Clinical and animal experiment studies to optimise the therapy for acute acoustic trauma.

Despite extensive educational measures and improved ear protection, acute acoustic trauma still represents a major problem for the young soldier in the Federal Armed Forces. The aim of the investigation was thus to establish the optimum therapeutic scheme that could be applied by the generally young and still inexperienced unit medical officer to patients who had suffered acute acoustic trauma and to demonstrate the therapeutic scheme in animal experiments. In the clinical section, ten studies conducted on 500 patients who had suffered acute acoustic trauma made it possible to show that the combination of low-molecular dextran, or low-molecular hydroxyethyl starch, and hyperbaric oxygenation produced the best therapeutic results in terms of hearing gain and tinnitus elimination by a statistically significant margin. The studies only included patients who showed no tendency towards spontaneous recovery, with strict exclusion criteria being applied. Through animal experiments, it was seen that hyperbaric oxygenation, in the manner in which we conducted it (100% oxygen at 2.5 bar), leads to an increase in the oxygen partial pressure in the perilymph of the guinea pig cochlea. This is due partly to diffusion and partly to the blood flow. In a further experimental approach using animals, it proved possible to show that 60 hours after damage by acoustic trauma and hyperbaric oxygenation, the number of inner ear sensory cells that had suffered morphological damage in the animal was lower than without the hyperbaric oxygenation by a statistically significant margin. At the same time, valuable information was gained on the epidemiology of acute acoustic trauma.

[A method for relieving tinnitus complaints in long-enlisted soldiers with multiple acoustic traumas--external electrostimulation]. / Eine Methode zur Linderung von Tinnitusbeschwerden bei längerdienenden Soldaten mit multiplen Knalltraumen--Die externe Elektrostimulation.

The effect of external electrostimulation (EES) on tinnitus in soldiers with multiple blast trauma was assessed in a controlled study. There was no change in the tinnitus in the untreated control group during an observing period of 5 weeks. However the noise resolved completely within 28 days of therapy in 20% of treated soldiers, in some patients the symptoms were improved. The repeated application of EES is effective in recurrent complaints. This method can be carried out on an out-patient basis and scarcely has any side-effects. It is not suitable for treating tinnitus after acute acoustic trauma.

[Hyperbaric oxygenation--a sensible adjunctive therapy in malignant external otitis]. / Hyperbare Oxygenation--eine sinnvolle Zusatztherapie bei Otitis Externa Maligna.

This study shows the effect of hyperbaric oxygenation as an adjunctive therapy in malignant external otitis on the basis of three cases: one stage I, one stage II, two stages III (according to Ganz). Due to the successes achieved, and basing on a comparative study of the literature, we can conclude, even without a control group, that hyperbaric oxygenation exercises a positive influence on the reduction of Pseudomonas aeruginosa in the external auditory canal, and on the symptoms of pain and regeneration of cerebral nerves injured with a broad-spectrum allergy to antibiotics, even the exclusive application of the hyperbaric oxygenation proved successful.

[Hyperbaric oxygen therapy in sudden deafness]. / Zur hyperbaren Sauerstofftherapie beim Hörsturz.

Based on two independent studies, an attempt is made in this paper to demonstrate the effect of hyperbaric oxygen therapy used as a supportive measure to accompany standard treatment in recent acute loss of hearing and in acute loss of hearing where preoperative treatment has proved unsatisfactory. Whereas hyperbaric oxygen therapy is superior to the standard treatment alone as far as the cochlear perception dysacousis and tinnitus in recent acute loss of hearing are concerned, these results could not be reproduced in existing, preoperatively treated acute loss of hearing. As such, hyperbaric oxygen therapy under the strict supervision of a specialist physician has proved an effective supportive measure in the treatment of recent acute loss of hearing.

[Hyperbaric oxygen therapy of anaerobic brain abscesses following tonsillectomy]. / Die hyperbare Sauerstofftherapie bei anaeroben Hirnabszessen nach Tonsillektomie.

This study describes the clinical course of a 31 year old woman who developed multiple anaerobic brain abscesses six days after tonsillectomy, followed by hemoparesis and dysarthria. In spite of craniotomy, repeated punctures and drainage of pus and high dose local and systemic antibiotics, there was an obvious deterioration in the patient's condition. Hyperbaric oxygen therapy was tried as a last resort. The patient improved quickly, and six months after the tonsillectomy seems to be neurologically symptomfree.

Hyperbaric oxygen therapy for acute acoustic trauma.

We conducted a study on the effect of hyperbaric oxygen therapy on 122 soldiers following acute acoustic trauma. The patients included in this study, after the effect of spontaneous recovery had largely been excluded, were randomly allocated to four treatment groups. The results of our studies show that hyperbaric oxygen therapy shortens the course of healing with respect to high-pitch perception dysacusis. The results of treatment after an observation period of 6 weeks is also more favorable when patients are treated with oxygen when compared to patients given infusions or vasoactive substances. Similarly, the use of hyperbaric oxygen therapy also reduces the frequency of relapse following discharge from hospital. In contrast, the vasoactive substance chosen in our studies (betahistine) failed to have a favorable effect on the course of healing. Our study has also shown that no method can compare with hyperbaric therapy in eliminating tinnitus following acoustic trauma.