sympathectomy leads to fluctuation of vasoconstriction alternated with vasodilation in an unstable fashion. Following sympathectomy the involved extremity shows regional hyper- and hypothermia

'To quote Nashold, referring to sympathectomy, "Ill- advised surgery may tend to magnify the entire symptom complex"(38). Sympathectomy is aimed at achieving vasodilation. The neurovascular instability (vacillation and instability of vasoconstrictive function), leads to fluctuation of vasoconstriction alternated with vasodilation in an unstable fashion (39). Following sympathectomy the involved extremity shows regional hyper - and hypothermia in contrast, the blood flow and skin temperature on the non- sympathectomized side are significantly lower after exposure to a cold environment (39). This phenomenon may explain the reason for spread of CRPS. In the first four weeks after sympathectomy, the Laser Doppler flow study shows an increased of blood flow and hyperthermia in the extremity (40). Then, after four weeks, the skin temperature and vascular perfusion slowly decrease and a high amplitude vasomotor constriction develops reversing any beneficial effect of surgery (39). According to Bonica , "about a dozen patients with reflex sympathetic dystrophy (RSD) in whom I have carried out preoperative diagnostic sympathetic block with complete pain relief, sympathectomy produced either partial or no relief (40)' Chronic Pain: Reflex Sympathetic Dystrophy : Prevention and ManagementHooshang HooshmandCRC PressINC, 1993 - Medical - 202 pages Eur J Appl Physiol. 2004 Oct;93(1-2):245-51. Epub 2004 Aug 25. Infrared thermography for examination of skin temperature in the dorsal hand of office workers.Gold JE1, Cherniack M, Buchholz B. Author information 1Department of Work Environment, University of Massachusetts Lowell, 1 University Avenue, Lowell, MA 01854, USA. Judith_Gold@uml.edu Reduced blood flow may contribute to the pathophysiology of upper extremity musculoskeletal disorders (UEMSD), such as tendinitis and carpal tunnel syndrome. The study objective was to characterize potential differences in cutaneous temperature, among three groups of office workers assessed by dynamic thermography following a 9-min typing challenge: those with UEMSD, with ( n=6) or without ( n=10) cold hands exacerbated by keyboard use, and control subjects ( n=12). Temperature images of the metacarpal region of the dorsal hand were obtained 1 min before typing, and during three 2-min sample periods [0-2 min (early), 3-5 min (middle), and 8-10 min (late)] after typing. Mean temperature increased from baseline levels immediately after typing by a similar magnitude, 0.7 (0.3) degrees C in controls and 0.6 (0.2) degrees C in UEMSD cases without cold hands, but only by 0.1 (0.3) degrees C in those with cold hands. Using paired t-tests for within group comparisons of mean dorsal temperature between successive imaging periods, three patterns of temperature change were apparent during 10 min following typing. Controls further increased mean temperature by 0.1 degrees C ( t-test, P=0.001) at 3-5 min post-typing before a late temperature decline of -0.3 degrees C ( t-test, P=0.04), while cases without cold hands showed no change from initial post-typing mean temperature rise during middle or late periods. In contrast, subjects with keyboard-induced cold hands had no change from initial post-typing temperature until a decrease at the late period of -0.3 degrees C ( t-test, P=0.06). Infrared thermography appears to distinguish between the three groups of subjects, with keyboard-induced cold hand symptoms presumably due, at least partially, to reduced blood flow. http://www.ncbi.nlm.nih.gov/pubmed/15338221

bilateral ETS causes the suppression of cardiovascular response to exercise, patients that has been treated with ETS need to be observed during high-level exercise

CARDIOVASCULAR EFFECTS OF BILATERAL ENDOSCOPIC TRANSTHORACIC SYMPATHICOTOMY AT REST AND DURING EXERCISE IN PATIENTS WITH PALMAR HYPERHIDROSIS

AUTHORS: Kazushi Takaishi, MD, Etsuo Tabo, MD, Kazuo Nakanishi, MD, Masao Soutani, MD,PhD, Kyoji Tsuno, MD, Tatsuru Arai, MDAFFILIATION: Ehime University, Shigenobu, Japan.
INTRODUCTION: Palmar hyperhidrosis is characterized by an overactivity of the sympathetic fibers passing through T2 and T3 ganglia. Although endoscopic transthoracic sympathicotomy (ETS) is an effective treatment for palmar hyperhidrosis, the partial cardiac denervation that follows may cause impairment of cardiovascular function at rest and during exercise. The purpose of this study was to compare the cardiovascular response to exercise between patients with palmar hyperhidrosis and a normal control population, and to examine the effects of ETS on cardiovascular response in patients with palmar hyperhidrosis.
METHODS: After institutional approval and informed consent, 16 patients with palmar hyperhidrosis undergoing bilateral T2- T4 ETS and 10 healthy volunteers were studied. First, before ETS administration, heart rate (HR), blood pressure (BP), and serum catecholamine (SC) at rest were measured in the patient group and in normal subjects. Then, changes in HR, BP and SC as a result of isometric handgrip exercise (IHE) were measured in both groups. Finally, HR and BP at rest, changes in HR and BP as a result of general exercise (GE), and changes in HR, BP and SC as a result of IHE were measured in the patient group both one day before and one day after ETS was administered.RESULTS: Although there was no significant difference in HR and BP at rest between the patient group before ETS and normal subjects, the value of serum adrenaline in the patient group (0.6 ng/ml) was significantly lower than that in normal subjects (2.6 ng/ml, p<0.01). Changes in HR, BP and SC to IHE were similar in both groups before ETS. HR and BP at rest, and changes in HR and BP as a result of GE and IHE were significantly decreased after ETS (p<0.05).

DISCUSSION: HR and BP at rest and cardiovascular response to exercise were similar in patients with palmar hyperhidrosis before ETS and in the normal control population. Therefore, we consider that patients with palmar hyperhidrosis have no overactivity of the sympathetic nerve. However, because bilateral ETS causes the suppression of cardiovascular response to exercise, patients that has been treated with ETS need to be observed during high-level exercise.

K Takaishi, E Tabo, K Nakanishi, M Soutani, K Tsuno, T Arai:
Cardiovascular effects of bilateral endoscopic transthoracic sympathicotomy at rest and during exercise in patients with palmar hyperhidrosis.
International Anesthesia Research Society
The 74th Clinical and Scientific Congress 2000

Snipping the verve may stop 'flight-or-fight' stress response

What do sweaty palms and abnormal heart rhythms have in common? Both can be initiated by the nervous system during an adrenaline-driven "flight-or-fight" stress reaction, when the body senses danger.

Hyperhidrosis, an abnormal flight-or-fight response of the sympathetic nervous system that causes excessively sweaty palms may also contribute to problems like dangerous irregular rhythms from the lower chambers of the heart, known as ventricular arrhythmias.

UCLA cardiologists have now found that surgery to snip nerves associated with the sympathetic nervous system on both the left and right sides of the chest may be helpful in stopping dangerous, incessant ventricular arrhythmias — known as an "electrical storm" — when other treatment methods have failed. This same type of surgery has been used for years to alleviate hyperhidrosis.

The UCLA team's findings are reported in the Dec. 27–Jan. 3 issue of the Journal of the American College of Cardiology. The study is one of the first to assess the impact of bilateral cardiac sympathetic denervation (BCSD), surgery on both sides of the heart, to control arrhythmias. The research builds on previous work at UCLA in which a similar procedure was performed only on the left side. But for some patients to obtain relief, the researchers said, it must be done bilaterally. 

http://newsroom.ucla.edu/releases/snipping-key-nerves-may-help-life-220281 

5 (11%) thermoregulation difficulties, 4 (9%) a sensation of left arm paresthesia, and 3 (7%) sympathetic flight/fright response loss

Patients with LQTS (N=40) and catecholaminergic polymorphic ventricular tachycardia (N=7) underwent video-assisted thoracoscopic left cardiac sympathetic denervation, with a median follow-up of 29 months (range, 1-67 months). Clinical records were reviewed; 44 patients completed a telephone survey. Of 47 patients (53%), 25 were preoperatively symptomatic (15 syncope, 7 near-drowning, and 3 resuscitated sudden death). Indications for left cardiac sympathetic denervation included β-blocker intolerance (15; 32%) or nonadherence (10; 21%) and disease factors (18; 38%; catecholaminergic polymorphic ventricular tachycardia [6], near-drowning [2], exertional syncope [1], symptoms on therapy [2], LQT3 [1], QTc>520 ms [6]). Other indications were competitive sports participation (2), family history of sudden death (1), and other (1). Median QTc did not change among patients with LQTS (461±60 to 476±54 ms; P=0.49). Side effects were reported by 42 of 44 (95%). Twenty-nine patients (66%) reported dryness on left side, 26 (59%) a Harlequin-type (unilateral) facial flush, 24 (55%) contralateral hyperhidrosis, 17 (39%) differential hand temperatures, 5 (11%) permanent and 4 (9%) transient ptosis, 5 (11%) thermoregulation difficulties, 4 (9%) a sensation of left arm paresthesia, and 3 (7%) sympathetic flight/fright response loss. 

Circ Arrhythm Electrophysiol. 2015 Oct;8(5):1151-8. doi: 10.1161/CIRCEP.115.003159. Epub 2015 Jul 29.

Physical and Psychological Consequences of Left Cardiac Sympathetic Denervation in Long-QT Syndrome and Catecholaminergic Polymorphic Ventricular Tachycardia.

http://www.ncbi.nlm.nih.gov/pubmed/26224781

Endoscopic view of the right hemithorax:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2749196/figure/F0003/

Sympathectomy - a neurocardiologic disorder

Bilateral thoracic sympathectomies or sympathotomies are done for refractory palmar hyperhidrosis [85–87]. Iontophoresis, botulinum toxin injection, and glycopyrrolate cream are alternatives. Because sweating is mediated mainly by sympathetic cholinergic fibers, autonomic neurosurgery is usually effective; however, a variety of expected and unexpected consequences can result, including ectopic (e.g., plantar) hyperhidrosis, gustatory sweating, Horner syndrome, and decreased heart rate responses to exercise. The latter seems to be related to partial cardiac denervation [88]. Anecdotally, fatigue, altered mood, blunted emotion, and decreased ability to concentrate can develop after bilateral thoracic sympathectomies. 

β-Adrenoceptor blockers are a mainstay of treatment for CPVT. An automated defibrillator may have to be implanted. Treatment for CPVT also includes left sympathectomy. Such treatment leaves open the theoretical possibilities of denervation supersensitivity of cardiac adrenoceptors and compensatory activation of the adrenomedullary hormonal system; however, plasma levels of catecholamines have not been assessed in CPVT with or without therapeutic cardiac denervation.

Table 1. Neurocardiologic disorders that feature abnormal catecholaminergic function

Disorders where abnormal catecholaminergic function is etiologic Hypofunctional states without central neurodegeneration
Acute, primary
Neurocardiogenic syncope Spinal cord transection Acute pandysautonomia Sympathectomy
Acute, secondary
Drug-related (e.g., alcohol, tricyclic antidepressant, chemotherapy, opiate, barbiturates, benzodiazepines, sympatholytics, general anesthesia)
Seizures
Guillain–Barre syndrome Alcohol

Chronic, primary

Pure autonomic failure
Horner's syndrome
Familial dysautonomia
Carotid sinus syncope

Adie's syndrome Dopamine-β-hydroxylase deficiency
Sympathectomy 

http://onlinelibrary.wiley.com/doi/10.1111/j.1755-5922.2010.00244.x/full

https://archive.is/UMW1w

the clinical results of both surgical and neurolityc sympathectomy are uncertain

Blood diverted from muscle to skin after sympathectomy

 

However, the clinical results of both surgical and neurolityc sympathectomy are uncertain. Indeed these procedures lead to a redistribution of the blood flow in the lower limbs from the muscle to the skin, with a concomitant fall of the regional resistance, mainly in undamaged vessels. The blood flow will be diverted into this part of the vascular tree, so that a "stealing" of the blood flow may occur.

Vito A. Peduto, Giancarlo Boero, Antonio Marchi, Riccardo Tani

Bilateral extensive skin necrosis of the lower limbs following prolonged epidural blockade

Anaesthesia 1976; 31: 1068-75.