Experimental Observation On The Ototoxicity Of Povidone-iodine To Guinea Pigs

Objective:To investigate the degree of damage to the middle ear mucosa and inner ear toxicity of povidone-iodine solution.Methods:Twenty-six guinea pigs with normal weight and hearing were randomly divided into 4 groups,the control group 1(one-time normal saline administration)4;the control group 2(continuous normal saline administration)4;the experimental group 1(one-time povidone-iodine administration)9 rats;experimental group 2(continuous povidone-iodine administration)9 rats;the one-time administration group was injected with normal saline or 5% povidone iodine 0.2ml into both ears through the tympanic cavity,and the liquid was sucked out after 10 minutes;Continuous administration group: injection of normal saline or 5% povidone iodine 0.2ml through both ears through the tympanic cavity,and aspirate the medicinal solution once a day after acting for 10 minutes.After 7 days,all guinea pigs underwent ABR test;after the test,the auditory vesicles were quickly taken out,and the middle ear cavity was scored by the scoring system;then,take out the cochlear basilar membrane,and the internal and external hair cells were observed by immunofluorescence staining.Results:1.Before the experiment,the hearing of guinea pigs in all groups was normal;2.After the experiment,one ear of the saline administration group had a slight hearing loss,but not more than 10 d B n HL,the difference was not statistically significant(p>0.05).There was no mucosal thickening,hematoma,hyperemia,or adhesion in the middle ear in the one-time normal saline administration group.There was no loss of cochlear basilar membrane hair cells in the result of immunofluorescence staining;3.There was a slight hearing loss in 1 ear in the continuous saline administration group,but no more than 10 d B n HL,the difference was not statistically significant(p>0.05).In the continuous saline administration group,there was occasional mucosal thickening and hyperemia without hematoma and adhesions are formed,and there is no loss of cochlear basilar membrane hair cells in immunofluorescence staining;4.In the one-time povidone-iodine administration group,2 ears had no hearing loss,and the remaining 16 ears had 10-65 d B n HL hearing loss.The difference was statistically significant(p<0.05).The one-time povidone-iodine administration group had mucosal congestion And hematoma are the main changes,there is no mucosal thickening and adhesion phenomenon,but the immunofluorescence staining result shows no loss of basement membrane hair cells;5.In the continuous povidone-iodine administration group,14 ears were totally deaf,90 d B n HL failed to elicit the III wave,and the remaining 4 ears also had serious hearing loss,the difference was statistically significant(p<0.05),and all middle ears had obvious mucosal thickening,Hematoma,congestion,adhesions,and the hair cells in each circle of the cochlear basilar membrane are lost to varying degrees.Conclusion:5% povidone-iodine solution can damage the middle ear mucosa and is ototoxic.We should avoid povidone-iodine solution entering the middle ear cavity during ear surgery.