Bagheri Fereshte, Sheikhzadeh Mahbubeh, Raisi Ahmadreza, Kamali Mohammad, Faridan Mohammad
Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran; Department of Audiology, School of Rehabilitation Sciences, Babol University of Medical Sciences, Mazandaran, Iran.
Department of Audiology, School of Rehabilitation Sciences, Babol University of Medical Sciences, Mazandaran, Iran.
Med Gas Res. 2020 Jul-Sep;10(3):110-113. doi: 10.4103/2045-9912.296040.
Carbon monoxide (CO) poisoning is one of the most common types of fatal poisonings worldwide. Acute exposure to high levels of CO as well as chronic exposure to low levels of CO and excessive noise can lead to high frequency hearing loss. In this study, twelve guinea pigs were randomly divided into two groups: (1) exposed to noise and (2) exposed to noise plus CO. Auditory brainstem responses (ABRs) were measured prior to the experiment and immediately, 5, 10 and 15 days post exposures. There was a significant difference between the ABR thresholds before and immediately after exposure to noise at frequencies of 4, 8, and 16 kHz and the most threshold shift was observed at 8 kHz. There was also a significant difference between the ABR thresholds before and immediately after exposure to noise and CO at frequencies of 2, 4, 8, and 16 kHz which demonstrated a temporary hearing loss after exposure to noise and CO and the major impact of CO on developing noise induced hearing loss occurred at 8 kHz. No significant difference was observed between the ABR thresholds recorded before conducting the experiments and the ones obtained 5, 10 and 15 days after simultaneous exposure to noise and CO at none of frequencies. Simultaneous exposure to noise and CO contributes to transient hearing loss in guinea pigs with the most evident temporary shift at 8 kHz. The methods were accepted in the Ethics Committee of Iran University of Medical Science (registration No. CTRI/2016/01/017170) on January 18, 2016.
一氧化碳（CO）中毒是全球最常见的致命中毒类型之一。急性高浓度接触CO以及慢性低浓度接触CO和过度噪声均可导致高频听力损失。在本研究中，12只豚鼠被随机分为两组：（1）暴露于噪声组；（2）暴露于噪声加CO组。在实验前以及暴露后即刻、5天、10天和15天测量听觉脑干反应（ABR）。在4、8和16kHz频率下，暴露于噪声前后的ABR阈值存在显著差异，且在8kHz时观察到最大的阈值变化。在2、4、8和16kHz频率下，暴露于噪声和CO前后的ABR阈值也存在显著差异，这表明暴露于噪声和CO后出现了暂时性听力损失，且CO对噪声性听力损失发展的主要影响发生在8kHz。在任何频率下，实验前记录的ABR阈值与同时暴露于噪声和CO后5天、10天和15天获得的阈值之间均未观察到显著差异。同时暴露于噪声和CO会导致豚鼠出现短暂性听力损失，在8kHz时暂时性变化最为明显。该方法于2016年1月18日获得伊朗医科大学伦理委员会批准（注册号CTRI/2016/01/017170）。
