MATERIALS AND METHODS: A retrospective repeated crosssectional study was conducted by recruiting patients with cochlear implants presenting to the Dr. Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia between 2017 and 2021. Basal (b1, b2) and apical (a1, a2) electrodes, representing the outermost and innermost parts of the cochlear implant electrodes, were measured at switch on and at 1 year post-implantation.
RESULTS: A total of 123 patients, with a total of 123 cochlear implant samples, were included in the analysis. We found a substantial change in electrical impedance between switch on and follow-up periods, where the impedance levels of basal electrodes decreased (b1: mean difference (MD) -1.13 [95% confidence interval (CI): -1.71, -0.54], p<0.001; b2: MD -0.60 [95%CI: -1.17, -0.03], p=0.041) and those of apical electrodes increased (a1: MD 0.48 [95%CI: -0.28, 0.99], p=0.064; a2: MD 0.67 [95%CI: 0.12, 1.22], p=0.017). We also found that the choice of surgical approaches for implant insertion may affect the electrode impedance. Cochleostomy approach resulted in a higher impedance than round window in basal (b1) and apical (a2) electrodes both at switch on and follow-up (b1 at switch on and at follow-up: p=0.019 and p=0.004; a2 at follow-up: p=0.012). Extended round window approach also resulted in a higher impedance than round window in basal (b1) and apical (a2) electrodes at follow-up (p=0.013 and p=0.003, respectively).
CONCLUSION: Electrical impedance of cochlear implant electrodes may change over time, highlighting the importance of regular impedance assessments for cochlear implant users to ensure optimal device function. The round window approach resulted in better initial and long-term impedance levels compared to cochleostomy, and better long-term impedance levels than extended round window. Extended round window approach also gives better impedance level than cochleostomy. Further research should investigate the potential interplay between surgical approach and other factors that may impact impedance levels to confirm our findings.
Materials and Methods: Data of five strong opioids consumption (morphine, oxycodone, fentanyl, pethidine, and methadone) between 2005 and 2014 from Malaysia, Singapore, Indonesia, Thailand, and Vietnam were extracted from the Pain and Policy Studies Group. Defined daily doses per 1000 inhabitants per day (DDD/1000 inhabitants/day) was used for calculating the annual amount of opioid use.
Results: The total consumption of five strong opioids was increased in all five Southeast Asian countries during a 10-year study period. Malaysia was recorded with the largest increase of the opioid consumption (993.18%), followed by Indonesia (530.34%), Vietnam (170.17%), Singapore (116.16%), and Thailand (104.66%). Malaysia also had the highest total strong opioid consumption (11.2 DDD/1000 inhabitants/day), primarily for methadone. Among the opioids used for pain management, fentanyl was primarily used in Malaysia and Singapore but the greatest increase in these two countries was for oxycodone. Fentanyl was also primarily used in Indonesia while morphine was predominantly used in Thailand and Vietnam.
Conclusion: Growing trends of strong opioids consumption in all five Southeast Asian countries demonstrated in this study may indicate improved access to opioid analgesics in these countries. Given the increasing trends, it is important to ensure that the utilization of opioids is according to the guideline to prevent the negative consequences of opioids particularly when used in chronic non-cancer pain.