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Biomedical subjects

K Schimrigk

Publications and source records attributed to K Schimrigk.

At least 73 records · Page 4Linked to original sources
PubMed1996

Time course of the acetazolamide effect in patients with extracranial carotid artery disease.

The acetazolamide test of cerebrovascular reserve is performed as a two-point transcranial Doppler (TCD) measurement of the flow velocity in the middle cerebral artery (MCA) before and 15 to 20 minutes after injection of the carbonic anhydrase inhibitor. The time course was evaluated by bilateral TCD monitoring over 45 minutes in 51 patients with extracranial carotid artery disease. Twenty-nine patients in Group 1 showed a unilateral and 22 patients in Group 2, a bilateral stenosis of the internal carotid artery (ICA). Thirty-one normal hemispheres in 18 normal subjects provided baseline control values. The most useful parameter for the description of the time course was the integral of the mean flow velocity. In both groups integral of the mean flow velocity was significantly reduced compared to that in normal persons (Group 1: 587.2 +/- 538.3 cm, p < 0.01; Group 2: 728.9 +/- 397.1 cm, p < 0.01; normal persons: 967.8 +/- 350.0 cm). The maximal increase of mean flow velocity in a two-point measurement also was significantly lower in the patient groups, but did not reach the same level of significance in Group 2 (Group 1: 19.6 +/- 12.3 cm/sec, p < 0.01; Group 2: 24.2 +/- 10.4 cm/sec, p < 0.05). Thirty-four of 73 hemispheres had reduced integral of the mean flow velocity, but only 29 had a reduced maximal increase. These data indicate that continuous monitoring and evaluation of the time course of the acetazolamide effect provide additional information on cerebrovascular reserve and help to detect an increased number of patients with impaired cerebrovascular reserve.

Acetazolamide↗
PubMed1996

Decrease of fibronectin following repeated infusion of highly substituted hydroxyethyl starch.

OBJECTIVE: Fibronectin (Fn) plays an important part in unspecific defense mechanisms because of its ability to mediate the binding of foreign-body particles, bacteria, collagen, and other macromolecules to phagocytising cells of the reticulo-endothelial system (RES). The aim of the present study was to examine the effect of a 10-day hemodilution therapy on Fn concentration in humans. DESIGN: The patients were randomized and treated with either 10% hydroxyethyl starch (HES) 200/0.62 or 6% HES 200/0.62. SETTING: Neurology department of an university clinic. PATIENTS: We examined 12 patients with cerebrovascular perfusion disturbances. INTERVENTIONS: The Fn concentration was determined using simple radial immunodiffusion. RESULTS: The Fn concentration dropped significantly in all 12 patients (p < 0.01) in a dose-dependent manner beyond the dilution effect. 10% HES 200/0.62 caused a Fn decrease from 26.6 +/- 9.2 to 10.0 +/- 2.2 mg/dl (-62.2%), 6% HES reduced Fn from 25.5 +/- 9.9 to 15.0 +/- 3.2 mg/dl (-41.1%). In one patient there was a continuous decrease of Fn from 41.0 down to only 6.4 mg/dl. CONCLUSION: According to the results of animal experiments, the decrease of Fn seems to indicate depression of the RES. Besides its defense function, Fn probably plays a role in embryogenesis, wound healing, and blood clotting. Therefore, we assume that the drug-induced reduction of Fn possibly has clinical relevance.

Animals↗
PubMed1996

Vasomotor reactivity and pattern of collateral blood flow in severe occlusive carotid artery disease.

BACKGROUND AND PURPOSE: The compromise of cerebrovascular autoregulation in severe occlusive carotid artery disease depends on the functional capacity of collateral pathways. In previous reports correlating hemodynamic disturbances with collateral pathways, collateral blood supply was often evaluated by invasive cerebral angiography. In this study noninvasive transcranial Doppler ultrasound was used to determine both collateral pathways and vasomotor reactivity. METHODS: With the use of blood flow direction, compression tests, and evident side-to-side asymmetries of blood velocities, the collateral supply through the anterior and posterior communicating arteries, the ophthalmic artery, and leptomeningeal anastomoses was evaluated by transcranial Doppler ultrasound in 48 patients (42 men, 6 women; mean +/- SD age, 59 +/- 9 years) with occlusion (n = 36) or stenosis of more than 90% (n = 12) of one internal carotid artery. Ipsilateral vasomotor reactivity was determined by the percent increase of middle cerebral artery mean blood velocity with the use of (1) the breath-holding maneuver and (2) acetazolamide (1 g IV) as vasodilatory stimulus. Additional stenoses (50% to < 90%) of the contralateral internal carotid artery were present in 20 of the 48 patients. RESULTS: Vasomotor reactivity was not affected by the presence of a contralateral internal carotid artery stenosis. Both vasodilatory stimuli similarly indicated poor vasomotor reactivity when an ophthalmic or a leptomeningeal pathway accompanied an anterior communicating artery pathway compared with a lone anterior communicating artery pathway (P < .05). The acetazolamide challenge indicated significantly better preserved vasomotor reactivity when blood supply was provided through a lone anterior communicating artery pathway (66 +/- 30%) than through an anterior and posterior communicating artery pathway (33 +/- 20%, P < .05), whereas the breathholding method failed to show such a difference. CONCLUSIONS: The presence of an ophthalmic artery pathway may provide the first evidence of disturbed vasomotor reactivity. The use of cerebral angiography to evaluate collateral pathways must be considered carefully since transcranial Doppler ultrasound is a reliable noninvasive alternative.

Acetazolamide↗
PubMed1996

[Electrophysiologic diagnosis in erectile dysfunction].

So far, electrophysiological examinations have rarely been used in the diagnosis of erectile dysfunction (ED) mainly because the methods available only allow somatic neuron pathways to be examined whose relevance for the mainly autonomically controlled crection is evaluated differently. At present, impaired penile nerve supply as the possible cause of ED can only be evaluated through neurophysiological screening of the somatic and autonomic pathways of the pelvic floor, and not just by one simple method. Diagnosing ED should include testing of motoric efferences through electroneurography of the pudendal nerve and electromyography of the external anal sphincter and the urethral sphincter. Sensitive afference is tested with somatosensory evoked potentials of the pudendal nerve. New methods that are available for the examination of autonomic pathways are the penile sympathetic skin response and the EMG of the corpus cavernosum. Together with the other electrophysiological examinations, they allow neurogenic causes to be determined and differentiate not only between central and peripheric lesions, but also between acute and chronic changes. Prognosis can also be estimated. A crucial diagnostic deficit is the fact that it is still not possible to test the parasympathetic system directly.

Autonomic Nervous System↗
PubMed1996

[Decrease of thrombocyte volume after several days infusion of highly substituted medium molecular weight hydroxyethyl starch (HAES 200/0.62)].

Dextrans are known to inhibit platelet aggregation. However, conflicting results have been reported with hydroxyethyl starch (HES), usually administered as a single dose. To clarify this, we studied the effects of HES on platelet number, aggregation and volume during the course of long-term hemodilution therapy. Twelve patients with disturbances of cerebrovascular perfusion were randomized and divided into two groups of 6 patients each. One group was treated with 10% HES 200/0.62, the other with 6% HES 200/0.62. The patients in group 1 received a loading dose of 500 ml, followed by 500 ml daily for 10 days. Group 2 patients were infused a loading dose of 500 ml, followed by 1000 ml on days 1 to 4 and 500 ml on days 5 to 10. 10% HES had a larger volume effect. The hematocrit was lowered by 19.0%, whereas 6% HES caused a decrease of only 15.6%. 10% HES lowered the platelet number significantly (p < 0.05) by 5.8%, 6% HES did not lower the platelet number significantly. Platelet volume decreased significantly during therapy (p < 0.05) in both groups. 10% HES reduced the platelet volume by 13.9%, the reduction with 6% HES was 9.0%. Under therapy with 10% HES, platelet aggregation declined slightly, but significantly (p < 0.05), whilst no effect was seen with 6% HES. During long-term hemodilution therapy with HES, the initial decrease in platelet number, which is due to dilution, is quickly compensated. The continuous decline in mean platelet volume during therapy is probably due to colloid-osmotic shrinkage. Since there is a positive correlation between platelet size and function, the slight inhibition of platelet aggregation caused by 10% HES is possibly due to the observed decline in platelet volume.

Blood Platelets↗
PubMed1996

[Urinary incontinence in patients with Parkinson syndrome].

Disturbances of micturition are very common in Parkinson's disease. Hence, we assessed 50 patients (22 female, 28 male, average age: 59.8 years) by means of the Gaudenz score. In 31 cases (62%) normal findings were obtained. Urge incontinence was diagnosed in 13 cases (26%) and stress incontinence in 5 patients (10%). One patient had both urge and stress incontinence. All patients with stress incontinence were female.

Aged↗
PubMed1996

["Thunder clap headache": an independent form of headache?].

Acute severe headache indicative of subarachnoid haemorrhage (SAH), but without the requisite proof, is defined as thunderclap. A special pathophysiological mechanism for the development of this headache is not known as yet. This retrospective study comprised 84 patients. All had the typical clinical signs of a SAH, but cranial computer tomography and lumbar puncture excluded this diagnosis. In 82% of these patients the headache was classified according to aetiologically defined symptomatic groups. One patient with headache of vascular aetiology had an angiographically proven, but not ruptured aneurysm. No definite cause for the headache was found in 18% of cases. None of the patients followed up over a period of between 12 months and 6 years developed SAH or any other severe neurological disorder. 9% reported repeat of the headache event. Thunderclap headache seems to be only a descriptive term for patients with symptoms typical of a SAH without signs of bleeding. Thunderclap headache has no diagnostic or prognostic specificity and therefore we recommend use of this term only as a description of the headache characteristic. Thunderclap headache is not a predictor of a future SAH. Cerebral angiography should be restricted to cases with neurological deficits.

Adolescent↗
PubMed1996

Influence of low and medium molecular weight hydroxyethyl starch on platelets during a long-term hemodilution in patients with cerebrovascular diseases.

It is a well-known fact that plasma substitutes reduce the number of platelets after one-time administration due to a dilution effect. So far, it has not been sufficiently investigated how a long-term hemodilution therapy affects platelet number, volume distribution and function. In 20 patients with cerebrovascular diseases a 10-day hemodilution therapy was carried out. The patients were randomly and double-blind treated with either medium molecular weight (MMW) hydroxyethyl starch (HES) 200/0.5 or low molecular weight (LMW) HES 40/0.5. On the first day of therapy, both groups showed a significant reduction in the number of platelets (-13.2% and -8.4%, respectively, p < 0.05), which was smaller than the dilution effect. During the course of the therapy, the platelet number increased, reaching its initial value. Mean platelet volume decreased in both groups significantly (MMW HES -4.7%, p < 0.05, LMW HES -4.6%, p < 0.01). The share of large platelets decreased disproportionately (MMW HES -15.4%, p < 0.01, LMW HES -11.4%, p < 0.01). Spontaneous platelet aggregation was not affected by HES. During the course of a long-term hemodilution therapy, the initial dilution-induced drop in platelet number is quickly compensated. The decline in mean platelet volume, which increases towards the end of the therapy, is due to a great extent to a decline in the number of large platelets. This in turn is probably caused by a colloid-osmotic shrinkage of the platelets and increased degradation. There were no signs for a clinically relevant impairment of platelet function.

Blood Platelets↗
PubMed1995

[Blood pressure and hormonal regulation in active and passive orthostasis].

UNLABELLED: The procedure using a tilt-table is far better standardized and less dependent on the patient's compliance compared to the active manoeuvre of standing up. The object of this study is to detect to what extent results are comparable concerning hormonal regulation and the adaptation of blood pressure. In 20 males (59.1 +/- 10.9 years), without any evidence of central nervous disorder, we measured the systolic, diastolic and the median blood pressure, heart frequency and hormone levels (noradrenaline, aldosterone, renin) at rest and over 10 minutes in the upright position after actively or passively (by tilt-table) assuming an orthostatic posture. The blood pressure showed little change after the patient sat upright himself, whereas the passive manoeuvre caused a significant decline of systolic blood pressure lasting over the entire sampling period. The adaptation of hormone levels and heart frequencies, however, showed no significant differences. Renin and aldosterone rose in both examinations. Noradrenaline showed an increase of 100% after active assumption of orthostatic posture and 80% using the tilt-table. Hence in patients who are passively brought into the upright position there is no increased noradrenaline output to stabilize blood pressure. This points to the fact that orthostatic circulatory mechanisms are not sufficiently brought into play after the non-physiological passive manoeuvre. IN CONCLUSION: (1.) the tilt-table compared to active orthostatic posture provides better standardized conditions; (2.) there are no significant differences in hormone levels; and (3.) maneuvering patients into an upright position provides a greater risk of fainting due to a pathological fall in blood pressure.

Aged↗
PubMed1995

Double-blind crossover study with levorotatory form of hydroxytryptophan in patients with degenerative cerebellar diseases.

OBJECTIVE: To determine whether treatment with the levorotatory form of hydroxytryptophan (L-5-hydroxytryptophan), a controversial experimental drug, can improve the conditions of patients with ataxia. DESIGN: A double-blind crossover study with the levorotatory form of hydroxytryptophan was performed in 39 patients with degenerative cerebellar diseases. SETTING: Patients were selected from an ongoing prospective follow-up study at two university hospitals. PATIENTS: We studied 19 patients with Friedreich's ataxia, 13 with cerebellar atrophy, and seven with olivoponto-cerebellar atrophy. INTERVENTION: The levorotatory form of hydroxytryptophan was given orally in a dose of 1000 mg/d. Each treatment phase, with the levorotatory form of hydroxytryptophan or the placebo, lasted 10 months, after which the treatment of patients was crossed over to the other phase. MAIN OUTCOME MEASURES: Ataxia was documented and quantified by using a clinical score, posturography, and measurement of grip force and the rapid-syllable repetition rate. RESULT: The levorotatory form of hydroxytryptophan had no significant effect on cerebellar symptoms. CONCLUSION: Long-term treatment with a high dose of the levorotatory form of hydroxytryptophan does not improve the conditions of patients with ataxia.

5-Hydroxytryptophan↗
PubMed1995

Pattern of elevation of urine catecholamines in intracerebral haemorrhage.

Autonomic nervous system dysfunction is a common complication of severe intracranial disease. The aim of this study was to reveal the autonomic changes in patients suffering from acute intracerebral haemorrhage (ICH). 25 patients with spontaneous ICH within 24 hours of onset of symptoms were included. All patients were treated with standardised medical management and the meta- and normetanephrines were detected by high performance liquid chromatography (HPLC) in 24-hour urine every day. The mean level of normetanephrine (709 +/- 579 micrograms/day) and metanephrine (244 +/- 161 mg/day) were significantly elevated in comparison with a control group, p < or = 0.01. The norepinephrine elevation was of greater diagnostic and prognostic importance. Maximum urinary catecholamine metabolite levels occurred between day 3 to 10 after the bleeding. Normetanephrines correlated with the prognosis and the complications of ICH: intraventricular involvement resulted in significantly elevated normetanephrine levels (896 +/- 520 micrograms/day versus 311 +/- 78 micrograms/day) p < or = 0.01. Patients with a great volume of haematoma developed severe autonomic dysregulation (normetanephrines 1114 +/- 493 micrograms/day), whereas patients with smaller haematoma did not (339 +/- 125 micrograms/day) p < or = 0.0001; patients with bad outcome (1014 +/- 620 mg/day) had higher levels of normetanephrines than those with a good prognosis (322 +/- 110 micrograms/day) p < or = 0.001. A close relationship to elevated intracranial pressure was established. This study demonstrated the feasibility of detecting autonomic nervous system dysfunction in neurological intensive care patients by means of examination of the metabolites of the catecholamines in the urine.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Disorders of eye movement in amyotrophic lateral sclerosis--report of 2 patients].

BACKGROUND: Amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder of unknown origin, was thought to spare the extraocular muscles. Extraocular involvement has recently been reported to occur in the late stages of ALS following respiratory insufficiency. CASE REPORT: We report on two patients with ALS who were referred for screening of oculomotor impairment in ALS. Orthoptic examination in a 64-year-old woman with peripheral ALS revealed retraction of the upper eye lids as well as impaired abduction and upgaze in both eyes, developing prior to respiratory insufficiency. A 50-year-old man with bulbar ALS was found to have bilateral impairment of upgaze as well as a negative Bell's phenomenon. Horizontal pursuit was interrupted by compensatory saccades, vertical fixating saccades were slightly hypometric. These oculomotor changes were also seen prior to respiratory insufficiency. CONCLUSION: These findings provide further evidence of early oculomotor involvement in ALS, e.g. prior to respiratory failure and prior than previously suspected. Oculomotor impairment may occur in both the peripheral and the bulbar type of ALS.

Amyotrophic Lateral Sclerosis↗