Take Time to Stabilize Kidney Function Before Listing for Heart or Lung Transplant

A special report by the International Society for Heart and Lung Transplantation (ISHLT) is raising awareness of the need to stabilize patients’ kidney function before heart or lung transplantation to reduce mortality after surgery.

Taking time to stabilize kidneys may seem to contradict the urgency in listing critically ill patients for transplant. However, taking more than two weeks to recover kidney function before surgery is often worth the delay, says the report’s lead author Eileen Hsich, MD, Medical Director of Heart Transplantation at Cleveland Clinic.

“We rush to transplant when patients are critically unstable because we want to rescue them, have confidence that reversible kidney dysfunction will go away after transplant, and think it is ‘no big deal’ to be on dialysis after transplant since it will be temporary,” she says. “Unfortunately, we lose one-third of those patients.”

According to the 2025 ISHLT report published in The Journal of Heart and Lung Transplantation, mortality is greater than 30% when dialysis is needed while patients are still in the hospital after thoracic transplant (“early dialysis”). While this is a new finding in pediatric lung transplant, it reinforces earlier research in adult lung transplant as well as adult and pediatric heart transplant.

Despite existing literature, the poor outcomes associated with early dialysis after transplant are not widely acknowledged, Dr. Hsich says.

“We need to get the word out to more physicians in the transplant community: Kidney problems kill people — the people to whom we’ve just given valuable donor organs,” she emphasizes. “And it’s not just a U.S. problem. It’s global.”

Don’t count on heart transplant to recover a kidney

Why isn’t the importance of stabilizing kidney function before transplantation more widely known? Because cardiologists successfully care for patients with cardiogenic shock all the time yet may not realize the difference when surgery is involved, explains Dr. Hsich.

“A patient’s kidneys may have been compromised due to low blood pressure caused by a failing heart or lung,” she says. “Common belief is that the kidney will recover once the heart or lung is replaced. But it’s not that simple.”

The low blood pressure before surgery is only the first blow to a kidney. Transplant surgery, including the use of anesthesia that can destabilize blood pressure, is a second blow.

In addition, the infusion of fluids during surgery creates more work for kidneys.

“Kidneys in a healthy person would struggle to clear all of that extra fluid,” Dr. Hsich says. “We can’t expect a kidney that is compromised to perform better after surgery than a healthy kidney would on a normal day.”

And post-transplant dialysis may not be the easy fix, she notes. After transplant, patients are immunocompromised and at higher risk of infection. Adding a catheter to facilitate dialysis increases that risk.

On the contrary, patients on dialysis before transplantation — who, thus, had more stable kidney function leading up to surgery — have better outcomes after transplantation, according to the ISHLT report.

“I’m not saying that if kidney function is bad, you should withhold transplant, but if there’s a window of opportunity to recover the patient, it’s important to do so,” Dr. Hsich says. “That’s what we do at Cleveland Clinic. We attempt to get the kidneys (and liver) as strong as possible before listing a patient for heart transplant. It’s likely one of the reasons our transplant outcomes are among the best in the world.”

Cleveland Clinic’s patient survival rate unadjusted after heart transplant is 96.9% at one year and 87.3% at three years.

“Using all our tools and resources to help patients normalize their organ function prior to surgery plays a big part in achieving those results,” says Michael Tong, MD, MBA, Director of Cardiac Transplantation and Mechanical Circulatory Support at Cleveland Clinic.

“When the heart is failing, the kidneys are compromised, as are the liver, the brain and other organs,” he says. “To help the failing heart, we may utilize a temporary mechanical pump to normalize blood flow to the body and give the patient and organs an opportunity to improve before transplantation. In other situations, we may recommend a left ventricular assist device, which the patient may live with for many years before having a transplant.”

Adds Amanda Vest, MBBS, Section Head of Heart Failure and Recovery at Cleveland Clinic, “We are hopeful that ongoing research will enable us to refine strategies for improving kidney function in the setting of cardiogenic shock and around the transplant surgery. One example is the ongoing evolution in the temporary pumps that mechanically support weak hearts.”

Early dialysis and survival after heart transplant

In the ISHLT report, a study group assessed records in the International Thoracic Organ Transplant Registry.

Out of more than 50,000 adults and nearly 8,000 pediatric patients worldwide who had a heart transplant between 1994 and 2018, 9.9% of adults and 6.3% of pediatric patients required early dialysis. These patients had much lower survival rates than the patients who did not need early dialysis.

The biggest risk factor associated with early dialysis was renal dysfunction at the time of transplant. The lower the estimated glomerular filtration rate (eGFR), the higher the risk.

Other risk factors included:

• Underlying heart disease in adults
• Congenital heart disease in pediatric patients
• Use of mechanical ventilation or extracorporeal membrane oxygenation (ECMO)
• Longer ischemic time
• Older donor age

Early dialysis and survival after lung transplant

Out of more than 34,000 adults and nearly 1,200 pediatric patients worldwide who had a lung transplant between 1994 and 2018, 6.1% of adults and 5.6% of pediatric patients required early dialysis. As with the heart transplant cohort, lung transplant patients needing early dialysis had much lower survival rates than those who did not need early dialysis.

Again, the biggest risk factor associated with early dialysis was renal dysfunction at the time of transplant. The lower the eGFR, the higher the risk.

Other risk factors in adults included:

• Nonchronic obstructive heart disease underlying lung disease
• Use of mechanical ventilation or ECMO
• Higher BMI
• Higher bilirubin
• Diabetes mellitus
• Longer ischemic time
• Older donor age

“This analysis highlights the fact that high mortality associated with early dialysis in thoracic patients is of concern and that providers should consider early kidney transplantation using safety net allocation to try to mitigate the impact of renal replacement therapy,” says Marie Budev, DO, MPH, Medical Director of Lung Transplantation at Cleveland Clinic.

How to prevent dialysis after transplant surgery

Approximately half of all heart or lung transplant recipients with early dialysis die within one year of surgery, summarizes Dr. Hsich. That includes children who were born with healthy kidneys. Even they have poorer outcomes when their transplant occurs in the setting of renal failure.

“How can we prevent dialysis after transplant surgery?” asks Dr. Hsich. “It starts with making the kidneys healthier before surgery. Even small improvements in abnormal eGFR can significantly reduce risk of dialysis after surgery.”

However, the current allocation system defines medical urgency based on the severity of heart or lung disease but not end-organ dysfunction. The system allows a two-week window for getting critically ill patients transplanted once they are on the waiting list before having to change strategy towards a durable heart pump.

“Urgency is necessary, but we still need some leniency for stabilizing organs that have been acutely affected by heart or lung failure,” Dr. Hsich says. “It’s important to take time to recover organs, if possible, since survival after surgery is poorer when we don’t. We can ask for exceptions later if we don’t make the two-week window.”

It’s OK to write exceptions for a delay in listing a patient because you had to wait for kidney or liver functions to recover, she adds. Functions don’t need to be normal, but they should be robust enough to endure transplant surgery and give patients the best chance at a good outcome.