Pregnancy Flashcards
What does progesterone during pregnancy cause?
- smooth muscle relaxation
- decreased GI tract motility/constipation
- increased basal temperature
- bronchodilatation
- vasodilatation
- renal tract dilatation
How much does blood volume increase by in pregnancy at term?
45-50%
Why does haematocrit decrease during pregnancy?
Although there is an increase in red cell mass, there is a greater increase in plasma volume resulting in a net decrease in haematocrit
Why does cardiac output increase during pregnancy?
Increased stroke volume
When does aorto caval compression become clinically significant?
From 20 weeks gestation onwards
What is the normal PaCo2 in the 1st trimester?
It decreases to approx 4kPa due to progesterone.
Leads to respiratory alkalosis.
What happens to FRC at term?
Decreased to 80% of normal.
Leads to airway closure and rapid desaturation when supine
How much above normal does O2 consumption rise to in pregnancy?
35% above pre-preggo levels
What acts as a respiratory stimulant during pregnancy?
Progesterone and oestrogen both do.
What happens to gastric emptying and LOS tone during pregnancy?
Gastric emptying is unchanged (unless opioids given).
LOS tone is decreased due to smooth muscle relaxation.
What % of women suffer heartburn in pregnancy?
75-85% due to decreased LOS tone
When in pregnancy does an RSI become a requirement?
From 2nd trimester onwards
What are oxytocics used for?
Eg syntocinon
Used to induce labour, to those labouring making slow progress and after delivery at C-section to ensure uterine contraction and reduce intrauterine bleeding.
They can result in hypotension/tachycardia - give slowly.
Can warfarin cross the placenta?
Yes and is teratogenic so cannot be given during pregnancy.
Can glycopyrrolate cross the placenta?
No it’s a quaternary amine - so charged + cannot cross the placenta
