Physiology in pregnancy Flashcards
What are mechanical changes in pregnancy?
Big bump over abdomen
Curvature of the spine changes to make up for balance
How does metabolism change in pregnancy?
Metabolism is greatly increased and ketones are produced earlier in starvation mode - begin being produced at 12 hours
What are general symptoms felt throughout pregnancy?
Fatigue - particularly in early pregnancy Heartburn/reflux Oedema Weight gain General state of immunosuppression
What happens to breasts in pregnancy?
They increase in size and there is an increase in glandular tissue
Increased pigmentation of the nipple and areola
Montgomery tubercules appear on the areola
What happens to thyroid activity in pregnancy?
There is an increase in thyroid binding globulin and an overall increase in T3 and T4 but free levels remain the same
What is colostrum?
Fluid produced briefly after birth from the breasts which is like milk but has higher protein and lower fat, as well as antibodies that can be passed on to the baby
What are Montgomery tubercles?
Glands around the areola that can be seen from the skin surface which produce lipoid fluid which keeps the nipple lubricated and protected
When would a woman wan to farm colostrum?
If a baby is born very prematurely or if there is cleft palate or another condition that prevents them from feeding from the breast they can be fed from a bottle
What happens to cardiac output in pregnancy?
It is increased by 40-50%
What happens to heart rate in pregnancy?
It increases
Why should a pregnant woman never be resuscitated supine?
Cardiac output is reduced by 25% when supine so they will never be resuscitated
Why is cardiac output reduced in pregnancy when supine?
The fetus compresses the IVC leading to reduced venous return
What happens to plasma volume in pregnancy?
Increases by 50%
Why does heart rate increase so much during labour?
Pain of labour causes an increase in heart rate as well as release of catecholamines which also increases HR as well as blood pressure
What is the most common cause of death in pregnancy?
Heart disease
Why does cardiac output increase by 80% in the 1st hour after delivery?
Blood from the placentouteral circulation comes back into systemic circulation causing enormously more venous return
Why is coronary artery disease becoming more common and why is this important for pregnancy?
Obesity and smoking are more common and this is important because coronary artery disease causes an ischaemic event postpartum
When do cardiovascular changes return to normal after pregnancy?
After about 3 months usually
When does heart rate return to normal after pregnancy?
Over about 2 weeks
What happens to alveolar ventilation in pregnancy?
It increases via increase in tidal volume and respiratory rate
What is the increase in oxygen demand during pregnancy?
20%
What happens to partial pressure of CO2 during pregnancy?
It decreases
What happens to the urinary collecting system in pregnancy?
There is great dilatation
What happens to GFR?
Increases by 50% with an increase in creatinine clearance
What changes can be seen in urine during pregnancy?
Increased protein excretion
May have microscopic haematuria
Glycosuria
Decrease in urea and creatinine
Why is it important to know creatinine and urea are decreased in pregnancy?
Because a pregnant woman with creatinine in a normal non-pregnant range is probably in renal failure
What changes haematologically in pregnancy?
Decrease in haemoglobin, haematocrit, red cell count, and platelet count
Increase in white cell count and plasma volume
What happens to albumin levels in pregnancy?
They decrease
What happens to LFTs in pregnancy?
They decrease
What happens to alkaline phosphate in pregnancy?
It greatly increases due to the placenta
Why can’t a D dimer measurement be used to determine clotting value in pregnant women?
It is almost always raised by an unpredictable amount
What happens to drug metabolism during pregnancy?
It is greatly increased meaning dosages must change
What causes gestational diabetes?
Human placental lactogen causes an increase in insulin resistance
