Physiological changes of pregnancy (304/1700)

Which of the following is NOT a physiological change during pregnancy?
a. Tidal volume 500ml
b. RBC vol 1.64L
c. Cardiac output 6.5L/min
d. Uterus weight 1.1kg
e. ESR up by 4x































answer: A
Respiratory changes in pregnancy

• Mild respiratory alkalosis that helps CO2 diffuse across the placenta from fetal to maternal circulation
• No change in VC and FEV1
• Decreased TLC, FRC, and RV
• Tidal volume increases by about 200 ml (normal is 500ml)

Heart
Cardiac output increases by 30-50% with 15% increase in heart rate and 25-30% increased stroke volume. normal 4.8L/min
Diastolic and systolic blood pressure tend to fall during mid pregnancy and then return to normal by week 36.