Objective. Sudden hearing loss (SHL) is a frightening symptom that often prompts an urgent or emergent visit to a physician. This guideline provides evidence-based recommendations for the diagnosis...

/pdf/clinical-practice-guideline-sudden-hearing-loss-8acwe9fo8a.pdf

Clinical practice guideline: sudden hearing loss.

Malignant otitis externa.

Objectives:

To study the safety and efficacy of continuous intratympanic dexamethasone-phosphate (Dex-P) for severe to profound sudden idiopathic sensorineural hearing (ISSHL) or sudden idiopathic anacusis after failure of systemic therapy.



Study Design:

Randomized, double-blind, placebo controlled multicenter trial.



Methods:

Patients with ISSHL and insufficient recovery (mean 4PTA = 97 dB HL) after systemic high dose glucocorticoid therapy received either Dex-P (4mg/ml) or placebo (NaCl 0.9%) continuously applied for 14 days into the round window niche via a temporarily implanted catheter. For ethical reasons, intratympanic treatment was continued with Dex-P in all patients for another 14 days after the placebo-controlled study period. According to a two-step adaptive study design an interim analysis was performed after inclusion of 23 patients.



Results:

Intention-to-treat analysis for the primary outcome criterion (4PTA: 0.5-3kHz) during the placebo controlled study period (14 days) showed an average hearing improvement in the treatment group of 13.9 dB (SD: 21.3) and in the placebo group of 5.4 dB (SD: 10.4). This difference in hearing improvement between the two groups (mean: 8.4 dB, SD: 17.0, 95% CI: −7.1–24.1) was statistically not significant (p = .26). Of the secondary outcome parameters, the largest benefit of local salvage therapy was found for maximum speech discrimination with an improvement of 24.4% (SD: 32.0) in the treatment and 4.5% (SD: 7.6) in the placebo group (p = 0.07). After a 3 month follow-up period (i.e. after all patients received intratympanic Dex-P) hearing improvement in the two groups was very similar. No serious adverse events were observed. Sample size calculation after the interim analysis resulted in stopping of the trial.



Conclusions:

The tendency toward better hearing improvement in the treatment group, the rather conservative inclusion criteria, the limited placebo-controlled observation period and the absence of serious adverse events supports further investigation local inner ear drug delivery as a first or second line treatment option for ISSHL. Laryngoscope, 119:359–369, 2009

Randomized, double blind, placebo controlled trial on the safety and efficacy of continuous intratympanic dexamethasone delivered via a round window catheter for severe to profound sudden idiopathic sensorineural hearing loss after failure of systemic therapy.

Within the scope of this book, a review is presented regarding general characteristics of gases: constants, pressure and density, composition of air, and characteristics of oxygen, nitrogen and carbon dioxide as major components of air. Relevant information is given regarding the basic gas laws of Boyle and Amontons, the universal gas equation, the gas laws of Dalton and Henry and the laws of diffusion (Fick). In addition the principle of adiabatic processes (Joule-Thomson effect and adiabatic decompression) is described

Handbook on Hyperbaric Medicine

https://www.emed.theclinics.com/article/S0733-8627(08)00006-0/pdf

Hyperbaric oxygen: applications in infectious disease.

OBJECTIVE We investigated the effect of pharmacologic (steroids, vasodilators, vitamins, and Betaserc) and hyperbaric oxygen therapy on patients with sudden sensorineural hearing loss. METHODS The pharmacologic arm of the study consisted of 52 patients with defined sudden sensorineural hearing loss treated simultaneously in the ENT Department and National Center for Hyperbaric Medicine of the Medical University of Gdansk, Poland, from 1997 to 2000 (Group A). The hyperbaric oxygen therapy consisted of exposure to 100% oxygen at a pressure of 250 kPa for a total of 60 minutes in a multiplace hyperbaric chamber. The control group included 81 patients with defined sudden sensorineural hearing loss treated in the ENT Department, Medical University of Gdansk, from 1980 to 1996 (Group B). Both groups were comparable regarding the age of the patients, season of hearing loss occurrence, tinnitus and vestibular symptom frequency, delay before therapy, and average threshold loss before the start of treatment. The treatment results (hearing gain) were estimated using pure-tone audiometry. We retrospectively analyzed the audiograms of all patients. RESULTS Patients from Group A (blood flow-promoting drugs, glucocorticoids in high doses, betahistine, and hyperbaric oxygen therapy) showed significantly better recovery of hearing levels compared with those from Group B (blood flow-promoting drugs and glucocorticoids in low doses) at seven frequencies (500, 1,000, 2,000, 3,000, 4,000, 6,000, and 8,000 Hz) (p < 0.05) and four groups of frequencies (pure-tone average, high-tone average, pure middle-tone average, and overall average) (p < 0.05). Percentage hearing gain in all investigated frequencies was also better in Group A versus Group B, and the differences were statistically significant (p < 0.05). CONCLUSION We conclude that hyperbaric oxygen therapy with high doses of glucocorticoids improves the results of conventional sudden sensorineural hearing loss treatment and should be recommended. In addition, the best results are achieved if the treatment is started as early as possible.

Usefulness of high doses of glucocorticoids and hyperbaric oxygen therapy in sudden sensorineural hearing loss treatment.

Malignant external otitis (MEO) is an invasive, morbidity, even mortality, mainly pseudomonal infection of the external auditory canal, frequently involving the base of the skull, multiple cranial nerve and the meninges. In many cases conventional therapy has been prolonged, intensive and relatively ineffective, especially in infections other than bacterial (mainly fungal). We presented theoretical principles of hyperbaric oxygen (HBO) treatment in MEO, our own experience and others' experience in applying this treatment method. We treated eight patients with MEO applying pharmacotherapy, topical management, surgery in one case and also adjunct HBO. In six patients, infection was caused by Pseudomonas aeruginosa, in one by Staphylococcus sp. and in one by Aspergillus sp. Complete recovery was achieved in seven patients. In the patient with MEO caused by Aspergillus sp., intracranial complications developed and the patient died. Our experiences in employing HBO in bacterial-caused MEO have confirmed the role of HBO as a valuable, beneficial, supporting classical treatment method. Small number of patients with MEO, especially with non-bacterial infection, and unforeseen clinical course of disease make our experience difficult to objectivize.

Value of hyperbaric oxygen in bacterial and fungal malignant external otitis treatment

Background and purpose We have investigated the treatment results of hyperbaric oxygen (HBO2) to patients with radiation-induced tissue complications. Material and methods Eight patients (1.4%) from 548 with head and neck cancers treated surgically with post- or preoperative radiotherapy or radiotherapy alone in standard doses who developed postradiation complications (6 patients with laryngeal chondroradionecrosis, 1 patient with osteoradionecrosis of the temporal bone, and 1 patient with soft tissue radionecrosis) are presented. To evaluate radiation reactions occuring in the head and neck region, we used the Chandler grading system for classification of postradiation larynx injuries and SOMA/LENT score for classification of postradiation injuries of mucosa of upper aerodigestive tract. Grades I and II in those grading systems are expected side effects of radiation therapy, thus our cases were all in grades III and IV. The HBO2 was performed after failure of the conventional treatment (antibiotics, steroids, topical therapy). The number of HBO2 expositions was from 8 to 39 and the delay to therapy from 2 to 22 months. Results Symptoms resolved in all treated patients. Six patients with laryngeal chondroradionecrosis had no symptoms after therapy and in three of them after partial laryngectomy the decannulation was performed. In one patient with mucosal radionecrosis after total laryngectomy, the esophageal fistula was closed and in one patient with osteoradionecrosis of the temporal bone, wound debridement followed. Conclusion The authors' experience supports the increasing clinical evidence that HBO2 is an effective adjunct therapy for treatment of complications of irradiation in head and neck area.

Hyperbaric oxygen therapy in the treatment of complications of irradiation in head and neck area.

Conclusion: By means of three-dimensional display of the critical measurements, the authors suggest a novel definition of ‘dangerous ethmoid’. Parallel to Keros type III, the proposed determining factors include: olfactory fossa width >6 mm, its distance to the medial nasal concha (turbinate) <20 mm and to the orbit interval of <10 mm. Clinical evaluation of these preliminary criteria based only on radiological data is required and underway.Objectives: Detailed pre-operative assessment of sinus computer tomography (CT) scans reduces the frequency of severe complications in patients undergoing endoscopic sinus surgery (ESS). The authors aimed to identify a sub-set of anatomical features pre-disposing to major post-operative complications.Method: Sinus computer tomography (CT) scans of patients of a single institution qualified for ESS were examined. Besides the Keros classification, authors focused on the anatomic measurements as follows: the olfactory fossa depth, width, and its distance from the ...

Is the Keros classification alone enough to identify patients with the ‘dangerous ethmoid’? An anatomical study

Nasal mucociliary transport was measured in a group of 30 adult patients (eight women and 22 men; age range 21-78 years, mean 47.9 years) treated with hyperbaric oxygen (HBO) therapy and in a control group of 32 adult subjects (two women and 30 men; age range 20-50 years, mean 32.0 years) compressed in a hyperbaric chamber without oxygen therapy. The treated patients breathed 100% oxygen at 250 kPa pressure for 60 min. Subjects from the control group were compressed in the hyperbaric chamber at 250 kPa for 70 min. Nasal mucociliary transport was measured with the saccharin clearance test. After exposure to HBO, the nasal mucociliary transport time was significantly decreased by 26% (P < 0.01) and returned to the original value after 24 h (increased by 8.3%, P = 0.25). In the control group, compressed in air, there were no statistically significant changes. This study shows that simultaneous compression and pure oxygen cause an increase in nasal mucociliary transport. The mechanism of activation of mucociliary clearance is probably the increased oxygenation of blood plasma and enhancement of metabolism in ciliated epithelium.

Tomasz Przewozny

Papers

Usefulness of high doses of glucocorticoids and hyperbaric oxygen therapy in sudden sensorineural hearing loss treatment.

Value of hyperbaric oxygen in bacterial and fungal malignant external otitis treatment

Hyperbaric oxygen therapy in the treatment of complications of irradiation in head and neck area.

Is the Keros classification alone enough to identify patients with the ‘dangerous ethmoid’? An anatomical study

The effect of hyperbaric oxygen on nasal mucociliary transport.