Risks and Complications of Pediatric ECMO — What Parents Should Watch For

Medicine Made Simple Summary

ECMO can save a child’s life, but it also carries risks. The most common complications include bleeding, clotting in the ECMO circuit, infections, lung or heart challenges, kidney strain, and problems related to medications used to thin the blood. Parents should watch for signs such as unexpected bleeding, swelling, fever, changes in breathing, or sudden changes in behavior. Close monitoring by the PICU team helps detect issues early. Understanding these risks prepares families for what may happen while ECMO supports their child.

Why It Helps to Understand ECMO Risks Before and During Treatment

Parents often learn about ECMO during one of the most frightening moments of their child’s medical journey. The focus is on survival and support. But as the days go by, families start to wonder about complications, long-term effects, and what signs they should pay attention to. Understanding the risks does not make ECMO more frightening. Instead, it helps parents feel informed and involved in the child’s care.

ECMO is a powerful life-saving therapy. It allows a child’s heart or lungs to rest when they are too weak to function. But because ECMO involves placing large tubes in blood vessels, moving blood outside the body, and using strong medications, complications can occur. The medical team monitors every detail to detect problems early, but knowing what might happen prepares families and helps them ask the right questions.

A Short Review: What ECMO Does and Why Complications Occur

How ECMO Works

ECMO temporarily replaces the work of the heart, the lungs, or both. It pumps blood out of the body, adds oxygen, removes carbon dioxide, and returns the blood. This gives organs time to heal.

Why Risks Exist

ECMO is complex. Blood flows through an artificial circuit. Medications thin the blood to prevent clots. Tubes enter major blood vessels. These factors create specific risks that the PICU team manages every minute.

Risk 1: Bleeding

Why Bleeding Happens on ECMO

To prevent clots inside the ECMO circuit, doctors give blood-thinning medications. These medications help keep the circuit safe but increase the chance of bleeding. 

• Bleeding can occur
• Around the cannula sites
• In the mouth or nose
• In the stomach or intestines
• From surgical wounds

The Most Concerning Type: Brain Bleeding

One of the most serious complications is bleeding in the brain. This is rare but closely monitored. Regular head ultrasounds or brain imaging help detect problems early.

What Parents May Notice

Parents may see small oozing at cannula sites. This is common. Larger amounts of bleeding are taken very seriously. Nurses watch constantly for changes.

Risk 2: Clotting

Why Clotting Happens Even With Blood Thinners

The ECMO circuit—tubes, pump, and oxygenator—can trigger clot formation. Even while receiving blood thinners, the body may create clots as a natural response to the foreign materials.

Where Clots May Form

Clots may form

• In the tubing
• In the oxygenator
• Near the cannulas
• Within the child’s bloodstream

How Clots Are Detected

The team regularly checks pressures and flows in the circuit. They also use blood tests to measure how well the child’s blood is clotting. If clots develop in the oxygenator, it may need to be replaced.

Risk 3: Infection

Why Infection Is a Concern on ECMO

ECMO requires large cannulas placed into major blood vessels. The longer a child stays on ECMO, the greater the risk of infection. Children in the ICU also receive many medications and procedures, increasing vulnerability.

Types of Infection

Infections may involve

• Cannula sites
• Bloodstream
• Lungs
• Surgical sites if the child has recently had surgery

Signs Parents Should Watch For

• Fever
• Increased swelling
• Redness near cannula sites
• Sudden drop in blood pressure

The team uses antibiotics and strict hygiene practices to minimize risk.

Risk 4: Lung Complications

Lung Collapse or Overinflation

The lungs often rest while on ECMO. Because they are not working as hard, they can sometimes collapse or retain fluid. The ventilator is used at low settings to prevent strain, but problems can still occur.

Pulmonary Hemorrhage

Rarely, bleeding may occur inside the lungs. This can happen due to blood thinners or inflammation. It is treated quickly with adjustments to medication and ventilator support.

What Parents May See

• Changes in ventilator settings
• Bloody fluid from breathing tubes
• More frequent suctioning

The care team explains these changes as they occur.

Risk 5: Heart Complications

Changes in Heart Function

In children on VA ECMO, the heart may take time to recover. Sometimes the heart becomes weaker before it becomes stronger. ECMO reduces the heart’s workload, but complications can still happen.

Movement of the Cannulas

Because cannulas are placed near the heart or large vessels, movement can affect blood flow. The team checks placement with ultrasounds or X-rays.

Heart Rhythm Problems

Some children develop irregular heart rhythms. Medications and monitoring help stabilize the situation.

Risk 6: Kidney Stress

Why Kidney Problems Occur

When the heart or lungs fail, other organs become stressed. The kidneys may not filter blood well, leading to fluid buildup. ECMO itself does not harm the kidneys, but the child’s underlying illness might.

How the Team Supports the Kidneys

If the kidneys are struggling, the team may use dialysis or adjust medications. Many children recover kidney function after ECMO.

Risk 7: Neurologic Complications

Why the Brain Is Closely Monitored

The brain is sensitive to changes in oxygen, blood flow, and bleeding. ECMO can affect all three. Babies and young children are especially vulnerable.

Possible Complications

• Bleeding
• Stroke
• Seizures
• Temporary changes in behavior or alertness

How the Team Monitors the Brain

• Daily examinations
• Head ultrasounds
• EEG monitoring for seizures
• Imaging when needed

Parents are informed immediately if there are any concerning signs.

Risk 8: Fluid Imbalance and Swelling

Why Swelling Occurs

Critical illness causes inflammation. ECMO adds additional fluid to the system. Children may look puffy, especially around the eyes and arms.

Managing Swelling

The team may give diuretics to remove extra fluid or adjust ECMO settings to improve circulation.

Risk 9: Oxygenator Failure

What the Oxygenator Does

The oxygenator adds oxygen to the blood and removes carbon dioxide. Over time, it can weaken or clog.

How Doctors Detect Failure

• Increasing pressure inside the circuit
• Decreased oxygen levels
• Changes in blood gases

If needed, the oxygenator is replaced quickly and safely.

Risk 10: Skin and Pressure Injuries

Why Skin Breakdowns Occur

Children who are sedated cannot move on their own. The team repositions them regularly, but pressure sores can still develop.

Prevention Strategies

• Soft padding under pressure points
• Regular repositioning
• Skin checks throughout the day

How the PICU Team Reduces Risk

• Continuous Monitoring: A child on ECMO is monitored minute by minute. Machines track heart rate, blood pressure, oxygen levels, and circuit pressures. Nurses and perfusionists stay close by at all times.
• Daily Adjustments: Medications are changed daily based on blood test results. Ventilator settings, ECMO flow, and nutrition plans are adjusted as needed.
• Advanced Imaging and Testing: X-rays, ultrasounds, and blood tests help detect complications early.
• Rapid Response: The ECMO team can respond quickly to any sudden changes. This rapid action prevents small issues from becoming serious.

What Parents Should Watch For at the Bedside

Parents can help by observing and reporting changes such as

• New bleeding
• Sudden swelling
• Changes in alertness
• Strange movements or twitching
• Changes in skin color
• Sudden drops in blood pressure shown on the monitor
• Fever or chills

Although parents are not responsible for monitoring equipment, they often notice subtle changes that can help the team respond quickly.

Understanding Risk Does Not Mean Losing Hope

Many children on ECMO recover well. Complications are common, but the entire PICU team works together to manage them. Knowing the risks helps parents feel prepared, ask stronger questions, and understand the decisions made around their child’s care.

ECMO is used only when the chance of recovery is real. Families should remember that ECMO is offered because the medical team believes it can help the child survive a critical illness.

Conclusion

If your child is on ECMO or may need ECMO soon, speak openly with your care team about risks and warning signs. Ask what they are watching for, how they manage complications, and how you can stay informed. Understanding the risks helps you feel more prepared and more connected to your child’s care during this challenging time.