From: Systematic review of ototoxic pre-surgical antiseptic preparations – what is the evidence?
Author, Year | Population | Intervention | Control | Outcome |
---|---|---|---|---|
J Aursnes, 1982 [5] | 28 Guinea Pigs. Baseline Preyer’s reflex measured in all study animals. | Solutions tested: a) Iodine in 70% alcohol b) Iodophor in 70% alcohol c) Iodine in aqua dest. d) Iodophor in aqua dest. Exposure time 10, 30 or 60 minuets. Histopathology assessed after 2 weeks | Contralateral ear to experimental ear | a) Gross examination of the ear showed no mucosal changes after 10 mins of exposure for Iodine or Iodopher in aqua dest. b) Middle ear mucosal damage worst for solutions in 70% alcohol. c) Cochlear damage with exposure time of 60 min with Iodophor in 70% alcohol. d) Vestibular damage seen with Iodophor in 70% with exposure times of 30-60min |
T Morizono, 1982 [7] | 30 Chinchilla | Solutions tested: a) Povidone-iodine Solution at 1:10 dilution (1.0% available iodine) b) Povidone-iodine Scrub* at 1:10 dilution (0.75% available iodine) c) Povidone-iodine Scrub at 1:100 dilution Exposure time 10mins Effect on Compound Action potential (CAP) tested 2 hours, 24 hours post exposure *Scrub contains detergent | Contralateral ear to experimental ear | a) Povidone-iodine Scrub more toxic to cochlear function then solution b) Evoked action potential measure at round window, no change 2 hours after exposure with 1:10 dilution of Iodine Solution c) Evoked action potential measure at round window 2 hours after exposure with 1:10 dilution of Iodine Scrub caused severe depression at all tested frequencies (2, 4, 8, 12kHz) d) Increased toxicity with increased concentrations for both solution and scrub |
T Morizono, 1983 [8] | 30 Chinchilla | Solutions at different dilutions d) Povidone-iodine Solution at 1:10 dilution (1.0% available iodine) e) Povidone-iodine Scrub* at 1:10 dilution (0.75% available iodine) f) Povidone-iodine Scrub at 1:100 dilution Duration of exposure time 10mins Effect on Compound Action potential (CAP) tested 2 hours, 24 hours post exposure *Scrub contains detergent | Contralateral ear to experimental ear | a) High frequency losses (8 and 12kHz) after 10, 30 and 120min exposure to iodine scrub at 1:100 dilution |
T. Inchibangase, 2011 [6] | 70 Guinea Pigs – Divided into groups based on age (infant, young and adult) | Solution tested a) Povidone-iodine 10% solution b) Povidone-iodine scrub Effect on Compound Action potential (CAP) tested at 24h, 7days and 28days | Contralateral ear to experimental ear | a) No action potential at 24hours after application of Povidoneiodine scrub b) 24 hours after exposure to povidone-iodine solution, significant ototoxicity measured in infant group, less in young and least in adult c) 8 fold dilution of povidoneiodine solution showed no hearing loss in adults, loss for young at 2 and 4kHz d) Showed aged related variation associated with ototoxicity in guinea pigs |
M. Ozkiris [16] | 24 Sprague-Dawley Rats | Solution tested a) 5, 7.5, 10% Povidone-iodine solutions No exposure time given. Otoacoustic emissions measured at 1 and 10 days after exposure | Contralateral ear to experimental ear | a) At 5% concentration some statistically significant decreased hearing at day 1 but resolved by day 10 b) At 7.5% and 10%, day 10 results showed decreased in hearing in frequencies ranging from 1.5-12kHz |
R. Yagiz, 2003 [17] | 7 adult guinea pigs | Solution Tested a) Povidone-iodine 10% solution No exposure time given. Hearing tested at 10 days and 4 weeks after exposure | a) Saline as a negative control in the contralateral ear to experimental ear in 4 animals b) Gentamycin as a positive control the contralateral ear of 3 experimental animals | a) 4 animals could not be tested due to severe oedema of the external auditory canal b) No Otoacustic emissions present 10days or 4 weeks after exposure |