[Morphological changes in the epithelium of the auditory tube with prolonged respiratory support in children of the first year of life]. / Morfologicheskie izmeneniya epiteliya slukhovoi truby pri dlitel'noi respiratornoi podderzhke u detei pervogo goda zhizni.

OBJECTIVE: To analyze the condition of the epithelium of the cartilaginous part of the auditory tube in premature and full-term infants with prolonged respiratory support using noninvasive assisted ventilation (continuous positive airway pressure - CPAP) and artificial lung ventilation (ventilator). MATERIAL AND METHODS: All the obtained material is distributed relative to the gestation period into the main and control groups. The main group (25 children) is represented by premature and full-term live-born children who were on respiratory support for a period of several hours to 2 months, the average gestation period of which was 30 weeks and 40 weeks, respectively. The control group (8 children) is represented by stillborn newborns with an average gestation period of 28 weeks. The study was conducted posthumously. RESULTS: Prolonged use of respiratory support in premature and full-term children, regardless of the type (CPAP or ventilator), leads to a violation of the row of cilia of the ciliated epithelium, various inflammatory processes, as well as to the expansion of the ducts of the mucous glands of the epithelium of the auditory tube, which affects its drainage system. CONCLUSION: Prolonged respiratory support causes destructive changes in the epithelium of the auditory tube, which make it difficult to evacuate the mucous discharge from the tympanic cavity. This negatively affects the ventilation function of the auditory tube and in the future may lead to the development of chronic exudative otitis media.

[Objective parameters of auditory function in premature infants in the first year of life after taking ototoxic antibiotics]. / Ob"ektivnye pokazateli slukhovoi funktsii u nedonoshennykh detei pervogo goda zhizni posle priema ototoksicheskikh antibiotikov.

OBJECTIVE: To compare the condition of auditory function during the first year of life according to the registration of distortion product otoacoustic emission (DPOAE) and short-latency evoked potentials (SLEP) in premature infants who received ototoxic antibiotics to those ones, who did not. MATERIAL AND METHODS: Auditory function was examined in 145 premature infants. Auditory assessment was carried out by registration of DPOAEs, SLEPs and tympanometry. Statistical processing was performed using the program Statgraphics Centurion XV. RESULTS: In this study, according to DPOAE, the average response values of the cochlea in premature infants who had a history of ototoxic therapy, undergo final changes after children reach the age of 6 months. The study of latent periods and threshold values of the V peak of SLEP showed a delay in the maturation process of the perceiving and conducting auditory structures during the first year of life in children who received ototoxic antibiotics in the first month of life. CONCLUSION: We evaluated the timing of the completion of response changes in children of the control group using the DPOAE and SLEP registration data. In children of the study group, we evaluated the effect of the administered ototoxic antibiotics. Timing of audiological control of the hearing organ condition are demonstrated for premature children after ototoxicosis, required methods of its examination are established.

Otoprotective Effect of Cortexin, Cogitum, and Elkar Administered Simultaneously with Netromycin in the Experiment.

We studied possible otoprotective effect of drugs widely used for the correction of perinatal hypoxic brain damage in premature infants. The experiments were carried out on immature rabbits with an immature hearing organ. The auditory function was assessed by DPOAE and ABR methods in intact animals and rabbits treated with therapeutic doses of netromycin alone or in combination with the drugs that normalize metabolic processes in the brain (Cortexin, Cogitum, Elkar, vitamin B2, ATP, and cocarboxylase). It was found that the administered drugs produced an otoprotective effect and reduced the severity, but did not eliminate the ototoxic effect.

[Screening audiological control in children of different ages after taking ototoxic medications]. / Skriningovyi audiologicheskii kontrol' detei raznogo vozrasta posle priema ototoksicheskikh preparatov.

AIM: To compare auditory function during screening of children of different age groups who received ototoxic therapy. PATIENTS AND METHODS: Auditory function was studied in various categories of children receiving ototoxic drugs. Hearing was assessed by the registration of distortion product otoacoustic emission (DPOAE), short-latency evoked potentials (SLEP), tympanometry. Statistical processing was performed using the C program Statgraphics Centurion XV. RESULTS: In this study, screening of auditory function in children suffering from cystic fibrosis and receiving ototoxic treatment revealed pathologic conditions of the middle ear according to tympanometry in 15.4% of cases, impaired auditory function in 28.2% of cases according to DPOAE. Early ototoxicosis presented as a decrease in the amplitude of the response at a frequency of 4 kHz, and a change in the structure of the DP-gram in the form of a shift to the low-frequency area. Examination of the auditory function of premature infants receiving potentially ototoxic drugs in the early neonatal period demonstrated that the administration of ototoxic drugs does not affect the maturation of outer hair cells. CONCLUSION: Audiological control, such as tympanometry and registration of evoked otoacoustic remission should be included in the outpatient observation of children with a history of ototoxic drugs.

[The hearing function in the premature children following their treatment with the use of ototoxic antibiotics]. / Slukhovaia funktsiia nedonoshennykh detei posle lecheniia ototoksicheskimi antibiotikami.

The objective of the present study was the evaluation of the state of the auditory function in the premature children during the first year of life who underwent the neonatal treatment with various ototoxic antibiotics. A total of 232 newborn infants were available for the examination by the methods designed for recording distortion product optoacoustic emission (DPOAE) and short-latency auditory evoked potentials (SAEPs). The 'Statgraphics Centurion XV' program was used for the statistical treatment of the data obtained in the study. The results of recording DPOAE and SAEPs in 232 prematurely born children of different gestational age were used to evaluate their auditory function under conditions of treatment with various ototoxic antibiotics during the early neonatal period. It was shown that such treatment is likely to have an impact on the hearing function of premature children throughout the entire first year of life. Such influence can manifest itself as the enhanced threshold of the appearance of SAEPs peak V and the selective distortion of evoked responses recorded with the help of the DPOAE technique at a frequency of 4.6 kHz. It is concluded that all prematurely born children should be under observation of an otorhinolaryngologist-surdologist throughout the entire first year of life and, if appropriate, undergo the rehabilitative treatment at the earliest possible time. Moreover, the children with this condition must remain under the thorough follow-up care during at least 3 years including the yearly audiological evaluation and the comparative analysis of the results of previous observations for the timely identification of possible disturbances in the hearing function.

Effect of Successive Administration of Vancomycin and Amikacin on Auditory Function of Immature Animals.

Effect of successive administration vancomycin and amikacin in therapeutic doses on immature auditory organ was compared to single administration of the same drugs in chronic experiments on immature rabbits by recording of short-latency auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE). Drug administration always increased significantly the ABR peak I threshold. Ototoxic antibiotics did not change DPOAE, but selectively affected activity of outer hair cells. No enhancement of the ototoxic effects was observed after successive administration of the two antibiotics.

Auditory Function in Immature Animals after Two Consecutive Courses of Ototoxic Antibiotics.

In chronic experiments on immature rabbits receiving therapeutic courses of vancomycin, gentamicin, and consecutive administration of vancomicin and gentamicin by the scheme used in neonatology, hearing function was evaluated by the methods of auditory evoked potentials (auditory brainstem response, ABR) and distortion product otoacoustic emission (DPOAE). Comparison with the control group revealed ototoxic effects of all studied antibiotics that manifested in increased sound tolerance and more rapid shortening of latencies in 30-100 dB range. Higher thresholds were found only after gentamicin administration. Vancomycin administration significantly reduced the responses at 4 kHz. Subsequent gentamicin course did not potentiate this effect.

Effect of gentamicin on the auditory analyzer in sexually immature animals.

Auditory function of immature rabbits was evaluated using two electrophysiological methods, brainstem auditory evoked response (BAER) and distortion product otoacoustic emission (DPOAE), in chronic experiments following administration of therapeutic doses of gentamicin. Impairment of auditory function manifested in increased thresholds and decreased amplitude of the 1st BAER peak was established. DPOAE parameters were not significantly changed. It was suggested that gentamicin decreased activity of spiral ganglion neurocytes in animals with immature auditory analyzer.

Effects of amikacin on maturation of the auditory analyzer in rabbits.

We studied the dynamics of maturation of the hearing function by records of short-term latent brainstem evoked potentials and the effect of amikacin on maturation of the hearing function. The peripheral compartment of the auditory analyzer matures sooner than the central structures. Amikacin in therapeutic doses exhibited an ototoxic effect on the peripheral compartment of the auditory analyzer without impairing its central structures.