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Biomedical subjects

A Bickel

Publications and source records attributed to A Bickel.

At least 19 recordsLinked to original sources

[An expert system neurology--possibilities and limitations].

We present an expert system Neurology, which was developed completely on basis of the commercial available data base program Filemaker-7.0. At present it covers approximately 400 diagnoses of neurological and psychiatric diseases. After the input of cardinal symptoms, course and localisation of the disease the program calculates a first set of possible differential diagnoses and asks for additional symptoms or the performance of apparative diagnostics to investigate the final diagnose. At first, the performance of the expert system was tested with 15 predetermined neurological case reports. Users with different previous knowledge of Neurology performed the input. In this test the program was able to identify the correct diagnose in nearly all cases and the diagnostic proposals were superior to those of the users with minor neurological training. In a second test with real patient data, the rate of correct diagnoses was approximately 80%. In summary, the used computer algorithms proved as appropriate for the aim of giving Neurological diagnoses. Possible additional applications could be student training or the use as interdisciplinary reference work.

Algorithms↗

Follow-up of advanced diabetic neuropathy: useful variables and possible pitfalls.

BACKGROUND: The course of advanced diabetic neuropathy (DN) is largely unknown. AIM: To find variables allowing the follow-up of late stages of DN. METHODS: Thirty diabetic patients with DN were observed. Patients were examined at intervals of 6 months over a period of 2 years. The compound muscle action potentials (CMAPs) were recorded in extensor digitorum brevis (EDB) and flexor hallucis brevis (FHB) muscles. Clinical severity of DN, nerve conduction studies (NCS), quantitative sensory testing (QST) and heart rate variability (HRV) were evaluated. The data were compared with age- and sex-matched controls. RESULTS: All measures were sensitive to the detection of DN. Significant deterioration during follow-up was exclusively found in CMAP analysis of the EDB (p<0.05) and FHB muscles (p<0.03). NCS, QST and HRV remained unchanged within the 2 years of observation. Coincidental changes might occur, if only two time points are chosen for followup. CONCLUSION: Our results indicate that ongoing axonopathy predominates in advanced DN. Repeated testing helps to minimize the impact of coincidental or chance changes in DN follow-up studies.

Action Potentials↗

Exacerbation of migraine attacks during treatment with the selective serotonin reuptake inhibitor sertraline. A case report.

Abnormal signal transmission in central serotonergic pathways is supposed to play an important role in the pathogenesis of migraine and major depression. We report on a patient, who was treated during an episode of depression with the selective serotonin reuptake inhibitor (SSRI) sertraline and developed frequent migraine attacks under this therapeutical regime. Single migraine attacks were treated successfully with triptanes. Although SSRIs may be beneficial for migraine prophylaxis at long term administration, this case suggests that acute administration of SSRIs in migraineurs may include the risk of worsening migraine.

Adrenergic beta-Antagonists↗

Power spectral analysis of heart rate variability during helium pneumoperitoneum: The mechanism of increased cardiac sympathetic activity and its clinical significance.

BACKGROUND: Carbon dioxide pneumoperitoneum (PP) is known to induce increased cardiac sympathetic expression. The role of the insufflated gas involved in this mechanism should be elucidated in an attempt to eliminate its possible serious consequences. METHODS: Twenty-five patients undergoing elective laparoscopic cholecystectomy were prospectively analyzed for cardiac autonomic nervous activity by spectral heart rate variability. In 15 patients, helium was used as CO(2) substitution for abdominal insufflation (study group). Four frequency bands of interest were obtained from the power spectrum of R-R intervals, as well as the ratio between the low and high frequency (LF/HF), using the fast Fourier transformation algorithm to characterize the synergy of both autonomic branches during PP. RESULTS: Significantly increased values of the power spectrum related to the LF and VLF bands (from 130 to 377 msec(2)/Hz and from 145 to 516 msec(2)/Hz, respectively) were inspected during CO(2) PP, as well as increased LF/LH ratio (2.1). Using helium as CO(2) substitution has eliminated the significant changes in the power spectrum that reflect increased cardiac sympathetic activity. CONCLUSIONS: The elimination of sympathetic predominance by helium PP indicates the central role of CO(2) in establishing this phenomena. Considering this information and its other known advantages, helium should be considered for use during prolonged laparoscopic procedures for high-risk patients.

Adult↗

Sudomotor function in familial dysautonomia.

BACKGROUND: Patients with familial dysautonomia (FD) manifest episodic hyperhidrosis despite the reduction of sudomotor fibres and sweat glands associated with this autonomic neuropathy. We assessed peripheral sudomotor nerve fibre and sweat gland function to determine if this symptom was due to peripheral denervation hypersensitivity. METHODS: In 14 FD patients and 11 healthy controls, direct and axon reflex mediated sweat responses were determined by measuring transepidermal water loss (TEWL) after application of acetylcholine via a microdialysis membrane, a novel method to evaluate sudomotor function in neuropathy patients. Results were compared with data from conventional quantitative sudomotor axon reflex testing (QSART). Using microdialysis, interstitial fluid was analysed for plasma proteins to evaluate protein extravasation induced by acetylcholine as an additional parameter of C-fibre function. RESULTS: Although reduced axon reflex sweating was expected in FD patients, neither direct or axon reflex mediated sweat responses, nor acetylcholine induced protein extravasation differed between control and patient groups. However, the baseline resting sweat rate was higher in FD patients than controls (p<0.05). TEWL and QSART test results correlated (r = 0.64, p = 0.01), proving the reliability of TEWL methodology in evaluating sudomotor function. CONCLUSION: The finding of normal direct and axon reflex mediated sweat output in FD patients supports our hypothesis that, in a disorder with severe sympathetic nerve fibre reduction, sudomotor fibres, but not the sweat gland itself, exhibit chemical hypersensitivity. This might explain excessive episodic hyperhidrosis in situations with increased central sympathetic outflow.

Acetylcholine↗

Assessment of the neurogenic flare reaction in small-fiber neuropathies.

To improve sensitivity of the analysis of axon reflex flare reaction, the authors used a laser Doppler scanner and analyzed flare intensity and size induced by histamine iontophoresis simultaneously at the foot and thigh in patients with small-fiber neuropathy (n = 10) and controls (n = 9). Flare size, but not laser Doppler flux, clearly distinguished patients from controls at both locations (p < 0.01) and may be useful for evaluation of small-fiber neuropathies.

Aged↗

Power spectral analysis of heart rate variability during positive pressure pneumoperitoneum: the significance of increased cardiac sympathetic expression.

BACKGROUND: Positive pressure pneumoperitoneum (PPP) effects on the autonomic nervous system (ANS) might be of clinical importance, as imbalance in the autonomic cardiac control might lead to serious consequences. METHODS: Fifteen healthy patients undergoing elective laparoscopic cholecystectomy were analyzed for cardiac autonomic nervous activity by spectral heart rate variability, during awake state, before and after intubation, during CO2 PPP (14 mmHg), and after CO2 evacuation. The very low, low, high and very high frequency (VLF, LF, HF, VHF respectively) bands of the spectral density of the heart rate variability (HRV) and their normalized values, as well as the LF/HF ratio, were obtained from the power spectra of R-R intervals, using the fast-Fourier transformation algorithm. RESULTS: Using Friedman's nonparametric test, only the difference between the power of LF during anesthesia (median 30.74) and the middle of PPP (median 195.66) was found to be significant (p<0.012). Such change was recorded in 14 patients (p = 0.001, sign test). CONCLUSIONS: Increased LF power reflects sympathetic cardiac activation. As the LF range accounts for regulation of blood pressure and baroreflex, several mechanisms may explain this activation. This in turn may predispose patients who suffer from cardiac disease to higher risk of developing ventricular arrhythmias, besides the possible adverse hemodynamic consequences of PPP.

Adult↗

Dermal microdialysis provides evidence for hypersensitivity to noradrenaline in patients with familial dysautonomia.

OBJECTIVES: To use the technique of dermal microdialysis to examine sensitivity of skin vessels to noradrenaline (NA) in patients with familial dysautonomia (FD) and in healthy controls. METHODS: In 14 patients with FD and 12 healthy controls, plasma extravasation, local laser Doppler blood flow, and skin blanching were observed before, during, and after application of 10(-6) M NA through a microdialysis membrane, located intradermally in the skin of the lower leg. RESULTS: Maximum local vasoconstriction measured by laser Doppler blood flow did not differ between patients with FD and controls. In contrast, patients with FD had an earlier onset of vasoconstriction (p = 0.02). Moreover, reaction to NA was more prominent and prolonged in FD, shown by a larger zone of skin blanching around the microdialysis membrane (p < 0.001) and delayed reduction of the protein content in the dialysate after termination of NA application (p = 0.03). CONCLUSION: These data support the hypothesis that peripheral blood vessels of patients with FD show a denervation hypersensitivity to catecholamines. This may be one mechanism contributing to the major hypertension that frequently occurs during "dysautonomic crises" in FD.

Administration, Cutaneous↗

The laparoscopic approach to abdominal hydatid cysts: a prospective nonselective study using the isolated hypobaric technique.

HYPOTHESIS: The laparoscopic isolated hypobaric technique that we developed and use is safe and feasible for almost all kinds of hepatic and extrahepatic abdominal hydatid cysts. DESIGN: A case series. PATIENTS: Between August 1992 and December 1999, 31 patients with no selection criteria underwent 32 consecutive laparoscopic operations for 52 symptomatic hydatid cysts located in the liver (49), spleen (1), and pelvis (2). Eleven patients underwent surgery for between 2 to 5 cysts. INTERVENTIONS: The main surgical maneuvers (puncture, parasite neutralization, and complete evacuation) were performed through an assembled transparent cannula, in which a vacuum was created, while its tip adhered firmly to the cyst wall. Following evacuation of the cyst contents, we attempted to perform partial pericystectomy, omentoplasty, and closed-suction drainage. MAIN OUTCOME MEASURES: Surgical complications and postoperative disease recurrence. RESULTS: Mean cyst diameter was 8.4 cm (range, 3.5-25 cm). Seven cysts were subdiaphragmatic, and 6 were on the posterior (hidden) aspect of the liver. Mean postoperative follow-up was 49 months. Forty-one cysts contained live parasites, and 11 were secondarily infected. Twenty-four cysts were complex. Perioperative complications occurred in 5 patients, including 1 patient who died 1 month after surgery owing to Candida sepsis. Mean hospital stay was 6 days. No evidence of recurrence was recorded during follow-up. CONCLUSIONS: The isolated hypobaric laparoscopic technique described provides a safe and efficacious approach to almost all types of abdominal hydatid cysts and takes advantage of the recognized benefits of the laparoscopic approach.

Adolescent↗

[Effects of recommendations and patient seminars on effectivity of outpatient treatment for headache].

BACKGROUND: Treatment of patients suffering from migraine and/or tension-type headache in primary care needs to be improved. To this purpose we tested two strategies for implementation of evidence-based recommendations for treatment of headaches: first, communication of recommendations to the primary care physicians and, second, standardized communication and discussion of these recommendations with patients in combination with exercising of progressive muscle relaxation during patient seminars. METHODS: Patients with at least 2 migraine attacks/month or 8 days of tension-type headache/month were included in the study. Evidence-based pharmacological and non-pharmacological recommendations of the Medicines Committee of the German Medical Profession for treatment of migraine and tension-type headache have been offered to primary care physicians by printed material and during conferences. Patient seminars at 10 days for 2 hours were organized by the outpatient pain facility of the neurological department of the university of Erlangen. During seminars the patients were informed about these recommendations and learned progressive muscle relaxation. Agreed therapy between physician and patient was documented by physicians and patients during a 6 months treatment interval and compared with the recommended therapy. Effectivity of treatment was assessed by pre-post changes of days of headache/month, attack frequency/month, headache intensity (visual analogue scale), pain related impairment (German version of the Brief Pain Inventory), and health related quality of life (German Version of the SF-36). 51 patients were documented by 24 primary care physicians after communication of recommendations and 46 patients completed the patient seminar. Data of both groups were compared with those of 80 patients from primary care physicians before interventions. RESULTS: Communication of recommendations for headache therapy to primary care physicians did not improve conformity of the agreed therapy with the recommended. Contrary conformity of the agreed therapy for pharmacological treatment of migraine attacks and interval therapy of migraine by progressive muscle relaxation with the recommended therapy improved significantly. However, interventions did not significantly improve the outcome quality of outpatient treatment as compared to the therapy of primary care physicians before interventions. CONCLUSION: Effectivity of headache treatment in primary health care could not be improved by communication of evidence-based recommended therapy to primary care physicians nor by direct information of patients about these recommendations in combination with provided availability to learn progressive muscle relaxation.

Adult↗

Central and peripheral adverse hemodynamic changes during laparoscopic surgery and their reversal with a novel intermittent sequential pneumatic compression device.

OBJECTIVE: To study the influence of a novel intermittent sequential pneumatic compression device (Lympha-press) on the adverse cardiac and peripheral hemodynamic changes induced by positive-pressure pneumoperitoneum (PPPn) in laparoscopic surgery. SUMMARY BACKGROUND DATA: Creation of PPPn is known to cause adverse central and peripheral hemodynamic changes. An intrasubject observational study was undertaken to quantitate these adverse changes and to assess the influence of an intermittent sequential pneumatic compression system on these adverse hemodynamic changes during laparoscopic surgery with PPPn. METHODS: The study involved 16 consecutive patients undergoing laparoscopic surgery with PPPn of 12 mmHg and 30 degrees head-up tilt position. The following peripheral hemodynamic recordings were made using Doppler ultrasound: peak systolic velocity (PSV), end diastolic velocity (EDV), and cross-sectional area of the femoral vein. Central monitoring included cardiac output and stroke volume by transesophageal Doppler, blood pressure, and pulse. The hemodynamic state based on these parameters was assessed before induction of PPPn with the anesthetized patient in the supine position, after induction of PPPn and head-up tilt position with Lympha-press off, and during PPPn and head-up tilt position with Lympha-press on, and after desufflation with the patient in the supine position under general anesthesia. RESULTS: Positive-pressure pneumoperitoneum and the head-up tilt position resulted in a 33% reduction in PSV, a 21% reduction in EDV, and a 29% increase in cross-sectional area of the femoral vein. This was associated with a 20% reduction in cardiac output and an 18% reduction in stroke volume. Activation of Lympha-press during PPPn and the head-up tilt position resulted in a 129% increase in PSV and a 55% increase in EDV by 55%. It also increased the cardiac output by 27% and stroke volume by 16%, with no effect on cross-sectional area. Compared with the pre-PPPn stage, there was no difference in cardiac output or stroke volume, but the PSV was higher by 78% and the EDV by 32%. After abdominal desufflation in the supine position, the cardiac output and stroke volume were restored to the pre-PPPn level, but persistent and significant elevations were observed during the period of study in PSV, EDV, and cross-sectional area. CONCLUSIONS: Significant and individually variable central and peripheral hemodynamic changes are encountered during laparoscopic surgery with PPPn and the head-up tilt position. These are reversed by intermittent sequential pneumatic compression using Lympha-press.

Adult↗

Breast Hematoma Complicating Thrombolytic Therapy.

Thrombolytic therapy (TT) is now established as the main treatment of acute myocardial infarction (MI). Spontaneous breast hematoma, usually a rare complication of anticoagulant therapy, has been described in the last five decades, but not after thrombolytic therapy. We present three patients who developed the rare complication of breast hematoma after TT, out of 495 women treated with TT in ICCU in our hospital, because of acute MI in the last 12 years. One patient needed blood transfusion and in another patient, atypical ductal nuclei were observed in fine needle aspiration (FNA) of breast hematoma, needing further evaluation. As thrombolytic therapy becomes more widespread and essential in treating patients suffering acute occlusion of coronary, retinal, pulmonary or peripheral arteries, it is expected that more women will present with breast hematoma following such treatment.

Journal Article↗

[Outcome-quality of treatment for headache on primary care conditions].

BACKGROUND: Little is known about the outcome-quality of treatment for headache on primary care conditions in Germany. METHODS: All physicians (2100) of middle franconia, a bavarian greater district with 1,6 Mio. inhabitants, involved in outpatient management were asked to include consecutively patients in the study which suffer from migraine (at least 2 attacks/month) and/or tension type headache (at least 8 days/month) of at least 4 weeks duration. Before and after a 6 months interval patients documented the following outcome data in a questionnaire: pain intensity during the last attack (numeric rating scale), pain dependent disability (Brief Pain Inventory, German version), health related quality of life (SF-36, German version) and depressivity (Allgemeine Depressionsskala). The pain chronification state (Mainz Pain Staging System) has been assessed by the physician. Therapy was not standardized and included the natural spectrum of medicamental and non-medicamental therapy of headache. Agreement of therapy with recommendations of the "Arzneimittelkommission der Deutschen Aerzteschaft" has been assessed. RESULTS: 24 physicians participated in the study. Pre-post-data of 80 patients (46+/-14 y) could be analysed. Initially 67% were classified in pain chronification state I, 27% in state II and 6% in state III. Medicamental therapy agreed with recommendations in approximately 50% of patients, non-medicamental therapy has been used rarely. The pain intensity, pain dependent disability, depression and quality of life improved significantly. 45% and 55% of patients improved in at least 2 of 6 outcome-parameters by 30% of baseline value or by half standard deviation of the corresponding pre-post-differences, respectively. The latter outcome-measure reflects a medium effect size. CONCLUSIONS: On primary care conditions about 50% of patients suffering from migraine and/or tension type headache (predominantly low chronification stae) perceive a therapy effect that corresponds to a medium effect size.

English Abstract↗

Density of sympathetic axons in sural nerve biopsies of neuropathy patients is related to painfulness.

In this study, differences of unmyelinated nerve fiber density in sural nerve biopsy material from patients suffering from neuropathies of unknown origin with (n=14) or without pain (n=13) were analyzed. Immunocytochemistry was applied to differentiate afferent sensory and efferent sympathetic nerve fibers. All patients were evaluated for deficits of small fiber function with thermotesting, quantitative sudomotor-axon reflex-testing and testing of painfulness of mechanical stimuli before performing the biopsy. No difference was found between patients with and without pain concerning clinical deficits or results in any of the neurophysiological examinations. There were also no histopathological differences concerning the density of afferent C-fibers. However, absolute and relative density of efferent sympathetic nerve fibers was significantly higher in patients with painful neuropathy (P<0.001), although none of the patients demonstrated clinical sympathetic abnormalities. We conclude that an imbalance between afferent and sympathetic nerve fiber density in the periphery may contribute to neuropathic pain even in those patients without obvious clinical autonomic disturbances.

Adult↗

[Structure quality in outpatient care of chronic pain patients].

BACKGROUND: Outcome quality of medical treatment depends on structure quality of the treatment facility. In the present study we tried evaluate structural parameters of outpatient treatment facilities relating to management of headache, low back pain and cancer pain. METHODS: 109 outpatient treatment facilities (104 offices, 3 outpatient departments of hospitals, 2 pain ambulances of hospitals) in middle franconia, one of the larger Bavarian administrative division (population: 1,6 Mio.), have been evaluated by questionnaires. Questions examined certain structural conditions of the treatment facility as compared to german guidelines for outpatient treatment of pain patients ("Schmerztherapievereinbarung"). RESULTS: Only one treatment facility worked within an interdisciplinary setting. Less than 25% (median) of total patients of an outpatient treatment facility suffered from acute or chronic headache, low back pain or cancer pain. 38% of physicians participated regularly on pain conferences. Established methods for diagnosis and documentation of patients suffering from chronic headache, chronic back pain and cancer pain were regularly used by 16%, 12% and 10% of physicians, respectively. Regular interdisciplinary cooperation in the management of patients with chronic headache, chronic back pain and cancer pain was indicated by 28%, 24% and 41% of physicians, respectively. However, personal discussion of patient related problems took place in less than 5% of physicians. Although a considerable number of different therapies (included as standard therapy for outpatient management of chronic pain in the "Schmerztherapievereinbarung") can be applied in each outpatient treatment facility (median:5), psychological therapy for management of chronic headache, chronic back pain and cancer pain was used regularly by 5%, 2% and 7% of physicians, respectively. Scoring of all examined structural parameters provides a measure for the quality of the parameters of a certain outpatient treatment facility as compared to that of an optimal outpatient facility for pain treatment (quality score=100%). However, 75% of examined outpatient treatment facilities reached quality scores only up to 43%. CONCLUSIONS: There are considerable structural deficits in outpatient treatment facilities involved in management of patients suffering from chronic headache, chronic back pain and cancer pain. Realisation of standards according to the "Schmerztherapievereinbarung" needs organisation of an interdisciplinary network between the different specialties necessary for pain management. Interdisciplinary cooperation should be supported by the official organization of the medical self-government in Germany--the Kassenärztliche Vereinigung--which has to assure optimal conditions for outpatient treatments.

English Abstract↗

A simplified laparoscopic technique for mesh placement in ventral hernia repair.

The use of a large synthetic mesh for laparoscopic repair of significant ventral abdominal wall defects may be accompanied by technical difficulties resulting from improper orientation and positioning of the mesh over the defect. We suggest a technique based on initial fixation of the mesh center to the central point of the defect, and subsequent centrifugal attachment of the mesh to the abdominal wall. This technique is advantageous because it leads to precise orientation and positioning of the synthetic patch and to significant reduction of the time needed for its reinforcement over and around the defect.

Hernia, Ventral↗