How does cardiac output change during pregnancy?

How does cardiac output change during pregnancy?

• A. Increases 30 to 50% in the left lateral recumbent position
• B. Decreases 30 to 50%
• C. Remains unchanged
• D. Increases 60-80%

Answer: (A)

During pregnancy, cardiac output increases to meet the higher metabolic demands of both mother and fetus. This rise comes from an expanded blood volume (about a 40–50% increase by mid-pregnancy) and a faster heart rate, with stroke volume also contributing. Lying in the left lateral recumbent position helps maximize venous return by relieving uterine compression of the inferior vena cava, so the heart can pump more effectively. Together, these factors typically produce a 30–50% increase in cardiac output above the nonpregnant baseline when the patient is in that position. So, this larger, position-enhanced CO rise fits the physiological pattern of pregnancy. The other options aren’t consistent with what happens: CO does not decrease or remain unchanged, and a 60–80% increase would be greater than what is normally seen.

During pregnancy, cardiac output increases to meet the higher metabolic demands of both mother and fetus. This rise comes from an expanded blood volume (about a 40–50% increase by mid-pregnancy) and a faster heart rate, with stroke volume also contributing. Lying in the left lateral recumbent position helps maximize venous return by relieving uterine compression of the inferior vena cava, so the heart can pump more effectively. Together, these factors typically produce a 30–50% increase in cardiac output above the nonpregnant baseline when the patient is in that position.

So, this larger, position-enhanced CO rise fits the physiological pattern of pregnancy. The other options aren’t consistent with what happens: CO does not decrease or remain unchanged, and a 60–80% increase would be greater than what is normally seen.