Case 8 Flashcards

1
Q

What is the difference between epidural and spinal block ?

A

Epidural allows regional pain relief but with ability to mobilise (push) during vaginal delivery. Spinal block to subarachnoid space is more rapid used in Caesarean when mobilisation isn’t required.

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2
Q

What is the common rule for normal symphysis fundal height ?

A

The embryological week age -2 in cm.

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3
Q

What is the difference between the basal and chorionic plate ?

A

Basal = mum’s tissue , chorionic = fetal tissue. Pool of blood in between the two which is full of O2/nutrients/waste.

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4
Q

What are the diaphragmatic openings ?

A

I 8 10 Eggs At 12.
IVC = T8
Eosophagus = T10
Aorta = T12

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5
Q

The umbilical vein brings blood to the foetus. It divides at the liver to form what ?

A

IVC and portal vein.

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6
Q

What is the ‘shortcut’ pathway from the umbilical vein to the IVC ?

A

Ductus venosus

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7
Q

The umbilical arteries take blood to be pooled in the placenta for exchange. What structures feed into them ?

A

The two branches of the internal iliac arteries.

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8
Q

What are the two walls of the foramen ovale and which side are they on ?

A
Septum primum (LA side) 
Septum secundum (RA side)
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9
Q

What structures does the ductus arteriosus connect ?

A

Allows blood flow from pulmonary artery to aorta and then into circulation.

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10
Q

What substance causing contraction of the umbilical arteries and veins in response to decrease temperature immediately after birth ?

A

Wharton’s jelly. squeezes down on the vessels.

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11
Q

What causes the decreased resistance immediately after birth that allows blood into the lungs ?

A

Alveoli fluid is pushed into the capillaries by air. This causes arterioles to dilate. RA/RV pressure decrease.

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12
Q

What happens in response to increased blood flow into the left atrium?

A

The pressure increases in LA so it’s now higher than RA (which is dealing with O2 poor blood). Therefore the foramen ovale closes to stop contamination.

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13
Q

What does the foramen ovale become when closed ?

A

Fossa ovalis, more of a remnant of the fibrous sheet that covered the foramen ovale during development.

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14
Q

Post natal, what does the increase in pressure in the aorta cause ?

A

Pressure in aorta is now > pulmonary artery. This causes contraction of SM of ductus arteriosus from ^ O2.

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15
Q

Placental removal causes a decrease in what substance? This has the knock on effect of…

A

Increased prostaglandins

Ductus arteriosus responds by constricting to form the ligamentum arteriosum.

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16
Q

Blood flow through the umbilical artery stops causing what ?

A

pressure to increase therefore closes its branch with the internal iliac.

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17
Q

What are the two stages of labour in terms of pain ?

A

First, onset to full cervical dilation

Second, full cervical dilation to delivery.

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18
Q

What does the first stage of labour cause ? what substance has increased release ?

A

Repetitive uterine contractions and distension of lower uterine segment. Tissue stretches causing Prostaglandin release.

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19
Q

What is the required level of cervical dilation ?

A

10 cm.

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20
Q

What dermatome controls contraction and using what fibres ? What other structures might be affected ?

A

T10 - L1 in slow unmyelinated C fibres.

Adjacent pelvic structures (L2-S1) might be affected.

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21
Q

What pain sensation do the C fibres give?

A

Visceral crampy poorly localised pain, can be referred. Travel in paracervical ganglion up the lumbar sympathetic chain.

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22
Q

Which pain fibres are triggered in the second stage of labour ? What pain response do they produce ?

A

A delta fast fibres. Sharp and localised pain.

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23
Q

Why doesn’t blocking the pudendal nerve numb the region to pain ?

A

Pudendal nerve supplies the perineum and lumbo sacral plexus. But the perforating branch or post cut thigh, ilioinguinal and gentofemoral also give innervation therefore pain still felt.

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24
Q

What are the two major problems with maternal hyperventilation ?

A

decreased CO2.
1st, left shift of O2 Hb dissociation curve increasing maternal affinity Hb for O2. This then decreases O2 delivery to fetus.
2nd, causes maternal alkalosis which constricts uterine artery and decreases blood flow.

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25
Q

What are the three major types of analgesic options ?

A

non pharmacological (duala, birth partner etc) , Neuraxial (spinal cord) , nerve blocks (peripheral nerves).

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26
Q

What is the effect of C fibres in the spinal cord in inducing nociception ?

A

C fibres stimulate secondary afferents which suppress inhibitory interneurons causing pain gate to open. Therefore C fibres are only pain fibre so strong pain stimulus transmitted -> nociception.

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27
Q

What pain fibres modulate pain in the dorsal horn ? What sensations are they responsible for ?

A

A delta fibres. They synapse inhibitory interneurones and stimulate them decreasing transmission of pain to 2ndry afferents which closes the pain gate.
Pressure and touch.

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28
Q

Why are NSAIDs avoided for pain relief when pregnant/labour ?

A

Causes permanent closure of ductus arteriosus. This affects renal and pulmonary vessels.

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29
Q

What is Pethidine and what is it’s route of administration ?

A

Commenest analgesic. IM injection. sedative that increases fatal blood plasma conc 2-5 hrs post injection.

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30
Q

What is the active metabolite of pethidine ?

A

Norpethidine, sedative.

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31
Q

What is Remifentanil ?

A

highly potent, rapid onset sedative. Acts 90 seconds after administration. Metabolised by tissue esterases.

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32
Q

What is the pathway of an epidural injection ? (6)

A

Skin, subcut tissue, supraspinous and intraspinous ligaments, ligamentum flavium, epidural space

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33
Q

What is the ligamentum flavium ?

A

Yellow layer full of elastic tissue

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34
Q

What are the general qualities of an epidural ? (3)

A

Catheter gives prolonged effect that can be monitored/changed/
Minimal fetal transfer of drugs
No sedation, still mobile.

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35
Q

What is an epidurogram ?

A

Contrast outlining epidural space. Use local anaesthetic and opiate.

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36
Q

What is the route of a spinal injection ? (7)

A

Skin, subcut tissue, supraspinous and intraspinous ligaments, ligamentum flavium, epidural space, dura

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37
Q

What is the conus ?

A

The conical lower extremity of the spinal cord

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38
Q

What level do spinal injections have to be done at and why ?

A

Below the conus (L1-L2) because it avoids the spinal cord. Could/will cause paralysis.

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39
Q

What are the major qualities of the spinal injection ? (3)

A

Minimal fetal transfer of drugs. No sedation. Have to reinfect whereas epidural you can ‘top up’ with catheter.

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40
Q

What are the common complications of neuraxial ? (2)

A

dural puncture -> headache, CSF leak decrease pressure.

Nerve damage; direct = conus nerve root, indirect = haemotoma, abscess.

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41
Q

Why can neuroaxial blocks increase the chance of instrumental delivery ?

A

They can temporarily paralyse delivery apparatus. Decrease urge to push due to decreased sensation. Prolongs 2nd labour stage.

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42
Q

What are the 3 major parts of the placenta?

A

The amnion (water bag) , the chorion (vast majority of weight, composed of villi) and the umbilical cord

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43
Q

What are cells in the placenta that have differentiated from maternal endometrium called ? Why do they change ?

A

Decidual cells.

Levels of progesterone increase.

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44
Q

What is a key component of early breast milk that helps boost an infants immune system?

A

Immunoglobulins

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45
Q

What are the action of myoepithelial cells ?

A

Surround the mammary glands, contract to squeeze out milk toward the nipple.

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46
Q

Why do the mammary glands expand ?

A

stimulation from Oestrogen and progesterone during pregnancy and puberty.

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47
Q

What area is the areola? what is it’s function?

A

Dark circular area that surrounds the nipple. Contains areolar glands which secrete oily lipid fluid to moisturise and prevent cracking/tearing during feeding.
Its colour and smell also attract the infant.

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48
Q

What is the pathway of milk from the mammary glands ?

A

glands , lactiferous ducts, nipple pores, nipple.

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49
Q

What pathway stimulates oxytocin release during lactation ? (6)

A

Infant starts to suckle on a teet.

Mechanoreceptors -> spinal cord -> hypothalamus -> oxytocin neurones in PPG -> Oxytocin ^

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50
Q

What is the negative pathway during lactation ?

A

Infant suckles on teet. -ve signals to prolactin neurones in APG that release prolactin inhibitory neurone therefore prolactin increases. Mammary glands produce more milk.

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51
Q

What are the inactive small areas called in breast histology? often shown as blue

A

Lobules

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52
Q

What is the significance of having more stroma than lobules ?

A

Women is not producing milk. Stroma are areas of CT (pink on histology)

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53
Q

What type of epithelium lines the small ducts within the lobules ?

A

Cubodial epithelium.

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54
Q

What adaptions do acini have in a milk producing breast ?

A

Much larger so they have a higher milk storing capacity.
Very loose CT, supported by oestrogen surrounding the lobules.
Between lobules skin has fat and CT.

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55
Q

What does necrosis within proliferated ducts in breast indicate ?

A

Malignancy, could be linked to chronic haemorrhage.

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56
Q

What is DCIS ? what’s the difference if ducts show infiltrating nests into surrounding tissue?

A

Intraductal carcinoma in situ.

Then it’s not DCIS (intra), actually more dangerous.

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57
Q

How would you identify the fundus of the uterus on palpation?

A

Start at the top and curve fingers into the belly downwards. Feels like a hard ball under the skin.

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58
Q

How would you palate the foetal vertebral column ?

A

Move hand over ‘the bump’ until you feel the ridges

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59
Q

From which two points would you measure the symphysis fundal height from ?

A

Top of the pubic bone to the top of the uterus.

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60
Q

What are the stages to the mechanism of labour ? Do Frogs In Cardiff Ever Ride A Pink Limousine

A

Descent , Flexion, internal rotation, crowning, Extension, Restitution, Internal rotation of the shoulders, Ant shoulder, Post shoulder, Lateral flexion.

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61
Q

Label the anatomy practical diagram on desktop

A
  1. Umbilical Vein
  2. Umbilical artery
  3. Amnion
  4. Pool of blood
  5. Chorionic plate
  6. Uterine wall
  7. Basal plate
  8. Trophoblasts
  9. Intervillus space
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62
Q

What is a cotyledon and what would be your concern if it was missing from delivered placenta ?

A

One of the ‘cobbles’ on the fatal side of placenta. If missing then still attached to mother so will bleed. Uterus can’t contract BVs can’t go back to former state, mum bleeds out.

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63
Q

What is the difference between wall thickness in arteries and veins ?

A

Arteries = thick , Veins = thin

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64
Q

The umbilical vein is obliterated to form…. it divides what structures ?

A

Round ligament/ligamentum teres. Divides the left part of liver and connects it to the abdominal wall.

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65
Q

Picture of the umbilical cord, it forms a face. What are the ‘two eyes’ , ‘the mouth’ , ‘the skin’ and the ‘spots’ ?

A

Two eyes = the two umbilical arteries.
The mouth = the one umbilical vein
The skin = Wharton’s jelly
Spots = embryonic remnant (allantois)

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66
Q

What do the umbilical arteries become ?

A

Medial umbilical ligament and a branch of the sup cervical artery

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67
Q

How does a true knot occur and what can it cause ?

A

Placenta growth ^ or its too long, causes increased movement allows foetus to slip through creating knot.
Intrauterine fatal death because O2 supply cut off.

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68
Q

How are false knots created, why are they often missed ?

A

Varices or dilations of umbilical veins

Not usually visible antenatally.

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69
Q

What is the condition called where the fossa ovalis fails to form postnatally?

A

Patent foramen ovale. Usually occurs when the septum primum and secundum don’t divide the atria completely.

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70
Q

What are the 3 major causes of the ductus arteriosus becoming the ligamentum arteriosum apart from pressure ?

A

Increased bradykinins in the lungs
increase O2 sat of blood
Decrease in circulating prostaglandins and their receptors

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71
Q

What are the function of the Cooper’s ligaments ? What happens during Carcinoma?

A

CT that attach lobules of gland to the overlying skin. If Carcinoma occurs, may result in puckering of nipple or dimpling of the skin.

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72
Q

List some major risk factors for breast cancer… (5)

A

Obesity, high alcohol intake, ^ intake of COCP, HRT (hormone replacement therapy), family history

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73
Q

What adaptions do the secretory cells have of a lactating breast ? (what type of epithelium, components of cell)

A

Depending on the amount of material in the lumen, they can have tall columnar or cuboidal shaped epithelium
Many microvilli on luminal surface
Abundant endoplasmic reticulum and large mitochondria.

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74
Q

What type of gland is the mammary gland ?

A

Compound tubular. Heavily branched with duct portions throughout. Contains secretory and duct cells.

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75
Q

What are the possible causes of px presenting with lactation who is not, and has not recently been pregnant?

A

Shows hormone imbalance. Possibly from pituitary gland, tumours, thyroid gland etc.

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76
Q

What are the methods of preventing lactation following birth ?

A
Not allow the baby to suckle 
Use Cabergoline (dopamine agonist) this can also be used to treat conditions with high levels of prolactin.
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77
Q

Px is diagnosed with fibrocystic change, what would you expect to see; microscopic description, histology

A

Can include mystically dilated normal structures and deposition of fibrous tissue.
More denser CT, may not be abnormal

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78
Q

Why might fibrocystic change be difficult to pick up/diagnose?

A

Similar to young adult breast tissue in appearance (dense). Appears as bright white.

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79
Q

Which nodes do the lateral and medial sides of the breast tissue drain to ?

A
Lateral = axillary nodes 
Medial = Parasternal (they have ^ mortality)
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80
Q

What are the pelvic floor muscles ?

A

Levator ani and bulbospongeous.

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81
Q

What might be the effects of a tear on the mother in the weeks after birth ?

A

Unable to have sex, painful until healed (3 weeks). May also be incontinent.

82
Q

What does the pudendal nerve travel along and is often used as a landmark for ?

A

Ischial spine.

83
Q

What is the ideal length of time for breastfeeding a newborn ?

A

2 years

84
Q

What is the most common region of breast pathologies and why ?

A

Superior lateral, lesions more common because it’s larger than the others. No clinical significance apart form this.

85
Q

What is the arterial supply of the breast ?

A

perforating branches of the internal thoracic.

Mammary branches of the lateral thoracic and some from the intercostal arteries.

86
Q

The veins follow similar pattern to the arteries of the breast. Where do the veins drain into ?

A

Drain into the axillary and internal thoracic veins.

87
Q

Where does the lymphatics of the breast drain into ?

A
Axillary nodes (75%) 
Supraclavicular and infraclavicular nodes
88
Q

What structures may be used during stage 4 breast cancer to initiate metastasis ?

A

Lymphatic nodes of the mammary glands

89
Q

What is the innervation of the breast ?

A

ant and lateral cutaneous branches of the 4th-6th intercostal nerves

90
Q

What function do the nerves have ? what effect would their malfunction have on milk production ?

A

Both sensory and autonomic (SM and BV tone) nerve fibres

No effect, they don’t control milk secretion.

91
Q

What are the borders of the non lactating breast in terms of location relative to the ribs

A

2nd to 6th in the midclavicular line.

Lies in subcutaneous tissue overlying the fascia covering the pec major

92
Q

Why is it easier to pick up tumour shadows on mammograms in elderly females ?

A

with age more glandular elements are lost and become less dense (darker). therefore its’ easier to spot the lesion (white).

93
Q

What are the effects of oestrogen and progesterone on development of lactation system/breats during puberty ?

A

O - stimulates ductal elongation and bifurcation

P - stimulates formation of spherical masses of epithelial cells at the end of each duct (immature alveoli).

94
Q

What is the common increase in breast size during puberty a consequence of ?

A

Increase adipose tissue deposition

95
Q

What divides the lobules of a breast and how many lobules are there roughly per breast ?

A

Fibrous septa

15-25

96
Q

What do the lobules drain into ?

A

10 main lactiferous ducts toward the nipple.

97
Q

What is a TDLU ?

A

Terminal duct lobule unit

End of duct within alveoli.

98
Q

What type of epithelium are the acini cells made of ?

A

Columnar epithelium. Produce milk

99
Q

What type of SM does the nipple have ?

A

Longitudinal and horizontal SM fibres.

100
Q

What is the action of prolactin and human placental lactogen (HPL) during pregnancy ?

A

Promote uptake of protein

Lipolysis

101
Q

What happens to the Sebaceous glands during pregnancy ? how many of them are there ?

A

5-15 ,

Become hypertrophied -> Montgomery’s tubercles.

102
Q

What is the function of Montgomery’s glands ?

A

Keeps the nipple and areola moist and healthy (lipoid fluid)

103
Q

What functions does oestrogen have relative to lactation ?

A

Acts at hypothalamic level to increase prolactin secretion

Suppresses dopamine secretion from hypothalamus.

104
Q

What is the function of Progesterone in lactation ?

A

High levels can inhibit milk secretion. Inhibits alveoli receptors. P interferes with prolactin action at alveolar cells.

105
Q

At birth what are the hormone changes that initiate lactogenesis 2 ?

A

Sudden drop in O, P and HPL. Increase in prolactin.

Increase lactose, IgA, lactoferrin and oligosaccharide.

106
Q

How long does the baby have to latch on until lactation stops due to no milk removal ?

A

3 days.

107
Q

Suckling causes a hormone change and a switch in control of pathway. What are these changes ?

A

Increased release of prolactin and oxytocin

Switch from endocrine to autocrine control (lactogenesis 3)

108
Q

How do the sensory receptors in the nipple coordinate a release of Oxytocin ?

A

Nerve impulses pass via spinal cord and brainstem to the hypothalamus. Hypothalamus then causes PPG to release more Oxytocin (myoepithelium contraction). It also secretes prolactin to increase milk secretion.

109
Q

What is galactopoiesis ?

A

Maintenance of lactation. Continuous suckling is essential for prolactin release from the APG.

110
Q

How does the alveoli shape act to regulate prolactin secretion ?

A

Walls of alveoli become distended, altering prolactin receptor so that binding can no longer occur. Can’t internalise prolactin so synthesis decreases in rate.

111
Q

How does the fat content change with breast volume ?

A

Emptier breast = higher fat content. Fat globules absorb to alveolar membranes only displaced when gland is fully emptied.

112
Q

What is the action of cortisol on prolactin ?

A

Interferes with the binding of prolactin, milk ejection reflex is inhibited.

113
Q

How does breastfeeding act as a contraceptive ?

A

‘lactional amonorrhea’, disrupts pulsatile GnRh release from hypothalamus and hence LH from the pituitary.

114
Q

What is the composition of milk in the first week ?

A

‘Colostrum’, rich in ADEK, proteins/minerals. Contains immunoglobulins to help build the immune system. 50kcal/ml.

115
Q

How does the milk composition start to change after 5 weeks ?

A

Increased calorific content due to increased fat, sugars, amino acids. 75 kcal/10ml.

116
Q

What is the synthesis of lactose dependant on ?

A

a-lactoalbumin. Lactose promotes growth of intestinal flora, helps synthesise over 50 different oligodendrocytes.

117
Q

What two immunoglobulins are low in the transient period so need to be received from mother/formula ?

A

IgA and IgG

118
Q

What is the function of IgA and where is it found ?

A

Protects against pathogens.

Mucous salvia tears breast milk

119
Q

What is the function of IgD ?

A

Activates basophils and mast cells. Part of the B cell receptor

120
Q

What is the function of IgE , what response is it part of ?

A

Protects from parasitic worms

Responsible for allergic reactions.

121
Q

Where is IgG secreted from? what is its special function ?

A

Plasma cells

Can cross the placenta into the foetus

122
Q

What is the function of IgM, what structures can it attach to ?

A

Early immunity stages before there’s sufficient IgG.

Attaches to B cell surface and/or can be secreted into the blood

123
Q

What is a double blinded trial ?

A

volunteer and administrator don’t know the treatment they’re giving/receiving

124
Q

What is a crossed over trial ?

A

Every volunteer gets every treatment. Not always possible if treatment is curative in volunteer.

125
Q

What is a randomised trial ?

A

Avoids gathering biased data from particular demographics. Random patient and drug

126
Q

What is a placebo controlled trial ?

A

Stimulated medical treatment that contains no pharmacologically active ingredient. May be considered as a reference control for actual drug treatments.

127
Q

What is the effect of a LA on Na channels ?

A

Block voltage gated Na channels in neuronal axons forcing them into inactive state.

128
Q

What unit is targeted by a LA

A

alpha subunit on the systolic side.

129
Q

What is the effect of Bupivacaine epidural.?

A

Labour inducing, provides pain relief without affecting motility.

130
Q

What does the pKa of a particular drug indicate ?

A

The pH at which 50% of the drug is ionised.

131
Q

What is the issue with use of LAs when the extracellular pH is above 7 ?

A

LAs are weak bases. If pH is above 7 they won’t ionise and will be able to cross cell membrane. They then ionise intracellularly due to the pH of cortisol.

132
Q

Why might adrenaline be given along side an LA

A

Binds to adrenergic receptors in periphery -> vasoconstriction. Therefore drug is cleaved slower from the site due to reduced blood flow so LA lasts longer.

133
Q

Why do you never give adrenaline injections into the spinal cord ?

A

Vasoconstriction of the surrounding muscles which could cause permanent paralysis.

134
Q

Why do you never inject adrenaline into the pudendal nerve ? Where else might this same principle be applied to ?

A

Vagina has no collateral blood supply so will go gangrenous under adrenaline. Same applies for peripheral digits.

135
Q

What fibres does an epidural target ?

A

A delta and C fibres (pain).

136
Q

What structures arise from the mesoderm layer ?

A

Heart, blood vessels and blood cells

137
Q

What is vasculogenesis ?

A

Development of new BVs occurs from endothelial cells developing in situ

138
Q

What is angiogenesis ?

A

Formation of new BVs in embryo sprouting from new capillaries of pre existing vessels. Many diseases originate from angiogenesis

139
Q

In BV formation, mesodermal aggregates ‘blood islands’ form composed of what ? where are they formed ?

A

Haemioangioblasts

Extraembryonic tissues

140
Q

What is the decider parietalis and what is its function ?

A

mucous membrane in pregnant uterus not beneath the placenta. Key involvement in providing nourishment in early embryo. Limits trophoblast invasiveness

141
Q

What is the primary stage of the villus ?

A

Core of cytotrophoblasts covered by synctiotrophoblasts. Finger projections form invasive cells.

142
Q

What is the secondary stage of the villus?

A

mesoderm core, vasculogenesis blood island formation. Forms circulatory system in placenta.

143
Q

What is the tertiary stage of the villus

A

Villus capillary formed.

144
Q

How does the thickness of the fatal maternal barrier change between 10 weeks and full term ?

A

10 weeks = 25 um

Full term = 2.5 um

145
Q

What are the first signs of heart formation ?

A

Clusters of endothelial cells (angioblasts) form with myoblasts (cardiac) from the mesoderm in the heart forming regions (starts 17-18)

146
Q

What happens when the clusters of cardiac cells coalesce ?

A

They form the heart tube. Other clusters form dorsal arose through vasculogenesis

147
Q

What type of folding of the heart tube and pericardial cavity pushes toward the thoracic region after 20-22 days ?

A

Cephalocaudal.

148
Q

What are the 5 dilatations of the heart tube.?

A

Truncus arteriosus , bulbus cordis, primitive ventricle, primitive atrium, sinus venosus

149
Q

You’re viewing a fatal heart and see the intraventricular foramen and septum are visible. What day of development is this heart in ?

A

30 days , primitive atria and ventricles also become visible

150
Q

Between what time period does the heart divide into the typical 4 chambered structure ?

A

Weeks 4-7

151
Q

After the 5th week the SAN begins to form. How does this formation occur ?

A

Cardiac myocytes of sinus venosus begin to depolarise spontaneously. Looping occurs and SV incorporated into the RA becoming Sino atrial node.

152
Q

What is the name of the holes between the right and left atria in the fatal heart ?

A

Ostium primum and secondum, relative to the septa they arise from

153
Q

what ? ridges form in the walls of the trunks arteriosus and conus cordis in week 5 of development over a weeks time they fuse to form what ? This divides outflow tract into what and what ?

A

Conotruncal ridges
Spiralling septum
Pulmonary artery and aorta

154
Q

After what time period is the heart structure formed for the rest of uterine life ?

A

Week 7

155
Q

Px has a blood test. Their RBCs react with patient anti-B and their plasma cells react with A cells. What can we deduce about their blood type ?

A

B
Patient’s RBCs react with anti B therefore B is present.
Plasma contains anti A so this reacts with the A cells and confirms the above.

156
Q

When carrying out a blood test for Rhesus antigens, what else do you have to do at the same time ?

A

Have two control plates setup up with Anti D plus one of D+ and D- controls.

157
Q

How would you test for rhesus antigens and what would be the result ?

A

Setup a plate with anti-D and px RBCs. If there is a reaction then px is +ve otherwise they’re -ve.

158
Q

If px has blood type B- , what blood groups can they receive from ?

A

B-, O-

159
Q

Why would you give a mother anti D after 28 and 34 weeks ?

A

If foetus is D+ , the mum will produce antibodies that could harm future pregnancies.

160
Q

What is significant about the Rhesus D antibodies that means they could harm the foetus ?

A

They’re IgG so can cross the placenta

161
Q

If the mother was D- and foetus D+ what harm could potentially be caused ?

A

HDN -> Haemolysis -> still birth/anaemia.

162
Q

What is the potential harm if the mother is D+ and the foetus is D- ?

A

This is fine because no antibodies will be produced

163
Q

What is the Kleihauer method ?

A

Determines wether there has been any fatal haemorrhage into maternal circulation

164
Q

How would the different haemoglobin be represented by acid elution ?

A

Fetal haem (HbF) are more resistant to acid elution so appear as isolated dark red stains relative to the pale pink maternal ‘Ghost cells’.

165
Q

Where do the Anti A/B antibodies originate from ?

A

Surgars shared with receptors on surface of gut bacteria

166
Q

What antibodies would be present in the blood plasma if the px was blood type AB ?

A

None

167
Q

Px has blood group O, what antigens would be present on the surface of cells?
What antibodies would be present in the blood plasma ?

A

No antigens on cell surface

Both anti A and B would be present in the plasma

168
Q

Why is RBC resuspended in optimal additive solution ?

A

Enhances the viability and stores better. The solution contains glucose which stores better.

169
Q

What temperature is the blood stored at and why ?

A

4 degrees C, prevents/limits bacteria growth.

170
Q

Why is the blood first irradiated ?

A

Prevents passenger lymphocytes from engrafting into the hosts

171
Q

What is the process of Leucodepletion and why is it used today ?

A

Removal of WBCs (standard for RBCs and platelets)
The risk of CMV greatly decreases.
Cytomegalovirus

172
Q

What are two typical clinical settings for blood transfusions ?

A

Acute/chronic anaemia, preoperative blood loss

173
Q

What are the alternatives to blood transfusions ?

A

Iron, folate, B12

174
Q

What temperature is Fresh frozen plasma stored at and how long does it last ?

A

Stored at -30 degrees and last 24 months

175
Q

Why might platelet donation be used ?

A

Treatment of haemorrhage is patient has thrombocytopenia or platelet function defects.

176
Q

What is TACO and what can it result in?

A

Transfusion associated circulatory overload. Too much given to a particular patient. Risk increases for chronic anaemia.

177
Q

What affect does poor nutrition in development have on growth relative to thriftiness ?

A

poor food = poor growth

62% variation In birthweight is environment.

178
Q

What epigenetic changes can occur as a result of thriftiness ? (6)

A

Birth weight, metabolism, growth, glucose tolerance, BP, adiposity.

179
Q

What effect can an iron def in the mum have on the placenta ?

A

Lack of vasculature of the placenta

180
Q

What happens if blood flow is comprimised in utero ?

A

Blood shunts to the heart. Vasoconstriction of the aorta so blood goes to the brain and not the peripheral organs. If prolonged much smaller growth and decreased blood measurements.

181
Q

What happens to cortisol levels if baby is born smaller than expected ?

A

Increased cortisol levels to more stress for the baby

182
Q

What effect does IUGR have on the pancreas ?

A

Restricted blood flow so reduced growth. Therefore less B cells will be produced. Leads to small size and B cell dysfunction.

183
Q

Why are obese mothers more likely to produce obese babies ?

A

Too much nutrition available to foetus so adapts to overfeeding (thrifty). Glucose crossing the placenta stimulates insulin production in the foetus.

184
Q

What are the major components of breast feeding ?

A

Decreases chance of type 1+2 diabetes, protects against hypertension, less likely to be obese, less fat (better proteins and hormones) , slower growth but controlled ‘yoyo’ around percentiles.

185
Q

What is the normal haemoglobin range for women ?

A

115-165 g/l

186
Q

What are the extremes of haemoglobin levels called and what do they look like under a microscope ?

A

Anaemia (low) rare dots throughout cell

Polycythaemia (high) lots of dots and squiggles going on

187
Q

How does plasma volume vary through pregnancy and what is it roughly ?

A

Increases throughout, plateaus last 8 weeks

2600 ml.

188
Q

How much does RBC volume increase by during pregnancy and what proportion is that relative to total volume?

A

240ML , 17%

189
Q

What is the physiologically low point of haemoglobin saturation ?

A

Dips between 20-24 weeks, if still low after 34 then anaemic.

190
Q

What happens to red cell mass immediately post partum ?

A

Dips largely due to blood loss, should increase back to normal after 3 weeks.

191
Q

What is excess iron converted to in the liver and bone marrow ?

A

Liver = ferritin

Bone marrow = Hemosiderin

192
Q

How does the iron requirement vary between; adult male, menstruating female, pregnant female ?

A
Male = 1 mg/day
Menstruating = 2 
Pregnant = 4-7
193
Q

What levels of; haemoglobin, serum ferritin and MCV indicate iron def in pregnancy ?

A

Haemoglobin <105 (below 115 monitor)
Serum ferritin <15 mcg/l
MCV < 80 fl with associated symptoms.

194
Q

What level would you expect the Hb to ^ by once starting treatment of iron deficiency ?

A

10 g/L/week

195
Q

What are the reasons for Hb not ^ once started treatment (3)

A

Not taking the tablets
Poor absorption
Not deficient (other cause)
RBCs only produce at constant rate so having excess iron makes no difference

196
Q

Why would you take oral iron tablets as opposed to IV ?

A

IV shows no real benefit and increased risk of anaphylaxis

197
Q

How does the normal requirement of B9 differ to that of a pregnant lady ?

A

100 –> 300/400 mg/day.

198
Q

What is the normal platelet count ? What are high and low levels of platelets called?

A

150-450 x10^9
Thrombocytopenia = low
Thrombocytosis = high

199
Q

1/3 of bone marrow is made of fat cells. What is bone marrow failure a likely result of ?

A

Decreased production from aplastic anaemia. Due to malignant infiltration of the bone marrow. No space for making WBC/RBC/platelets.

200
Q

What is a decrease in WBC number called ?

A

Leucopenia

201
Q

What is the blood picture in increased consumption ?

A

Normal WBC/RBC

platelets decrease

202
Q

Which side does 90% of DVT occur on and why ?

A

Left side

Right common iliac crosses IVC before joining aorta it becomes compressed and clots. More likely to be proximal