Early rewarming effect of athermal insulation device equipped with self-heating individual meal packs on severely burned domestic rabbits under extremely cold conditions

Zhang Yongsheng; Zhang Linyi; Tuxunayi Hasimu; Zhang Xiaoyun; Liu Bo; Yuan Long

doi:10.3969/j.issn.1009-4237.2025.10.003

Abstract：Objective To investigate the effect of a portable thermal insulation device,equipped with self-heating individual meal packs as the heating source,on the rewarming of severely burned domestic rabbits in the ear-ly stage under extremely cold conditions.Methods Altogether 18 healthy domestic adult rabbits weighing(3.50±0.20)kg were numbered randomly as 1-18 and then divided into two groups,namely group A(odd numbers,the study group)and group B(even numbers,the control group).Each group contained 9 rabbits.Then,the animal model of 30%total body surface area(TBSA)with 3rd-degree skin burns was performed.For each group,the ani-mals were placed in a 2.5 kg military sleeping bag separately after modeling,and then each of the bag were put into an ultra-low temperature freezer set at-30 ℃.Meanwhile,each rabbit was supplied with oxygen and treated with the same anti-shock rehydration.For group A,the sleeping bag was equipped with two 20-patten self-heating individual meal packs as the heat source,which were replaced every 15 min.The pulse indicator continuous cardiac output technology was adopted to monitor the changes in body temperature and cardiac output at 2,4,6 and 8 h after injury.Results At 2,4,6,and 8 h post-injury,the mean body temperatures(℃)of rabbits in both groups were decreasing continuously,but the decreasing trend was milder in group A,and comparison between the two groups revealed signif-icant differences at all time points(38.97±0.60 vs.38.08±0.35,38.56±0.42 vs.36.60±0.21,38.31±0.33 vs.35.07±0.37,38.23±0.39 vs.33.41±0.47,all P<0.05).At4,6,and8 h post-injury,the mean cardiac output(L/min)in both groups decreased too,but significantly milder in group A(0.84±0.05 vs.0.71±0.06,0.75±0.04 vs.0.52±0.03,0.72±0.02 vs.0.43±0.03,all P<0.01).Conclusion Under extremely low tem-perature,rabbits with severe burns,though with warming interventions,show decreased body temperature and cardiac output,but the insulation devices utilizing self-heating individual meal packs as a heat source can significantly miti-gate the decreasing trend at an early stage after severe burns,effectively maintaining the core temperature,and markedly reducing the impact of anextremelylow-temperature environment.