| Objective: To explore the detrimental effects of the compound factors of hot and humid environment and trauma on rat's wounds and the whole physiological responses of rats, and the protective function of immediate topical oxygen therapy (TOT) under the influence of the above compound factors, estimate the degree of wounds healing. The study offers theoretical basis to select the therapy of wound nursing in hot and humid environment.Methods: Twenty-four Sprague-Dawley rats, six for each, were divided randomly into four groups: normal environment control group (NEC), normal environment oxygen therapy group (NEO), hot and humid environment control group (HHE), hot and humid environment oxygen therapy group (HHO). After the rat traumamic models were established, the rats of HHE and HHO groups were put into the controlled clinmate room.The rats of HHE and HHO groups were in condition of Tdb(37.53+0.44)C, Twb(32.41+0.60)C, Rh(69.94+2.17)%; and those of NEC and NEO groups were in condition of Tdb(25.35+0.87)C, Twb(19.98+1.11)C, Rh(52.84+2.71)%. The exposure time of each group was 120 minutes.The study was divided into 3 parts: In secton I, (1)Tr, HR, MAP and RF served as observing indexes.During the test, thephysiological indexes were recorded once per 20 minutes; (2)The quantity changes of bacteria in wound tract: the bacteria in the muscle from wound tract at various time were cultivated. In secton II, all rats were sampled to observe the pathological morphology and ultrastructures of rats' muscle of wound under optical microscope and electron microscope at 2h, 4h after trauma. In section III, gross tissue change, wound healing time and the percent of wound healing at 7d after trauma were estimated.Result: (1) Changes of physiological response: Tr, HR, RF between HHE and HHO groups raised straightly. Tr and HR's difference between HHE and HHO is higher than that between NEC and NEO at every time except 0min (P<0.05). RF's difference between HHE and HHO is higher than that between NEC and NEO. There was significant difference on Tr between HHO and HHE every time since 20min after hot exposed (P<0.05). HR and RF in HHO are lower than that in HHE (P<0.05). Trends of MAP of all groups reduced, but MAP is not affected by environment temperature and topical oxygen therapy (P>0.05); (2) Changes of bacteriological quantity: The quantity of bacteria in wound tract in four groups increased with the time prolonged. The quantity of bacteria in two groups in normal environment is lower than that in hot and humid environment (P<0.05). The quantity of bacteria in HHO is smaller than that in HHE at 1h, 2h after injuried (P<0.05); (3) Changes of pathological morphology: In these rats, swollen mitochondria with cristae loss and vacuolization, disorganized myofibrillae with some loss of myofilaments, glycogen granules reduced, macrophages degenerated. The damage of the muscle fibers in HHO is better than that in HHE. The damage of muscle cells in NEC is slighter than that in HHE, the muscle cells in NEO are all normal on the whole; (4) Condition of wound healing: Six wounds were infected on all rats' wound, and general infection rate is 25%. NEC infection rate is 8.33%, NEO is none, and HHE, HHO groups respectively is 12.5%, 4.17%. The wound healing time in HHE is longest, and that in NEO is shortest of four groups.The percent of wound healing at 7d after injuried between NEC and NEO is higher than that in HHE (P<0.01). There is significant difference on the percent of wound healing at 7d after injuried between HHO and HHE (P<0.01).Conclusion: (1) The compounded function of hot and humid environment and trauma is more serious than that of each single factor on rats' acute wound and physiological response; (2) In hot and humid environment, topical oxygen therapy can efficiently decrease rat's Tr, HR and RF, and relatively stabilize MAP, therefore, it can effectively prevent hot injury from processively hurting the trauma wounds and the body; (3) In hot and humid environment, pathological effects induced by hot humid factor... |
PDF Full Text Request