Physiology in Pregnancy Flashcards Preview

Yr3 Reproductive > Physiology in Pregnancy > Flashcards

Flashcards in Physiology in Pregnancy Deck (31)
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1
Q

List some General changes to the body during pregnancy?

A
  • Increased lumbar curvature to compensate for the belly
  • Fatigue
  • Reflux due to loosening of GI sphincters
  • Oedema
  • Breast
  • Thyroid (iodine used up so thyroid enlarges to compensate)
  • General Immunosuppression
  • Weight Gain
2
Q

How does the breast change durine pregnancy?

A
  • Bigger and more vascular (warm, tense & tender)
  • Areola/nipple get darker & 2nd* areola appears
  • Montgomery tubercules appear on areola
  • Colostrum like fluid from as early as 3rd trimester
3
Q

How does blood volume change during pregnancy?

A

Up to 50-70% more blood volume while pregnant

4
Q

How does heart activity change during pregnancy?

A

SV & HR rise leading to a much higher CO. Most women have Sinus Tachycardia during pregnancy

SVR also drops significantly

5
Q

Why does CO increase so much during pregnancy?

A

Because O2 consumption goes way up

6
Q

How can changing position affect a pregnant woman’s CO?

A

If they lie supine the foetus presses on the IVC reducing venous return and so reducing CO.

7
Q

Why is it important to understand how a pregnant woman’s CO decreases in supine position?

A

Trying to do CPR & resuscitation on a pregnant woman is impossible if lying supine, you must move the uterus or lie then tilted.

Also never examine a pregnant woman supine, let them sit up or lie on the side

8
Q

How does increased CO affect risk of heart problems?

A

Increased CO means the heart muscle requires more O2. Thus there’s an increased risk of angina or MI

9
Q

How does blood volume & pressure during labour?

A

Every contraction pushes blood from uterus into systemic circulation (Autotransfusion).

This increases blood volume and BP so is dangerous, especially in people with existing BP problems or stenotic lesions

10
Q

How does CO change durine labour?

A

Increases by 10% during labour and up to 80% in the first hr post-delivery. So they’re still at massive risk after delivery.

11
Q

When does the CV system return to normal after pregnancy?

A

Most are back to normal within 3 months

12
Q

How long does BP take to return to normal?

A

It falls and icnreases again in the first 7 days but returns to pre-preg levels by 6wks

13
Q

How long before HR returns to normal?

A

2 wks

14
Q

How long before CO returns to normal?

A

incerases by 80% in first hour post delivery then falls back to normal over 24 weeks

15
Q

How do the lungs change during pregnancy?

A

40-50% increae in ventilation with RR & TIdal volume increasing. (to compensate for increases O2 demand)

But PEFR & FEV1 are unchanged

16
Q

How do O2/CO2 levels change during pregnancy?

A

O2 rises and CO2 drops due to increased ventilation. So looks like compensated respiratory alkalosis on blood gases.

17
Q

How does the renal system change structurally during pregnancy?

A

It dramatically dilates (particularly on the right). Both the ureters and kidneys dilate due to pressure from uterus and progesterone

18
Q

How does function of the kidneys change in pregnancy?

A

Renal plasma flow goes up by 60-80% by end of trimester 2

  • -> Increased GFR & Creatinine clearance
  • -> Urea & Creatinine fall

Protein excretion goes up ergo 24hr urine protein rises and total protein/Albumin drop

Urate rises with gestation

Glycosuria is common

19
Q

What is uric acid level used for in pregnancy?

A

A marker of pre-eclampsia

It also increases with gestation so the level can be predicted based on gestational age

20
Q

How do RBC count change during pregnancy?

A

It actually doesn’t.

but blood volume does so Hg, Hcrit and RCC all appear to drop

21
Q

How does platelet count change?

A

Drops but only by dilution of increased plasma

22
Q

How does WCC change?

A

Increases

23
Q

How does coagubility change?

A

Increases (Hypercoaguable)

24
Q

Describe some increased haematological demands of the body during pregnancy?

A

Iron demand double or triples –> Iron supplements

10-20x increase in folate needs –> Folic Acid supplements

25
Q

Due to hypercoagubility pregnant women are at risk of DVTs & PEs, how can we help at risk women?

A

They can be given daily Dalteparin (LMWH) injections throughout pregnancy and for 6 wks after.

26
Q

What happens to ESR during pregnancy?

A

Rises, so we can’t use it as a marker of inflammation

27
Q

Why do pregnant women get so much oedema?

A

Increased blood volume & pressure coupled with drop in albumin

28
Q

How do liver enzymes change during pregnancy?

A

AST/ALT/GGT can drop

ALKP rises

29
Q

Why does Alkaline phosphatase rise during pregnancy?

A

ITs produced by the placenta, actually got nothing to do with the liver or gall stones etc

30
Q

How does D-dimer change?

A

Rises, cos they’re hypercoagulable

Ergo we can’t use as we can’t know what normal is

31
Q

How do we get around the fact we can’t use a D-dimer to screen for PE?

A

Just have to send everyone we think might have it for a V/Q scan