Cold burn injuries in the United Kingdom: retain-->A 5-year cohort study of patients presenting to a regional burn unit.

Aims: To assess the aetiology, management and outcomes of cold burn injuries presenting to a regional burn unit in the United Kingdom.

Methods: Retrospective cohort study of consecutive patients over a 5-year period (2018-2022).

Results: Sixty-two patients (M:F 34:38; median age 23.5 years) were identified. The most common aetiology was aerosol (n = 28, 45.2%). Seven (11.5%) injuries were sustained during a social media or peer 'challenge' and 19 (31.2%) were self-harm, of whom 5 (26.3%) were inpatients on a mental health ward at the time of injury. All 'challenge' and self-harm injuries were caused by aerosol. Patients with 'challenge' injury were younger than those with self-harm (p = .007) and non-intentional injuries (p < .001). A greater proportion of self-harm injuries were in female patients compared with non-intentional injuries (p < .001). Median total body surface area (TBSA) was 0.35% (IQR: 0.3). Most burns were superficial partial thickness (n = 35, 56.5%), followed by deep dermal (n = 18, 29.0%), full-thickness (n = 8, 12.9%), and superficial (n = 1, 1.6%). The upper limb was most frequently affected (n = 35, 56.5%). Aetiology and a non-intentional, 'challenge' or self-harm injury did not affect TBSA (p = 0.776 and p = 0.364) or depth (p = 0.353 and p = 0.381). Five (8.1%) patients underwent autografting. The median time to healing was 17 days (range: 7-45, IQR: 22.75). Follow-up ranged from 1 to 173 weeks.

Conclusions: The incidence of cold burns has increased when compared with previous literature. A disproportionate number of cold burns are self-inflicted using aerosols, either as self-harm or because of social media or peer 'challenges'. Other emerging aetiologies include non-intentional skin contact with nitrous oxide containers during its recreational use.