Search results for "dynamics"
showing 10 items of 9782 documents
A longitudinal single-center cohort study on the prevalence and risk of accessory saphenous vein reflux after radiofrequency segmental thermal ablati…
2015
Objective Endothermal ablation has become a commonly used technology for occlusion of refluxing great saphenous veins (GSVs). However, the risk for primarily untreated accessory saphenous veins (ASVs) to develop reflux during follow-up has not yet been defined. Here, the prevalence and risk of ASV reflux is explored. Methods During a prospective multicenter cohort study on radiofrequency segmental thermal ablation of refluxing GSVs, the presence and reflux status of ASVs were monitored in 93 legs in a single center. Control examinations were performed after 1 week and at 12, 24, 36, and 48 months. Life-table and multiple regression analyses were used to describe frequency and risk factors f…
Insulin resistance and glomerular hemodynamics in essential hypertension
2002
Insulin resistance and glomerular hemodynamics in essential hypertension. Background Arterial hypertension is an important cause of end-stage renal failure. Insulin has been shown to modify glomerular hemodynamics in hypertensive subjects. The aim of this work, therefore, was to observe the relationships between renal hemodynamics and insulin resistance in arterial hypertension. Methods Sixty-two non-diabetic hypertensive patients and 25 healthy normal subjects were studied. Renal plasma flow and the glomerular filtration fraction were determined by renoscintigraphy and the insulin sensitivity by an oral glucose test. Results Renal plasma flow in hypertensive subjects was lower than expecte…
Conditional Self-Entropy and Conditional Joint Transfer Entropy in Heart Period Variability during Graded Postural Challenge.
2015
Self-entropy (SE) and transfer entropy (TE) are widely utilized in biomedical signal processing to assess the information stored into a system and transferred from a source to a destination respectively. The study proposes a more specific definition of the SE, namely the conditional SE (CSE), and a more flexible definition of the TE based on joint TE (JTE), namely the conditional JTE (CJTE), for the analysis of information dynamics in multivariate time series. In a protocol evoking a gradual sympathetic activation and vagal withdrawal proportional to the magnitude of the orthostatic stimulus, such as the graded head-up tilt, we extracted the beat-to-beat spontaneous variability of heart per…
Mid-Term Effectiveness of Behavioral and Psychodynamic Inpatient Treatments of Severe Obesity Based on a Randomized Study
2006
<i>Background:</i> The objective of this study was to compare the effectiveness of psychodynamic and behavioral inpatient treatments of severely obese patients regarding weight and distress. <i>Methods:</i> In a longitudinal study obese patients (body mass index, BMI ≧35) were randomly assigned to behavioral or to psychodynamic inpatient treatment. Mostly female (n = 267; 85%) obese patients with psychiatric and somatic comorbidity (age 20–64 years, BMI 35–74) were examined with standardized self-report scales on distress (SCL-90R), interpersonal problems (Inventory of Interpersonal Problems), eating behavior (Fragebogen zum Essverhalten) and body image (Fragebogen z…
Hemodynamic and ventilatory changes during implant surgery with intravenous conscious sedation
2010
Purpose: This study was conducted to determine the hemodynamic and ventilatory changes during implant surgery with intravenous conscious sedation, and whether preoperative anxiety, gender or age influence these parameters. Patients and Methods: A prospective study carried out between May 2004 and February 2007, on 102 patients treated with dental implants under local anesthesia and conscious intravenous sedation. Patients completed a questionnaire prior to surgery to evaluate preoperative dental anxiety using Corah's scale. The hemodynamic and ventilatory changes were evaluated by monitoring systolic pressure (SP), diastolic pressure (DP), heart rate (HR) and oxygen saturation (SaO2). These…
Adrenalectomy for Bilateral and Recurrent Pheochromocytoma: Increased Intraoperative Risk?
2006
Adrenalectomy for pheochromocytoma is per se associated with a specific intraoperative cardiovascular risk caused by catecholamine secretion during manipulation of the tumor. Bilateral or multiple, and recurrent chromaffine tumors are special subentities with a potentially more intensified and longer surgical preparation. The aim of our study was to examine these effects on hemodynamic changes compared with those observed for primary, solitary tumors. Of the 82 studied interventions between February 1992 and May 2005, 58 were seen to involve primary, unilateral tumors, 17 involved bilateral (1 trilateral) findings, and there were 7 cases of recurrency. The hemodynamic changes related to pri…
Glucose insulin potassium infusion improves systolic function in patients with chronic ischemic cardiomyopathy
2002
Objective: We assessed the effects of glucose–insulin–potassium (GIK) by echocardiography in stable patients with ischemic dysfunction. Methods: Twelve male patients with stable coronary disease (SCD) and ejection fraction (EF) <45% were studied for systolic function. GIK (glucose 30%, 300 insulin units and KCl 6 g/l) was infused at 1 ml/kg per h over 20 min. Hemodynamic and echocardiographic measurements were recorded at rest (T0), at the end (20 min) of GIK infusion (T + 20), 20 and 40 min after the end of the infusion (T + 40 and T + 60). Results: At T + 20, a significant decrease in WMSI (wall motion score index) was observed compared with T0 (2.16±0.14 vs. 2.30±0.16: P<0.05). An increa…
Pulmonary balloon angioplasty of chronic thromboembolic pulmonary hypertension (CTEPH) in surgically inaccessible cases.
2003
Abstract The clinical course of patients suffering from chronic thromboembolic pulmonary hypertension (CTEPH) depends on the distribution pattern of the thromboembolic material. In patients with thromboembolic findings in the central pulmonary segments pulmonary thrombendarterectomy (PTE) has excellent results and acceptable operative risk. This paper presents two surgically inaccessible cases that were successfully treated with balloon pulmonary angioplasty. Balloon angioplasty improved parenchymal perfusion, increased cardiac index (Delta CI +19.2 % [Case 1], and +15.4 % [2]), reduced pulmonary vascular resistance during follow-up (Delta PVRI -25.0 % [1] and -15.9 % [2]), and is discussed…
Absence of tolerance in duodenal ulcer patients treated for 28 days with a bedtime dose of roxatidine or ranitidine
1996
There is much experimental work on the occurrence of tolerance to the antisecretory effect of H2-receptor antagonists in healthy subjects, while data on its development in patients with duodenal ulcer are poor and conflicting. Moreover, this phenomenon has not been studied previously with 24 h gastric pH-metry in patients with active duodenal ulcer. For these reasons, we carried out a prospective pharmacodynamic investigation in 48 patients with endoscopically proven duodenal ulcer using the well-established once daily dosing schedule of H2 blockers. They were studied by means of 24 h continuous endoluminal pH-metry which was performed before, on d1 and d28 after receiving an oral bedtime d…
Residual urine volume after total mesorectal excision: an indicator of pelvic autonomic nerve preservation? Results of a case-control study.
2004
Objective The rate of bladder dysfunctions after total mesorectal excision (TME) for rectal cancer can be decreased by bilateral pelvic autonomic nerve preservation (PANP). However, it is not clear yet, how often partial nerve impairment may lead to bladder dysfunction. It was the aim of a case-control study, to examine the residual urine volume in patients before and after TME with and without complete PANP, in order to clarify, whether this parameter allows conclusions on the quality of PANP. Patients and methods Regarding bladder function, a case group (n = 26) without complete PANP was compared with a control group (n = 26) with complete identification and nerve preservation according…