Session 8

Question 1

When do most of the Cardiovascular changes occur in pregnancy?

Answer 1

The first trimester

Question 2

What effect does pregnancy have on Blood volume?

Answer 2

It increases it, probably to account for the blood loss that occurs at delivery - around 2L

Question 3

What effect does pregnancy have on Cardiac output, Stroke volume and Heart rate?

Answer 3

All increase

Question 4

What effect does pregnancy have on Blood pressure?

Answer 4

It is never normally increased

Hypotension may occur in the first and second trimester

Question 5

Why does Hypotension occur in the first and second trimester?

Answer 5

Progesterone has an effect on smooth muscle, causing it to relax so there is less resistance

Question 6

What other Cardiovascular changes occur in pregnancy?

Answer 6

The apex beat is displaced
Vasodilation of the endothelium
Aortocaval compression due to the gravid uterus

Question 7

What are the Cardiovascular changes in a Pre-Eclamptic pregnancy?

Answer 7

Vasoconstriction of vessels

Plasma contracted

Question 8

Why does Pre-Eclampsia occur?

Answer 8

Increase in blood pressure due to placenta defect
Proteinura due to failing of the kidneys
Defect in placentation leads to poor uteroplacental circulation and widespread endothelium dysfunction making a greater demand on the mother. Causing an increase in blood pressure and possibly organ damage

Question 9

What is Eclampsia?

Answer 9

A seizure that occurs due to the effects of Pre-Eclampsia on the brain

Question 10

What effect does pregnancy have on the Glomerular Filtration Rate?

Answer 10

It increases - Related to the relaxation effect of Progesterone on smooth muscle

Question 11

What effect does pregnancy have on the renal plasma flow?

Answer 11

It increases it

Question 12

What effect does pregnancy have on the Filtration capacity?

Answer 12

It remains intact unless there are disease processes occuring

Question 13

What effect does pregnancy have on Functional renal reserve?

Answer 13

Decreases as Glomerular Filtration Rate increases

Question 14

What effect does pregnancy have on Urea?

Answer 14

Decreases to around 50% (Around 3.1mmol/L)

Question 15

What effect does pregnancy have on Creatinine?

Answer 15

Decreases to around 25-75 micromol/L

Question 16

What effect does pregnancy have on Creatinine Clearance?

Answer 16

Increases

Question 17

Why are pregnant females more likely to develop UTIs?

Answer 17

Progesterone’s effect on urinary collecting system can cause urinary stasis which can cause infections, possibly ascending up the urethra to cause Pyelonephritis (Causing pre-term labour)
Can also cause Hydroureter

Question 18

What anatomical changes occur to the Respiratory system during pregnancy?

Answer 18

Diaphragm displacement

Anterior to Posterior and Transverse diameters of the thorax increase

Question 19

What physiological changes occur to the Respiratory system during pregnancy?

Answer 19

Increased alveolar ventilation
Increased tidal volume
Unchanged resp rate

Question 20

What effect does pregnancy have on functional residual capacity?

Answer 20

Decreases

Question 21

What effect does pregnancy have on vital capacity and total lung capacity?

Answer 21

Unchanged

Question 22

Why does physiological hyperventilation occur in pregnancy?

Answer 22

There is an increased metabolic production of CO2 due to the foetus.
There is an increased respiratory drive due to progesterone’s effect on the respiratory centre in the brain
Respiratory alkalosis compensated for by increased renal bicarbonate excretion

Question 23

How is glucose transported across the placenta?

Answer 23

Facilitated diffusion

Question 24

How does pregnancy effect glucose metabolism?

Answer 24

There is an increased resistance to insulin

Gluconeogenesis is used with alternative fuels

Question 25

What changes the metabolism of glucose in pregnancy?

Answer 25

Human Placental Lactogen - HPL (& Prolactin, Cortisol, Oestrgen/Progesterone)

Question 26

What is Gestational diabetes?

Answer 26

Carbohydrate intolerance first recognised in pregnancy and not persisting after delivery *Oral glucose test required*

Question 27

What are the risks associated with poorly controlled Gestational diabetes?

Answer 27

``` Macrosomic foetus (Large) Still birth Increased rate of congenital defects ```

Question 28

What effect does pregnancy have on Lipolysis?

Answer 28

Causes it to increase from the second trimester

Question 29

What effect does progesterone have on appetite?

Answer 29

Increases it so fat stores can be laid down ready for pregnancy

Question 30

What effect does pregnancy have on free Fatty Acids?

Answer 30

Increase in the plasma on fasting so there is a substrate for the maternal metabolism, leaving glucose for the foetus

Question 31

Do Fatty Acids cross the placental membrane?

Answer 31

They tend not to, there is also an increased risk of acidosis in the mother

Question 32

How does pregnancy effect the thyroid?

Answer 32

Thyroid binding globulin is increased which causes T3 & T4 to be increased too. Free T4 still remains in the same range hCG decreases TSH production

Question 33

What anatomical changes occur to the GI system in pregnancy?

Answer 33

Alternatives in the place of the viscera eg appendix moves to URQ

Question 34

What physiological changes occur to the GI system in pregnancy?

Answer 34

Smooth muscle relaxation due to progesterone, can cause delayed emptying

Question 35

What is there an increased risk of in pregnancy? (Regarding the GI system)

Answer 35

Pancreatitis - possibly due to the increased lipids | Gall stones/Cholecystitis - due to changes in bile salt concentration

Question 36

What haematological changes occur during pregnancy?

Answer 36

Pro thrombotic state Increased fibrin deposition at the implantation site Increased fibrinogen & clotting factors Decreased fibrinolysis

Question 37

What risk is associated with pregnancy? (Regarding Haematological changes)

Answer 37

Increased risk of thrombi forming due to changes and stasis and venodilation Thromboembolic disease in pregnancy *BUT cannot give warfarin due to its ability to cross the placenta and being tetratogenic*

Question 38

Why is there an increased risk of anaemia during pregnancy?

Answer 38

The plasma volume increases Red cell mass increases, but not by as much Physiological anaemia *Have to be aware that pathological anaemia may occur due to iron or folate deficiency too*

Question 39

What changes occur to the immune system during pregnancy?

Answer 39

The foetus is an allograft, therefore changes have to occur to permit survival There is local non specific suppression of the immune response at the maternal/foetal interface Antibodies are transferred to the foetus (IgG)

Question 40

What causes Haemolytic disease of the newborn?

Answer 40

Anti Rhesus antigens go to the foetus which has Rhesus antibodies on its red blood cells. These are then destroyed leading to anaemia

Question 41

Can a foetus inherit graves disease/Hashimotos disease from the mother?

Answer 41

Yes, as its autoimmune the antigens can cross the placental membrane and cause the same disease in the foetus