PP1123 - Ototoxic Drug Exposure and Hearing Loss in Neonates: A Scoping Review

Abstract: The current study's scoping review of 28 articles that matched the inclusion criteria aims to map the effects of ototoxic medications on neonates hearing. The dosage levels/ intervals, exposure time, serum concentration levels, and hearing outcomes were extracted from the articles and charted. Studies on the effects of amikacin exposure revealed a stronger correlation between ototoxicity and aberrant trough concentrations. There was no hearing loss reported despite elevated trough levels of gentamicin exposure. Hearing loss was observed to have a dose-dependent risk after exposure to vancomycin. Monitoring and maintaining the serum concentration is necessary to prevent negative effects on hearing.
 

 

Summary: Rationale: Aminoglycosides and loop diuretics are the most often used ototoxic medications for critically unwell neonates in NICUs. It can be difficult to obtain information on the drugs, dosage levels/interval, duration of exposure, and peak and trough concentration levels in neonates from medical records. As a result, audiologists and screening professionals frequently underreport this risk factor. This could be due to the lack of clarity and consistency on the guidelines or protocol reported on this risk factor.


Aim: The scoping review aims to investigate the impact that ototoxic medications have been documented to have an effect on neonates hearing and to study the relationship between peak and trough concentration level and occurrence of hearing loss.



Objectives:

• To map the effects of aminoglycosides and loop diuretics drugs, their dosage level and dosage interval on neonates hearing.

• To evaluate the effect of peak and trough concentration levels of ototoxic drugs on newborns hearing.



Design: A scoping review was conducted to identify the studies on ototoxic drug exposure among neonates. From January 2010 until 2022, articles that addressed neonatal hearing status and ototoxic drug exposure were deemed appropriate for inclusion. Also, articles that clearly delineates on the exposed dosage levels, duration of exposure, and effect of peak and serum trough concentration levels were included in the study.



Results: Twenty-eight studies met the inclusion criteria for the scoping review. Based on the drug used in the study population, the studies were separated into groups that included Gentamicin, Amikacin, Vancomycin, Loop diuretics, and a combination of drugs. Dosing levels/ interval, duration of exposure serum concentration levels and hearing outcomes were data extracted from the studies and charted. For Gentamicin, Amikacin and Vancomycin, majority of the studies used the Neo fax guidelines of 4 to 5mg/kg; 15 to 18 mg/kg; 10 to 15 mg/kg respectively, with dosage intervals ranging from 24 to 48 hours.

According to the reviews, increased trough concentrations, dosage levels/ interval and dosage duration were the indicators of the toxicity thresholds for hearing loss. Four out of five included studies demonstrated a stronger correlation between Amikacin exposure and ototoxicity and aberrant trough concentrations. Six out of seven studies on Gentamicin exposure indicated higher trough concentration levels in few infants, but no reports of hearing loss. Vancomycin exposure (2 out of 4 studies) had a dose-dependent risk of acquiring hearing loss.



Conclusion: Monitoring and maintaining serum concentrations are necessary to prevent adverse effects since drug dosage and interval affects therapeutic concentration levels. The results of the scoping review emphasize the significance of therapeutic drug monitoring. An appropriate dosing and monitoring protocol along with the baseline and follow-up audiological evaluation such as ABR and fine structure OAEs are warranted in NICU neonates.