Internal Iliac (Pelvic) Artery Bleeding

What to do at the scene

1. Call 911 or your local emergency number.
2. Keep the person lying still and warm. Do not let them walk if a pelvic injury is possible.
3. Do not rock or press on the pelvis to "check" it.
4. Control any visible external bleeding with firm pressure.
5. Emergency crews may wrap a pelvic binder or a sheet around the hips to stabilize the pelvis and slow bleeding.

The internal iliac artery

The aorta divides in the lower belly into the two common iliac arteries. Each splits into an external iliac artery, which supplies the leg, and an internal iliac artery (also called the hypogastric artery), which supplies the pelvic organs (bladder, uterus, rectum, prostate), the buttock muscles and the pelvic walls. Its many branches run close to the bones of the pelvis, so they are easily torn when the pelvis breaks.

Causes

Pelvic fractures

Unstable pelvic ring fractures from high-energy trauma are the most common cause. Most bleeding from pelvic fractures comes from veins and broken bone, but arterial bleeding from internal iliac branches, such as the superior gluteal and internal pudendal arteries, causes the most rapid, life-threatening blood loss. See pelvic fracture.

Childbirth

Severe postpartum hemorrhage, uterine rupture, placenta accreta and tears during delivery can involve uterine and other internal iliac branches.

Aneurysms

Iliac artery aneurysms (weak, ballooned sections of artery wall) can rupture, often together with an abdominal aortic aneurysm. Rupture causes sudden pain and collapse.

Other causes

• injury during pelvic, hip or spine surgery
• penetrating trauma such as stab or gunshot wounds
• tumors eroding into vessels
• bleeding disorders or anticoagulant medicines, which worsen bleeding from any cause

Symptoms and signs

• pain in the pelvis, lower belly, groin, hip, lower back or buttock
• swelling and bruising in the groin, buttock, perineum, scrotum or labia
• blood in the urine or from the rectum or vagina with some injuries
• signs of hemorrhagic shock: rapid pulse, low blood pressure, fast breathing, pale or mottled cold skin, thirst, anxiety, confusion and reduced urine

Because the blood collects in the space behind the abdominal lining (a retroperitoneal hematoma), large losses can occur with few outside signs.

Diagnosis

• Primary trauma survey: checking airway, breathing, circulation and pelvic stability.
• Pelvic X-ray in the trauma bay to identify unstable fractures.
• Bedside ultrasound (FAST): looks for blood in the abdomen, though it misses bleeding behind the abdomen.
• CT angiography: shows fractures and active bleeding ("contrast blush") from specific arteries.
• Catheter angiography: confirms the bleeding vessel and allows immediate treatment.
• Blood tests: blood count, clotting and lactate, plus blood typing for transfusion.

Treatment

• Resuscitation: rapid transfusion of blood products in balanced ratios (massive transfusion protocol), tranexamic acid in trauma, and keeping the patient warm.
• Pelvic binder: compresses an unstable pelvis to reduce its volume and limit bleeding.
• Angioembolization: an interventional radiologist passes a catheter through an artery in the groin or wrist into the bleeding branch and blocks it with coils, particles or plugs. This is highly effective for arterial pelvic bleeding.
• Preperitoneal pelvic packing: a surgeon packs gauze around the bladder to control mostly venous bleeding, often used in unstable patients.
• REBOA: a balloon in the aorta temporarily controls bleeding in some trauma centers.
• External or internal fixation of the fractured pelvis.
• Surgical repair or ligation of the artery, sometimes in obstetric hemorrhage.
• Aneurysm repair with a stent graft or open surgery.

Complications

• hemorrhagic shock and death if not controlled
• organ failure from prolonged shock
• after embolization: buttock muscle pain or damage, and rarely bladder, bowel or nerve problems, and erectile dysfunction
• infection of the blood collection
• blood clots during recovery

Outlook

Outcome depends on the severity of injuries, how much blood is lost, and how quickly bleeding is controlled. Trauma systems with rapid access to embolization and surgery have improved survival. Recovery from major pelvic fractures takes months and often involves rehabilitation.

Frequently asked questions

What is internal iliac bleeding?

It is bleeding from the internal iliac artery or its branches, which supply the pelvis and pelvic organs. It usually follows a severe pelvic fracture, childbirth complications, aneurysm rupture or surgery. Blood collects deep in the pelvis, so it may be hidden until shock develops.

How is pelvic arterial bleeding stopped?

Doctors stabilize the pelvis with a binder, give blood transfusions, and stop the bleeding with angioembolization, where a catheter blocks the bleeding vessel from inside. Surgical packing, repair or ligation are used when needed.

Can you live without an internal iliac artery?

Yes, in most cases. The pelvis has many connecting vessels, so one internal iliac artery can be blocked or tied off without losing blood supply to the pelvis. Blocking both carries a higher risk of buttock pain and other complications.

What are the signs of internal bleeding after a pelvic injury?

Warning signs are worsening pelvic, groin or back pain, swelling and bruising, along with a fast pulse, dizziness, pale or clammy skin, confusion and fainting. These signal significant blood loss and need emergency care.