Objective:
Cooling is considered a panacea in burn injury. However,
burn injuries are characterized by an ischemic zone prone to progression,
a phenomenon that can substantially increase morbidity. Cold-induced
vasoconstriction potentially aggravates ischemia and promotes progression.
Therefore we compared the effect of warm (37°C) and cold (17°C) water on
burn progression.
Methods:
The comb burn model creates 4 rectangular burned surfaces
separated by 3 unburned interspaces that become necrotic if untreated. After
heating in boiling water the template was applied for 60 seconds on 24 Wistar
rats randomized into 3 groups: no treatment (CON); treatment for 20 minutes
with cold water (17°C: CW) or warm water (37°C: WW). Burn progression in
surface (planimetry) and Departmenth (histology), as well as microcirculatory
perfusion (laser Doppler flowmetry) were assessed after 1h, as well as 1, 4, and
7 days.
Results:
Both CW and WW delayed burn progression without reducing the
final burn Departmenth (deep dermis). In contrast, only WW but not CW
increased dermal perfusion (81 ± 2% (WW) vs. 62 ± 2% (CW) and 63 ± 1%
(CON), p< 0·05) already 1 hour after burn induction. The difference observed
after one hour led to a complete flow recovery during the observation period
and translated into increased interspace survival, respectively less necrosis with
WW(65 ± 4% vs. 81 + 4% (CW) and 91 ± 2% (CON), p< 0·05) after 7 days.
Conclusions:
Application of warm water significantly improved dermal
perfusion, increased interspace survival, and delayed burn progression.However
it didn't alter the ultimate burn Departmenth of the actually burned area.
Therefore, warm water can create a therapeutic window for targeted nonsurgical
treatment of burn progression.