"Sympathectomy is a technique about which we have limited knowledge, applied to disorders about which we have little understanding." Associate Professor Robert Boas, Faculty of Pain Medicine of the Australasian College of Anaesthetists and the Royal College of Anaesthetists http://www.pfizer.no/templates/Page____886.aspx
cell body reorganization in the spinal cord after sympathectomy
The amount of compensatory sweating depends on the patient, the damage that the white rami communicans incurs, and the amount of cell body reorganization in the spinal cord after surgery.
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf
After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.
http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf
After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.
http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract
Saturday, May 28, 2011
After unilateral sympathectomy the incidence of calcified arteries on the side of operation was significantly higher than that on the contralateral side
Medial arterial calcification is frequently seen in diabetic patients with severe diabetic neuropathy. Sixty patients (19 diabetic and 41 non-diabetic) were examined radiologically for typical Monckeberg's sclerosis of feet arteries 6-8 years after uni- or bilateral lumbar sympathectomy. Fifty-five out of 60 patients (92%) revealed medial calcification. This calcification was observed in both feet of 93% of patients, who had undergone bilateral operation. After unilateral sympathectomy the incidence of calcified arteries on the side of operation was significantly higher than that on the contralateral side (88% versus 18%, p less than 0.01). Although diabetic patients showed longer
stretches of calcification than non-diabetic subjects, the difference was not significant in terms of incidence and length. Of 20 patients who had no evidence of calcinosis pre-operatively, 11 developed medial calcification after unilateral operation exclusively on the side of sympathectomy. In seven patients calcinosis was detected in both feet after bilateral operation. In conclusion, sympathetic denervation is one of the causes of Monckeberg's sclerosis regardless of diabetes mellitus.
PMID: 6873514 [PubMed - indexed for MEDLINE]
Diabetologia. 1983 May;24(5):347-50.
stretches of calcification than non-diabetic subjects, the difference was not significant in terms of incidence and length. Of 20 patients who had no evidence of calcinosis pre-operatively, 11 developed medial calcification after unilateral operation exclusively on the side of sympathectomy. In seven patients calcinosis was detected in both feet after bilateral operation. In conclusion, sympathetic denervation is one of the causes of Monckeberg's sclerosis regardless of diabetes mellitus.
PMID: 6873514 [PubMed - indexed for MEDLINE]
Diabetologia. 1983 May;24(5):347-50.
in the media of FAs hypercholesterolemia induces changes similar to those observed in sympathectomized rabbits in non-pathological conditions
In a previous study, we showed that after sympathectomy, the femoral (FA) but not the basilar (BA) artery from non-pathological rabbits manifests migration of adventitial fibroblasts (FBs) into the media and loss of medial smooth muscle cells (SMCs). The aim of the present study was to verify whether similar behaviour of arteries occurred in the pathological context of atherosclerosis.
Our results show that in the media of FAs hypercholesterolemia induces changes similar to those observed in sympathectomized rabbits in non-pathological conditions, i.e., migration of adventitial FBs to the media and loss of medial SMCs. These latter changes, which can be ascribed to pathological events, were accentuated after sympathectomy in the hypercholesterolemic rabbits. The present study reveals that pathological events, including migration and phenotypic modulation of vascular FBs and loss of SMCs, may be under the influence of sympathetic nerves.
Acta Histochemica; Jul2008, Vol. 110 Issue 4, p302-313, 12p
Our results show that in the media of FAs hypercholesterolemia induces changes similar to those observed in sympathectomized rabbits in non-pathological conditions, i.e., migration of adventitial FBs to the media and loss of medial SMCs. These latter changes, which can be ascribed to pathological events, were accentuated after sympathectomy in the hypercholesterolemic rabbits. The present study reveals that pathological events, including migration and phenotypic modulation of vascular FBs and loss of SMCs, may be under the influence of sympathetic nerves.
Acta Histochemica; Jul2008, Vol. 110 Issue 4, p302-313, 12p
sympathectomy results in an increased collagen content in the vascular wall, suggesting a stiffening of the vessel wall
From animal experiments, it is known that long-term sympathectomy results in an increased collagen content in the vascular wall, suggesting a stiffening of the vessel wall (9). Giannattasio et al.
MEDICINE & SCIENCE IN SPORTS & EXERCISE®
Copyright © 2005 by the American College of Sports Medicine
DOI: 10.1249/01.mss.0000174890.13395.e7
MEDICINE & SCIENCE IN SPORTS & EXERCISE®
Copyright © 2005 by the American College of Sports Medicine
DOI: 10.1249/01.mss.0000174890.13395.e7
Sunday, May 22, 2011
hypoxic pulmonary vasoconstriction may be impaired after Sympathectomy
It is well known that hypoxic pulmonary vasoconstriction(HPV) plays an important role to protect hypoxemia during the atelectasis induced by one-lung ventilation. Thoracic sympathectomy may have effects on pulmonary vasculature(HPV) and hemodynamics during one-lung anesthesia.
Mean arterial blood pressure was decreased from 81.9+/-2.89 to 73.2+/-2.49 mmHg after thoracic sympathectomy and heart rate was decreased from 104.4+/-3.12 to 88.2+/-2.31beats/min. Arterial oxygen tension was decressed from 570.5+/-17.9 to 521.4+/-23.2mmHg after position change, and decreased to 271.1+/-28.1 mmHg under one-lung ventilation, and finally decreased to 217.0+/-18.3 mmHg after thoracic sympathectomy. With the above results, we can conclude that patients for TES should be carefully observed during and after the procedure, and hypoxic pulmonary vasoconstriction may be impaired after TES.
Korean J Anesthesiol. 1993 Aug;26(4):695-699.
Mean arterial blood pressure was decreased from 81.9+/-2.89 to 73.2+/-2.49 mmHg after thoracic sympathectomy and heart rate was decreased from 104.4+/-3.12 to 88.2+/-2.31beats/min. Arterial oxygen tension was decressed from 570.5+/-17.9 to 521.4+/-23.2mmHg after position change, and decreased to 271.1+/-28.1 mmHg under one-lung ventilation, and finally decreased to 217.0+/-18.3 mmHg after thoracic sympathectomy. With the above results, we can conclude that patients for TES should be carefully observed during and after the procedure, and hypoxic pulmonary vasoconstriction may be impaired after TES.
Korean J Anesthesiol. 1993 Aug;26(4):695-699.
Unilateral removal of the superior cervical ganglion (SCG) results in the reinnervation of the denervated cerebral vessels by sprouting nerves
Chemical sympathectomy of the mature rat rather than the neonate also leads to sensory hyperinnervation, although there are a few differences. In the lung, sympahtectomy induces a marked increase in CGRP-immunoreactive nerve density around the ariways, blood vessels, and also in the vicinity of the neuroepithelial bodies of the pulmonary epithelium.
Following transection of the preganglionic autonomic nerves or in spinal cord injury, there are marked changes in the nerves that remain. Such changes can be manifested not only as nerve growth and changes in neurotransmitter expression, but remarkably, in reorganization of nerve pathways and their function.Since sprouting is a common response of the nerves that remain following nerve injury, the close association of the different divisions of the autonomic nervous system in the pelvic region opens up the possibility for new connections to form new pathways. Spinal cord injury can unmask spinal reflexes that are normally inhibited by input from higher centers in the brain.
Handbook of the autonomic nervous system in health and disease
By Liana Bolis, J. Licinio, Stefano GovoniInforma Health Care, 2003 - Medical - 677 pagesdepletion of brain noradrenaline levels causes a disturbance in cerebral microvascular tone
A hypertensive condition at a mean arterial pressure of about 160 mm Hg was maintained for 1 hour by intravenous infusion of phenylephrine. In the 6-hydroxydopamine-treated group, CBF increased significantly after the elevation of systemic blood pressure compared with that in the control group, and cerebral autoregulation was impaired. After a 1-hour study, the specific gravity of the cerebral tissue in the treated group significantly decreased; electron microscopic studies at that time revealed brain edema.It is suggested that depletion of brain noradrenaline levels causes a disturbance in cerebral microvascular tone and renders the cerebral blood vessels more vulnerable to hypertension.
Journal of Neurosurgery, December 1991 Volume 75, Number 6
Journal of Neurosurgery, December 1991 Volume 75, Number 6
cerebral edema is worsened by sympathectomy, which causes increased cerebral blood flow
Although excessive SNS activity may be globally harmful, catecholamines and sympathetic nerves may also have organ-protective effects via reflex arteriolar constriction, which may protect the capillaries of the brain and kidney from surges in SBP. A baroprotective role of cerebral sympathetic nerves was uncovered by Heistad et al., who unilaterally denervated the cerebral vasculature in stroke-prone rats and found that fatal stroke occurred rapidly in the hemisphere ipsilateral to the sympathetic denervation. In the syndrome of malignant hypertension, cerebral edema is worsened by sympathectomy, which causes increased cerebral blood flow.
Role of hte Hypothalamus in Integration of behavior and Cardiovascular Responses (p. 60)
Elsevier Health Sciences, 2005 - Medical - 872 pages
Role of hte Hypothalamus in Integration of behavior and Cardiovascular Responses (p. 60)
Hypertension: a companion to Brenner and Rector's the kidney
By Suzanne Oparil, Michael A. WeberElsevier Health Sciences, 2005 - Medical - 872 pages
Spinal Cord Infarction caused by sympathectomy
Uncommon causes include decompression sickness, which has a predilection for spinal ischemic damage; complications of abdominal surgery, particularly sympathectomy; circulatory failure as a result of cardiac arrest or prolonged hypotension; and vascular steal in the presence of an arteriovenous malformation.
Author: Thomas F Scott, MD, Professor, Program Director, Department of Neurology, Drexel University College of Medicine; Director, Allegheny MS Treatment Center
Contributor Information and Disclosures
Contributor Information and Disclosures
Updated: Aug 21, 2009
sympathectomy per se may sensitize peripheral nociceptors and lead to neuralgia
Interestingly, while is used for the treatment of some chronic pain conditions, sympathectomy per se may sensitize peripheral nociceptors to circulating norephinephrine, and this sensitization may lead to post-sympathectomy neuralgia. (p.287)
John Wiley and Sons, 2009 - Medical
Peripheral Receptor Targets for Analgesia: Novel Approaches to Pain Management
By Brian E. CairnsJohn Wiley and Sons, 2009 - Medical
Thursday, May 19, 2011
we conclude that the sympathetic nervous system influences the metabolic activity of the aorta
The effect of chemical sympathectomy with 6-hydroxydopamine (6-OH-DA) on collagen formation in the aortic wall was investigated in rabbits and rats. Eight weeks after 6-OH-DA treatment of rabbits, there was a significant increase an collagen content in aortas and histologic changes in the elastic elements within the media. The possibility of a direct effect of 6-OH-DA on connective tissue formation was investigated in a subsequent experiment in rats. The rates of collagen synthesis and prolyl hydroxylase activity (PHA) were determined in aortas and in the fibrotic granuloma around subcutaneously implanted polyvinylalcohol sponges. Rates of collagen synthesis and PHA were significantly increased in the aortas of 6-OH-DA treated rats, but not in fibrotic granuloma, confirming the changes seen in the aorta of rabbits and suggesting that 6-OH-DA does not directly affect collagen synthesis. We conclude that the sympathetic nervous system influences the metabolic activity of the aorta. Our data indicate that when the aortic wall is deprived of adrenergic nervous stimulation, changes occur which resemble those seen in natural aging of the aorta. It is plausible to assume that such a metabolic derangement in the vessel wall will make these vessels more vulnerable to additional stresses.
Experimental and Molecular Pathology
Volume 28, Issue 3, June 1978, Pages 279-289
Volume 28, Issue 3, June 1978, Pages 279-289
Friday, May 13, 2011
a significant impairment of the heart rate to workload relationship was consistently observed following sympathectomy
Several reports also demonstrate significantly lower heart rate increases during exercise in subjects who have undergone bilateral ISS [9–12] compared to pre-surgical levels. In spite of this high occurrence, recent reviews on the usual collateral effects of thoracic sympathectomy still do not include these possible cardiac consequences [6].
The aim of the present prospective study was to confirm that a significant impairment of the heart rate to workload relationship was consistently observed following unilateral and/or bilateral surgery.
Eur J Cardiothorac Surg 2001;20:1095-1100
http://ejcts.ctsnetjourna...i/content/full/20/6/1095
The aim of the present prospective study was to confirm that a significant impairment of the heart rate to workload relationship was consistently observed following unilateral and/or bilateral surgery.
Eur J Cardiothorac Surg 2001;20:1095-1100
http://ejcts.ctsnetjourna...i/content/full/20/6/1095
Thursday, May 12, 2011
slowing of the heart rate usually occurs on the second to fourth day after sympathectomy
The rate fell to a level between 40 and 6o per minute, the maximal slowing usually occurring on the second to fourth day after operation. Consistent slowing of the rate was not observed after a unilateral thoracic sympathectomy of either side. While there was some recovery from the maximum brady-
cardia with the passage of time in most patients, relatively slow resting cardiac rates and failure of tachycardia to develop with postural hypotension or exercise persisted in all patients.
Skoog's12 work has shown that there are marked differences in the number and precise location of the accessory ganglion cells in the cervical region in different patients and on the two sides in the same patient.
Even when a single midthoracic paravertebral ganglion is left in place in an otherwise total sympathectomy the thoracic dermatome supplied by the ganglion appears for several days or weeks to be sympathectomized also. Then, sweating begins to appear, and it increases gradually in amount until the skin of that dermatome may be dripping. This phenomenon more than any other meets the
objection of those who maintain that if residual pathways do exist, the evidence of their presence should be manifest immediately after operation.
Annals of Surgery, 1949 October
Volume 130 Number 4
cardia with the passage of time in most patients, relatively slow resting cardiac rates and failure of tachycardia to develop with postural hypotension or exercise persisted in all patients.
Skoog's12 work has shown that there are marked differences in the number and precise location of the accessory ganglion cells in the cervical region in different patients and on the two sides in the same patient.
Even when a single midthoracic paravertebral ganglion is left in place in an otherwise total sympathectomy the thoracic dermatome supplied by the ganglion appears for several days or weeks to be sympathectomized also. Then, sweating begins to appear, and it increases gradually in amount until the skin of that dermatome may be dripping. This phenomenon more than any other meets the
objection of those who maintain that if residual pathways do exist, the evidence of their presence should be manifest immediately after operation.
Annals of Surgery, 1949 October
Volume 130 Number 4
Tuesday, May 3, 2011
sympathectomy must somehow quiet the contralateral spread of spinal cord hyperexcitability underlying mirror-image pain
Blocking sympathetic function, whether by surgical sympathectomy, systemic phentolamine, or systemic guanethidine, relieves partial nerve injury-induced neuropathic pain in laboratory animal models as well as humans (8, 35, 146, 239, 278). Indeed, sympathectomy does not just relieve pathological pain in the body region ipsilateral to the CRPS-initiating event; rather, it also relieves pain arising from anatomically impossible mirror-image sites, that is, the identical body region contralateral to the initiating event (278). Thus sympathectomy must somehow quiet the contralateral spread of spinal cord hyperexcitability underlying mirror-image pain.
Alterations in sympathetic fibers rapidly follow peripheral nerve injury. This occurs as sprouting of sympathetic fibers, creating aberrant communication pathways from the new sympathetic terminals to sensory neurons (35). Sympathetic sprouting has been documented in the region of peripheral terminal fields of sensory neurons (262), at the site of nerve trauma (57), and within the dorsal root ganglia (DRG) containing cell bodies of sensory neurons (248, 343). Each of these sites develops spontaneous activity and sensitivity for catecholamines and sympathetic activation (8, 53).
The clearest evidence that immune activation participates in sympathetic sprouting comes from studies of the DRG. DRG cells receive signals that peripheral nerve injury has occurred via retrograde axonal transport from the trauma site. These retrogradely transported signals trigger sympathetic nerve sprouting into DRG (205, 308). As a result of nerve damage-induced retrogradely transported signals, glial cells within the DRG (called satellite cells) proliferate (248) and become activated (343); macrophages are recruited to the DRG as well (63, 176). In turn, the activated satellite glial cells (and, presumably, the macrophages) release proinflammatory cytokines and a variety of growth factors into the extracellular fluid of the DRG (206, 246 –248, 258, 277, 308, 358). These substances stimulate and direct the growth of sympathetic fibers, which form basket-like terminals around the satellite cells that, in turn, surround neuronal cell bodies (247, 248, 343).
Until recently, the sympathetic sprouting, rather than the glial (satellite cell) activation, has attracted the attention of pain researchers. The satellite cells were ignored as they were thought to be irrelevant to the creation of exaggerated pain states. However, it may be speculated that the satellite cells, rather than the sympathetic sprouts, have the most impact on pain.
Physiol Rev • VOL 82 • OCTOBER 2002 • www.prv.org
Beyond Neurons: Evidence That Immune and Glial Cells
Contribute to Pathological Pain States
LINDA R. WATKINS AND STEVEN F. MAIER
Department of Psychology and the Center for Neuroscience,
University of Colorado at Boulder, Boulder, Colorado
Monday, May 2, 2011
Chronic pain can occur after peripheral nerve injury, infection, or inflammation
Chronic pain can occur after peripheral nerve injury, infection, or inflammation. Under such neuropathic pain conditions, sensory processing in the affected body region becomes grossly abnormal. Despite decades of research, currently available drugs largely fail to control such pain. This review explores the possibility that the reason for this failure lies in the fact that such drugs were designed to target neurons rather than immune or glial cells. It describes how immune cells are a natural and inextricable part of skin, peripheral nerves, dorsal root ganglia, and spinal cord. It then examines how immune and glial activation may participate in the etiology and symptomatology of diverse pathological pain states in both humans and laboratory animals. Of the variety of substances released by activated immune and glial cells,
proinflammatory cytokines (tumor necrosis factor, interleukin-1, interleukin-6) appear to be of special importance in the creation of peripheral nerve and neuronal hyperexcitability.
Although this review focuses on immune modulation of pain, the implications are pervasive. Indeed, all nerves and neurons regardless of modality or function are likely affected by immune and glial activation in the ways described for pain.
Physiol Rev 82: 981–1011, 2002; 10.1152/physrev.00011.2002.
Saturday, April 23, 2011
Inflammation after a spinal cord injury (SCI) is nonresolving
Inflammation after a spinal cord injury (SCI) is nonresolving, and can be characterized by quantification of lymphocytes using resolution indexes (Ri) and resolution plateaus (Rp), according to an experimental study published online March 22 in Brain Pathology.
Harald Prüss, M.D.,
http://www.mdnews.com/news/hd/2011_16/hd_651416
Harald Prüss, M.D.,
http://www.mdnews.com/news/hd/2011_16/hd_651416
Friday, April 22, 2011
cervical sympathectomy works systemically through hypothalamus endocrine system
Background: To investigate the general action of stellate ganglion block (SGB), we examined the effects of heat stimulation and cold stress on the behavior and stress hormone of the bilateral cervical sympathectomy rats as a long-term and repeated SGB model. Methods: Wistar's male rats were divided into three groups: control (C), sham operation (S) and sympathectomy (Sx) groups. After 2 weeks, two experiments were done. One was measurement of escape response time from the heat stimulus and the other was hormone measurement. Serum adreno-corticotropic hormone (ACTH), .ALPHA.-melanocyte stimulating hormone (.ALPHA.-MSH) and .BETA.-endorphine (.BETA.-END) levels were measured assigning 3 groups to 2 subgroups with and without cold stress. Results: Escape response time was significantly extended in the Sx group. ACTH in the Sx group was significantly higher than in other groups, but changes of ACTH by cold stress were similar in 3 groups. In the Sx group .ALPHA.-MSH was hardly changed by cold stress while .ALPHA.-MSH was significantly decreased in the S group. Changes of .BETA.-END by cold stress were similar in the S and Sx groups. Conclusions: These results suggest that SGB works systemically through hypothalamus endocrine system and affects stress hormone differently. (author abst.)
http://sciencelinks.jp/j-east/article/200402/000020040204A0020288.php
Unilateral cervical sympathectomy resulted in a moderate and short decrease in milk secretion
the average amount of milk given by operated animals 10 days after operation being 76-3% of the initial level. Total cervical sympathectomy (the 2nd operation was performed 1 month later) caused a much greater and more prolonged decrease in milk secretion, 59.7% of the initial level being secreted during the 10 days after operation. A gradual increase in milk secretion was observed after the operation and this increase was more gradual after total sympathectomy than after partial sympathectomy. Denervation of the thyroid and parathyroids did not decrease milk secretion. Section of the pituitary stalk in 6 goats, which included complete section (2 goats), complete section with scar tissue at the site of section and considerable damage to the median eminence of the tuber einereum (1 goat) and incomplete section (3 goats) was performed. Milk ejection disappeared completely for 7-11 days in the goats with complete section and remained defective for some weeks after, but was still effective in those where the infundibular stem and part of the glandular portion of the pituitary stalk was still intact. Milk secretion was 28.9% of the initial level in the goats with complete section and 12.9% in the goat with the scar tissue whereas it was 40.5 and 55.7% in the incompletely sectioned and control operated goats. (See also D.S.A. 21 [3081].) D.E.E.
Monday, April 18, 2011
adult neurogenesis may contribute to the functioning, and phyio- and pathology of the CNS, particularly to the etiology of neurological diseases and disorders
Neuroinflammation is a process in which the brain responds to infections, diseases and injuries [1, 2]. Neuroinflammation involve two types of immune cells: lymphocytes, monocytes and macrophages of the hematopoietic system, and microglial cells of the CNS [3, 4]. Neuroinflammation disrupts the blood-brain barrier (BBB), allowing cells from the hematopoietic system to leave the blood stream and come in contact to the injury site [5]. The immune cells respond to injuries by eliminating debris and, synthesizing and releasing a host of powerful regulatory substances, like the complements, cytokines, chemokines, glutamate, interleukins, nitric oxide, reactive oxygen species and transforming growth factors [6-10]. The substances have both beneficial and harmful effects on the cellular environment, creating further damages [11] (fig. 1). Mature astrocytes are also activated following injury to the CNS [12, 13].
Chronic inflammation during depressive episodes could predispose depressive patients to neurodegenerative diseases, later in life [29].
http://www.medsci.org/v05p0127.htm
Chronic inflammation during depressive episodes could predispose depressive patients to neurodegenerative diseases, later in life [29].
http://www.medsci.org/v05p0127.htm
Tuesday, April 12, 2011
The cerebral vessels became hypersensitive to epinephrine after cervical sympathectomy
The cerebral vessels became hypersensitive to epinephrine after cervical sympathectomy.
HERTZMAN, A. B., AND DILLON, J. B.
Annual Review of Physiology
Vol. 4: 187-214 (Volume publication date March 1942)
HERTZMAN, A. B., AND DILLON, J. B.
Annual Review of Physiology
Vol. 4: 187-214 (Volume publication date March 1942)
Changes in the cerebral capillary bed following cervical sympathectomy
Arch. Neurol. and Psychiat., 1929, 21, 1102.Tracy J. PutnamThe Cerebral Circulation: Some New Points in its Anatomy, Physiology and Pathology
J Neurol Psychopathol, Jan 1937; s1-17: 193 - 212.
J Neurol Psychopathol, Jan 1937; s1-17: 193 - 212.
Tuesday, April 5, 2011
decreased brain metabolism, rather than an increased intracranial pressure, is the cause of decreased cerebral blood flow after superior cervical sympathetic ganglionectomy
"The reduced brain metabolism and consequently reduced cerebral perfusion in the late
postsympathectomy period could account for reduction in CSF production (Bering3)."
"In support of the above statement we mention that on the late postsympathectomy (11 to 24 months) group of dogs besides the lowered CBF
(31.36 ml/100 gm brain weight/minute) and MCP (79.3 mm NS) also a lowered MVP (46.5 mm NS) was found. These data indicate that cervicalsympathectomy has a profound and intricate effect on the dynamics of cerebrovascular fluids and probably, in the background of all observedphenomena, a decreased cerebral metabolism as a sympathectomy effect is the underlying cause. Correspondingly the cerebral metabolic rate ofoxygen (CMR O2) decreased to 2.94 and 2.43 ml of O2/IOO gm brain weight/ minute in the sympathectomized groups."
"Decreased brain metabolism, rather than an increased intracranial pressure, is the cause of decreased cerebral blood flow after superior
cervical sympathetic ganglionectomy."
http://archsurg.ama-assn.org/cgi/content/summary/90/3/418
Wednesday, March 30, 2011
Sympathectomy leading to an extracranial steal phenomenon
J Igloffstein and R Laas
J Neurol Neurosurg Psychiatry. 1983 August; 46(8): 768–773.
Unilateral cerebral infarcts were produced in the rat by ligation of one common carotid artery and subsequent exposure to carbon monoxide. The incidence and extension of brain infarcts was increased in animals with additional ipsilateral cervical preganglionic sympathectomy.Sympathectomy did not affect markedly the respiration and systemic circulation. The effect of sympathectomy was attributed to a cutaneous vasodilation, leading to an extracranial steal phenomenon.
J Neurol Neurosurg Psychiatry. 1983 August; 46(8): 768–773.
Unilateral cerebral infarcts were produced in the rat by ligation of one common carotid artery and subsequent exposure to carbon monoxide. The incidence and extension of brain infarcts was increased in animals with additional ipsilateral cervical preganglionic sympathectomy.Sympathectomy did not affect markedly the respiration and systemic circulation. The effect of sympathectomy was attributed to a cutaneous vasodilation, leading to an extracranial steal phenomenon.
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