An Experimental Investigation On Water-Soluble Chitosan Membrane Treating Pressure Ulcers Deduced By Ischemia-Reperfusion Injury

ObjectiveTo investigate the effect of water-soluble chitosan membrane(WSCM) on pressureulcers (PU) deduced by ischemia-reperfusion injury(IRI).WSCM was prepared accordingto its quliaty standard，and PU models were established to treated by WSCM withrecombinant human Epidermal Growth Factor(rhEGF) as control.Meanwhile,the effect ofWSCM on PU patients was well.Method1、Salivation method was employed to prepare WSCM with the WSC concentration of6%,the temperature of55℃for baking.2、To establish PU models,SD rats were used to be treated by contiously pressed in theskin for2hours three times a day within5days.3、(1)20SD rats were underwent IRI-1d, IRI-2d, IRI-3d,IRI-4d,IRI-5d experiments,then the injury was estimated acooding to the PU grades standard, and SOD/MDA in bloodsamples were determined.(2) The effects of WSCM(n=10) and rhEGF(n=10) on SD PUrats were observed by comparing with the effects of untreated group (n=10) as control.SOD and MDA levels in blood as therapeutic index were determined as well.(3)30patients with II-III grade PU were divided into two groups randomly: WSCM group (n=15)and rhEGF group (n=15), all the patients were treated with WSCM or rhEGF, respectively.Wound area and the wound healing time were employed as assessment indicators.Results1、The optimal concentration of WSCwas6%, the best baking temperature was55℃and the best baking time was6h. The WSCM was in conformity with the quality standards. 2、(1)20SD rats with different IRI cycles were got blood in1std,2ndd,3rdd,4thd,5thdfrom femoral arterial respectively, the results of blood biochemical index showed that:SOD decreased and MDA increased in the IRI-1d SD rats; SOD increased and MDAdecreased in the IRI-2d SD rats; SOD continued to decline and MDA increased graduallyafter IRI-3d.(2) The value of SOD was significantly lower and the value of MDA wassignificantly higher in the SD rats of pressure ulcers, it was also to say when the IRI-5dfinished; the values of SOD and MDA were significant differences from the pre-test data(P＜0.05), the differences were statistically significant.(3) The pressure ulcers of SD rats inuntreated group eventually healed due to its own self-healing ability, the average healingtime was22d; the healing process was most obvious in the first seven days of the SD ratsin the group WSCM, and it’s significant differences compared with the other two groups(P＜0.05), the average healing time was19d; the wound healed slowly of the SD rats in thegroup rhEGF, the average healing time was21d, and there were no obvious differencescompared with the SD rats in the group untreated.3、In the30clinical patients with pressure ulcers, the average healing time is(25±1.26)d of the15patients in the group WSCM, and the average healing time is(29±2.07)d of the15patients in the group rhEGF, P＜0.05; compared with the efficacy ofwound healing after they used10days drugs, group WSCM was93.3%and group rhEGFwas20%.Conclusion1、WSCM was made by the method of salivation in forming properties and stabilitywere well.2、Establishment of animal model of PU induced by IRI.3、Verification of the WSCM in PU treatment of the independent action.4、The treatment of PU by WSCM in clinical experiment achieved initialresults.