Evidence-based injury prediction data for the water temperature and duration of exposure for clinically relevant deep dermal scald injuries

Deep dermal burn injuries require extensive medical care; however, the water temperatures and durations of exposure that result in a severe scald injury are unknown. This study used a porcine burn model to investigate the time and temperature threshold for clinically relevant deep dermal injuries for both immersion (long duration) and spill/splash (short duration) scald events. Scald wounds were created on the flanks of anaesthetized juvenile large White pigs (27kg). Acute tissue injury evaluations performed at 1hour and days 1, 3, and 7 postburn (16 pigs) included: wound examination, biopsies, and laser Doppler imaging. Up to 20 burn combinations were tested including: 50-60 degrees C water for 1-10 minutes (immersion); and 60-90 degrees C water for 5seconds (spill/splash). Burn conditions demonstrating mid-to-deep dermal damage histologically were followed for 21days to assess time to reepithelialize (eight pigs). Histologically, depth of damage increased until day 3 postburn. Damage to 75% of the depth of dermis was associated with burns taking longer than 3weeks to fully reepithelialize. For spill/splash (5seconds) scalds, water at 75 degrees C showed damage to mid-dermis or deeper by day 3; however, only burns from water 85 degrees C were not reepithelialized by day 21. For immersion scalds of equivalent duration, water at 55 degrees C caused significantly deeper dermal damage than 50 degrees C (p<0.05) at day 3. Immersion scalds that were not fully reepithelialized by day 21 included 50 degrees C for >10minutes, 55 degrees C for 5minutes, 60 degrees C for 60seconds, and 70 degrees C for>15 seconds. This research provides valuable evidence-based injury prediction data, which can be used to inform future burn injury prevention guidelines/legislation to reduce the risk of severe scald injuries and support medicolegal opinions for cases where an inflicted mechanism of injury is alleged.