What is the expected increase in cardiac output when the uterus is displaced off the vena cava?

When the uterus is displaced off the vena cava, it relieves pressure on the inferior vena cava that the uterus exerts during the later stages of pregnancy. This allows for improved venous return to the heart, resulting in an increased preload. Consequently, this enhanced venous return leads to an increase in stroke volume, and as a result, cardiac output increases.

The expected increase in cardiac output when the pressure is alleviated from the vena cava is approximately 30%. This is significant because it highlights the importance of positioning in managing hemodynamic stability in pregnant patients, particularly in emergency situations. Proper positioning can dramatically affect cardiac output and overall maternal and fetal perfusion.

Other options indicate varying degrees of increase that do not align with current clinical findings. These discrepancies highlight the importance of recognizing that the physiological response in this situation is indeed substantial, but the increase observed when the uterus is displaced is commonly estimated around the 30% mark in clinical studies. Understanding this effect is crucial for healthcare providers managing care during pregnancy.