Ear, frostbite
In this case, a patient experienced thermal injury (frostbite) as a result of cold exposure while on a ski mountaineering trip in Switzerland. He received treatment at a general hospital in Switzerland. On the day of the cold injury, the patient and his group had climbed 700 meters (2,296 feet) to reach the summit of the Wildstrübel at an elevation of 3245 meters (10,650 feet). After reaching the summit, they began skiing down. The temperature outside was around -18 degrees Celsius (-0.4 degrees Fahrenheit) with strong winds.
Medical history
During the ascent and descent, the 27-year-old’s hoodie did not fully cover his right ear. He experienced some discomfort of his right ear, but did not notice a wound or blister. The next day, he woke up to find a blister had formed on the helix of his right ear. The affected area was not painful, but felt numb to the touch. (Photo 1)
Physical examination
Upon examination, a blister was present on the helix of the patient's right ear. Erythema and edema were also present, affecting the scaphoid fossa and the antihelix. As the blister contained clear fluid, erythema and edema, this can be classified as second-degree frostbite. The area was sensitive to the touch. The total body surface area affected was small, less than 0.1%.
Conservative management
One day after the ascent to the summit, the patient visited the local hospital, but it was no longer necessary as his ear had rewarmed overnight. The attending physician removed the roof of the blister. The patient was instructed to apply silver sulfadiazine cream (SSD) twice daily for one week. There was no need to dress the ear.
Surgery
No surgery was needed in this case.
Outcome
The affected ear was tender for a couple of days. The swelling started to lessen after two days. Four days after the cold exposure, the swelling had almost completely subsided and the wound had healed (Photos 5 and 6).
Two months after the frostbite injury, the ear had healed completely (Photos 7 and 8).
Lessons learned
Prevention is key in cases of frostbite, as with burn injuries. In this case, it is important to take protective measures to prevent further freezing when experiencing discomfort in tissue exposed to cold. Raising awareness among mountaineers and addressing risk factors such as homelessness or pre-existing medical conditions can also help to prevent frostbite.
Due to the delay in presentation in this case, rapid rewarming was not possible. Normally, initial treatment for frostbite should include early rewarming of the affected area using water (37-40°C) that contains an antibacterial agent such as povidone-iodine or chlorhexidine.
In this case, the blister was removed. This decision is often based on the theory that blister fluid containing prostaglandin F2α and thrombohexane B2 could lead to further damage, but the benefit of removing blisters has not yet been proven in trials.
The evidence for therapeutic decision making regarding topical treatment for frostbite is weak. There are multiple options for topical treatment, such as aloe vera ointments, which are advised to be applied every six hours due to aloe vera’s thromboxane inhibiting capacity. In this patient, SSD was applied twice daily to the wound because of its bacteriostatic capacity; this was chosen for the helix, as the main goal was to avoid infection.