Where it is
The superior vena cava collects blood from the head, neck and arms; the inferior vena cava runs up beside the aorta to collect blood from the legs, pelvis and abdomen.
What it does
Return of blood through the venae cavae sets the preload of the right heart.
Clinical relevance
- Central venous catheters (PICC lines, central lines) end in the lower superior vena cava near the right atrium.
- In late pregnancy, lying supine compresses the inferior vena cava and causes hypotension (supine hypotensive syndrome).
- Superior vena cava syndrome (often from lung cancer) causes facial and arm swelling.
Nursing focus
- Position a pregnant client on her left side to relieve pressure on the inferior vena cava.
- Confirm central line tip placement by X-ray before first use, per facility policy.