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Sympathetic System (sympathetic + system)
Selected AbstractsThe Morphology of the Cervico-thoracic Sympathetic System in Donkeys (Equus asinus L.)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2009O. Ozgel Summary Five adult donkeys of both sexes, used in applied anatomy classes, and perfused with formalin for teaching purposes, constituted the study material. Ganglion cervicale caudale of the examined materials has observed to exhibit individually variable situation as to extend on the left side of the median line, at the alignment of the first and second intercostal spaces and on the right side between the level of the first and third costa. The ganglion extended more caudally on the right side of median line. The lateral surface of the ganglion was determined to be covered with the m. scalenus medius. On the both sides of the median plane, the ganglion cervicale caudale was seen to be situated on the lateral surface of the m. longus colli. On the left side, the ganglion overlapped the oesophagus in two cadavers and on the right side it was situated within a groove between the m. longus colli and trachea in three cadavers. The rami communicantes received by the ganglion cervicale caudale originated from the eighth cervical and first thoracic spinal segments. The ganglion cervicale caudale was formed by the coalescence of the last cervical and first three thoracic sympathetic ganglia. The ganglion cervicale caudale gave off branches that formed the rami communicantes, plexus cardiacus, n. vertebralis and ansa subclavia. One branch extended from the ganglion to the plexus brachialis. in one specimen, two sympathetic,parasympathetic communicating branches were observed to extend from the ansa subclavia and near by the origin of the truncus sympathicus to the n. vagus. In one of the donkeys examined, a branch originating from the ganglion cervicale caudale on the left side of the median plane was determined to end on the ligamentum arteriosum. A microscopic ganglion structure suggesting the existence of the ganglion cervicale medium was determined in a donkey. [source] Heart Rate Variability in Patients with Essential Hyperhidrosis: Dynamic Influence of Sympathetic and Parasympathetic ManeuversANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2005Dayimi Kaya M.D. Background: Essential hyperhidrosis has been associated with an increased activity of the sympathetic system. In this study, we investigated cardiac autonomic function in patients with essential hyperhidrosis and healthy controls by time and frequency domain analysis of heart rate variability (HRV). Method: In this study, 12 subjects with essential hyperhidrosis and 20 healthy subjects were included. Time and frequency domain parameters of HRV were obtained from all of the participants after a 15-minute resting period in supine position, during controlled respiration (CR) and handgrip exercise (HGE) in sitting position over 5-minute periods in each stage. Results: Baseline values of HRV parameters including RR interval, SDNN and root mean square of successive R-R interval differences, low frequency (LF), high frequency (HF), normalized unit of high frequency (HFnu), normalized unit of low frequency (LFnu), and LF/HF ratio were identical in two groups. During CR, no difference was detected between the two groups with respect to HRV parameters. However, the expected increase in mean heart rate (mean R-R interval) did not occur in hyperhidrotic group, whereas it did occur in the control group (Friedman's P = 0.000). Handgrip exercise induced significant decrease in mean R-R interval in both groups and no difference was detected between the two groups with respect to the other HRV parameters. When repeated measurements were compared with two-way ANOVA, there was statistically significant difference only regarding mean heart rate in two groups (F = 6.5; P = 0.01). Conclusion: Our overall findings suggest that essential hyperhidrosis is a complex autonomic dysfunction rather than sympathetic overactivity, and parasympathetic system seems to be involved in pathogenesis of this disorder. [source] The ,false' non-recurrent inferior laryngeal nerveBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 9 2000M. Rafaelli Background A communication between the middle cervical sympathetic ganglion (MCSG) and the inferior laryngeal nerve (ILN) has been described. The anastomotic branch (sympathetic,inferior laryngeal anastomotic branch; SILAB) is usually thin, but is sometimes larger and has the same diameter as the ILN. The purpose of this study was to evaluate prospectively the frequency of this condition and its implications during neck exploration. Methods From November 1998 to October 1999, 791 neck explorations were performed: 677 for thyroid, 99 for parathyroid and 15 for concomitant lesions. Some 1253 ILNs were dissected: 656 (52·3 per cent) on the right and 597 (47·7 per cent) on the left side. Results The ILN was identified in all cases. On the right side a non-recurrent ILN (NRILN) was found in three patients (0·5 per cent) and a large SILAB in ten (1·5 per cent). No anomalous branch was found on the left side. The SILAB originated from the superior cervical sympathetic ganglion (SCSG) in two patients and directly from the sympathetic chain (SC) above the MCSG in eight. No branch originating from the MCSG was found. The SILAB connected with the ILN less than 2 cm from the cricoid in all patients. Conclusion The SILAB may originate not only from the MCSG but also from the SCSG and directly from the SC. When the SILAB is as large as the ILN, it could be mistaken for a NRILN. Before concluding that the anomalous branch is a NRILN, one should check if it originates from the vagus or from the cervical sympathetic system. Awareness of this anatomical condition during neck exploration may help the surgeon to avoid injuries of an ILN running in the usual pathway. © 2000 British Journal of Surgery Society Ltd [source] Treatment of congestive heart failure , current status of use of digitoxinEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue S2 2001G. G. Belz Digitalis glycosides exert a positive inotropic effect, i.e. an increase in myocardial contractility associated with a prolongation of relaxation period, and glycosides lower the heart rate (negative chronotropic), impede stimulus conduction (negative dromotropic) and promote myocardial excitability (positive bathmotropic). They seem to influence the activities of both the vagal and the sympathetic systems. Digitalis glycosides that belong to different substance classes are closely comparable concerning pharmacodynamics but differ substantially in regard to pharmacokinetics. Digoxin and its derivatives are less lipophilic, show lower protein binding and shorter half-life, are mainly eliminated via the kidney and accumulate rather rapidly in cases of insufficient kidney function. Digitoxin is highly lipophilic and extensively bound to plasma proteins, has a longer half-life, is mainly eliminated in the metabolized state via urine and faeces and does not accumulate in kidney dysfunction. As a result of a more stable pharmacokinetic profile, the incidence of toxic side effects seems to be lower with digitoxin than with digoxin. Since the beginning of the 1990s, the antagonists of the RAAS qualified as the standard treatment for congestive heart failure, often in combination with diuretics, vasodilators or ,-antagonists. However, the important role of digitalis glycosides as therapeutic comedication or alternative was never denied, especially in atrial fibrillation with tachycardia. The PROVED and RADIANCE trials proved a detrimental effect of the withdrawal of digoxin therapy on exercise capacity, left-ventricular ejection fraction and clinical symptoms. The DIG trial revealed that digoxin comedication in sinus rhythm patients with congestive heart failure was associated with a lower morbidity (as taken from death or hospitalization because of worsening heart failure) and an unchanged overall mortality , being a unique feature among the available inotropic drugs. Comparable studies for digitoxin have not yet been performed but, because of its higher pharmacological stability, it might well be associated with even more advantages in this regard than digoxin. [source] Ultrafiltration and Dry Weight,What Are the Cardiovascular Effects?ARTIFICIAL ORGANS, Issue 3 2003Article first published online: 2 APR 200, Bernd G. Stegmayr Abstract: Long-term prognosis in dialysis is poor compared to that in healthy control persons. A worsening of the prognosis is noted especially for patients who at initiation of dialysis have congestive heart failure, ischemic heart disease, or left ventricular dysfunction or hypertrophy. This is the main reason that cardiovascular causes are the most common for morbidity in these patients. The weight obtained when normal urine output is present is the dry weight. With reduced ability to excrete the volume by the kidneys in end-stage renal disease (ESRD), the body will retain water and the patient will gain weight. This extra weight is due to volume overload. While volume overload may induce a rise in blood pressure, if the heart is in acceptable condition, a fast removal of fluid by ultrafiltration (UF) during dialysis may instead cause hypotension. Ultrafiltration failure in peritoneal dialysis (PD) patients may lead to successive water retention and overhydration with subsequent cardiac failure, while volume overload may occur over a few days in hemodialysis (HD) patients. Anemia or even too-high hematocrit may impair cardiac function further and worsen conditions caused by wrong dry weight. Thus, during long-term and sustained volume overload, left ventricular (LV) hypertrophy will occur in an eccentric manner. A sustained overload then may lead to cell death and LV dilatation and, eventually, systolic dysfunction. Once a severe left ventricular dilatation has developed, the blood pressure may decrease during volume overload. A worsened prognosis is seen if malnutrition and low albumin levels are present. Volume overload necessitates ultrafiltration to achieve dry weight. Thereby, volume contraction contributes to exaggerated stimulation of or response to activation of the RAS and alpha-adrenergic sympathetic systems. If ultrafiltration goes beyond these compensatory mechanisms, hypotension will occur and increase the risk for hypoperfusion of vital organs. Such episodes may cause cardiac morbidity, aspiration pneumonia, vascular access closure, or neurological complications (seizures, cerebral infarction), besides a more rapid lowering of residual renal function. Preventive measures are, first, finding the right dry weight; second, minimizing interdialytic weight gain; third, optimizing the target for hemoglobin (110,120 g/l); fourth, lowering dialysate calcium (1.25 mmol/l); and fifth, eventually using higher dialysate potassium if long dialyses are performed. [source] |