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W Meissner

Publications and source records attributed to W Meissner.

At least 19 recordsLinked to original sources
PubMed2006

[What is the value of pain therapy in the German refined diagnosis-related-groups system?].

The German refined diagnosis-related-groups (G-DRG) system was introduced on 1st January 2003, initially on a voluntary basis and on 1st January 2004 the use of a G-DRG costing for stationary hospital treatment became obligatory. The possibility of a description of acute and chronic pain therapy in the G-DRG system was initially rudimentary and not logically planned and also a fair allotment of proceeds according to resources was not possible. By further development of the G-DRG system, pain therapeutic treatment could be improved in some areas, but in others it still remains unsatisfactory. This article offers a summary of the underlying systematics of the G-DRG system and consideration of chronic and current pain therapy in the G-DRG system 2006. In addition to information on currently available possibilities of a pain therapeutical coding in conformation with the G-DRG system, the tasks which are still outstanding will be outlined.

Acute Disease↗
PubMed2006

Benchmarking as a tool of continuous quality improvement in postoperative pain management.

BACKGROUND AND OBJECTIVE: Quality of acute pain management is far from being satisfactory. These deficits are not caused by the complexity of the medical problem but by difficulties in organization and hospital structures, sand procedures. Continuous quality improvement is a recommended tool to overcome such difficulties and to increase quality in the long run. This study reports the implementation of benchmarking-based continuous quality improvement to improve postoperative pain management at a university hospital. METHODS: A specialised pain nurse interviewed patients of three surgical departments on the first day after surgery, and continuously assessed process and outcome quality parameters. A multidisciplinary team of anaesthetists, surgeons, nurses and pharmacists implemented a regular procedure of data analysing and internal benchmarking. Results and suggested improvements were fed back to the healthcare teams. RESULTS: From 1998 to 2002, 6,756 patients were assessed. Average pain on ambulation and maximal pain were 3.7 +/- 2.4 and 5.0 +/- 2.5 (mean +/- SD) on a 11-point numeric rating scale. Pain intensity at rest was 1.9 +/- 1.8. Over time, pain intensity on ambulation decreased (P = 0.022) whereas maximal pain and pain at rest remained unchanged. There was an increase in the number of patients who received non-opioid analgesia (P < 0.001). CONCLUSIONS: A continuous quality improvement process could be established and is now successfully used in clinical routine. Cornerstones of this project were frequent assessments of process and outcome parameters, regular benchmarking and implementation of feedback mechanisms. Changes in organization of medical management and multidisciplinary teamwork seem to be more important than medical or technical aspects.

Abdomen↗
PubMed2005

Coherent spike-wave oscillations in the cortex and subthalamic nucleus of the freely moving rat.

The basal ganglia play a critical role in controlling seizures in animal models of idiopathic non-convulsive (absence) epilepsy. Inappropriate output from the substantia nigra pars reticulata (SNr) is known to exacerbate seizures, but the precise neuronal mechanisms underlying abnormal activity in SNr remain unclear. To test the hypothesis that cortical spike-wave oscillations, often considered indicative of absence seizures, propagate to the subthalamic nucleus, an important afferent of SNr, we simultaneously recorded local field potentials from the frontal cortex and subthalamic nucleus of freely moving rats. Spontaneous spike-wave oscillations in cortex (mean dominant frequency of 7.4 Hz) were associated with similar oscillations in the subthalamic nucleus (mean of 7.9 Hz). The power of oscillations at 5-9 Hz was significantly higher during spike-wave activity as compared with rest periods without this activity. Importantly, spike-wave oscillations in cortex and subthalamic nucleus were significantly coherent across a range of frequencies (3-40 Hz), and the dominant (7-8 Hz) oscillatory activity in the subthalamic nucleus typically followed that in cortex with a small time lag (mean of 2.7 ms). In conclusion, these data suggest that ensembles of subthalamic nucleus neurons are rapidly recruited into oscillations during cortical spike-wave activity, thus adding further weight to the importance of the subthalamic nucleus in absence epilepsy. An increase in synchronous oscillatory input from the subthalamic nucleus could thus partly underlie the expression of pathological activity in SNr that could, in turn, aggravate seizures. Finally, these findings also reiterate the importance of oscillations in these circuits in normal behaviour.

Action Potentials↗
PubMed2004

[Effect of enteral naloxone on the incidence of gastritis and esophagitis in mechanically ventilated patients].

BACKGROUND: Gastrtis and esophagitis are frequent and severe complications in intensive care patients, mainly caused by increased duodenogastral reflux. Opioids, commonly used in intensive care, are known to impair gastrointestinal (GI) motility which increases retrograd flow of gastric content. In a previous study, we showed that enteral administered naloxone reduces gastric reflux by selectively blocking GI opioid receptors. Therefore, in a subpopulation of these patients we studied the effect of enteral naloxone on the incidence of mucosal injury in opioid-treated, mechanically ventilated patients. METHODS: After IRB approval, mechanically ventilated, fentanyl-treated patients without gastrointestinal surgery or diseases were assigned to receive 8 mg naloxone or placebo four times daily via a gastric tube. Additional inclusion criteria were opioid treatment for at least three days and endoscopy of the upper GI tract. Frequency of gastritis and esophagitis was quantified according to the Savary-Miller Score, and further parameter of GI motility (frequency of propulsive medication, amount of enteral feeding) were measured. RESULTS: In four of seventeen patients of the naloxone group (24 %) and 14 of 22 patients of the placebo group (64 %; p = 0.02), esophageal or gastral mucosal injuries were detected. In the naloxone group, gastral reflux as well as need for propulsive medication were significantly lower. Volume of enteral feeding showed an increasing trend in the second half of the study. CONCLUSION: Reduction of esophagogastral mucosal injury and reduced need for procinetic medication suggests an improvement of GI motility by enteral naloxone in fentanyl-treated, mechanically ventilated patients.

Adult↗
PubMed2004

Effects of N-, P/Q- and L-type calcium channel blockers on nociceptive neurones of the trigeminal nucleus with input from the dura.

In anaesthetized rats, extracellular recordings were made from neurones of the spinal trigeminal nucleus, involved in the processing of nociceptive input from the dura. Blockers of voltage-gated calcium channels (VGCCs) were administered topically to the exposed brainstem. Blockade of N-type (CaV2.2) channels reduced spontaneous activity and responses of the neurones to cold and chemical stimuli applied to the dura, suggesting that N-type channels regulate excitatory synaptic activation. Blockade of L-type (CaV1) channels enhanced spontaneous discharges of the neurones. Blockade of P/Q-type (CaV2.1) channels slightly decreased responses to chemical and cold stimuli but markedly increased spontaneous activity, an effect which was absent during concomitant application of GABA to the brainstem. The data suggest that P/Q-type VGCCs regulate a tonic synaptic inhibitory control of the brainstem neurones. The risk of migraine by genetic modifications of P/Q-type channels may thus be sought in disturbed inhibition in the network that processes nociceptive dura input.

Action Potentials↗
PubMed2003

The effects of frequency in pallidal deep brain stimulation for primary dystonia.

The effect of stimulation frequency for pallidal deep brain stimulation in five patients with either generalized or segmental dystonia was evaluated three to twelve months postoperatively via a randomized, double-blind paradigm. The quality of life and the severity of dystonic symptoms improved by approximately 60% and 43% respectively using a frequency of 130 Hz. Compared with 130 Hz a significant further clinical improvement was observed at frequencies of 180 and 250 Hz, which contrasted with a significant deterioration at lower frequencies (5, 50 Hz) compared to 130 Hz.

Adolescent↗
PubMed2002

[The use of the infraclavicular plexus catheter for treatment of perioperative and chronic pain].

OBJECTIVES: The aim of this prospective study was to evaluate the vertical infraclavicular approach to the brachial plexus for the insertion of a catheter to achieve continuous analgesia in postoperative patients and patients with chronic upper limb pain. METHODS: The brachial plexus was identified using the technique described by Kilka et al. and a flexible catheter (diameter 0.85 mm) was introduced 3-5 cm into the perineural sheath via the punction cannula. Regional analgesia was achieved by intermittent injection of local anaesthetic agent. Placement of the catheter, duration and effectiveness of treatment, complications and reasons for catheter removal were recorded using a standard protocol. RESULTS: A total number of 226 plexus catheters were placed in 210 patients. Consecutive regional analgesia for at least 48 h was possible in 88%. Analgesia was sufficient in 76% of patients up to the time of catheter removal. The median (minimum-maximum) duration of catheterisation in the whole collective was 7 days (1-240) and 11 days in patients with chronic pain. Almost 30% of the patients were treated for 10 days or longer and 4.4% were treated for 1 month or longer. Major complications occurred in only three cases, while technical problems and minor complications (redness at puncture site) occurred in 10% of cases. CONCLUSIONS: The placement of an infraclavicular plexus catheter is a suitable method for pain management in the upper limb. This approach may have advantages in patients with severe injuries who cannot abduct the arm. Our results are encouraging in terms of catheterisation time, patient comfort and incidence of complications.

Anesthetics, Local↗
PubMed2001

Striatal dopaminergic metabolism is increased by deep brain stimulation of the subthalamic nucleus in 6-hydroxydopamine lesioned rats.

Deep brain stimulation of the subthalamic nucleus is an established therapeutic strategy for patients with Parkinson's disease. Although the exact mechanisms of action remain unknown, it is noteworthy that dopaminergic medication can be markedly reduced after neurostimulation of the subthalamic nucleus. Previously, we have shown that deep brain stimulation of the subthalamic nucleus is followed by an increase of striatal extracellular dopamine metabolites in naive rats. In the present study we examined the effects of deep brain stimulation on striatal monoamine metabolism in the intrastriatal 6-hydroxydopamine rat model of Parkinson's disease. Deep brain stimulation of the subthalamic nucleus was followed by a delayed increase of extracellular 3,4-dihydroxyphenylacetic and homovanillic whereas dopamine levels were unchanged in stimulated rats and controls. Our results indicate that deep brain stimulation of the subthalamic nucleus affects significantly striatal dopaminergic metabolism in 6-hydroxydopamine lesioned rats.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2001

Development of an inducible pol III transcription system essentially requiring a mutated form of the TATA-binding protein.

We attempted to devise a transcription system in which a particular DNA sequence of interest could be inducibly expressed under the control of a modified polymerase III (pol III) promoter. Its activation requires a mutated transcription factor not contained endogenously in human cells. We constructed such a promoter by fusing elements of the beta-lactamase gene of Escherichia coli, containing a modified TATA-box and a pol III terminator, to the initiation region of the human U6 gene. This construct functionally resembles a 5'-regulated pol III gene and its transcribed segment can be exchanged for an arbitrary sequence. Its transcription in vitro by pol III requires the same factors as the U6 gene with the major exception that the modified TATA-box of this construct only interacts with a TATA-binding protein (TBP) mutant (TBP-DR2) but not with TBP wild-type (TBPwt). Its transcription therefore requires TBP-DR2 exclusively instead of TBPWT: In order to render the system inducible, we fused the gene coding for TBP-DR2 to a tetracycline control element and stably transfected this new construct into HeLa cells. Induction of such a stable and viable clone with tetracycline resulted in the expression of functional TBP-DR2. This system may conceptually be used in the future to inducibly express an arbitrary DNA sequence in vivo under the control of the above mentioned promoter.

Base Sequence↗
PubMed2001

Neurostimulation of the ventral intermediate thalamic nucleus in inherited myoclonus-dystonia syndrome.

We report on the effects of bilateral neurostimulation of the ventral intermediate thalamic nucleus (VIM) in a patient with medically intractable and progressing inherited myoclonus dystonia syndrome (IMDS). Postoperatively, the patient improved by approximately 80% on the modified version of a myoclonus score without any significant change in the dystonic symptoms. This suggests that neurostimulation of the VIM may be an effective treatment for myoclonus in pharmacologically intractable IMDS.

Brain Mapping↗
PubMed2001

[Quality management in postoperative pain therapy].

BACKGROUND: Deficits in quality of postoperative pain management are not caused by the complexity of the medical problem or shortage of suitable drugs but by difficulties in organization and hospital structures. Moreover, there is no consensus on how to measure the quality of pain management. Quality management programs consist of strategies to overcome such difficulties and to increase quality continuously. This study reports the implementation of a quality management program to improve postoperative pain management at a university hospital. METHODS: An interdisciplinary task force consisting of nursing staff, anesthesiologists, surgeons, and members of the hospital pharmacy was set up. This task force interviewed patients and performed an analysis of current deficits (phase 1). Then, primary and secondary outcome parameters were defined to measure quality of pain management, and strategies were defined to implement improvements (phase 2). These referred to aspects of organization, standardization, and responsibility. One of the main intentions was the involvement of nursing staff. After implementation (phase 3), a second analysis was performed (phase 4). This was followed by a continuous assessment of parameters indicating quality of procedures and results which were fed back to all participants (phase 5). RESULTS: After implementation of the program (phase 4), significantly more patients reported no or mild (NRS < 4) postoperative pain (40.2% vs 30.1%) compared to phase 1. Also, patients' satisfaction with pain therapy improved significantly. The proportion of patients without pain treatment decreased by one-third. Opioids were given more frequently and more often intravenously. In contrast, the proportion of i.m. injections decreased from 20% to 5%. Continuous assessment of up to now more than 4,900 patients helped to identify possible reasons for problems and to maintain overall quality of pain management. DISCUSSION: Tools of quality management consisting of deficit analysis, definition of outcome parameters, implementation of improving strategies, post-intervention analysis and continuous feed-back may be successfully used to improve postoperative pain therapy. Changes in organization of medical management seem to be more important than medical or technical aspects. Similar strategies might be used to increase quality of other medical procedures.

Analgesics, Opioid↗
PubMed2001

[Apomorphine therapy versus deep rain stimulation. Clinical and economic aspects in patients with advanced Parkinson disease].

Long-term dopaminergic treatment of Parkinson's disease is complicated by the occurrence of dyskinesia and motor fluctuations and is responsible for increasing the costs of treatment. In these patients, continuous subcutaneous therapy with the dopamine agonist apomorphine or deep-brain stimulation represents a promising strategy. While the costs for the treatment with apomorphine are covered by health insurance, separate reimbursement for deep-brain stimulation does not exist in Germany. The case reports (n = 3) presented here emphasize that deep-brain stimulation is less cost-intensive than subcutaneous treatment with apomorphine in selected patients. Even in the first postoperative year costs for medication and hospital stays were reduced by approximately 60%. Moreover, in all three patients, motor complications improved after deep-brain stimulation in comparison to previous subcutaneous application of apomorphine. Thus, to further ensure deep-brain stimulation in parkinsonian patients it is mandatory to find a mode of reimbursement for the institutions concerned.

Aged↗
PubMed2001

Pallidal and thalamic neurostimulation in severe tardive dystonia.

A 70 year old woman presented with a 6 year history of medically refractory severe tardive dystonia. After informed consent, a bilateral stereotactic electrode placement targeting the ventral intermediate thalamic nucleus (VIM) and the globus pallidus internus (GPi) was performed. After bilateral stimulation of the GPi, the patient showed a clear and stable improvement of the painful dystonic syndrome within hours. Stimulation of the VIM did not improve the hyperkinetic movements and simultaneous stimulation of both the GPi and the VIM did not result in any additional benefit. The possible pathophysiological mechanisms are discussed.

Aged↗
PubMed2000

The influence of pallidal deep brain stimulation on striatal dopaminergic metabolism in the rat.

Deep brain stimulation of the globus pallidus internus has been recently shown to alleviate parkinsonian symptoms and levodopa-induced dyskinesias. However, its exact mechanisms of action are unclear. Pallidal neurones are connected via various pathways to the dopaminergic nigrostriatal system. In the present study we investigated the hypothesis that deep brain stimulation of the entopeduncular nucleus (corresponds to the human internal pallidum) affects striatal dopaminergic metabolism in naive and 6-hydroxydopamine (6-OHDA) lesioned rats using microdialysis. Our results show that stimulation of the entopeduncular nucleus does not significantly affect striatal dopamine metabolism (of dopamine, 3, 4-dihdroxyphenylacetic acid and homovanillic acid) in naive and 6-OHDA-lesioned animals. They contrast with our previous observations that deep brain stimulation of the subthalamic nucleus increases striatal dopamine metabolism suggesting differential effects of these nuclei on striatal dopamine metabolism.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2000

Transcription efficiency of human polymerase III genes in vitro does not depend on the RNP-forming autoantigen La.

Transcription of class III genes is conducted by multi-protein complexes consisting of polymerase III itself and several transcription factors. We established a reconstituted in vitro transcription system from which the autoantigen La was removed by immunodepletion. This system showed no RNP formation, but was still fully active in transcription. Supplementing such La-free transcription reactions with recombinant La restored the formation of La complexes with the newly synthesised RNA, but did not lead to enhanced transcription efficiency. Furthermore, we developed a technique for the generation and isolation of transcription complexes, assembled from purified transcription factors and isolated by glycerol centrifugation. These complexes were fully competent to re-initiate RNA synthesis but they were not associated with La and their transcription rate could not be stimulated by addition of recombinant La. Therefore, we conclude that La does not act as a human polymerase III transcription factor.

Antibodies↗
PubMed2000

High frequency stimulation of the subthalamic nucleus influences striatal dopaminergic metabolism in the naive rat.

High frequency stimulation (HFS) of the subthalamic nucleus (STN) can partially alleviate motor symptoms in patients with Parkinson's disease (PD). However, the mechanism of action of HFS is incompletely understood. We investigated the effect of HFS (130 Hz) and low frequency stimulation (LFS, 20 Hz) of the STN on striatal dopaminergic transmission and metabolism using in vivo microdialysis in anaesthetized and freely moving rats. While LFS had no effect, HFS of the STN produced a delayed, stable and intensity-dependent increase of extracellular dopamine metabolites. Striatal extracellular levels of dopamine and 5-HIAA were not influenced by HFS or LFS in the present experimental paradigm. We conclude that HFS of the STN influences striatal dopaminergic metabolism in naive, nonlesioned rats.

3,4-Dihydroxyphenylacetic Acid↗