The healing time of the rhGM-CSF group was (12.2 ± 5.0) days, which was significantly shorter than that of the control group (15.5 ± 4.7) days (P < .0001). The rhGM-CSF group's wound inflammation scores on the 7th and 14th day of treatment were (0.96 ± 0.21) and (1.88 ± 0.29), respectively, which were better than those of the control group (1.12 ± 0.24) and (1.38 ± 0.15) (both P < .0001). The positive bacterial culture of wound secretions in the rhGM-CSF group was also better than that in the control group on the 3rd, 7th, and 14th day after treatment (P = .027, .004, .030, respectively). According to the results, using rhGM-CSF gel considerably increases the speed of frostbite wounds healing, and have an effect on protecting third-degree frostbite wounds regarding the positive effects. Trial Registration: This trial was registered in the Chinese Clinical Trial Register, ChiCTR1900021299.

Thermal Injuries Occurring to the Foot: A Review

Thermal injuries are one of the most common injuries in both civilian and combat scenarios. The importance of clinical determination of burn and frostbite injuries and treatment involves understanding the pathophysiology and mechanisms of these injuries while continually reviewing literature and studying new treatment modalities. This present review examines the (1) epidemiology, (2) etiology, (3) pathophysiology and classification, and (4) treatment of thermal injuries occurring to the foot. In addition to the paucity of new literature and studies on thermal injury, this is the first review, to the best of our knowledge, to examine the management of thermal injuries occurring to the foot.

The Effects Of Rapid Rewarming On Tissue Salvage In Severe Frostbite Injury

Frostbite is a high morbidity injury caused by soft tissue freezing, which can lead to digit necrosis requiring amputation. Rapid rewarming is a first line treatment method that involves placing affected digits into a warm water bath. This study aims to assess the clinical practices for frostbite at facilities outside of dedicated burn centers, and any impact these practices have on tissue salvage. Retrospective chart review at a single burn center identified frostbite patients admitted directly or as transfers over a seven-year period. Records were reviewed to identify initial treatment strategies. If given, time to thrombolytics from admit was noted. Tissue salvage rates were calculated from radiologically derived tissue at-risk scores and final amputation scores. One-hundred patients were transferred from outside facilities, and 108 were direct admissions (N=208). There was no significant difference in group demographics. Rapid rewarming was the initial treatment modality more commonly in direct admit patients (P=0.016). The use of rapid rewarming did not correlate with tissue salvage (P=0.112). Early use of thrombolytics had a positive impact on tissue salvage (P=0.003). Thrombolytics were given 1.2 hours earlier in direct admit patients (P=0.029), however there was no difference in tissue salvage rates between the groups (P=0.127). Efforts should focus on larger scale study to further assess the effectiveness of rapid rewarming. Although rapid rewarming did not significantly impact tissue salvage in this study, we continue to recommend its use over less studied treatment methods, and continue to view it as an important bridge to burn center transfer and administration of thrombolytic therapy.

Thrombolytic Use in Management of Frostbite Injuries: Eight Year Retrospective Review at a Single Institution

Frostbite injuries are uncommon, understudied, and lack standardized treatment protocols. Although thrombolytics are commonly used, their efficacy remains controversial. Herein, we report the results of a retrospective review of frostbite treatment practices at a single institution. The impact of thrombolytics on outcomes was evaluated. Medical records of frostbite patients admitted between January 2010 and April 2018 were reviewed. Demographics, injury details, treatment, and outcomes were collected. Descriptive statistics were obtained. A case-control analysis comparing patients who received tissue plasminogen activator (tPA) with those who did not was performed. A total of 102 patients were included. The mean age was 43 ± 17.7; 82.4% were male. About 13% of patients were presented with first-degree, 54% with second-degree, 29% with third-degree, and 5% with fourth-degree frostbite. Toes (69%), fingers (53%), and feet (43%) were most commonly affected. Thirteen patients had angiograms. Twelve patients received tPA: three systemic tPA and nine catheter-directed tPA. Overall, 32 patients (31%) required surgery and 27 (26.5%) patients required amputation with an average of 6.5 digits amputated. Digit salvage rate based on angiography was 84.7%. Length of stay (P = .046), number of operations (P = .037), and need for surgery (P = .030) were significantly lower for patients who received thrombolytics. Two patients had bleeding complications but did not require intervention or interruption of therapy. Despite its small sample size, our study suggests benefits from thrombolytic therapy. Prospective, well designed, and multi-institutional studies are warranted to establish evidence-based treatment guidelines for the management of frostbite injuries.

Acute Management of Thermal Hand Burns in Adults: A 10-Year Review of the Literature

INTRODUCTION

Advances in the evidence base of acute thermal hand burns help to guide the management of these common injuries. The aim of this literature review was to evaluate recent evidence in the field over 10 years.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols methodology was used as a guide for this literature review. PubMed, MEDLINE, EMBASE, CINAHL, and Google Scholar were searched for English language articles related to hand burns published between 2009 and 2018 inclusive, and the Cochrane Library was reviewed. Exclusion criteria were as follows: participants younger than 18 years, scar or contracture management, rehabilitation, outcomes assessment, late reconstruction, and electrical or chemical burns.

RESULTS

An initial search retrieved 6493 articles, which was narrowed to 403 full-text articles that were reviewed independently by 3 of the authors and categorized. Of 202 included articles, there were 8 randomized controlled trials and 2 systematic reviews. Six evidence-based guidelines were reviewed. Referral of hand burns to specialist centers, use of telemedicine, early excision and grafting, and immediate static splintage have been recommended. Enzymatic debridement results in earlier intervention, more accurate burn assessment, preservation of vital tissue, and fewer skin grafts, and ideally requires regional anesthesia. Guidance on escharotomy emphasizes indication, technique and adequate intervention, and potential for enzymatic debridement. Inclusion of topical negative pressure, dermal regenerative templates, acellular dermal matrices, and noncellular skin substitutes in management has helped improve scar and functional outcomes.

DISCUSSION

The results of this literature review demonstrate that multiple national and international societies have published burns guidelines during the decade studied, with aspects directly relevant to hand burns, including the International Society for Burn Injuries guidelines. There are opportunities for evidence-based quality improvement across the field of hand burns in many centers.

CONCLUSIONS

More than 200 articles globally in 10 years outline advances in the understanding of acute management of thermal hand burns. Incorporating the evidence base into practice may facilitate optimization of triage referral pathways and acute management for hand burns.

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

BACKGROUND

We identified the need to modernize frostbite management in our northern centre and implemented a treatment protocol in 2015. Our aim was to describe the clinical course of patients presenting to the hospital since the implementation of the protocol.

METHODS

This was a retrospective case series from Whitehorse General Hospital, Whitehorse, Yukon Territory, Canada. We reviewed the charts of patients who presented to the hospital with grade 2-4 frostbite and were treated as per our protocol between Feb. 9, 2015, and Feb. 8, 2020. Patients with grade 2-4 frostbite received iloprost; in addition, those with grade 4 frostbite received alteplase and heparin. We determined the number of digits affected and salvaged, and the time from presentation to the emergency department to treatment initiation. We also examined patients' demographic characteristics, predisposing events, frostbite severity and adverse drug reactions.

RESULTS

In 22 patients treated for grade 2-4 frostbite, 142 digits were affected: 59 with grade 2 frostbite, 25 with grade 3 frostbite and 58 with grade 4 frostbite; of the 142, 113 (79.6%) were salvaged. All 29 digits amputated had grade 4 frostbite. The mean time from presentation to iloprost initiation was reduced from 32.9 hours in 2015 to 3.0 hours in 2020. Sports (10 cases [45%]) and alcohol use (6 [27%]) were the most common precipitating events, with alcohol use tending to result in more severe injury (grade 4 in 5 of 6 cases). Adverse reactions with iloprost (e.g., headache) were common but mild. Adverse reactions with alteplase (e.g., bleeding) were less common but of greater clinical significance.

INTERPRETATION

Over the study period, our protocol contributed to improvement in frostbite care at our institution, resulting in a digit salvage rate comparable to other published results. Our 5-year experience shows that advanced medical care of frostbite can be achieved, even at a rural centre.

Remote delivery of thrombolytics prior to transfer to a regional burn center for tissue salvage in frostbite: A single center experience of 199 patients

While much has been published on efficacy and safety of systemic thrombolytics in the treatment of acute frostbite, there has been limited investigation into administration outside a tertiary care setting. Here, we present a single-center experience with remote initiation of intravenous tissue plasminogen activator (tPA) at referring hospitals prior to transfer to a regional burn center. A modified Hennepin Quantification Score based on tissue involvement was used to determine eligibility for tPA and to quantify severity of amputation. This is a retrospective review of patients with acute frostbite of the digits admitted to a single verified burn center over a five-year period. Of 199 patient admissions, 40 received tPA remotely pre-transfer, 32 received tPA on admission to our institution, and 127 patients did not qualify for tPA therapy according to the protocol. Comparing patients who required any amputation (n=99, 49.7%) to those who did not, patients who received remote tPA had lower odds of any amputation compared to both those receiving tPA at our institution (OR 0.19, 95% CI 0.05 - 0.65, p=0.01) and the group receiving no tPA (OR 0.14, 95% CI 0.05 - 0.40, p<0.001) after controlling for confounders. Only one patient receiving pre-transfer tPA according to protocol (2.3%) had a significant bleeding event requiring transfusion. These results support the protocolized use of thrombolytic therapy for frostbite prior to transfer to a tertiary center.

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

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.

Compartment syndrome following use of tissue plasminogen activator for frostbite in the setting of concomitant diaphyseal tibia fracture

Background:

Tissue plasminogen activator (tPA) is a thrombolytic agent increasingly being employed for the treatment of acute frostbite. Although tPA has been shown with success to increase digit salvage rates, data on potential complications, including risk of hemorrhage, is limited. As a result, acute trauma is considered a contraindication to use in many institution-based protocols. Currently, there is a paucity in the literature regarding use of tPA for frostbite in patients with concomitant extremity fractures.

Case presentation:

We report the case of a 36-year-old male treated with tPA for frostbite to digits of his bilateral hands in the setting of a concomitant diaphyseal tibia fracture. He subsequently developed acute compartment syndrome in his lower extremity. This was followed by emergent fasciotomy and staged fracture fixation with serial wound debridement and subsequent closure. Despite this complication, the patient went on to early radiographic and clinical union of his tibia fracture. His frostbite wounds healed without functional deficits.

Conclusions:

In patients with severe frostbite injury with digital perfusion defects, tPA for thrombolysis may be indicated. Use of thrombolytics for frostbite in trauma patients or those with concomitant extremity fractures requires a multidisciplinary discussion regarding potential risks. Contingency planning is essential to ensure that potential bleeding complications, including development of compartment syndrome, are diagnosed and treated early. Given the paucity in the current literature regarding use of thrombolytics in trauma patients, further study is warranted to inform the surgical community on instances in which the benefits of tPA administration may outweigh the risks.

Level of evidence:

Case report; Level V.

Protocoled thrombolytic therapy for frostbite improves phalangeal salvage rates

Background

Frostbite is a cold injury that has the potential to cause considerable morbidity and long-term disability. Despite the complexity of these patients, diagnostic and treatment practices lack standardization. Thrombolytic therapy has emerged as a promising treatment modality, demonstrating impressive digit salvage rates. We review our experience with thrombolytic therapy for severe upper extremity frostbite.

Methods

Retrospective data on all frostbite patients evaluated at our institution from December 2017 to March 2018 was collected. A subgroup of patients with severe frostbite treated with intra-arterial thrombolytic therapy (IATT) were analysed.

Results

Of the 17 frostbite patients treated at our institution, 14 (82%) were male and the median age was 31 (range: 19–73). Substance misuse was involved in a majority of the cases (58.8%). Five (29.4%) patients with severe frostbite met inclusion criteria for IATT and the remaining patients were treated conservatively. Angiography demonstrated a 74.5% improvement in perfusion after tissue plasminogen activator thrombolysis. When comparing phalanges at risk on initial angiography to phalanges undergoing amputation, the phalangeal salvage rate was 83.3% and the digit salvage rate was 80%. Complications associated with IATT included groin hematoma, pseudoaneurysm and retroperitoneal hematoma.

Conclusions

Thrombolytic therapy has the potential to greatly improve limb salvage and functional recovery after severe frostbite when treated at an institution that can offer comprehensive, protocoled thrombolytic therapy. A multi-center prospective study is warranted to elucidate the optimal treatment strategy in severe frostbite.

Guidelines for Thrombolytic Therapy for Frostbite

The data are insufficient to support standardized treatment of all patients with frostbite with thrombolytic therapy. The following guidelines, however, should be applied to all patients with cyanosis persisting proximal to the distal phalanx (Grade 3 or 4 frostbite injury) and demonstrated loss of perfusion at or proximal to the middle phalanx immediately after rewarming.

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

The Wilderness Medical Society convened an expert panel to develop a set of evidence-based guidelines for prevention and treatment of frostbite. We present a review of pertinent pathophysiology. We then discuss primary and secondary prevention measures and therapeutic management. Recommendations are made regarding each treatment and its role in management. These recommendations are graded on the basis of the quality of supporting evidence and balance between the benefits and risks or burdens for each modality according to methodology stipulated by the American College of Chest Physicians. This is an updated version of the guidelines published in 2014.

Thrombolytic Salvage of Threatened Frostbitten Extremities and Digits: A Systematic Review

Frostbite is a cold injury that results in soft tissue loss and can lead to amputation. Vascular thrombosis following injury causes ischemic tissue damage. Despite understanding the pathology, its treatment has remained largely unchanged for over 30 years. Threatened extremities may be salvaged with thrombolytics to restore perfusion. The authors performed a systematic review to determine whether thrombolytic therapy is effective and to identify patients who may benefit from this treatment. The Pubmed, EBSCO, and Google Scholar databases were queried using the key words “thrombolytics,” “frostbite,” “fibrinolytics,” and “tPA.” Studies written after 1990 in English met inclusion criteria. Exclusion criteria were failure to delineate anatomic parts injured, failure to report number of limbs salvaged, animal studies, and non-English language publications. Thrombolytic therapy was defined as administration of tPA, alteplase, urokinase, or streptokinase. Forty-two studies were identified and 17 included. Included were 1 randomized trial, 10 retrospective studies, 2 case series, and 4 case reports. One thousand eight hundred and forty-four limbs and digits in 325 patients were studied and 216 patients treated with thrombolytics and 346 amputations performed. The most common means of thrombolysis was intra-arterial tPA. The most common duration of therapy was 48 hours. Limb salvage rates ranged from 0% to 100% with a weighted average of 78.7%. Thrombolytics are a safe and effective treatment of severe frostbite. They represent the first significant advancement in frostbite treatment by preventing otherwise inevitable amputations warranting both greater utilization and further research to clarify the ideal thrombolytic protocol.

The Use of tPA in the Treatment of Frostbite: A Systematic Review

BACKGROUND

The use of tissue plasminogen activator (tPA) for the treatment of frostbite has been reported and advocated, but its efficacy has not been well established. We conducted a systematic review to guide physicians on the role of tPA in the treatment of frostbite. Our hypothesis was that the use of tPA improves clinical outcomes, as measured by amputation rate.

METHODS

We searched MEDLINE (PubMed) and EMBASE for primary research articles on the use of tPA for the treatment of extremity frostbite. Information related to study design, outcomes, and complications was extracted. A total of 204 citations were screened, and then 35 abstracts and 24 reports were reviewed. Fifteen studies met the standard for final review.

RESULTS

One randomized, prospective study; 3 cohort studies; 8 case series; and 3 case reports were found. A total of 208 patients were treated. Differences in protocols, inclusion criteria, and outcomes measures prevented combining the study results. In all the studies, the authors reported that the use of tPA was or may have been useful in reducing amputation rates or increasing tissue salvage. Complication rates ranged from 0% to 100%, with a combined rate of 13%. The quality of the evidence was low.

CONCLUSIONS

Due to the low scientific quality of the studies, the efficacy of tPA in reducing amputation rates cannot currently be established. Randomized, prospective trials or well-controlled cohort studies are needed to better assess the role of tPA. Consideration should be given to limiting its use to research protocols.

[Physical and chemical emergencies in dermatology]

Physical and chemical emergencies are often caused by household or work accidents. Regardless of the medical field and outside specialized clinics, the physician may be confronted with the situation for first or secondary care. The identification of the causing agent and a rapid assessment of the extent and severity of the tissue damage are essential to initiate early transfer to a specialized burn clinic. Grade 2b tissue damage is usually surgically treated. Smaller and superficial injuries can often be conservatively treated. Even supposedly safe and over-the-counter medicines can also lead to serious tissue damage.