Iliac Vein Injury

What to do now

Call 911 or your local emergency number for any penetrating wound to the lower body or a serious pelvic injury. Keep the person lying flat and still, press firmly on any visible bleeding wound, keep them warm, and do not give food or drink. Do not remove impaled objects. Internal pelvic bleeding cannot be controlled with first aid, so speed to a trauma center is what matters.

Anatomy: why these injuries are so serious

The common iliac veins form where the external iliac vein (draining the leg) joins the internal iliac vein (draining the pelvic organs). Left and right common iliac veins merge at about the level of the navel to form the inferior vena cava. They lie deep in the pelvis, close to the spine and directly behind the iliac arteries, and they have thin walls.

Because the veins are deep, bleeding collects in the space behind the abdominal lining (a retroperitoneal hematoma) and inside the pelvis, which can hold several liters. Veins do not clamp down on themselves the way arteries can, and they are difficult to reach and repair. Iliac vein injuries carry a high death rate, especially when the iliac artery is injured at the same time.

Causes

• Penetrating trauma: gunshot and stab wounds are the most common cause in civilian trauma centers.
• Blunt trauma: unstable pelvic fractures from car crashes, motorcycle accidents or falls can tear the veins and the network of smaller pelvic veins.
• Surgical (iatrogenic) injury: - Anterior lumbar spine surgery, where the veins must be moved aside to reach the spine - Instruments passing too far forward through a disc during back surgery - Hip replacement and pelvic or gynecologic cancer surgery - Catheter and stent procedures through the groin

Symptoms and signs

The picture is dominated by blood loss:

• Signs of hemorrhagic shock: fast heartbeat, low blood pressure, pale, cold and clammy skin, rapid breathing, confusion and reduced urine
• Pain in the pelvis, groin, lower back or flank
• Bruising over the flank, groin or perineum, which may appear hours later
• A wound in the lower abdomen, buttock or groin
• Swelling of one leg if the vein is narrowed or blocked

During surgery, an iliac vein injury shows as sudden dark bleeding or an unexplained drop in blood pressure.

Diagnosis

In an unstable patient, there is no time for scans. The trauma team resuscitates the patient, may wrap the pelvis with a binder, and moves straight to surgery or angiography. A FAST ultrasound at the bedside looks for blood in the abdomen. In a stable patient, a CT scan with contrast in the venous phase shows the hematoma, active bleeding and associated fractures.

Treatment

1. Resuscitation: blood transfusion in balanced ratios of red cells, plasma and platelets, tranexamic acid when given early, and keeping the patient warm.
2. Damage control surgery: direct pressure and packing of the pelvis to stop bleeding, with a planned return to the operating room once the patient is stable.
3. Repair options: - Suturing a simple tear - Patch repair or a vein graft - Ligation (tying off the vein): often life-saving in unstable patients. The body usually develops collateral veins, but leg swelling can follow. - Covered stent graft placed through a catheter, increasingly used for surgical injuries and selected trauma cases
4. Pelvic stabilization with an external fixator or binder when a fracture is present.

Complications

• Deep vein thrombosis and pulmonary embolism: blood clots are common after pelvic venous injury. Blood thinners are started once bleeding is controlled.
• Long-term leg swelling, heaviness and skin changes (post-thrombotic syndrome)
• Compartment syndrome of the leg after ligation
• Infection and organ failure after massive transfusion

Outlook

Isolated injuries that are recognized quickly, especially surgical injuries repaired on the spot, have a good outlook. Penetrating injuries with combined artery and vein damage, or massive pelvic fractures, carry a substantial risk of death. Survivors may need compression stockings and follow-up with a vascular surgeon for leg swelling.

Frequently asked questions

How serious is an iliac vein injury?

Very serious. The iliac veins carry a large volume of blood and lie deep in the pelvis where bleeding is hard to see and hard to control. Death rates are significant, particularly when the iliac artery is injured too. Rapid transport to a trauma center and immediate surgery are life-saving.

Can the iliac vein be injured during spine surgery?

Yes. In anterior lumbar fusion, the surgeon must move the iliac veins aside to reach the spine, and they can tear. Rarely, instruments in posterior disc surgery pass through the front of the disc. Surgeons watch for sudden bleeding or a drop in blood pressure and repair the vein immediately.

Can you live without an iliac vein?

Usually, yes. When an iliac vein must be tied off to save a life, blood finds other routes back to the heart through collateral veins. Many people do well, but some develop long-term swelling, heaviness or pain in that leg, managed with compression and elevation.

Why are blood clots common after iliac vein injury?

Damage to the vein wall, slow blood flow after repair or narrowing, immobility and major trauma all promote clotting. Clots can travel to the lungs. Once bleeding is controlled, doctors give blood thinners and use compression devices to lower the risk.