Physiology in pregnancy

Question 1

what general changes are seen in pregnancy

Answer 1

mechanical systems
metabolism
fatigue (particularly early)
heartburn/reflux
oedema
breast changes
thyroid changes
general state of immunosuppresion
weight gain

Question 2

how does the appearance of the breasts change in pregnancy

Answer 2

increased size
increased pigmentation of the areola/nipple
secondary areola appears
montgomery tubercules appear on the areola

Question 3

what happens to the vascularity of the breast

Answer 3

increased vascularity - breasts become warm and tender

Question 4

what is expressed from the breasts and when

Answer 4

colostrum like fluid from the end of the third month

Question 5

when do changes to the CVS start occurring

Answer 5

significant changes in the early first trimester

Question 6

what happens to circulating blood volume

Answer 6

increased circulating blood volume

- 50-70% higher than non-pregnant

Question 7

what happens to vascular resistance and when

Answer 7

systemic vascular resistance falls - maximal fall at 20-32 weeks

Question 8

in relation to the CVS what occurs when a pregnancy women is in the supine position

Answer 8

25% reduction in cardiac output

Question 9

what are some other cardiac changes

Answer 9

increased blood flow
increased CO (40%)
increased stroke volume
increased heart rate
increased O2 consumption

Question 10

what is intrapartum

Answer 10

period of time from the onset of labour to the end of the third stage of labour

Question 11

what are some intrapartum CVS changes

Answer 11

autotransfusion of contractions (blood transferred from uterus to maternal circulation

pain - increasing catecholamines

Cardiac Output increases by 10% in labour and by 80% in 1st post delivery hour

Question 12

when does the CVS return to normal after pregnancy

Answer 12

mostly by 3 months

Question 13

what happens to blood volume postpartum

Answer 13

decreased by 10% 3 days postpartum

Question 14

what happen to BP postpartum

Answer 14

initially falls then increased again days 3-7 (back to pre pregnancy levels by 6 weeks)

Question 15

what happens to systemic vascular resistance postpartum

Answer 15

increased over first 2 weeks to 30% above delivery levels

Question 16

what happens to heart rate postpartum

Answer 16

returns to pre preg level over 2 weeks

Question 17

what happens to cardiac output postpartum

Answer 17

increase up to 80% 1st hour post delivery then continues to fall over the next 24 weeks

Question 18

what happens to O2 demand in pregnancy

Answer 18

increases up to 20%

Question 19

what happens to minute ventilation during pregnancy

Answer 19

increaes 40-50%

Question 20

what other respiratory factors increase during pregnancy

Answer 20

increased resp rate

increased tidal volume

Question 21

what respiratory factors decrease during pregnancy

Answer 21

decreased functional residual capacity

decreased PCO2

Question 22

what respiratory factors remain unchanged during pregnancy

Answer 22

PEFR - peak expiratory flow rate

FEV1 - forced expiratory volume in 1 minute

Question 23

what happens to the urinary collecting system during pregnancy

Answer 23

dramatic dilatation - more pronounced on the right

Question 24

what happens to renal plasma flow during pregnancy

Answer 24

60-80% increase by end of second trimester

Question 25

what other renal system factors increase

Answer 25

increased GFR and creatinine clearance (50%) increased protein excretion increased rate with increasing gestation

Question 26

what renal system factors decrease

Answer 26

decreased urea | decreased creatinine

Question 27

what other renal changes are seen in pregnancy

Answer 27

oedema in 80% of women glycosuria common microscopic haematuria may be present

Question 28

what haematological increases are seen in pregnancy

Answer 28

plasma volume increased (cf to birthweight) 2-3 fold increase in iron requirement 10-20 fold increase in late requirements WCC increases

Question 29

what haematological decreases are seen in pregnancy

Answer 29

decreased hg, script, rcc | decreased platelet count

Question 30

what happens to the coagulable state during pregnancy

Answer 30

becomes hyper coagulable

Question 31

recap - lab values that decrease

Answer 31

``` Hg Platelets (or stay the same) Urea Creatinine Urate (but increases with gestation) total protein albumin AST/A:T/GGT ```

Question 32

recap - lab values that increase

Answer 32

``` WCC ESR 24hr protein Alkaline phosphate (***) D dimer ```

Question 33

recap - lab values that stay the same

Answer 33

bile acids AST/ALT/GGT (sometimes) Platelets (sometimes)