Study On The Effect Of Hypochlorous Solution On The Biofilm Of Acinetobacter Baumannii And Its Clinical Efficacy On The Wounds Of Acinetobacter Baumannii Infection

Objective 1.To detect the bactericidal effect of hypochlorous solution on AB and to study the antibacterial effect of hypochlorous solution on AB in different states.2.To study the clinical efficacy of hypochlorous solution on the wounds infected by AB.Method 1.The strains with the strongest film-forming ability were screened from the clinical strains of AB sent to The 940th Hospital of Joint Logistics Support force of Chinese People’s Liberation Army,and then the screened strains were used for subsequent experiments to detect the lowest bactericidal concentration(MBC),the shortest bactericidal time and the lowest biofilm clearance concentration(MBEC)of AB by hypochlorite solution,and finally to study the bacterial biofilm formation pattern of AB.Finally,the biofilm formation pattern of AB was studied,and the biofilm removal effect of hypochlorite solution on AB was explored.2.A total of 42 patients with AB traumatic infection who met the experimental criteria were admitted from January 2021 to January 2023 from the Department of Burns and Plastic Surgery of Lanzhou University Second Hospital,and the patients were randomly divided into experimental and control groups according to the order of admission using the random number table method.The experimental group was given hypochlorite gauze wet dressing change and the control group was given FCS.NO1 gauze wet dressing change,and both groups were changed once a day.The wound tissue was collected for bacterial culture and quantitative analysis before treatment and after the 10th day after treatment,respectively.Wound bed score(WBS)criteria were used to score the wound bed before treatment and at day 3,7 and 10 after treatment.Finally,the data obtained were subjected to relevant statistical analysis.Results 1.The minimum inhibitory concentration(MBC)of hypochlorite solution for AB was 6.25ug/m L;the bactericidal time of hypochlorite solution at MBC(6.25 ug/m L)for free AB in vitro was 2 min,and the time for AB to form mature biofilm in vitro was 72h;the minimum clearance concentration(MBEC)of hypochlorite solution for AB in mature biofilm state was 12.50ug/ml.The shortest time to dissociate the biofilm of AB by hypochlorite solution with MBEC was 5 min.Within 5-10 min,hypochlorite solution could enhance the removal of bacterial biofilm with the increase of action time.2.The general data of the two groups were not significantly different and comparable.The number of traumatic bacteria in the two groups before treatment was(3.39±1.53)×10~6CFU/g in the hypochlorite group and(3.82±0.94)×10~6CFU/g in the FCS.NO1 group,and there was no significant difference in the number of traumatic bacteria before treatment(P>0.05).After 10 days of treatment,the bacterial count of traumatic tissue in the hypochlorite group was(4.36±0.29)×10~4CFU/g,and that in the FCS.NO1 group was(4.38±0.23)×10~4CFU/g.The bacterial count of traumatic tissue in the hypochlorite group was not significantly reduced compared with that in the FCS.NO1,and the difference was not statistically significant(P>0.05).The wound bed score of hypochlorite group before treatment was(2.64±0.56),while that of FCS.NO1 was(2.58±0.77),and the difference between the wound bed scores of the two groups before treatment was small(P>0.05).After 3 days of treatment,there was no significant increase in the wound bed score between the two groups,and statistical analysis was not significant(P>0.05).After7 days of treatment,the trabecular bed score increased in the hypochlorite group(4.12±0.69a),but it was not significant;the trabecular bed score increased in the FCS.NO1 group(3.61±0.52a),and the statistical analysis was significant(P<0.05).FCS.NO1 group(6.01±0.38a),which was statistically significant(P<0.05).Conclusion 1.Hypochlorous solution has good bactericidal effect on both free AB and biofilm AB.The hypochlorous solution had a rapid killing effect on AB in a stable biofilm state at a low concentration(12.50ug/m L),and the bactericidal effect of hypochlorous solution increased with the increase of the concentration.2.Compared with the wet dressing of hypochlorous solution gauze and FCS.NO1 gauze,both of them could reduce the number of bacteria on the infected wounds of AB,but the hypochlorous solution did not reduce the number of bacteria on the infected wounds of AB.However,hypochlorite solution was not found to be more effective than FCS.NO1 in reducing the number of bacteria on the traumatic surface of AB infection,and the efficacy of hypochlorite solution was significantly better than that of FCS.NO1 in terms of the score of the traumatic bed.