Internal Iliac Bleeding
Bleeding from deep pelvic vessels, often after a pelvic fracture
Quick Facts
- Type: Pelvic vascular bleeding (emergency)
- Common cause: Pelvic fracture, pelvic trauma
- Main risk: Hidden, heavy internal blood loss
- Treatment: Embolization, pelvic stabilization, surgery
Overview
The internal iliac arteries, sometimes called the hypogastric arteries, and their many small branches supply blood to the organs, muscles, and bones of the pelvis. Internal iliac bleeding refers to blood loss from these vessels, usually deep within the pelvis. It is one of the most common and dangerous sources of bleeding after a serious pelvic injury.
Because these vessels are surrounded by bone and tissue, bleeding from them is often hidden and can be difficult to control. A large amount of blood can be lost into the pelvis without any visible external bleeding, so this is a medical emergency that requires rapid recognition and treatment.
Symptoms
Signs of internal iliac bleeding are largely those of internal blood loss and shock:
- Severe pelvic or lower abdominal pain
- Swelling, fullness, or bruising of the pelvis, groin, or upper thighs
- Dizziness, weakness, pale and sweaty skin
- Rapid heartbeat and rapid breathing
- Low blood pressure or fainting
- Confusion or reduced alertness as blood loss worsens
These are emergency signs. Because the bleeding is internal, the amount lost can be much greater than it appears, so any signs of shock after a pelvic injury need immediate care.
Causes
Internal iliac bleeding most often follows trauma to the pelvis. Common causes include:
- Pelvic fractures: The most frequent cause; broken bone edges tear the small pelvic vessels.
- Penetrating trauma: Stab and gunshot wounds.
- Surgical or procedural bleeding: Pelvic operations or childbirth-related injuries can cause bleeding from these vessels.
- Crush injuries: Severe compression of the pelvis.
Most bleeding after a pelvic fracture comes from these small veins and arteries rather than a single large vessel, which makes it diffuse and hard to control.
Risk Factors
- High-energy pelvic trauma and unstable pelvic fractures
- Penetrating abdominal or pelvic wounds
- Pelvic surgery or complicated childbirth
- Blood-thinning medication or bleeding disorders
- Crush injuries to the pelvis
Diagnosis
Diagnosis happens quickly as part of trauma care:
- CT angiography: Identifies the site of active bleeding and the extent of pelvic injury.
- Physical exam: Assessing pelvic stability and signs of shock.
- Bedside ultrasound and blood tests: To detect internal bleeding and track blood loss.
- Angiography: An X-ray of the pelvic vessels that can both locate and treat the bleeding.
Doctors also look for other injuries, because pelvic bleeding rarely occurs alone after major trauma.
Treatment
Treatment aims to stop the bleeding and support the circulation as quickly as possible.
- Resuscitation: Fluids and blood transfusions to treat shock.
- Pelvic stabilization: A binder or external frame compresses the pelvis to reduce bleeding from fractured bone.
- Angiographic embolization: Through a catheter, doctors block the bleeding vessels, which is often very effective for internal iliac bleeding.
- Pelvic packing or surgery: Packing the pelvis or operating may be needed when bleeding cannot be controlled otherwise.
- Treating other injuries: Fractures and other damage are managed at the same time.
Rapid, coordinated treatment greatly improves survival from this serious bleeding.
Prevention
- Always wear a seatbelt and use protective equipment
- Follow safety rules to prevent high-energy pelvic injuries
- Manage bleeding disorders and review blood thinners with your doctor
- Seek immediate care after any severe pelvic injury
When to See a Doctor
Internal iliac bleeding is a life-threatening emergency. Call emergency services immediately after a pelvic injury if there are signs of:
- Dizziness, weakness, pale or sweaty skin
- Rapid heartbeat and breathing
- Severe pelvic or lower abdominal pain
- Confusion, fainting, or rapidly worsening condition
Because the bleeding is internal, the person may appear less injured than they are. Keep them still and warm, and do not delay seeking emergency care.
Frequently Asked Questions
What is internal iliac bleeding?
It is bleeding from the internal iliac vessels and their small branches deep in the pelvis. This is one of the most common sources of severe, often hidden, blood loss after a serious pelvic injury such as a fracture.
Why is this type of bleeding so dangerous?
The vessels are surrounded by bone and tissue, so a large amount of blood can collect inside the pelvis with little or no visible external bleeding. The blood loss can quickly cause shock, making it a medical emergency.
How is internal iliac bleeding stopped?
Treatment includes fluids and blood for shock, a pelvic binder to compress fractured bone, and angiographic embolization, in which a catheter is used to block the bleeding vessels. Pelvic packing or surgery may be needed if bleeding continues.
What are the warning signs after a pelvic injury?
Dizziness, weakness, pale or sweaty skin, a racing heartbeat, severe pelvic pain, and fainting are warning signs of internal bleeding. Because it is hidden, a person can be seriously injured even without obvious external bleeding.
What should I do while waiting for help?
Call emergency services immediately, keep the person still and warm, and avoid unnecessary movement of the pelvis. Quick treatment is critical, so do not wait to see if the person improves on their own.
References
- American College of Surgeons. Pelvic Fracture and Hemorrhage.
- Society for Vascular Surgery. Pelvic Vascular Trauma.
- MedlinePlus, U.S. National Library of Medicine. Internal bleeding.
- National Heart, Lung, and Blood Institute (NHLBI). Bleeding and shock.