Ichibangase T, Yamano T, Miyagi M, Nakagawa T, Morizono T
Department of Otolaryngology, Fukuoka University School of Medicine Nanakuma, Jonan-ku, Fukuoka City, Japan.
Int J Pediatr Otorhinolaryngol. 2011 Sep;75(9):1078-81. doi: 10.1016/j.ijporl.2011.05.013. Epub 2011 Jul 7.
Povidone-Iodine preparation is used as a disinfectant in otological surgeries. The ototoxicity of Povidone-Iodine preparation was evaluated using infant, young and adult guinea pigs. The effects of different concentrations and of different exposure durations on compound action potentials were also studied.
MATERIALS & METHODS: Povidone-Iodine was used to fill one middle ear cavity of the guinea pig, and the compound action potential (CAP) was measured from the round window membrane at 24h, 7 days, and 28 days. The contralateral side was filled with saline as control. Test sounds used were clicks and tone bursts of 2, 4, and 8 kHz.
At 24h, Povidone-Iodine solution showed a significant toxic effect in the infant group. In the young animal group, no toxic effect was seen. In the adult group, a mild degree of deafness for 2 kHz was found. At 7 days, the young group showed significant hearing loss for all frequencies, but the adult group did not show any hearing loss. With a half strength solution, both young and adult group did not show hearing loss. At 28 days, with a full strength solution, hearing loss became prominent for all sound stimulation. With 1/8th dilution, the young group showed a moderate hearing loss, but the adult group did not.
The thicker round window membrane in human is expected to provide more protection to the human cochlea than in the guinea pig model that we have studied. Mild hearing loss at 24h and 7 days using 10% solution, but no hearing loss with 5% solution at 7 days may indicate that rinsing of the middle ear cavity with saline during surgery should minimize the ototoxic effect of this product. The age of the animals does influence the outcome of the ototoxicity experiment. From this experiment, Povidone-Iodine preparations in the infant should be used with caution. Povidone scrub should not be used for otologic surgery.
聚维酮碘制剂在耳科手术中用作消毒剂。使用幼龄、青年和成年豚鼠评估聚维酮碘制剂的耳毒性。还研究了不同浓度和不同暴露时间对复合动作电位的影响。
用聚维酮碘填充豚鼠的一侧中耳腔，并在24小时、7天和28天时从圆窗膜测量复合动作电位（CAP）。对侧用生理盐水填充作为对照。使用的测试声音为咔嗒声以及2、4和8kHz的短纯音。
在24小时时，聚维酮碘溶液在幼龄组显示出显著的毒性作用。在青年动物组中，未观察到毒性作用。在成年组中，发现对2kHz有轻度耳聋。在7天时，青年组在所有频率上均出现显著听力损失，但成年组未出现任何听力损失。使用半浓度溶液时，青年组和成年组均未出现听力损失。在28天时，使用全浓度溶液时，所有声音刺激下听力损失都很明显。用1/8稀释液时，青年组出现中度听力损失，但成年组未出现。
预计人类较厚的圆窗膜比我们所研究的豚鼠模型能为人类耳蜗提供更多保护。使用10%溶液在24小时和7天时出现轻度听力损失，但在7天时使用5%溶液未出现听力损失，这可能表明手术期间用生理盐水冲洗中耳腔应可将该产品的耳毒性作用降至最低限度。动物的年龄确实会影响耳毒性实验的结果。从本实验来看，幼龄动物使用聚维酮碘制剂应谨慎。聚维酮擦洗剂不应用于耳科手术。
