Sympathectomy - a surgically induced neuropathy

"Vascular and neural diseases are closely related and intertwined. Blood vessels depend on normal nerve function, and nerves depend on adequate blood flow. The first pathological change in the microvasculature is vasoconstriction. As the disease progresses, neuronal dysfunction correlates closely with the development of vascular abnormalities, such as capillary basement membrane thickening and endothelial hyperplasia, which contribute to diminished oxygen tension and hypoxia."

http://en.wikipedia.org/wiki/Diabetic_neuropathy

Sympathectomy results in vascular abnormalities, loss of vasoconstriction, capillary basement thickening and endothelial hyperplasia...

oedema associated with the interruption of preganglionic sympathetic tract

Swelling and oedema is often observed in patients with Raynaud's disease or causalgia after acute interruption of post-ganglionic sympathetic fibres such as a wide-spread sympathectomy. Complete sympathetic 

block dilates vein and capillary and increases peripheral pooling, which raises hydrostatic the shins and feet (fig 2), constipation and 

abdominal distention, and dysuria were observed. Oedema was not noted in the 

hands or face. 

 There were no signs or abnormal laboratory data suggesting heart failure, renal failure, liver dysfunction, thyroid dysfunction or local inflammation. Venography of the left leg did not show obstruction in the deep veins. 

 We showed that the preganglionic sympathetic tract in the spinal cord was often 

disturbed in patients with multiple sclerosis with myelopathy.' Most patients with com- 

plete transection of the spinal cord due to injury showed swelling of the lower limbs or 

oedema, but they gradually subsided within several months even without restoration of 

somatic function. Probably some compensatory mechanism improves the hydrostatic 

condition in the chronic stage and explains why oedema is not noted in patients with 

chronic autonomic failure syndrome.

http://www.ncbi.nlm.nih.g...f/jnnpsyc00488-0062b.pdf

The indications for neurolytic or surgical sympathectomy are uncertain

The indications for neurolytic or surgical sympathectomy are uncertain. There is no clear correlation between the degree or duration of pain relief and the actual period of sympathetic blockade and the same patient may show variable responses on different occasionsv (Loh et al 1980). Some patients demonstrate unexpected responses such as contralateral or delayed blocks and some are made worse (Purcell-Jones &Justins 1988, Evans et al 1980, Kleiman 1954)

http://www.springerlink.com/content/7013w45630522h6k/

Sympathectomy causes depigmentation of the skin

In this article, 2 patients were submitted to video-assisted thoracoscopic sympathectomy, and after approximately 8 months they noticed depigmentation of the region corresponding to the blockage of sympathetic stimulus. This fact could be explained by the possible effect of the nervous system on the melanocytes of human skin. 

Sympathectomy? 

Skin Depigmentation: Could it Be a Complication Caused by Thoracic 

 2009;88:42-43 Ann Thorac Surg 

http://ats.ctsnetjournals.org/cgi/reprint/88/4/e42.pdf 

Post-sympathectomy neuralgia

Post-sympathectomy neuralgia is proposed here to be a complex neuropathic and central deafferentation/reafferentation syndrome dependent on: (a) the transection, during sympathectomy, of paraspinal somatic and visceral afferent axons within the sympathetic trunk; (b) the subsequent cell death of many of the axotomized afferent neurons, resulting in central deafferentation; and (c) the persistent sensitization of spinal nociceptive neurons by painful conditions present prior to sympathectomy. Viscerosomatic convergence, collateral sprouting of afferents, and mechanisms associated with sympathetically maintained pain are all proposed to be important to the development of the syndrome.

Pain. 1996 Jan;64(1):1-9
http://www.ncbi.nlm.nih.gov/pubmed/8867242?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum

Neuroma following Sympathectomy

The authors conclude recomemnding the application of clips and if the syndrome nevertheless appears novocaine infiltration of the upper end of the sympathetic chain. The authors are convinced that the theory of Hermann and Cooley about neuroma formation at the ends of the sympathetic chain after resection of a segment is true.
http://www.revangiol.com/sec/resumen.php?or=web&i=e&id=227082.
Traumatic neuroma follows different forms of nerve injury (often as a result of surgery). They occur at the end of injured nerve fibres as a form of ineffective, unregulated nerve regeneration; it occurs most commonly near a scar, either superficially (skin, subcutaneous fat) or deep (e.g., after acholecystectomy). They are often very painful. It is also known as "pseudoneuroma".

Autonomic Neuropathy Differential Diagnoses

Differentials 

Aromatic L-amino acid decarboxylase deficiency 

Autonomic dysreflexia syndrome in spinal injuries. 

Dopamine beta-hydroxylase deficiency 

Multiple System Atrophy 

Parkinson Disease 

Parkinson-Plus Syndromes 

Progressive Supranuclear Palsy 

Pure Autonomic Failure 

Surgical sympathectomy 

Syphilis (tabes dorsalis) 

Vagotomy 

http://emedicine.medscape.com/article/1173756-differential

A depression in the heart rate and decrease in response to stress is expected to some degree in all patients after sympathectomy

A depression in the heart rate with resultant drop in the heart rate product and decrease in response to stress is expected to some degree in all patients. Some series have described this finding in most patients, whereas others report at least a 10% drop in heart rate in all patients. This is a possible major cause for postoperative dysfunction and should be cautiously sought after. Patients with resting heart rate that is below 50 to 60 beats/min should undergo electrocardiography. It is recommended that if the heart rate is low on a subsequent electrocardiogram as well, that a tilt test should be performed to exclude patients in whom there is an inordinately high risk of postoperative bradycardia.

In conclusion, thoracoscopic sympathectomy can be done as an outpatient procedure safely and efficiently. Debate continues about the correct transection levels, but at this time there is a consensus that division or clipping is equal to resection. Although the procedure has several severe side effects, they are rare. The predominant complication remains compensatory sweating, which may occur regardless of the level transected or the indication. Future clinical trials should compare some of the different techniques to achieve a global consensus of the surgical approach.

http://ats.ctsnetjournals.org/cgi/content/full/85/2/S764

The biology and control of surface overhealing

Lesions of “surface overhealing” include keloid, hypertrophic scar, and burn scar. All are characterized by overabundant collagen deposition. The biology of these lesions is reviewed, suggesting that abnormal collagen metabolism results from alterations in the inflammatory/immune response. Practical and theoretical treatment plans are outlined based on methods that alter collagen metabolism, the inflammatory/immune system or rely on physical alterations (surgery, pressure).

http://www.springerlink.com/content/3g2mr5r32m438125/

the PPG signal and the VLF fluctuations of the PPG parameters enable the assessment of the change in sympathetic nervous system activity after sympahtectomy

The photoplethysmographic (PPG) signal, which measures cardiac-induced changes in tissue blood volume by light transmission measurements, shows spontaneous fluctuations. In this study, PPG was simultaneously measured in the right and left index fingers of 16 patients undergoing thoracic sympathectomy, and, from each PPG pulse, the amplitude of the pulse (AM) and its maximum (BL) were determined. The parameter AM/BL is proportional to the cardiac-induced blood volume increase, which depends on the arterial wall compliance. AM/BL increased after the thoracic sympathectomy treatment (for male patients, from 2.60±1.49% to 4.81±1.21%), as sympathetic denervation decreases arterial tonus in skin. The very low-frequency (VLF) fluctuations of BL or AM showed high correlation (0.90±0.11 and 0.92±0.07, respectively) between the right and left hands before the thoracic sympathectomy, and a significant decrease in the right-left correlation coefficient (to 0.54±0.22 and 0.76±0.20, respectively) after the operation. The standard deviation of the BL or AM VLF fluctuations also reduced after the treatment, indicating sympathetic mediation of the VLF PPG fluctuations. The study also shows that the analysis of the PPG signal and the VLF fluctuations of the PPG parameters enable the assessment of the change in sympathetic nervous system activity after thoracic sympathectomy.

http://www.springerlink.com/content/w7n21366239753l5/

regional sympathectomy leads to qualitative alterations in localized bone modeling and remodeling

Bone modeling and remodeling are highly regulated processes in the mammalian skeleton. The exact mechanism by which bone can be modeled at a local site with little or no effect at adjacent anatomic sites is unknown. Disruption of the control of modeling within the temporal bone may lead to various bone disease such as otosclerosis, osteogenesis imperfecta, Paget's disease of bone, fibrous dysplasia, or the erosion of bone associated with chronic otitis media. One possible mechanism for such delicate control may be related to the ubiquitous and rich sympathetic innervation of all periosteal surfaces. Previous studies have indicated that regional sympathectomy leads to qualitative alterations in localized bone modeling and remodeling. In this study, unilateral cervical sympathectomy resulted in significant increases in osteoclast surface and osteoclast number within the ipsilateral bulla of experimental animals. The mechanisms by which sympathectomy leads to increased local bone loss is unknown. Potential mechanisms include disinhibition of resorption, secondary to the elimination of periosteal sympathetics, as well as indirect vascular effects.

http://www.ncbi.nlm.nih.gov/pubmed/8723974

dysregulation of the immune system after sympathectomy

Haug and Heyeraas, 2005
 http://jdr.sagepub.com/content/85/6/488 

Depression of Endothelial Nitric Oxide Synthase but Increased Expression of Endothelin-1 Immunoreactivity in Rat Thoracic Aortic Endothelium Associated With Long-term, but Not Short-term Sympathectomy

Circulation Research. 1996;79:317-323

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.

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

sympathectomy results in an increased collagen content in the vascular 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

cervical sympathectomy resulted in a moderate and short decrease in milk secretion

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.
http://www.cabdirect.org/abstracts/19600402546.html;jsessionid=A943A1F56D5D120B419B65425A893BB0

sympathectomy induces several biochemical changes in skeletal muscle

It is concluded that sympathectomy induces several biochemical changes in skeletal muscle which constitute a change and increase in fast myosin light chain synthesis and a corresponding fibre type transformation.
Received 24 August 1987; accepted 26 October 1987

Clinical Physiology and Functional Imaging

"We have previously reported functional and histological studies in five beagle dogs with unilateral lumbar sympathectomy. Three months later, fatiguability in the gracilis muscles was increased on the denervated sides, and this was associated with an increase in the relative distribution of FT fibres. Biochemical studies now show that these changes were associated with an increase in cytosolic protein without change in DNA content; this is consistent with an increase in cell size. There was a reduction in the proportion of slow myosin light chain isoforms from 50 +/- 7 to 34 +/- 6%. Noradrenaline levels were increased on the denervated sides but this may reflect greater vascularity. Calcium content did not correlate with fibre type but there was a positive relation with both noradrenaline content (r = 0.73; P less than 0.05) and DNA content (r = 0.84; P less than 0.05). It is concluded that sympathectomy induces several biochemical changes in skeletal muscle which constitute a change and increase in fast myosin light chain synthesis and a corresponding fibre type transformation."
Journal: Clinical physiology (Oxford, England) (Clin Physiol), published in ENGLAND.
Reference: 1988-Apr; vol 8 (issue 2) : pp 181-91
Dates: Created 1988/06/08; Completed 1988/06/08; Revised 2004/11/17;
PMID: 3359751, status: MEDLINE (last retrieval date: 2/18/2009, IMS Date: )

Collagen types I and III mRNA were decreased respectively by 53% and 22% after sympathectomy

In the present study, we tested the hypothesis of the indirect (via the sympathetic nervous system (SNS)) and direct (via AT1 receptors) contributions of Angiotensin II (Ang II) on the synthesis of collagen types I and III in the left ventricle (LV) in vivo. Sympathectomy and blockade of the Ang II receptor AT1 were performed alone or in combination in normotensive rats. The mRNA and protein synthesis of collagen types I and III were examined by Q-RT-PCR and immunoblotting in the LV.

Collagen types I and III mRNA were decreased respectively by 53% and 22% after sympathectomy and only collagen type I mRNA was increased by 52% after AT1 receptor blockade. mRNA was not changed for collagen type I but was decreased by 25% for collagen type III after double treatment. Only collagen protein type III was decreased after sympathectomy by 12%, but collagen proteins were increased respectively for types I and III by 145% and 52% after AT1 receptor blockade and by 45% and 60% after double treatment. Deducted interpretations from our experimental approach suggest that Ang II stimulates indirectly (via SNS) and inhibits directly (via AT1 receptors) the collagen type I at transcriptional and protein levels. For collagen type III, it stimulates indirectly the transcription and inhibited directly the protein level. Therefore, the Ang II regulates collagen synthesis differently through indirect and direct pathways.

http://www.autonomicneuroscience.com/article/S1566-0702(09)00416-0/abstract

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

Conditions arising after Sympathectomy:

After stellate ganglion blockade: HORNER'S SYNDROME

• Drooping eyelid
• Constricted pupil (impaired vision in low light)
• Absent/reduced sweating one side of the face and head
• Redness of eyes
• Facial flushing

After regional sympathectomy: DUMPING SYNDROME:

• Rapid emptying of the stomach: lower end of small intestine fills too quickly
• Early dumping: nausea/vomiting/bloating/diarrhoea/shortness of breath
• Late dumping: 1-3 hours after eating: weakness/sweating/dizziness
• Both types may co-exist.

http://www.theaword.org/index.php?option=com_content&view=article&id=223:conditions-arising-after-sympathectomy&catid=84:the-sympathetic-nervous-system&Itemid=41