Fogo em campo cirúrgico - Medidas preventivas para cirurgia palpebral segura / Operating room fire prevention - preventive measures for safe eyelid surgery

Resumo Fogo em campo cirúrgico durante cirurgia palpebral é uma complicação intra-operatória que é dramática tanto para o paciente quanto para a equipe médica. Relatamos um caso de acidente cirúrgico durante cirurgia palpebral onde o paciente sofreu queimadura de supercílio. Houve interação entre o oxigênio usado para sedação (máscara aberta) e uma fonte de ignição representada pelo cautério monopolar. Embora o paciente tenha apresentado boa evolução clínica com recuperação total da lesão cutânea, este caso é um alerta para se evitar tais tipo de ocorrência. Ressaltamos neste trabalho quais as condições implicadas e o modo de prevenção.

Abstract Fire in the surgical field during eyelid surgery is an intra-operative complication that is dramatic for both the patient and the medical staff. It's being reported a case of surgical accident during eyelid surgery where the patient suffered a brow burn. There was interaction between the oxygen used for sedation (open mask) and a source of ignition represented by monopolar cautery. Although the patient presented good clinical evolution with complete recovery of the cutaneous lesion, this case is an alert to avoid such type of occurrence. This work highlights the conditions involved and the way of prevention.

Effect of unilateral amygdalotomy and hypothalamotomy in patients with refractory aggressiveness.

BACKGROUND: Neurosurgical treatment, although controversial, is considered a useful resource in the treatment of chronic psychiatric diseases such as refractory aggressiveness. OBJECTIVE: To evaluate the clinical results and side effects of posteromedial hypothalamotomy associated with amygdalotomy in patients with refractory aggressiveness. METHOD: A clinical trial was conducted in patients with chronic aggressiveness and refractory to pharmacological treatment. A central amygdalotomy associated with posteromedial hypothalamotomy was performed using thermo-coagulation by radiofrequency. The degree of aggressiveness was quantified by the Yudofsky's global scale of aggression. Postoperative changes in aggressive behavior continued to be evaluated every 6 months for at least 36 months. RESULTS: A statistically significant change in aggressive behavior was observed during 36 months of follow-up. The collateral effects of the association of both procedures are described, the most frequent being drowsiness and some cases of reduction in sexual behavior. CONCLUSION: Symmetric and simultaneous unilateral lesions of the central nucleus of the amygdala and the posteromedial hypothalamus contralateral to motor dominance give the same clinical effect in the reduction of the pathological aggression that the bilateral lesions.

Evaluation of temperature induction in focal ischemic thermocoagulation model.

The thermocoagulation model, which consists of focal cerebral ischemia with craniectomy, is helpful in studying permanent ischemic brain lesions and has good reproducibility and low mortality. This study analyzed the best conditions for inducing a focal ischemic lesion by thermocoagulation. We investigated parameters such as temperature and thermal dissipation in the brain tissue during induction and analyzed real-time blood perfusion, histological changes, magnetic resonance imaging (MRI), and motor behavior in a permanent ischemic stroke model. We used three-month-old male Wistar rats, weighing 300-350 g. In the first experiment, the animals were divided into four groups (n = 5 each): one sham surgery group and three ischemic lesion groups having thermocoagulation induction (TCI) temperatures of 200°C, 300°C, and 400°C, respectively, with blood perfusion (basal and 30 min after TCI) and 2,3,5-Triphenyl-tetrazolium chloride (TTC) evaluation at 2 h after TCI. In the second experiment, five groups (n = 5 each) were analyzed by MRI (basal and 24 h after TCI) and behavioral tests (basal and seven days after TCI) with the control group added for the surgical effects. The MRI and TTC analyses revealed that ischemic brain lesions expressively evolved, especially at TCI temperatures of 300°C and 400°C, and significant motor deficits were observed as the animals showed a decrease frequency of movement and an asymmetric pattern. We conclude that a TCI temperature of 400°C causes permanent ischemic stroke and motor deficit.

American cutaneous leishmaniasis triggered by electrocoagulation.

Cutaneous leishmaniasis is usually transmitted by infected phlebotomine sand fly bites that initiate local cutaneous lesions. Few reports in the literature describe other modes of transmission. We report a case of a previously healthy 59-year-old woman who underwent electrocoagulation to remove seborrheic keratosis confirmed by dermatoscopy. Three months later, a skin fragment tested positive for Leishmania culture; the parasite was identified as L. (V.) braziliensis. Trauma may generate inflammatory cascades that favor Leishmania growth and lesion formation in previously infected patients. American cutaneous leishmaniasis is a dynamic disease with unclear pathophysiology because of continually changing environments, demographics, and human behaviors.

American cutaneous leishmaniasis triggered by electrocoagulation

Abstract Cutaneous leishmaniasis is usually transmitted by infected phlebotomine sand fly bites that initiate local cutaneous lesions. Few reports in the literature describe other modes of transmission. We report a case of a previously healthy 59-year-old woman who underwent electrocoagulation to remove seborrheic keratosis confirmed by dermatoscopy. Three months later, a skin fragment tested positive for Leishmania culture; the parasite was identified as L. (V.) braziliensis. Trauma may generate inflammatory cascades that favor Leishmania growth and lesion formation in previously infected patients. American cutaneous leishmaniasis is a dynamic disease with unclear pathophysiology because of continually changing environments, demographics, and human behaviors.

Prospective, double-blind, randomized controlled trial comparing electrocoagulation and radiofrequency in the treatment of patients with great saphenous vein insufficiency and lower limb varicose veins.

OBJECTIVE: Thermoablation has been replacing conventional surgery in the surgical treatment of great saphenous vein (GSV) reflux in patients with lower limb varicose veins; however, thermoablation is expensive. Intravenous electrocoagulation (EC) may, selectively and safely, cause necrosis of the GSV wall, but the clinical results have never been studied. The objective of this study was to compare EC and radiofrequency ablation (RFA) in the treatment of GSV insufficiency, considering efficacy, complications, and effect on quality of life. METHODS: This was a prospective, double-blind, randomized clinical trial. Patients with lower limb varicose veins and GSV reflux confirmed by duplex ultrasound were randomized into two treatment groups: EC and RFA. Patients were followed up at 1 week, 3 months, and 6 months after the procedure. Occlusion of the GSV confirmed by duplex ultrasound was considered the primary outcome, and the rate of complications and improvement in quality of life, using the Aberdeen Varicose Vein Questionnaire score, were the secondary outcomes. RESULTS: Fifty-seven patients were included, with a total of 85 treated GSVs; 43 were treated with RFA and 42 with EC. There was no statistically significant difference between the groups regarding age (P = .264), sex (P = .612), Aberdeen Varicose Vein Questionnaire score (P = .054), and diameter (P = .880) and depth (P = .763) of the treated GSV. In the intraoperative period, immediately after thermoablation, all GSVs treated with EC presented no flow and incompressibility in the treated segment, whereas 12 limbs still had flow in the treated GSV (P < .001) and 9 veins showed compressibility (P < .001) when treated with RFA. The main postoperative complication was paresthesia; however, there was no statistical significance between the groups (P = .320) regarding its presence. Time to return to routine activities was lower in the EC group than in the RFA group (P = .026). There was no difference between the groups at the 3-month (P = .157) and 6-month (P = .157) follow-up in occlusion of the GSV and improvement of the quality of life score (P = .786 and P = .401, respectively). CONCLUSIONS: EC has been shown to be an effective method for ablation of the GSV, with venous occlusion rate, occurrence of complications, and effect on quality of life similar to those with RFA.

Systematic review and meta-analysis of the effect of bipolar electrocoagulation during laparoscopic ovarian endometrioma stripping on ovarian reserve.

BACKGROUND: Laparoscopic stripping is the gold-standard treatment for ovarian endometriosis. The choice of hemostasis method might affect ovarian reserve. OBJECTIVES: To determine whether bipolar electrocoagulation is more detrimental to ovarian reserve than non-thermal hemostasis methods. SEARCH STRATEGY: Entry terms associated with the MeSH terms "endometrioma," "laparoscopy," and "ovarian reserve" were used to search databases for articles published up to April 3, 2017, in English, Spanish, Portuguese, French, and Italian. SELECTION CRITERIA: Randomized controlled trials comparing the 3-month postoperative serum anti-Müllerian hormone (AMH) level in premenopausal women undergoing laparoscopic stripping with bipolar hemostasis or non-thermal hemostasis methods were selected. DATA COLLECTION AND ANALYSIS: Data were extracted by two independent reviewers and a meta-analysis was performed. MAIN RESULTS: Three studies met the inclusion criteria; overall, 105 patients underwent surgery with bipolar electrocoagulation and 105 patients underwent surgery with an alternative hemostasis method. The AMH level 3 months after surgery was decreased in the bipolar electrocoagulation group (mean difference -0.79 ng/mL, 95% confidence interval -1.19 to -0.39). CONCLUSIONS: Bipolar electrocoagulation negatively impacts ovarian reserve and should be avoided, especially for patients with reproductive goals.

Separating the Laparoscopic Camera Cord From the Monopolar "Bovie" Cord Reduces Unintended Thermal Injury From Antenna Coupling: A Randomized Controlled Trial.

OBJECTIVE(S): The monopolar "Bovie" is used in virtually every laparoscopic operation. The active electrode and its cord emit radiofrequency energy that couples (or transfers) to nearby conductive material without direct contact. This phenomenon is increased when the active electrode cord is oriented parallel to another wire/cord. The parallel orientation of the "Bovie" and laparoscopic camera cords cause transfer of energy to the camera cord resulting in cutaneous burns at the camera trocar incision. We hypothesized that separating the active electrode/camera cords would reduce thermal injury occurring at the camera trocar incision in comparison to parallel oriented active electrode/camera cords. METHODS: In this prospective, blinded, randomized controlled trial, patients undergoing standardized laparoscopic cholecystectomy were randomized to separated active electrode/camera cords or parallel oriented active electrode/camera cords. The primary outcome variable was thermal injury determined by histology from skin biopsied at the camera trocar incision. RESULTS: Eighty-four patients participated. Baseline demographics were similar in the groups for age, sex, preoperative diagnosis, operative time, and blood loss. Thermal injury at the camera trocar incision was lower in the separated versus parallel group (31% vs 57%; P = 0.027). CONCLUSIONS: Separation of the laparoscopic camera cord from the active electrode cord decreases thermal injury from antenna coupling at the camera trocar incision in comparison to the parallel orientation of these cords. Therefore, parallel orientation of these cords (an arrangement promoted by integrated operating rooms) should be abandoned. The findings of this study should influence the operating room setup for all laparoscopic cases.

Effect of lithium on behavioral disinhibition induced by electrolytic lesion of the median raphe nucleus.

RATIONALE: Alterations in brainstem circuits have been proposed as a possible mechanism underlying the etiology of mood disorders. Projections from the median raphe nucleus (MnR) modulate dopaminergic activity in the forebrain and are also part of a behavioral disinhibition/inhibition system that produces phenotypes resembling behavioral variations manifested during manic and depressive phases of bipolar disorder. OBJECTIVE: The aim of this study is to assess the effect of chronic lithium treatment on behavioral disinhibition induced by MnR lesions. METHODS: MnR electrolytic lesions were performed in C57BL/6J mice, with sham-operated and intact animals as control groups. Following recovery, mice were chronically treated with lithium (LiCl, added in chow) followed by behavioral testing. RESULTS: MnR lesion induced manic-like behavioral alterations including hyperactivity in the open field (OF), stereotyped circling, anxiolytic/risk taking in the elevated plus maze (EPM) and light/dark box (LDB) tests, and increased basal body temperature. Lithium was specifically effective in reducing OF hyperactivity and stereotypy but did not reverse (EPM) or had a nonspecific effect (LDB) on anxiety/risk-taking measures. Additionally, lithium decreased saccharin preference and prevented weight loss during single housing. CONCLUSIONS: Our data support electrolytic lesions of the MnR as an experimental model of a hyper-excitable/disinhibited phenotype consistent with some aspects of mania that are attenuated by the mood stabilizer lithium. Given lithium's relatively specific efficacy in treating mania, these data support the hypothesis that manic symptoms derive not only from the stimulation of excitatory systems but also from inactivation or decreased activity of inhibitory mechanisms.

Urological fistulas after fetal cystoscopic laser ablation of posterior urethral valves: surgical technical aspects.

OBJECTIVE: To describe the surgical technical aspects associated with the development of urological fistulas after fetal antegrade cystoscopic laser fulguration of the posterior urethral valves (PUV). METHODS: The perioperative data for all fetal cystoscopies performed between January 2004 and August 2013 at three institutions in the USA, France and Brazil were reviewed, with particular emphasis on surgical technical aspects of the procedure and the complications encountered. RESULTS: A total of 40 fetal cystoscopies were performed at the three institutions. Laser fulguration of the PUV was performed in 23 of these cases, with a survival rate of 60.9% (14/23) and normal renal function in 85.7% (12/14) of these infants. Urological fistulas were diagnosed postnatally in four (10%) newborns. The presence of fistulas was associated with a higher gestational age at diagnosis of PUV (P < 0.01) and with the use of semi-curved rather than curved sheaths (P < 0.01), the use of a diode laser (P < 0.01) and the use of higher laser power and energy (P < 0.01 and P < 0.01, respectively), as well as with less operator experience (P < 0.01) and with absence of fetal anesthesia/immobilization (P = 0.02). CONCLUSION: Urological fistulas are a severe complication of fetal cystoscopic laser fulguration of PUV and are associated with type, energy and power settings of the laser and instrumentation. The use of appropriate technique and proper training of the operator are necessary to perform this fetal intervention safely.

Use of electrocautery for coagulation and wound complications in Caesarean sections.

OBJECTIVE: To evaluate the safety of electrocautery for coagulation during Caesarean sections. STUDY DESIGN: A randomized, controlled, clinical pilot study was performed at a university maternity hospital. After admission for delivery and decision to perform a C-section, volunteers were randomized to either the intervention group (use of electrocautery for coagulation) or nonintervention group. The women were examined at the time of postpartum discharge (day 3), at days 7 to 10, and again at days 30 to 40 for signs of infection, hematoma, seroma, or dehiscence. Data were analyzed using an intention-to-treat analysis, and risk ratios were calculated. RESULTS: No significant differences were found between the two groups. Only 2.8% of patients in the intervention group developed surgical wound complications during hospitalization. However, 7 to 10 days following discharge, these rates reached 23.0% and 15.4% in the intervention and nonintervention groups, respectively (RR = 1.50, 95% CI = 0.84-2.60). CONCLUSION: Further studies should confirm whether the use of electrocautery for coagulation does not increase the risk of surgical wound complications in patients undergoing Caesarean sections.

Surgical site infection: an observer-blind, randomized trial comparing electrocautery and conventional scalpel.

AIM: To evaluate the incidence of surgical site infection (SSI) based on the type of scalpel used for incisions in the skin and in subcutaneous tissues. METHODS: Observer-blind, randomized equivalence clinical trial with two arms (electrocautery versus conventional scalpel) which evaluated 133 women undergoing elective abdominal gynecologic oncology surgery. A simple randomization stratified by body mass index (BMI: 30 kg/m(2)) was carried out. Women were evaluated at 14 and 30 days following the operation. A multivariate analysis was performed in order to check whether the type of scalpel would be a risk factor for SSI. RESULTS: Group arms were balanced for all variables, excepted for surgical time, which was significantly higher in the electrocautery group (mean: 161.1 versus 203.5 min, P = 0.029). The rates of SSI were 7.4% and 9.7%, respectively, for the conventional scalpel and electrocautery groups (P = 0.756). The exploratory multivariate model identified body mass index ≥30 kg/m(2) (OR = 24.2, 95% CI: 2.8-212.1) and transverse surgical incision (OR = 8.1, 95% CI: 1.5-42.6) as independent risk factors for SSI. The type of scalpel used in surgery, when adjusted for these variables and the surgery time, was not a risk factor for SSI. CONCLUSION: This study showed that the SSI rates for conventional scalpel and electrocautery were not significantly different. These results were consistent with others reported in the literature and would not allow a surgeon to justify scalpel choice based on SSI. TRIAL NUMBER: NCT01410175 (Clinical Trials - NIH).

The potential therapeutic effect of guanosine after cortical focal ischemia in rats.

BACKGROUND AND PURPOSE: Stroke is a devastating disease. Both excitotoxicity and oxidative stress play important roles in ischemic brain injury, along with harmful impacts on ischemic cerebral tissue. As guanosine plays an important neuroprotective role in the central nervous system, the purpose of this study was to evaluate the neuroprotective effects of guanosine and putative cerebral events following the onset of permanent focal cerebral ischemia. METHODS: Permanent focal cerebral ischemia was induced in rats by thermocoagulation. Guanosine was administered immediately, 1 h, 3 h and 6 h after surgery. Behavioral performance was evaluated by cylinder testing for a period of 15 days after surgery. Brain oxidative stress parameters, including levels of ROS/RNS, lipid peroxidation, antioxidant non-enzymatic levels (GSH, vitamin C) and enzymatic parameters (SOD expression and activity and CAT activity), as well as glutamatergic parameters (EAAC1, GLAST and GLT1, glutamine synthetase) were analyzed. RESULTS: After 24 h, ischemic injury resulted in impaired function of the forelimb, caused brain infarct and increased lipid peroxidation. Treatment with guanosine restored these parameters. Oxidative stress markers were affected by ischemic insult, demonstrated by increased ROS/RNS levels, increased SOD expression with reduced SOD activity and decreased non-enzymatic (GSH and vitamin C) antioxidant defenses. Guanosine prevented increased ROS/RNS levels, decreased SOD activity, further increased SOD expression, increased CAT activity and restored vitamin C levels. Ischemia also affected glutamatergic parameters, illustrated by increased EAAC1 levels and decreased GLT1 levels; guanosine reversed the decreased GLT1 levels and did not affect the EAAC1 levels. CONCLUSION: The effects of brain ischemia were strongly attenuated by guanosine administration. The cellular mechanisms involved in redox and glutamatergic homeostasis, which were both affected by the ischemic insult, were also modulated by guanosine. These observations reveal that guanosine may represent a potential therapeutic agent in cerebral ischemia by preventing oxidative stress and excitotoxicity.

Fuego quirúrgico: un incidente prevenible / Surgical fire: an avoidable incident

Introduction: surgical fire requires the presence of three components, known as the "fire triad": a fuel, an ignition source and an oxidizer. Clinical case: we report a patient who, during an ambulatory surgery, suffered a facial burn from a fire. The use of an electrosurgical unit and supplementary oxygen through nasal cannula were important factors in this case. We describe how and why fire start, which are the high-risk surgeries and the strategies to reduce the risk of fire in surgical patients.

Introducción: el fuego quirúrgico requiere tres elementos para que se produzca, conocidos como "triada de fuego": un combustible, una fuente de ignición y un oxidante. Caso clínico: presentamos el caso de una paciente que sufrió una quemadura facial por fuego durante una cirugía ambulatoria, en la que fueron factores importantes el uso de una unidad electroquirúrgica y la administración de oxígeno a través de una cánula nasal. Describimos cómo y por qué se puede producir fuego, cuáles son las cirugías de alto riesgo y las estrategias para reducir el riesgo de fuego en pacientes quirúrgicos.

[Respiratory symptoms caused by the use of electrocautery in physicians being trained in surgery in a Mexican hospital]. / Síntomas respiratorios causados por el uso del electrocauterio en médicos en formación quirúrgica de un hospital de México.

In order to determine the frequency of respiratory symptoms among residents from surgical specialties dures exposed to the electrocautery smoke, a cross-sectional study was conducted in February 2012. 50 third-year residents from different surgical specialties coming from a third-level hospital belonging to the Institute of Security and Social Services of the State Workers in Jalisco, Mexico, were included. The subject selection was non-probabilistic. A questionnaire on respiratory symptoms developed in Cuba was used for data collection. The most common symptoms were sensation of a lump in the throat (58%), and a sore throat (22%). The specialty with the highest rate of exposure was neurosurgery (24.1 min/surgical procedure). All, the physicians from this specialty had respiratory symptoms. We conclude that the cauterization smoke may be considered a risk for developing respiratory symptoms among physicians with surgical specialties.

Síntomas respiratorios causados por el uso del electrocauterio en médicos en formación quirúrgica de un hospital de México / Respiratory symptoms caused by the use of electrocautery in physicans being trained in surgery in a Mexican hospital

Con el objetivo de determinar la frecuencia de síntomas respiratorios entre los residentes de especialidades quirúrgicas expuestos al humo del electrocauterio, se realizó un estudio transversal durante el mes de febrero de 2012. Se incluyeron 50 médicos residentes del tercer año, de diferentes especialidades quirúrgicas, de un hospital de tercer nivel perteneciente al Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado ubicado en Jalisco, México. La selección de sujetos fue no probabilística. Para la recolección de datos, se empleó el cuestionario de síntomas respiratorios desarrollado en Cuba. Los síntomas más comunes fueron sensación de cuerpo extraño (58%) y ardor faríngeo (22%). La especialidad con mayor índice de exposición fue la de neurocirugía (24,1 min/acto quirúrgico). La totalidad de los médicos de esta especialidad tuvieron algún síntoma respiratorio. Se concluye que la inhalación del humo del cauterio puede constituir un riesgo para desarrollar síntomas respiratorios entre los médicos de especialidades quirúrgicas.

In order to determine the frequency of respiratory symptoms among residents from surgical specialties dures exposed to the electrocautery smoke, a cross-sectional study was conducted in February 2012. 50 third-year residents from different surgical specialties coming from a third-level hospital belonging to the Institute of Security and Social Services of the State Workers in Jalisco, Mexico, were included. The subject selection was non-probabilistic. A questionnaire on respiratory symptoms developed in Cuba was used for data collection. The most common symptoms were sensation of a lump in the throat (58%), and a sore throat (22%). The specialty with the highest rate of exposure was neurosurgery (24.1 min/surgical procedure). All, the physicians from this specialty had respiratory symptoms. We conclude that the cauterization smoke may be considered a risk for developing respiratory symptoms among physicians with surgical specialties.

Assessing cochlear evoked potentials after electrocautery-induced trauma to the utricle.

UNLABELLED: Utriculostomy is a new surgical alternative for Ménière's disease. The basis of this procedure is that the outcome of an electrocautery-induced utricular trauma does not affect cochlear function. However, a demonstration of the hypothesis that this approach to the utricle would preserve hearing is still pending. OBJECTIVE: To determine whether any changes would occur in the electrical potentials evoked in the cochlea and auditory nerve before, during, and 1 month after a surgical procedure in the utricule in an animal model. MATERIALS AND METHODS: An experimental study. Eight sheep underwent electrocautery-induced utricular trauma, and their cochlear function was assessed by electrocochleography--recording of electrical evoked potentials, in the preoperative, immediate postoperative and medium-term postoperative periods. The results were analyzed statistically. RESULTS: There were no statistically significant variations in amplitude (p = 0.099) and latency (p = 0.591) before and 1 month after the surgical procedure. There was a statistically significant change in the summation of the potential/action potential area ratio (p = 0.0122), a calculated loss of 11.8 dB. CONCLUSION: The intervention performed in this study enabled us to conclude that, taking into account the impaired electrophysiological responses observed during and 1 month after the surgical procedure, hearing was preserved in the operated sheep.

Avaliação dos potenciais evocados cocleares após lesão do utrículo por eletrocauterização / Assessing cochlear evoked potentials after electrocautery-induced trauma to the utricle

A utriculostomia é uma nova alternativa cirúrgica para a doença de Ménière. A hipótese cirúrgica desse procedimento é a de que o desfecho de uma lesão do utrículo por eletrocauterização não interfere na função coclear. Contudo, a hipótese de que essa abordagem do utrículo preserva a audição ainda não foi comprovada. OBJETIVO: Determinar se ocorrem mudanças nos potenciais elétricos evocados na cóclea e no nervo auditivo antes, durante e 1 mês após o procedimento cirúrgico no utrículo em modelo animal. MATERIAIS E MÉTODOS: Estudo experimental: Oito ovelhas foram submetidas à lesão do utrículo por eletrocauterização e sua função coclear foi avaliada por meio de eletrococleografia, registrando-se os potenciais elétricos evocados nos períodos pré-operatório, pós-operatório imediato e pós-operatório de médio prazo. Os resultados foram analisados estatisticamente. RESULTADOS: Não houve variação estatisticamente significativa na amplitude (p = 0,099) e na latência (p = 0,591) antes e 1 mês após o procedimento cirúrgico. Houve alteração estatisticamente significativa na razão entre potencial de somação/potencial de ação (p = 0,0122), representando uma perda calculada de 11,8 dB. CONCLUSÃO: A intervenção realizada no utrículo neste estudo permite concluir que, tendo em conta respostas eletrofisiológicas deficientes observadas durante e 1 mês após o procedimento cirúrgico, houve preservação da audição nas ovelhas operadas.

Utriculostomy is a new surgical alternative for Ménière's disease. The basis of this procedure is that the outcome of an electrocautery-induced utricular trauma does not affect cochlear function. However, a demonstration of the hypothesis that this approach to the utricle would preserve hearing is still pending. OBJECTIVE: To determine whether any changes would occur in the electrical potentials evoked in the cochlea and auditory nerve before, during, and 1 month after a surgical procedure in the utricule in an animal model. MATERIALS AND METHODS: An experimental study. Eight sheep underwent electrocautery-induced utricular trauma, and their cochlear function was assessed by electrocochleography - recording of electrical evoked potentials, in the preoperative, immediate postoperative and medium-term postoperative periods. The results were analyzed statistically. RESULTS: There were no statistically significant variations in amplitude (p = 0.099) and latency (p = 0.591) before and 1 month after the surgical procedure. There was a statistically significant change in the summation of the potential/action potential area ratio (p = 0.0122), a calculated loss of 11.8 dB. CONCLUSION: The intervention performed in this study enabled us to conclude that, taking into account the impaired electrophysiological responses observed during and 1 month after the surgical procedure, hearing was preserved in the operated sheep.