[Hyperbaric oxygenation. An area for the anesthetist?]. / Hyperbare Oxygenation. Ein Betätigungsfeld für den Anästhesisten?

Hyperbaric Oxygen (HBO) therapy is a kind of medical treatment in which a patient breathes 100% of oxygen inside a pressure chamber while the pressure of the chamber is increased to a point higher than sea level pressure. It is strongly based on clearly defined physical laws and physiological regularities. For the clinical use of HBO therapy, according to international recommendations, there are several commonly accepted indications in which HBO either is the only causative life-saving kind of treatment, or is an essential and oftenly decisive component of a comprehensive interdisciplinary intensive care therapy. Among potential adverse effects, barotrauma of the lungs and especially oxygen toxicity to the central nervous system have to be mentioned. Clinical use of HBO therefore requires special knowledge of its effects, risks, and adverse effects, a clear and distinct indication, and the ability and skills to keep complications under control by means of intensive care or emergency medical measures. The clinical use of hyperbaric oxygen with its interdisciplinary-like character of emergency medicine or intensive care therapy therefore should be an additional, most interesting field of activity for the anaesthesiologist.

Detection of DNA damage after hyperbaric oxygen (HBO) therapy.

Hyperbaric oxygen (HBO) therapy is successfully used for the treatment of a variety of conditions. However, exposure to high concentrations of oxygen is known to induce damage to cells, possibly due to an increased oxygen radical production. As reactive oxygen species also cause DNA damage, we investigated the DNA-damaging effect of HBO with the alkaline version of the single cell gel test (comet assay). Oxidative DNA base modifications were determined by converting oxidized DNA bases to strand breaks using bacterial formamidopyrimidine-DNA glycosylase (FPG), a DNA repair enzyme, which specifically nicks DNA at sites of 8-oxo-guanines and formamidopyrimidines. HBO treatment under therapeutic conditions clearly and reproducibly induced DNA damage in leukocytes of all test subjects investigated. Increased DNA damage was found immediately at the end of the treatment, while 24 h later, no effect was found. Using FPG protein we detected significant oxidative base damage after HBO treatment. DNA damage was detected only after the first treatment and not after further treatments under the same conditions, indicating an increase in antioxidant defences. DNA damage did not occur when the HBO treatment was started with a reduced treatment time which was then increased stepwise.

[Bilateral Gradenigo syndrome--on the value of an integrated therapy concept including hyperbaric oxygenation and chronic destructive inflammation of the skull base]. / Gradenigo-Syndrom beidseits--Zum Stellenwert eines integrierten Therapiekonzepts unter Einschluss der hyperbaren Oxygenation bei chronisch-destruierenden Entzündungen der Schädelbasis.

The case of a 30-year-old female with bilateral Gradenigo's syndrome is presented in order to detail commonly applied therapy. In particular, the importance of a comprehensive therapeutic approach is emphasized that includes such adjuvant therapeutic options as hyperbaric oxygenation and the administration of specific immunoglobulins. Indications, therapeutic benefits and limitations of treatment modalities are discussed in relationship to current concepts of therapy.

[Principles of acute management of the severe diving accident]. / Grundlagen der Akutversorgung des schweren Tauchunfalles.

The basics of the acute management of severe diving accidents are outlined by means of 25 patients (20 patients presented with decompression sickness, 5 suffered from a barotrauma of the lungs with consecutive air embolism) treated at our facilities. Contrary to widespread notion, disturbed vital functions have to be treated by intensive care measures, prior to the definite recompression therapy. These are: (1) Treatment of generalized or localized tissue hypoxia secondary to bubble-generation; (2) puncture of a (valvular-) pneumothorax after a pulmonary barotrauma; (3) haemodynamic stabilization when cardiac or spinal shock is present; (4) improvement of the rheological situation. When vital functions are unstable or endangered, these patients must not be transported in a monoplace chamber. This type of chamber does not leave any access to the patient in case of a deteriorating status. Since the severe diving accident mostly turns out to be a problem of intensive care medicine in close combination with the recompression therapy, the continuous integration of the recompression protocol with a comprehensive intensive care therapy is considered crucial.

[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.

Liposomes as carriers of iodolipid radiocontrast agents for CT scanning of the liver.

We studied the potential of liposomes to deliver oil soluble radiocontrast agents to the liver and have developed a new preparation for CT liver scanning. The preparation consists of Ethiodol with a large amount of phospholipids. Nuclear magnetic resonance (NMR) spectroscopy was done for this lipid preparation, and the spectra show that the lipids are in the bilayer liposome configuration. Electron microscopy provides direct visualization of the liposomes. X-ray fluorescence measurements suggest that the Ethiodol is incorporated in the liposomes, and since no other particulate configurations are observed, we conclude that the Ethiodol is contained within the hydrophobic region of the liposomes. We used a GE CTT-8800 scanner and a rabbit model to study the liver uptake of the iodine from the Ethiodol. The iodine uptake in the liver was rapid and significant, and an increase in HU number of more than 40 was observed within 20 minutes after i.v. injection of 50 mg I/kg of body weight. Significant image enhancement was obtained. The iodine from the Ethiodol remained in the liver for several hours. Studies in rabbits with hepatic implants of the VX2-carcinoma show that while normal liver concentrates, areas of tumor do not concentrate the Ethiodol liposomes. Tumors not visible on ordinary scans become visible after administration of this combination. The advantages of this liposomal mode of radiocontrast agent administration are small particle size, rapid uptake in the liver, long retention times, a large increase in HU number and low iodine dose.

[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.