Clinical Anatomy of Anaesthesia for Labour

Question 1

What are the reproductive system’s motor functions?

Answer 1

Uterine cramping e.g. menstruation
Uterine contraction e.g. during labour
Pelvic floor muscle contraction e.g. during sneezing

Question 2

What is the reproductive system’s pain (sensory) function?

Answer 2

Pain from adnexal (ovaries + Fallopian tubes)
Pain from uterus
Pain from vagina
Pain from perineum

Question 3

Above the levator ani muscles is referred to as?

Answer 3

Pelvis

Question 4

Below the levator ani muscle is referred to as?

Answer 4

Perineum

Question 5

What supplies structures of the pelvis?

Answer 5

Body cavity
Sympathetic, parasympathetic and visceral afferent

Question 6

What supplies structures of the perineum?

Answer 6

Body wall
Somatic motor and somatic sensory

Question 7

What structures are below and above levator ani muscle in the reproductive system?

Answer 7

Question 8

What nerve fibres supply uterine cramping e.g. menstruation?

Answer 8

Hormonal (symp/parasymp)

Question 9

What nerve fibres supply uterine contraction e.g. during labour?

Answer 9

Hormonal (symp / parasympathetic)

Question 10

What nerve fibres supply pelvic floor muscle contraction e.g. during sneezing?

Answer 10

Somatic motor

Question 11

What nerve fibres supply pain from adnexae?

Answer 11

Visceral afferents

Question 12

What nerve fibres supply pain from uterus?

Answer 12

Visceral afferents

Question 13

What nerve fibres supply pain from vagina?

Answer 13

Visceral afferents (pelvic part)
Somatic sensory (perineum)

Question 14

What nerve fibres supply pain from perineum?

Answer 14

Somatic sensory

Question 15

Superior aspect of pelvic organs / touching the peritoneum are supplied by what nerve fibres?

Answer 15

Visceral afferents
Run alongside sympathetic fibres

Question 16

Visceral afferents from the Superior aspect of pelvic organs / touching the peritoneum enter spinal cord between?

Answer 16

T11-L2

Question 17

Pain is perceived as what from Superior aspect of pelvic organs / touching the peritoneum ?

Answer 17

Suprapubic

Question 18

Inferior aspect of pelvic organs / not touching peritoneum are supplied by what nerve fibres?

Answer 18

Visceral afferents
Rung alongside parasympathetic fibres

Question 19

Inferior aspect of pelvic organs / not touching peritoneum enter spinal cord at what levels?

Answer 19

S2, S3 and S4

Question 20

Pain is perceived as what from Inferior aspect of pelvic organs / not touching peritoneum?

Answer 20

In S2, S3 and S4 dermatomes (perineum)

Question 21

Structures crossing from pelvis to perineum above the levator ani (in pelvis) are supplied by what?

Answer 21

Visceral Afferents
Parasympathetic

Question 22

The nerve fibres from Structures crossing from pelvis to perineum above the levator ani (in pelvis) enter spinal cord where?

Answer 22

Levels S2, S3 and S4

Question 23

Structures crossing from pelvis to perineum below levator ani (in perineum) are supplied by what fibres?

Answer 23

Somatic sensory
Pudendal nerve

Question 24

Nerve fibres from Structures crossing from pelvis to perineum below levator ani (in perineum) enter where in spinal cord?

Answer 24

Levels S2, S3 and S4

Question 25

Pain from Structures crossing from pelvis to perineum below levator ani (in perineum) are perceived where?

Answer 25

Localised pain within perineum

Question 26

The sympathetics from pelvis are supplied by what?

Answer 26

Sacral sympathetic trunks T11-L2 Superior hypogastric plexus

Question 27

The parasympathetics to pelvis are from where and what nerves?

Answer 27

Sacral outflow (S2,3,4) Pelvic splanchnic nerves Emerge from spinal roots Mixes with sympathetics in inferior hypogastric plexus

Question 28

What are the 2 important spinal cord levels from where pain from female reproductive system arises?

Answer 28

T11-L2 S2-S4

Question 29

Describe the path of visceral afferents in female pelvic pain

Answer 29

Question 30

Describe the path of the pudendal nerve in female pelvic pain

Answer 30

Question 31

Draw out a diagram explaining the nerve supply from perineum or pelvis

Answer 31

Question 32

What anaesthesia procedures of the pelvis exist?

Answer 32

Question 33

A spinal block via lumbar puncture anaesthetises what?

Answer 33

From waist down - intra and sub peritoneal plus somatic areas

Question 34

A caudal epidural block anaesthetises what?

Answer 34

Sub-peritoneal plus somatic areas innervated by pudendal nerve

Question 35

A pudendal nerve block anaesthetises what?

Answer 35

Areas innervated by pudendal nerve

Question 36

The spinal cord becomes caudal equine at what vertebral level?

Answer 36

L2 vertebra

Question 37

The subarachnoid space ends at level of?

Answer 37

S2

Question 38

Spinal and epidural Anaesthetic is injected into what region?

Answer 38

L3-L4 (L5) region

Question 39

The needle passes through what in an epidural anaesthetic?

Answer 39

Supraspinous ligament Interspinous ligament Ligamentum flavum Epidural space (fat and veins)

Question 40

The needle passes through what in spinal anaesthetic?

Answer 40

Supraspinous ligament Interspinous ligament Ligamentum flavum Epidural space (fat and veins) Dura mater Arachnoid mater Finally reaches subarachnoid space (contains CSF)

Question 41

All spinal nerves and their named nerves contain?

Answer 41

Sympathetic fibres

Question 42

Sympathetic fibres supply all of what vascular structure?

Answer 42

Sympathetic fibres supply all arterioles

Question 43

Blockade of sympathetic tone to all arterioles in lower limb in a spinal anaesthetic can lead to what?

Answer 43

Vasodilation and subsequently hypotension

Question 44

Sympathetic nerves exit spinal cord with what spinal nerves?

Answer 44

T1-L2 spinal nerves

Question 45

Sympathetic nerves travel to what?

Answer 45

Sympathetic chains and pass into all spinal nerves

Question 46

What happens to sympathetic outflow below L2 level?

Answer 46

Sympathetic ganglia receive fibres from L2 level via sympathetic chain and distribute them via connections with lumbar, sacral and coccygeal spinal nerves

Question 47

The pudendal nerve plays a role in?

Answer 47

GI system Renal system Role in motor control of external anal and external urethral sphincters

Question 48

The pudendal nerve is the nerve of?

Answer 48

Perineum

Question 49

The pudendal nerve is a branch of?

Answer 49

sacral plexus S2, S3 and S4

Question 50

Describe the pathway of the pudendal nerve

Answer 50

Exits pelvis via greater sciatic foramen Passes posterior to sacrospinous ligament Re enters pelvis / perineum via lesser sciatic foramen Travels in pudendal canal Branches to supply structures of the perineum

Question 51

The pudendal nerve crosses posterior to?

Answer 51

The lateral aspect of the sacrospinous ligament

Question 52

What bony landmark can be used to identify pudendal nerve?

Answer 52

Ischial spine

Question 53

When can pudendal nerve block be used?

Answer 53

Can be used during labour Forceps delivery Painful vaginal delivery Episiotomy incision Perineal suturing post delivery

Question 54

During labour, what can be stretched?

Answer 54

The branches of pudendal nerve can be stretched

Question 55

Fibres of what muscles can be torn during labour?

Answer 55

Fibres within levator ani (puborectalis) or external anal sphincter muscle could be torn 1st degree 2nd degree 3rd degree 4th degree

Question 56

What is a episiotomy?

Answer 56

deliberate incision that is made, made from posterior forchettte out to sischioanal / ischiorectal fossae - fat filled space - prevents tearing going towards external anal sphincter. Also to avoid perineal body Posterolateral (mediolalateral) incision