RESUMEN
ABR wave I amplitude represents the synapse of auditory nerve fibers with the inner hair cell and is highly correlated with synapse counts. Cochlear synaptopathy, the loss of synaptic connections between inner hair cells and auditory nerve fibers, has been well-demonstrated in animal models of noise-induced hearing loss. The peak-to-peak wave I amplitude was determined at baseline and 2 weeks after noise exposure. We determined the ABR wave I amplitude at 80 dB SPL at the frequencies of 8, 12, 16, 24, and 32 kHz. A total of 69 strains (1-8 mice/strain) were analyzed. A statistically significant post-noise reduction in wave I amplitude was observed in all the tested frequencies (p < 0.00001). We identify distinct patterns of noise susceptibility and make this complete phenotypic dataset available for general use. This data establishes a new resource for the study of NIHL in mice and we hope this database will be a useful tool to expand the research in this field.
Asunto(s)
Potenciales Evocados Auditivos del Tronco Encefálico , Pérdida Auditiva Provocada por Ruido , Animales , Umbral Auditivo/fisiología , Cóclea , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Pérdida Auditiva Provocada por Ruido/genética , Ratones , Ruido/efectos adversosRESUMEN
PURPOSE: Nausea and vomiting occur in up to 70% of children after adenotonsillectomy, ingested blood during procedure being one of the reasons for emesis. Hypopharyngeal packing (HP) is a common practice among otolaryngologists to prevent blood from being swallowed, but studies in nasal surgeries in adults failed to show efficacy of this technique in reducing postoperative nausea and vomiting (PONV). There are no studies evaluating the effect of HP in adenotonsillectomy in children. The aim of this study is to evaluate the efficacy HP during adenotonsillectomy in children in the prevention of PONV. METHODS: This is a randomized, double-blinded, controlled trial. Children aged 4-16 years, scheduled for adenotonsillectomy due to sleep-disordered breathing were enrolled in Hospital da Criança Santo Antônio (Brazil). 192 participants were screened, while 129 were enrolled and completed follow-up for primary outcome. Patients were randomized in a consecutive manner to receive HP or not during adenotonsillectomy. PONV occurrence was assessed in the first 24 h after surgery in HP and control group and relative risk with 95% confidence interval was calculated. RESULTS: There were 129 patients randomized, 64 in the HP and 65 in the control group. Female were 40.3% and mean ± SD age was 7.3 ± 2.9. Baseline characteristics and surgery variables were distributed similarly between the groups. Incidence of PONV was 20.3% in the HP and 23.1% in the control group. The relative risk for PONV was 0.88 (95% CI 0.46-1.70). CONCLUSION: Our results suggest that there is no benefit of HP during adenotonsillectomy in children for the prevention of PONV. TRIAL REGISTRATION: Brazilian Register of Randomized Trials (REBEC) identifier: RBR-3zjn27; Universal Trial Number U1111-1197-7461.