José Antônio Apparecido de Oliveira

Propofol-induced sleep: Polysomnographic evaluation of patients with obstructive sleep apnea and controls

Objective: The localization of upper airway obstruction in patients with obstructive sleep apnea (OSA) may optimize treatment. Nasoendoscopy during propofol sedation allows such an evaluation, but the effect of this drug on respiratory patterns and muscle relaxation is unknown. The objective of the present study was to determine through polysomnography whether propofol would change sleep parameters. Study Design: Prospective study of subjects submitted to polysomnography under sedation with propofol. Setting: Tertiary referral center. Subjects and Methods: Fifteen non-obese subjects (4 controls/11 OSA patients) were submitted to two diurnal polysomnograms (90-120 minutes of sleep), with and without the use of propofol. The parameters presence of snoring, apnea-hypopnea index (AHI), oxygen desaturation, and sleep architecture were compared. Results: The use of propofol did not induce snoring in the control subjects, whereas 100 percent of the OSA patients snored. AHI and mean oxygen saturation (SaO2) did not differ significantly between examinations with and without sedation. However, minimum SaO2 differed significantly (P < 0.05) with sedation, being lower during propofol sedation. Propofol also significantly changed the sleep architecture, with a significant increase in N3 sleep (P < 0.005) and total abolishment of rapid eye movement sleep (P < 0.0005) during propofol sedation. Conclusions: These preliminary results allow us to infer that sedation with propofol changes sleep architecture but permits respiratory evaluation, because the main respiratory parameters evaluated in OSA are maintained. These preliminary results support the view that nasoendoscopy under propofol sedation is a promising examination for management of this disease.

Otosclerosis: the University of Minnesota temporal bone collection.

A study of 1452 human temporal bones revealed a previously unpublished material of 144 bones with otosclerosis. After exclusion of infants and individuals of races other than white, the incidence of otosclerosis was 12.75%. Of the bones with otosclerosis, 56.1% belonged to men and 43.9% to women. The incidence of clinical and histologic otosclerosis was practically the same for men (44.7% to 55.3%) as for women (47% to 53%). However, the incidence of bilateral otosclerosis was higher in women (88.9%) than in men (65.2%). Bilateral otosclerosis was present in 75.6%, whereas it was unilateral in 24.4%. Sixty-six (66) ears (45.8%) had clinical otosclerosis, whereas 78 (54.2%) had histologic otosclerosis—frequently unifocal lesions. The most common site was anterior to the oval window (117 ears, 81.25%), followed by round window niche (52 ears, 36.11%), apical and medial cochlear wall (31 ears, 21.52%), and anterior wall of the internal auditory canal (27 ears, 18.75%). The activity of lesions was directly related to their size. Smaller lesions were predominantly inactive, whereas medium and larger lesions were predominantly active. There was a positive correlation when the size of the lesions, activity, and degree of cochlear endosteal involvement were compared with bone conduction thresholds (37 cases). Correlations between size and activity, and between activity and associated sensorineural hearing loss did not necessarily follow the sequence of an initial active stage (spongiotic) to a final inactive one (sclerotic). Comparison of cases of otosclerosis with equivalent age groups of the normal population yielded worse bone conduction thresholds for the otosclerosis cases only in the age group 60 to 69 years and older. Comparison of average bone conduction thresholds between bones with one site of endosteal involvement (28.26 dB HL) revealed no significant differences. Bones with two or more sites of endosteal involvement had significant differences. Bones with two or more sites of endosteal involvement had significantly worse bone conduction thresholds (62 dB HL). The overall results are not suggestive of an association of sensorineural hearing loss with otosclerosis without stapedial fixation.

Emissão otoacústica evocada transitória: instrumento para detecção precoce de alterações auditivas em recém-nascidos a termo e pré-termo

Introduction: The early diagnostic and intervention in the hearing alterations are of fundamental importance in the infantile development. The register of the otoacoustic emissions has been enlargement indicated for being a fast exam, easily applied. Aim: The objectives of the present study were to value the peripheral hearing function of full term neonate and adequate and small preterm neonate for the gestacional age, by the research of the transient otoacoustic emissions, identifying the prevalence of hearing alterations in this population; to verify the influence from the variable gestacional ages and weight in the moment of the birth, as well as the kinds of treatment, mechanics ventilations, administration of ototoxicity medicines and the permanence in the incubator and to analyze the factors that interfere in the programs of neonatal hearing screening. Study design: Clinical prospective. Material and method: There were appraised 157 children, whose 43 were born full term, 79 preterm adequate to gestacional age and 35 small preterm to gestacional age. It had been observed that premature neonates fail more in the answers from otoacoustic emissions. Results: The prevalence of conductive hearing impairment in the population studied was from 29 ears to 1000 and for the sensory-neural hearing impairment from the 16 to 1000. The low weight children in the birth were the most difficult to be appraised. The transient otoacoustic emissions were observed from the beginning of 27 gestacional weeks old. The kinds of treatments used were factors that influenced negatively in the answers of the otoacoustic emissions in premature groups. Conclusion: The early diagnostic work of the hearing impairment must be objective of the interdisciplinary team ¾ neonatologist, pediatrician, ear/nose and throat doctor, audiologist and speech-language pathologist, nurse and relatives ¾ and must be followed, immediately, by the early interventions programs.

Miringoplastia com a utilização de um novo material biossintético

Myringosplaty is a surgery that is performed to control infections in middle ear, to reconstruct the sound conducting mechanism for the oval window and protection of the round window. Some materials are used to reconstruct the tympanic membrane like autologous temporalis fascia, cartilage-perichondium graft taken from the tragus, cartilage only, dura mater human placental graft. It is important the vascular support to the graft with well-vascularized flap in wide perforations. AIM: The main goal of this work is shown the use of a new biomaterial, the natural latex membrane with polylysin. STUDY DESIGN: Longitudinal Cohort. MATERIAL AND METHOD: This material was developed from Department of Biochemistry from Faculdade de Medicina de Ribeirao Preto Universidade de Sao Paulo. The natural latex membrane is used stimulating neovessels and organized tecidual growing in different parts and tissues of the human body. This material promotes any allergic reaction and is innocuous to the human tissue. The 238 ears with tympanic membrane perforation resulted from chronic middle ear infection and thek was going through myringoplasty with autologous temporalis fascia and natural latex membrane. The ages were 7 to 76 years. RESULTS: The first results show 181 (90,5%) healing tympanic membrane perforation, 96 healing of wide perforation 73 medium perforation and 12 small one. Neovessels could be seen in all grafts and remaining tympanic membrane. This is not a habitual funding when the natural latex membrane is not used. CONCLUSION: According to these results we can conclude that the natural latex membrane can be used as a temporary implant in myringoplasty, improving the well vascularized of remaining tympanic membrane.

Middle Turbinate Headache Syndrome

The middle turbinate and nasal septum are innervated by the anterior ethmoidal nerve, a branch of the ophthalmic division of the trigeminal nerve. As reported in the classical work of Wolff (1948), stimulation of these regions causes pain in the medial canthus of the supraorbital region. Periorbital pain due to middle turbinate compression against the septum or the lateral wall of the nose may be due to congestion of the nasal mucosa or to pneumatization of the middle turbinate (concha bullosa). The diagnosis is made by exclusion and requires a high index of suspicion, anterior rhinoscopy, computerized tomography (CT), and confirmation by the lidocaine test. We present five cases of middle turbinate headache syndrome, all with contha bullosa. Four were treated surgically by partial middle turbinectomy and septoplasty more than 1 year ago, with excellent results. One patient refused surgical treatment which was suggested after failure of medical treatment with antihistamines, decongestants, and a topical corticosteroid, and continues to be symptomatic. Despite the small number of cases studied, the authors conclude that the procedure used was effective for the resolution of headache.

Gentamicin Attenuates Gentamicin-Induced Ototoxicity - Self-Protection

Aminoglycoside antibiotics cause considerable toxicity to the inner ear. A progressive hearing loss at high frequencies resulted from the loss of hair cells in the base of the cochlea and a constant preoccupation with finding a treatment that protects against their toxic effects. A self-protection phenomenon to high ototoxic doses of gentamicin is proposed in this paper. Thirty-eight adult guinea pigs with normal hearing were tested using Preyers reflex and the distortion product otoacoustic emission (DPOAE) test, and their cochleae were analyzed by scanning electron microscopy. To the four groups investigated, group I (control) and group II (low dose, 10 mg/kg/day for 30 days) showed a normal DPOEA and normal outer hair cells; group III (high dose, 160 mg/kg/day for 10 days) showed the absence of DPOEA and damage to the outer hair cells; and group IV (low dose, 10 mg/kg/day for 30 days followed by a high dose of 160 mg/kg/day for 10 days) showed a normal DPOEA and normal outer hair cells. These results demonstrate that there was a considerable self-protection phenomenon by gentamicin.

Ototoxicity and otoprotection in the inner ear of guinea pigs using gentamicin and amikacin: ultrastructural and functional aspects

UNLABELLED Ototoxicity is still a challenge to medicine. The discovery of self-protecting endogenous mechanisms of the outer hair cells associated with their functional and ultra-structural assessment methods has opened new horizons in the understanding and controlling of these mechanisms. AIM this paper aimed at establishing whether or not underdoses of gentamicin could protect the inner ear against the harmful effects of amikacin, based on these protection mechanisms and determine if the otoacoustic emission amplitudes could be associated with the level of hair cell integrity. MATERIALS AND METHODS Experimental study. We used 31 guinea pigs. They were injected with saline solution, gentamicin and amikacin, alone and in combinations -intramuscular injections - during 12, 30 and 42 days. The otoacoustic emissions were recorded in the beginning and at the end of the experiment, comparing it with the cochlear integrity study carried out by electron microscopy. RESULTS gentamicin underdoses did not protect the inner ear against amikacin toxicity; the reduction in otoacoustic emissions was strongly associated with an increase in hair cell lesions. CONCLUSION these findings help understand inner ear otoprotection and ototoxicity. Establishing the correlation between the emissions amplitude an cell integrity plays an important role in the follow up of hair cell damage, with possible monitoring of ototoxicity caused by drugs in humans.

Ototoxicidade e otoproteção em orelha interna de cobaias utilizando gentamicina e amicacina: aspectos ultra-estruturais e funcionais

A ototoxicidade ainda e um desafio para medicina. A descoberta dos mecanismos endogenos autoprotetores das celulas ciliadas externas associados a metodos de avaliacao funcional e ultra-estrutural das mesmas abriu nova perspectiva no entendimento e controle destes mecanismos. OBJETIVO: O trabalho objetivou determinar se subdoses de gentamicina protegia contra ototoxicidade da amicacina baseado nestes mecanismos e determinar se a amplitude das emissoes otoacusticas teria correlacao com grau de integridade das celulas ciliadas. MATERIAL E METODO: Estudo experimental. Utilizando 31 cobaias, administrou-se soro fisiologico, gentamicina e amicacina, isoladamente e associadas, via intramuscular, por 12, 30 e 42 dias. Pesquisa de emissoes otoacusticas foi realizada no inicio e final do experimento, comparado com estudo da integridade coclear, por microscopia eletronica. RESULTADOS: Subdoses de gentamicina nao protegeram a orelha interna contra toxicidade da amicacina; diminuicoes da amplitude das emissoes otoacusticas apresentaram forte correlacao com aumento de lesoes das celulas ciliadas. CONCLUSAO: Os achados contribuem para o entendimento dos mecanismos de ototoxicidade e otoprotecao da orelha interna. A determinacao da correlacao entre amplitude de emissoes e integridade celular tem grande importância no acompanhamento das lesoes de celulas ciliadas, com possivel aplicacao no monitoramento de ototoxicidade por drogas em humanos.

Biosilicate® Ototoxicity and Vestibulotoxicity evaluation in guinea-pigs

UNLABELLED Changes, destructions and interruptions in middle ear ossicular chain architecture may be caused by infection, trauma, tumors, congenital alterations or prior surgeries. Nonetheless, infectious and inflammatory processes, focal or generalized which affect the middle ear are the most prevalent, causing a great demand for ossiculoplasty. Biosilicato is a new material which can be used in the middle ear with the goal of reconstructing the ossicular chain. It is a bioactive type A vitroceramic, in other words, it binds to bone or soft tissue in a matter of a few hours, thanks to the formation of hydroxy-carbonateapatatie in its contact surface when in contact with body fluids. AIMS The goal of the present paper is to assess biosilicate ototoxicity and vestibular toxicity in experimental animals, for later use in humans. MATERIALS AND METHODS This a clinical and experimental study in which otoacoustic emissions were performed before and after the placement of Biosilicate in the middle ear of experimental animals and a scanning electron microscopy was carried out in the cochlea, saccule, utriculus and macula of the semicircular canals after 30 and 90 days to assess oto and vestibular toxicity. RESULTS There were no signs of oto or vestibular toxicity in any of the groups associated with biosilicate. CONCLUSION Biosilicate is a safe material to be used in ossiculoplasties.

The role of hyperbaric oxygen therapy (HOT) as an otoprotection agent against cisplatin ototoxicity

PURPOSE Hyperbaric oxygen therapy (HOT) consists of intermittent inhalations of 100% oxygen at a pressure higher than 1 atm. It is an important adjuvant therapy in pathological processes like soft tissue infections, radiation injury, gas gangrene, osteomyelitis and decompressive diseases. Cisplatin, a potent antineoplastic drug, widely used in cancer therapy is highly ototoxic causing bilateral, irreversible damage to the hearing of high frequency sounds (4-8 KHz). OBJECTIVE This experimental study conducted at the Faculty of Medicine of Ribeirao Preto, University of Sao Paulo aims to evaluate Hyperbaric Oxygen Therapy as an otoprotection agent against drug toxicity. METHODS Albino guinea pigs were divided into two groups: in Group A, 5 animals (10 cochlea) received cisplatin, i. p., 8.0 mg/kg/day during three days and afterwards were submitted to HOT; in Group B, 3 animals (6 cochlea) received cisplatin, i. p. 8.0 mg/kg/day during three days. Guinea pigs were evaluated by acoustic otoemissions (AOE) and scanning electron microscopy (SEM). RESULTS Group B animals showed loss of auditory functions as measured by AOE and distorted outer hair cells by SEM. In Group A, outer hair cells shown by SEM images were mostly preserved. CONCLUSION It is presumed that Hyperbaric Oxygen Therapy has a protector effect against cisplatin ototoxicity.