A brief summary on formation and functioning of Autonomic Nervous System, with a general idea on Stellate Ganglion Block.

1. The
Sympathetic
Nervous System
Organisation and Clinicals
Mod. Dr. Avanish Bhardwaj

2. Organization of The Nervous System
Central Nervous System Peripheral Nervous System
Sensory- Somatic Nervous
System
Autonomic Nervous System
Sympathetic Parasympathetic

3. The Autonomic Nervous System and
Visceral Sensory Neurons
 The Autonomic Nervous System
 It is responsible for monitoring conditions in the
internal environment and bringing about
appropriate changes in them.
 Innervates smooth muscle, cardiac muscle, and
glands
 Regulates visceral functions
 Heart rate, blood pressure, digestion, urination

4. The Autonomic Nervous System and Visceral
Sensory Neurons
Figure 1

5. Comparison of Autonomic and
Somatic Motor Systems
 Somatic motor
system
 One motor neuron
extends from the
CNS to skeletal
muscle
 Axons are well
myelinated, conduct
impulses rapidly
 Autonomic nervous
system
 Chain of two motor
neurons
 Preganglionic
neuron
 Postganglionic
neuron
 Conduction is slower
due to thinly or
unmyelinated axons

6. Autonomic and Somatic Motor
Systems

7. Divisions of the Autonomic Nervous
System
 Sympathetic and parasympathetic divisions
 Innervate mostly the same structures, but cause
opposite effects
 Sympathetic – “fight, flight, or fright”
 Activated during exercise, excitement, and
emergencies
 Parasympathetic – “rest and digest”
 Concerned with conserving energy

8. Anatomical Differences in Sympathetic
and Parasympathetic Divisions
 Issue from
different regions
of the CNS
 Sympathetic – also
called the
thoracolumbar
division
 Parasympathetic –
also called the
craniosacral division

9. Anatomical Differences in Sympathetic
and Parasympathetic Divisions
 Length of postganglionic fibers
 Sympathetic – long postganglionic fibers
 Parasympathetic – short postganglionic fibers
 Branching of axons
 Sympathetic axons – highly branched
 Influences many organs
 Parasympathetic axons – few branches
 Localized effect

10. Sympathetic System
 Sympathetic preganglionic neurons are
primarly located in intermediolateral nucleus
at the T1 to L2 levels of spinal cord
 Distribution of preganglionic fibers does not
follow dermatomal pattern of somatic nerves.

11. SPINAL SEGMENTS INNERVATION
T1 – T3 HEAD
T1 – T6 UPPER EXTREMITIES
THORACIC VISCERA
T5 – T11 ABDOMINAL VISCERA
T11 – L2 LOWER EXTREMITIES
PELVIC & PERINEAL ORGANS

12. Typical Organisation Of A Spinal Nerve

13.  Preganglionic sympathetic axons exit through
ventral roots and pass via white rami
communicantes on corresponding spinal nerve to
reach the paravertebral sympathetic chain
 Majority of them run rostrally or caudally along
the sympathetic chain and synapse on large
paravertebral ganglia.
 Remaining fibers pass through paravertebral
chain without synapsing and form splanchnic
nerves that innervate prevertebral ganglia &
adrenal glands

14. Sympathetic Pathways to Periphery
Figure 15.9

15. Sympathetic Trunk Ganglia
 Located on both sides of the vertebral column
 Linked by short nerves into sympathetic
trunks
 They are the primary relay stations for
preganglionic inputs
 They innervate all tissues and organs except
those in abdomen, pelvis and perineum
 Fusion of ganglia  fewer ganglia than spinal
nerves

16. Sympathetic Trunk Ganglia

17. Prevertebral Ganglia
 Unpaired, not segmentally arranged
 Occur only in abdomen and pelvis
 Lie anterior to the vertebral column
 Main ganglia
 Celiac, superior mesenteric, inferior mesenteric,
inferior hypogastric ganglia

19. Sympathetic Outflow
 Sympathetic preganglionic neurons –
organized into different functional units which
control specific targets –
 Muscle vasomotor
 Splanchnic vasomotor
 Skin vasoconstrictor
 Skin vasodilator
 Cardiomotor
 Visceromotor preganglionic neurons

20.  Sympathetically induced vasoconstriction of
skeletal muscle and splanchnic vessels is critical
to avoid orthostatic hypotension ( alpha 1 )
 Sympathetic outflow to skin blood vessels and
sweat glands is critical for thermoregulation –
 exposure to cold – skin vasoconstriction
piloerection ( alpha 1 )
 exposure to heat – sweating
skin vasodilatation ( M3 )

21. Organ
Parasympathetic Response
"Rest and Digest"
Sympathetic Response
"Fight or Flight"
Heart
(baroreceptor
reflex)
Decreased heart rate
Cardiac output decreases
Increased rate and strength of
contraction
Cardiac output increases
Lung Bronchioles Constriction Dilation
Liver Glycogen No effect
Glycogen breakdown
Blood glucose increases
Fat Tissue No effect
Breakdown of fat
Blood fatty acids increase
Basal Metabolism No effect Increases ~ 2X
Stomach
Increased secretion of HCl & digestive
enzymes & Increased motility
Decreased secretion
Decreased motility
Intestine
Increased secretion of HCl & digestive
enzymes & Increased motility
Decreased secretion
Decreased motility
Urinary bladder
Relaxes sphincter
Detrusor muscle contracts
Urination promoted
Constricts sphincter
Relaxes detrusor
Urination inhibited
Rectum
Relaxes sphincter
Contracts wall muscles
Defecation promoted
Constricts sphincter
Relaxes wall muscles
Defecation inhibited
Eye
Iris constricts
Adjusts for near vision
Iris dilates
Adjusts for far vision
Male Sex Organs Promotes erection Promotes ejaculation

22. The Role of the Adrenal Medulla in
the Sympathetic Division
 Major organ of the sympathetic nervous
system
 Secretes great quantities epinephrine (a little
norepinephrine)
 Stimulated to secrete by preganglionic
sympathetic fibers

23. The Adrenal Medulla

24. Neurotransmitters of Autonomic
Nervous System
 Neurotransmitter released by preganglionic
axons
 Acetylcholine for both branches (cholinergic)
 Neurotransmitter released by postganglionic
axons
 Sympathetic – most release norepinephrine
(adrenergic)
 Parasympathetic – release acetylcholine

25. How do we define neuron types in the
ANS?
C O
O
CH2 CH2 N
CH3
CH3
CH3
CH3
CH2 N
CH3
CH3
CH3
O
HO
H3C
N
CH3
N
HO
HO CH
OH
CH2 NH2
HO
HO CH
OH
CH2 NH
CH3
Parasympathetic
Sympathetic
Acetylcholine
Muscarine
Nicotine
Norepinephrine
(Noradrenaline)
Epinephrine
(Adrenaline)

26. Anatomical Differences in Sympathetic
and Parasympathetic Divisions

27. Anatomical Differences in Sympathetic
and Parasympathetic Divisions

28. Summary of sympathetic neurons
and synapses
Preganglionic neurons
 Short
 Synapse with postganglionic neurons near spinal cord
 Release acetylcholine (ACH) to activate nicotinic receptors on
postganglionic neurons
Postganglionic neurons
 Long
 Synapse on the target organ
 Release norepinephrine to activate adrenergic receptors on
target organs

29.  Sweat glands:
» Postganglionic neurons
involved with stress-related
excretion release
norepinephrine (“sweaty
palms”)
» Postganglionic neurons
involved with thermoregulation
release acetylcholine
Exceptions in the sympathetic nervous system:

30.  Kidneys:
» Postganglionic neurons to the
smooth muscle of the renal
vascular bed release dopamine
 Adrenal gland:
» Preganglionic neurons do not
synapse in the paraverterbral
sympathetic ganglion
» Preganglionic neurons synapse
directly on the adrenal gland,
release acetylcholine, and activate
nicotinic receptors on the adrenal
gland
» Adrenal glands release epinephrine
into systemic circulation
Exceptions in the sympathetic nervous system:

31. Stellate ganglion block
indications, procedure and
complications

32.  The stellate
ganglion (or cervicothoracic
ganglion or inferior cervical ganglion) is
a sympathetic ganglion formed by the
fusion of the inferior cervical
ganglion and the first
thoracic ganglion.
 It is located at the level of C7 (7th
cervical vertebrae), anterior to
the transverse process of C7, anterior to
the neck of the first rib, and just below the
subclavian artery.
Stellate ganglion

33. Anatomy
Anterior
The structures anterior to the
ganglion include the skin and
subcutaneous tissue, the
sternocleidomastoid and the
carotid sheath. The dome of the
lung lies anterior and inferior to
the ganglion

34.  Medial
The prevertebral fascia, vertebral body of
C7, oesophagus and thoracic duct lie
medially
 Posterior
Structures posterior to the ganglion include
the longus colli muscle, anterior scalene
muscle, vertebral artery, brachial plexus
sheath and neck of the first rib.
CONTINUED……

35. Chassaignac’s tubercle
This is the anterior tubercle
of the transverse process
of the sixth cervical
vertebra, which lies lateral
to and at a slightly higher
level than the posterior
tubercle, and against which
the carotid artery may be
compressed by the finger.

36.  Stellate Ganglion block is an injection of
local anaesthetic in the "sympathetic
nerve tissue" - the nerves which are a part
of Sympathetic Nervous System
 The injection consists of a local anaesthetic
(like lidocaine or bupivacaine). Epinephrine
(adrenaline) may be added to prolong the
effects of the injection
Stellate ganglion block

37.  A stellate ganglion block blocks the sympathetic
nerves that go to the arms, and, to some
degree, the sympathetic nerves that go to the
face.
 This may in turn reduce pain, swelling, colour
and sweating changes in the upper extremity
and may improve mobility.
 It is done as a part of the treatment of Reflex
Sympathetic Dystrophy (RSD), Sympathetic
Maintained Pain, Complex Regional Pain
Syndrome and Herpes Zoster (shingles)
involving an arm or the head and face.
Purpose of block

38.  Pain syndromes
 Complex regional pain syndrome type I and II
 Refractory angina
 Phantom limb pain
 Herpes zoster
 Shoulder/hand syndrome
 Angina
Indications

39.  Vascular insufficiency
 Raynaud's syndrome
 Scleroderma
 Frostbite
 Obliterative vascular disease
 Vasospasm
 Trauma
 Emboli
CONTINUED…

40.  Coagulopathy
 Recent myocardial infarction
 Pathological bradycardia
 Glaucoma
 Allergy to medications
CONTRAINDICATIONS

41. The patient is placed in the supine position
with the neck slightly extended, the head
rotated slightly to the side opposite the block,
and the jaw open.
The point of needle puncture is located
between the trachea and the carotid sheath
at the level of the cricoid cartilage and
Chassaignac's tubercle
Procedure

42. Technique

43.  Cutaneous anaesthesia is obtained with a
skin wheal of local anaesthetic.
 The sternocleidomastoid and carotid artery
are retracted laterally as the index and middle
fingers palpate Chassaignac's tubercle
 The needle is directed onto the tubercle, and
then redirected medially and inferiorly toward
the body of C6.
Technique

44.  After the body is contacted, the needle is
withdrawn 1-2 mm
 This brings the needle out of the belly of the
longus colli muscle, which sits posterior to the
ganglion and runs along the anterolateral
surface of the cervical vertebral bodies
 . The needle is then held immobile.
Technique

45. Technique
 10 ml control syringe charged with local
anaesthetic is attached to the needle and aspiration
is performed to rule out intravascular placement.
 A 0.5 ml test dose is performed to rule out
intravascular injection into the vertebral artery,since
seizures can occur immediately, even with very
small volumes of local anaesthetic
. This test dose is followed by a 3 ml epinephrine-
containing test dose to rule out intravenous
placement.
Now the remaining drug is also injected.

46.  Horner’s syndrome
 The onset of Horner's syndrome indicates a
successful block.
Horner's syndrome is characterised by an
interruption of the oculosympathetic nerve
pathway somewhere between its origin in the
hypothalamus and the eye
Successful block

47. Signs
The classic clinical
findings associated with
Horner's syndrome are
• ptosis
• pupillary miosis
• facial anhidrosis

48. Other findings may include
 apparent enophthalmos
 increased amplitude of accommodation
 heterochromia of the irides (if it occurs
before the age of 2 years)
 paradoxical contralateral eyelid retraction
 transient decrease in intraocular pressure
and changes in tear viscosity
Horner ‘s syndrome

49.  Misplaced needle
Haematoma from vascular trauma
Carotid trauma
Internal jugular vein trauma
Neural injury
Vagus injury
Brachial plexus roots injury
Pulmonary injury
Pneumothorax
Haemothorax
Chylothorax (thoracic duct injury)
Oesophageal perforation
Complications

50. Spread of local anaesthetic
 Intravascular injection:
Carotid artery
Vertebral artery
Internal jugular vein
 Neuraxial/brachial plexus spread:
Epidural block
Intrathecal
Brachial plexus anaesthesia or injury (intraneural injection)
 Local spread:
Horseness (recurrent laryngeal nerve)
Elevated hemidiaphragm (phrenic nerve)
Compliccations

51.  Infection
Soft tissue (abscess)
Neuraxial (meningitis)
Osteitis
Complications

52.  Stellate ganglion block is done to:
 Diagnose the cause of pain in the face and
head, arms and chest
 Manage pain in the head, neck, chest or arm
caused by nerve injuries, the effects of an attack
of shingles (herpes zoster) or angina that
doesn't go away
 Reduce sweating in the face, head, arms and
hands
 Treat reflex sympathetic dystrophy, sympathetic
maintained pain or complex regional pain
syndrome
Summary

53. Textbook Of Human Physiology
Guyton And Hall
Clinical anesthesiology
4th
edition
G. Edward Morgan
References
Clinical anesthesia
6th
edition
paul G. Brasch
Net references from wikipedia.com and frca.co.uk