Chapter 193 - Sympathectomy

Question 1

first use of cervical sympathectomy

Answer 1

Hyperhidrosis Kotzareff 1920

Question 2

First use of sympathectomy for muscle spastic paralysis

Answer 2

1924 Hunter no benefit but increased circulation in limb

Question 3

first lumbar sympathectomy

Answer 3

1924 Diez for thromboangiitis obliterans

Question 4

First sympathectomy for Raynaud

Answer 4

Leriche 1924

Question 5

Sympathetic route

Answer 5

First neuron: cell body in sudomotor and vasomotor centre (hypothalamus) –> axon along dorsal longitudinal and spinovestibular fascicles Second neuron (preganglionic neuron): body in intermediolateral nucleus of spinal gray matter between T1 and T2 –> axons exit medulla through ventral root of spinal nerve to paravertebral ganglion Third neuron (post-ganglionic neuron): axon leaves sympathetic chain through grey communicating branch into spinal nerve –> periphery

Question 6

Three sympathetic ganglia in the neck

Answer 6

Superior cervical ganglion: fusion of first 4 at C2-3 Middle cervical ganglion: C6 Inferior cervical ganglion: fusion with first thoracic ganglion = cervicothoracic/stellate ganglion anterior to head of first rib

Question 7

Thoracic sympathetic ganglia position

Answer 7

anterior to transverse process covered by parietal pleura

Question 8

Thoracic sympathetic ganglia types

Answer 8

First one is fused with inferior cervical ganglion last fused with first lumbar ganglion the rest fused together

Question 9

Splanchnic nerve origin

Answer 9

Preganglionic fibers from T5-T12 medullary segments Forms: 1) greater 2) lesser 3) least splanchnic nerves

Question 10

Sympathetic innervation of upper limbs

Answer 10

2nd to 8th thoracic medullary segment (most below 4th) –> paravertebral sympathetic chain –> ascending pathway –> synapse in: 1) second thoracic ganglion 2) stellate ganglion 3) middle cervical ganglion

Question 11

Location of thoracic sympathetic trunk in relation to ribs

Answer 11

middle of intercostal spaces

Question 12

Sympathetic innervation of lower limbs

Answer 12

12th thoracic to 2nd lumbar medullar segment –> white rami communicantes –> lumbar and sacral ganglia: lumbar plexus come from 1st to 3rd lumbar ganglia sacral plexus from 4th lumbar ganglia + sacral ganglia

Question 13

Lowest rami comunicantes

Answer 13

None under 2nd lumbar ganglion

Question 14

Horner syndrome

Answer 14

1) enophthalmos 2) myosis 3) ptosis 4) anhidrosis

Question 15

Innervation to the smooth muscles of the eye

Answer 15

Sympathetic preganglionic fibers from anterior roots of G1 and G2 Synapse in superior cervical ganglion Ocular-pupillary apparatus through carotid plexus

Question 16

Sympathetic innervation of head and neck

Answer 16

from 1st to 5th thoracic medullary segments mostly G2 –> Stellate ganglion

Question 17

Number of paravertebral ganglia at each spinal region

Answer 17

Cervical 3 Thoracic 12 Lumbar 4 Sacral 4-5

Question 18

Sympathetic innervation of the heart

Answer 18

superior medial and inferior heart nerves from 3 cervical ganglia 6-7 thoracic paravertebral ganglia

Question 19

Sympathetic nerve fibers that innervate blood vessels

Answer 19

Adrenergic fibers

Question 20

Sympathetic nerve fibers that innervate sweat glands

Answer 20

Cholinergic fibers

Question 21

Innervation of eccrine sweat glands

Answer 21

nonmyelinic C fibers of sympathetic nerves Acetylcholine as mediator

Question 22

Cannon’s law

Answer 22

When one unit in a series of efferent neurons is destroyed, there is increased irritability to chemical agents effect is greater in the part that was denervated exception is sweat glands where post-ganglionic denervation stops sweating

Question 23

Types of sweating pathways

Answer 23

1) emotional sweat - cortical center 2) thermal sudoresis - hypothalamic center 3) gustatory sudoresis - medullary nuclei 4) spinal sweating - intermediate-lateral region of spinal cord 5) nonsensory sweating/pesspiration - always occurs via glands and water loss via epidermis

Question 24

Indication for cervicothoracic sympathectomy

Answer 24

1) essential hyperhidrosis 2) critical hand ischemia 3) CRPS 4) refractory long QT 5) Raynaud syndrome

Question 25

Hyperhidrosis prevalence

Answer 25

3%

Question 26

Family history in hyperhidrosis

Answer 26

13-57%

Question 27

Treatments for hyperhidrosis

Answer 27

1) oxybutynin 2) botox injection 3) glycopyrrolate 4) sympathectomy

Question 28

Complication of sympathectomy for hyerphidrosis

Answer 28

compensatory hyperhidrosis

Question 29

Indication for sympathectomy in hand ischemia

Answer 29

Thromboangiitis obliterans distal artery obstruction poor indication since other management strategies are better

Question 30

Long QT complication

Answer 30

1) tachyarrhythmia 2) syncope 3) sudden death

Question 31

Treatment for Long QT

Answer 31

1) beta blocker (work in 75-80%) 2) sympathectomy if others fail (20-25% pts will need it)

Question 32

Open exposure for cervicothoracic sympathectomy

Answer 32

1) paravertebral route (neurosurgery): extensive dissection, long recovery 2) transthoracic axillary approach: superior exposure, lower risk of Horner, better cosmetic; higher postsympathectic neuralgia long recovery 3) Supraclavicular approach: extrapleural access allowing bilateral approach, minimal scar, show recovery; high Horner syndrome due to manipulation of stellate ganglion

Question 33

Gold standard for sympathectomy

Answer 33

Video-assisted thoracoscopic sympathectomy

Question 34

VATS key points

Answer 34

1) double lumen endotracheal GA 2) dorsal decubitus with 45 degree trunk raise 3) arms at 90 degree abduction 4) first incision: anterior axillary line 4th or 5th intercostal space 5) second incision: mid axillary line, 2nd or 3rd intercostal space 6) 5.5 mm trochars

Question 35

Appearance of the sympathetic chain in VATS

Answer 35

1) whitish 2) longitudinal 3) multinodular cord 4) slight prominence 5) lateroposterio region of thoracic vertebrae

Question 36

Ways to ligate sympathetic chain

Answer 36

Electrocautery clips

Question 37

conditions that make VATS more difficult

Answer 37

1) adhesions 3-7% 2) azygos lobe at apex of lung

Question 38

Contraindication to VATS

Answer 38

1) lung infection with pleural effusion 2) dense adhesions (TB) 3) previous thoracic surgery 4) previous radiation 5) sinus bradycardia 6) extreme obesity

Question 39

Denervation levels for different indications

Answer 39

TABLE 193.1

Question 40

Palmer and axillary hyperhidrosis and different ganglia effects

Answer 40

G2 = compensatory hyperhidrosis risk G3 = dry hands G4 = some sweating but much improved - current therapeutic goal

Question 41

Success of treating hyperhidrosis with sympathectomy

Answer 41

Palmar 96%+ Axillary 63%+ Craniofacial 87%+ overall 90% satisfaction at 5 years Not as good for plantar

Question 42

Transitory occurrence of sweating rate

Answer 42

13% lasting 36 hours

Question 43

Complication of sympathectomy

Answer 43

1) gustatory sudoresis 6-32% 2) compensatory hyperhidrosis (1-4% severe)

Question 44

Factors associated with higher risk of compensatory hyperhidrosis

Answer 44

1) higher resection of sympathetic chain 2) higher BMI > 25 3) older adults have harder time tolerating (children don’t mind)

Question 45

Complications of VATS

Answer 45

1) compensatory sweating 70-100% 2) segmental atelectasis 1-5% 3) pneumothorax 1-5% 4) subcutaneous emphysema 1-2% Rare < 1% 1) horner 2) hemothorax 3) pleural effusion 4) injury to vagus, phrenic 5) injury to subclavian artery, vein 6) chylothorax