SVC Syndrome

[Mom2littleangel]

My baby developed SVC syndrome after the PDA ligation. In my research, SVC syndrome is "uncommon and is a  complication following neonatal cardiac sugery". Is this complication uncommon for very premature babies?

[Yao Sun, MD, PhD]

PICC lines are usually inserted only with visualization of the superificial vein, then the thin flexible catheter is advanced within the vein to the large veins near the heart.  The patient is measured beforehand to know how far to advance the PICC line.

Blood clots are a known, although uncommon, complication of PICC lines.  When a clot is suspected, an ultrasound is usually performed to investigate the location and size of the clot.

[Mom2littleangel]

Can blood clots not be seen or found? When a PICC line is inserted, do the nurses or doctors need visual help to guide the line in or can they do it blindly? Thank you so much!

[Yao Sun, MD, PhD]

The chylothorax (build-up of lymphatic fluid around the lung) is most likely a complication of the SVC syndrome.  When the major blood vessels near the heart have blood clots, it can also restrict the flow of lymphatic fluid because much of the lymphatic fluid eventually drains into the large blood vessels.  The backup of lymphatic fluid then causes the chylothorax.

[Mom2littleangel]

What are the odds for premature babies to develop SVC syndrome and chylothorax? What could cause chylothorax? I'm not finding helpful information and I'm not understanding what I am reading on the internet. Thank you so much!

[Yao Sun, MD, PhD]

Although it is possible that the Superior Vena Cava (SVC) syndrome (obstruction of blood flow through the SVC) was caused by the PDA ligation, this is a rare complication.  The more common cause is blood clots from central venous lines, or special IVs that reach the deep veins near the heart such as the SVC.  Anytime there is a foreign body such as an IV in the blood stream, there is a risk for clot formation.

Depending upon the severity of the SVC syndrome, the neonatologists may choose to just observe your baby, or may choose to use medications to "anticoagulate" or prevent further blood clot from forming.  In some very severe cases, other medications can be used to actually attempt to break down the clot.  However, there is a risk of bleeding with these medications, so the physicians have to weigh the risks and benefits very carefully.