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R Hamann

Publications and source records attributed to R Hamann.

4 recordsLinked to original sources

[Experiences with the psychometric system combitest in the evaluation of the postnarcotic arousal period].

Since the introduction of new German health legislation, operations formerly performed on an in-patient basis have been transferred to the out-patient sector. Due to this development evaluating the postnarcotic arousal period has become increasingly important. Vigilance, reactivity and state of health determine a patient's well-being and time of discharge after an operation and consequently influence economical and legal issues. Former studies investigating the arousal period have mainly focused on patient interviews and assessment of patients by staff. The aim of our study was to objectivize postnarcotic vigilance and reactivity (critical flicker fusion frequency and multiple choice reaction) using neurophysiological monitoring (psychometric system Combitest 2: CFF, EWR, MWR). The applied methods have been defined as valid, reliable and sensitive tools to investigate this question. Inter-individual and gender-specific differences as well as variations due to the type of anaesthetic employed can be detected. The study participants assessed the test battery's practicability and overall described this method as easy to use. Vigilance (CFF), basic and complex sensomotor reactivity (performance in simple and multiple choice tests) were restored after a postanaesthetic phase of 90 minutes (narcotics applied: isofluran and propofol). The results show that the use of modern anaesthetics does not justify the current medical and legal claim to 6 hours of postanaesthetic observation. The computer-supported psychometric system Combitest 2 has recently been used to assess the arousal phase after application of different types of anaesthetical procedures (TIVA, volatile, balanced) and has been found to be superior to parameters traditionally used to assess discharge criteria (time until patient opens eyes, orientation concerning time and location, time spent in postanaesthetic recovery room). Besides employing our study methods, subjective factors such as well-being and pain sensation should also be evaluated when determining the time of a patient's discharge.

Analgesics, Opioid↗

Comparison of PCDD and PCDF concentrations after aerobic and anaerobic digestion of sewage sludge.

The anaerobic stabilization of raw sludges of different origin was investigated. Precursors like chlorophenol and chlorobenzene isomers were added to some of the samples. The change of the PCDD/F concentrations as well as the change in the pattern of the isomers and congeners was independent of the type and amount of the added precursor. With respect to the change of the PCDD/F concentrations the digestion properties were typical in each digestion series but not applicable to other digestion processes. The quality of the digestion was characterized by measuring the change of pH, controlling the biogas flow rate and the determination of the mineralization degree. The added chlorobenzenes and chlorophenols were almost completely degraded. The aerobic digestion occurred in ventilated batch reactors leading to a significant degradation of all PCDD/F homologues. The degradation ratio depends on the origin of the sewage sludge. Independent of origin individual congeners were partially or completely degraded.

Aerobiosis↗