Cold Injury.

Cold injury has been documented for centuries and remains a concern for military personnel, winter recreationalists, and urban homeless populations. Treatment advances in the last decades have included thrombolytic and prostaglandin therapies however the mainstay remains early recognition and rapid rewarming. This chapter focuses on frostbite, with a brief overview of other cold related conditions.

Oropharyngeal Swelling and Airway Obstruction from Environmental Cold Exposure: A Case Report.

A 19-year-old male presented with facial frostbite and severe oropharyngeal edema after prolonged riding of a snowmobile without any facial covering. The diffuse swelling eventually progressed to airway obstruction, requiring a surgical airway. No alternative explanation was found for his presentation, making this the first case found in the literature of airway obstruction secondary to environmental cold exposure.

The classification of freezing cold injuries - a NATO research task group position paper.

INTRODUCTION: Freezing cold injuries (FCI) are a common risk in extreme cold weather operations. Although the risks have long been recognised, injury occurrences tend to be sparse and geographically distributed, with relatively few cases to study in a systematic way. The first challenge to improve FCI medical management is to develop a common nomenclature for FCI classification. This is critical for the development of meaningful epidemiological reports on the magnitude and severity of FCI, for the standardisation of patient inclusion criteria for treatment studies, and for the development of clinical diagnosis and treatment algorithms. METHODOLOGY: A scoping review of the literature using PubMed and cross-checked with Google Scholar, using search terms related to freezing cold injury and frostbite, highlighted a paucity of published clinical papers and little agreement on classification schemes. RESULTS: A total of 74 papers were identified, and 28 were included in the review. Published reports and studies can be generally grouped into four different classification schemes that are based on (1) injury morphology; (2) signs and symptoms; (3) pathophysiology; and (4) clinical outcome. The nomenclature in the different classification systems is not coherent and the discrete classification limits are not evidence based. CONCLUSIONS: All the classification systems are necessary and relevant to FCI medical management for sustainment of soldier health and performance in cold weather operations and winter warfare. Future FCI reports should clearly characterise the nature of the FCI into existing classification schemes for surveillance (morphology, symptoms, and appearance), identifying risk-factors, clinical guidelines, and agreed inclusion/exclusion criteria for a future treatment trial.

Convolutional neural network models for automatic diagnosis and graduation in skin frostbite.

The study aimed to develop and validate a convolutional neural network (CNN)-based deep learning method for automatic diagnosis and graduation of skin frostbite. A dataset of 71 annotated images was used for the training, the validation, and the testing based on ResNet-50 model. The performances were evaluated with the test set. The diagnosis and graduation performance of our approach was compared with two residents from burns department. The approach correctly identified all the frostbite of IV (18/18, 100%), but with respectively 1 mistake in the diagnosis of degree I (29/30, 96.67%), II (28/29, 96.55%) and III (37/38, 97.37%). The accuracy of the approach on the whole test set was 97.39% (112/115). The accuracy of the two residents were respectively 77.39% and 73.04%. Weighted Kappa of 0.583 indicates good reliability between the two residents (P = .445). Kendall's coefficient of concordance is 0.326 (P = .548), indicating differences in accuracy between the approach and the two residents. Our approach based on CNNs demonstrated an encouraging performance for the automatic diagnosis and graduation of skin frostbite, with higher accuracy and efficiency.

Frostbite of The Extremities - Recognition, Evaluation and Treatment.

OBJECTIVES: Frostbite refers to the freezing of body tissue which is caused by prolonged exposure to cold temperatures and results in tissue destruction. Tissue damage is due to both immediate cold-induced cell death and the more gradual development of localized inflammatory processes and tissue ischemia. A detailed treatment plan based on the current UpToDate literature is needed to decrease morbidity and mortality rates. METHODS: The United States National Library of Medicine (PubMed/Medline), EMBASE, Web of Science, and the Cochrane Database of Systematic Reviews were systematically searched to identify publications relevant to this review. CONCLUSION: In this review, we present the current knowledge on the diagnosis and treatment of frostbite injuries. We then provide an extended and detailed treatment plan, from first aid in the field to treatment of short and long-term complications .

Pediatric Environmental Cold Injuries.

Cold weather injuries are relevant concerns for children during winter sports and outdoor activities. To mitigate the risk of cold injury in this high-risk population, providers can educate parents on proper outdoor attire as well as the added risks of wind and water exposure. There are 2 types of environmental cold injuries: freezing injuries and nonfreezing injuries. Frostbite is a freezing injury from direct contact with cold air or surfaces. The extent of injury depends on the depth to which the freezing extends. Treatment involves rewarming the frozen tissue with warm water baths and considering analgesia. Hypothermia is a nonfreezing cold injury, and it can occur even when ambient temperatures are above freezing. When there is a decrease in the body's core temperature, hypothermia progresses from mild to severe symptoms. Treatment of hypothermia is threefold but is also dependent on the core body temperature, as colder core temperatures will require more aggressive warming techniques. Hypothermia treatment involves passive protection from further heat loss (ie, removing wet clothing), which helps the body to warm itself. Treatment also involves active external rewarming wherein a heat source, such as a heated blanket, is used to increase body temperature. Active internal rewarming is the delivery of heat inside the patient's body, such as warmed intravenous fluids.

Frostbite of the upper extremities: Hot issues in diagnosis and surgical treatment (review).

BACKGROUND: Frostbite is a severe thermal injury, which characterized by tissue necrosis with a high percentage of amputations, disability of patients. METHODS: According to the databases Web of Science, Google Scholar, PubMed, E-library down to 2001-2021 the search for works related to the problem of diagnosis, treatment of frostbite of the upper extremities was made. Actual possibilities of diagnostics, the questions of classification, treatment of frostbite, including the features of plastic surgery operations used to close hand defects after excision of necrotic tissues have been analyzed. RESULTS: Frostbite is more common in people with alcohol dependence, mental illness and in socially disadvantaged groups. The most informative instrumental methods of diagnosis: bone scintigraphy, magnetic resonance imaging, single-photon emission computed tomography. Thrombolytic therapy (tPA) and prostacyclin are most effective if used within the first day after tissue rewarming. With deep frostbite and late medical care surgical treatment is fundamental. Amputation and debridement are carried out after the formation of the demarcation line. To replace soft tissue defects that extend beyond the fingers, it is preferable to use fasciocutaneous flaps. CONCLUSION: The defining moments in the treatment of deep frostbite are timely diagnosis and complex treatment. With late admission surgical treatment, including reconstructive skin plastic surgery, becomes important.

[Corrosions and frostbites].

Thermal burns are by far the most frequent and account for approx. 90% of all burns, while frostbites, chemical and electrical burns (CB) cover the remaining approx. 10%. This review gives an overview of the treatment of corrosions and frostbites. CB and frostbites are relatively rare and prompt initiation of proper treatment is essential for both. CB should be diluted as soon as possible, preferably with a neutralizing solution. Treatment of systemic hypothermia comes before management of peripheral frostbite. Frostbites involve thawing in warm water, followed by vasodilation, thrombolysis and amputation if indicated.

Management and Outcome of Feet Deep Frostbite Injury (III and IV Degrees): A Series Report of 36 Cases.

Deep feet frostbite is a severe trauma and often leads to amputation due to full-thickness skin necrosis and subcutaneous tissue damage. A retrospective analysis was performed between June 2013 and June 2019 to review the management measures and outcomes of clinical treatment, and available data had been collected including demographic characteristics, risk factors, and injury environment record. Treatment protocols, wound management, and outcomes were also presented. There were 36 patients diagnosed with deep feet frostbite with a mean age of 51.5 years; the ratio for male to female is 5:1. Drunk and mental disorders were the main risk behaviors for frostbite occurrence. As for the injury environment, mean temperature and wind speed were -20.5 °C and 3.3 m/s, respectively. Fourteen cases achieved wound healing without surgery intervention, 5 cases received skin graft, and 17 cases received amputation. Most amputations (12 cases) were restricted at toe level; only 1 case received whole feet amputation. Our finding indicated that feet deep frostbite in our hospital showed a male predominant and older age including various risk behaviors and coexistence risk factors. Clinical management based on pathology mechanism needs further improvement, as the amputation rate was still high. How to avoid amputation and lower the amputation level are the focus of future efforts.

Cutaneous Cold Weather Injuries in the US Military.

Service members of the US Military are at risk for cutaneous cold weather injuries due to the demands of military training, combat operations, and peacekeeping missions. In this article, we review common cutaneous cold weather injuries likely to be encountered in the military, including frostbite, immersion foot, pernio, Raynaud phenomenon (RP), and cold urticaria. We aim to bring awareness to these specific injuries to improve diagnostic and treatment outcomes, both in service members and civilians.

Social Determinants of Poor Outcomes Following Frostbite Injury: A Study of the National Inpatient Sample.

Severe frostbite injury can result in significant disability from amputation of limbs and digits which may be mitigated through prompt medical care. The reported rates of amputation vary widely between centers. Our aim was to describe the incidence and factors associated with amputation secondary to frostbite injury in the United States using a national sample of hospitalizations. Admissions for frostbite injury were identified in the National Inpatient Sample (2016-2018). Factors associated with amputation were assessed by multivariable logistic regression and clustered by hospital. The overall incidence of frostbite injury in the United States is 0.83 of 100,000 people. Of the social factors associated with frostbite injury, homelessness and the black race were independently associated with a higher likelihood of amputation at the primary admission. Diagnosis of cellulitis was a predictor of amputation. Homeless frostbite patients were more frequently discharged against medical advice and were less likely to discharge with supportive medical care, despite having a higher rate of more severe injury. Disability from amputation following frostbite injury affects at least 20% of frostbite-injured patients and disproportionally affects the homeless population. Further study is needed to ascertain the decision making that leads to early amputation following frostbite injury, especially in the homeless and black population. Outreach and education efforts should be initiated to promote salvage of functional limb length following frostbite injury.

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.