Trendelenburg Position

What is the Trendelenburg position?

The Trendelenburg position is a way of positioning you on an operating table or hospital bed for certain medical purposes. A 19th century surgeon named Friedrich Trendelenburg popularized it. Trendelenburg found that positioning a person on their back (supine) and angled slightly downward at the head (at least 15°) makes it easier for a surgeon to access their lower abdominal and pelvic organs.

Trendelenburg position variations

Healthcare providers also use several variations of the Trendelenburg position, including:

• Modified Trendelenburg position: The modified Trendelenburg position has your legs raised but leaves your head and back level. This position encourages blood flow to your heart and brain.
• Reverse Trendelenburg position: The reverse Trendelenburg position reverses the angle, raising your head 15 degrees over your feet. This provides better access to your upper abdominal organs.
• Steep Trendelenburg position: The steep Trendelenburg position increases the downward angle of your head to 30 degrees to 40 degrees. This position provides better access for robotic surgery on your pelvis.
• Trendelenburg position with hip flexion: The hip flexion bends your knees toward your chest. Adding hip flexion to the Trendelenburg position flattens the curve at the base of your spine.

What is the Trendelenburg position used for?

The most common uses for the Trendelenburg position are:

• Lower abdominal/pelvic surgery
• Central venous catheter placement

There are many organs in your lower abdomen. Your intestines, reproductive organs and urinary system are all smooshed together in there. Other organs sit just above them. Having your feet slightly elevated over your head allows the organs near the top of your abdominal cavity to slide away from the ones near the bottom. This gives your surgeon a little more room to work with those organs.

Another effect of gravity in the Trendelenburg position is that it encourages your blood to flow toward your upper body. This can be helpful for other medical purposes. One common purpose is to place a central venous catheter in your subclavian vein (in your upper chest) or your internal jugular vein (in your neck). Blood flooding into these veins expands them, making them easier to locate and puncture.

Other uses include:

• Distributing spinal anesthesia: If you have a spinal block, but it doesn’t numb you as high up as it needs to, your healthcare team might try the Trendelenburg position to help distribute the medicine. Adding hip flexion helps prevent it from pooling in the curve of your lumbar spine.
• Dynamic CT myelography: A dynamic CT myelogram is a contrast-enhanced CT scan that your healthcare providers use to look for cerebrospinal fluid leaks. The Trendelenburg position helps distribute the contrast solution through your spine.
• Treatment of hypovolemic or anaphylactic shock: If you go into shock, sometimes, your care team will use the Trendelenburg position to help return blood flow to your heart and organs. But this has risks for some people and is no longer routinely recommended.

What are the potential risks or side effects of the Trendelenburg position?

The risks and side effects of the Trendelenburg position relate to the impact of gravity on your upper body. These risks increase with longer procedures, steeper angles and greater body mass. Healthcare providers must pay close attention to these factors when using the position. When appropriate, they use a modified Trendelenburg to reduce the effects. Or they use reverse Trendelenburg to reverse them.

Risks include:

• Slipping injuries: Healthcare providers must take care to secure you to the operating table so you don’t slide. Sliding even a little could cause skin injury. Sliding all the way off could cause head injury. Slipping could also interfere with correct placement during robotic surgery.
• Brachial plexus injury: In the past, healthcare providers used shoulder braces to help prevent slipping in the Trendelenburg position. But pressure from these braces could injure your brachial plexus nerves. Newer positioning devices include foam or microbead pads and gel overlays.
• Eye injury: Your eyes contain fluids (aqueous humor and vitreous humor) that create pressure inside them. If gravity raises this pressure too much, there’s a risk it could cut off the blood supply to your optic nerve, causing vision loss. Healthcare providers must monitor this pressure.
• Respiratory depression: The weight of your abdominal organs against your diaphragm puts pressure on your lungs. Meanwhile, the drift of blood flow toward your head raises the pressure in your veins. This, combined with other risk factors, can lead to respiratory depression.
• Pulseless electrical activity: The weight of internal organs against your heart can, in severe cases, compress your heart and stop blood from flowing out of it. Your heart continues to beat, and the heart monitor appears normal, but there’s no blood or pulse. While incredibly rare, this can cause cardiac arrest.
• Increased intracranial pressure (ICP): Gravity in the Trendelenburg position can cause blood and cerebrospinal fluid to pool in your head. This can raise your intracranial pressure. This is risky if you have other risk factors for ICP, like a head injury or acute low blood pressure from shock.

Risk factors for complications

You may be more at risk of complications from the Trendelenburg position if you have:

• A longer procedure
• A steeper Trendelenburg angle
• High body mass index (BMI) or pregnancy
• Preexisting cardiovascular disease or pulmonary risk factors
• Preexisting eye disease, like glaucoma or hypertensive retinopathy
• Preexisting risk factors for ICP, like brain swelling or brain bleeding

Healthcare providers weigh these risks against your personal needs when making treatment decisions. Many medical procedures have potential risks, but they also have potential benefits that may outweigh the risks. Care teams take careful precautions to prevent the known risks. In some cases, they might use the Trendelenburg position only briefly, or they might build in regular breaks from it.

What happens after a procedure in the Trendelenburg position?

If you’re in Trendelenburg position for a longer procedure, your body will need a little time to readjust afterward. You may be swollen with fluid in your face or around your throat. If you had a breathing tube installed for the procedure, your healthcare team will monitor you carefully before removing it. They’ll want to make sure you can breathe normally on your own first.

How long does it take to recover from Trendelenburg position?

If you’re only in the Trendelenburg position for a few minutes, you probably won’t need to recover. But if you’re in it for a longer procedure, it may take a few minutes to hours before you feel normal again. You may feel lightheaded or dizzy afterward. If you had surgery, you’re probably also recovering from the effects of anesthesia, which may have similar effects. Try to just take it easy for the rest of the day.