Lazarus syndrome refers to your blood circulation returning spontaneously after your heart stops beating, and fails to restart despite cardiopulmonary resuscitation (CPR).

In short, it’s returning to life after it appears that you’ve died.

Lazarus is a character in the Bible who emerged from his tomb alive and well 4 days after his death.

The syndrome was named after him because when your circulation spontaneously restarts, it looks like you’ve come back from the dead.

It’s also known by several other names, such as:

  • Lazarus phenomenon
  • Lazarus heart
  • autoresuscitation
  • autoresuscitation after failed CPR
  • delayed return of spontaneous circulation after failed CPR

In this article you’ll discover that, although it looks like you’ve returned from the dead, in Lazarus syndrome you never really die at all.

Your heart is a pump that pushes blood through your blood vessels to all your organs and tissues in your body. When it stops beating, circulation stops, and your organs begin to fail because they’re no longer getting oxygen.

Usually, the reason your heart stops can’t be corrected or reversed, and death soon follows despite CPR. Sometimes, CPR is successful and restarts your heart, especially if the cause is a reversible problem.

Very rarely, a problem develops during CPR that prevents your heart from restarting. Lazarus syndrome happens when that problem resolves itself shortly after CPR stops, and your heart starts beating again.

Lazarus syndrome is very rare. One 2015 case report found that only 32 cases were reported between 1982 and 2008.

According to the Bible, Lazarus was dead for 4 days before Jesus brought him back to life. In Lazarus syndrome, “death” doesn’t last nearly as long.

According to a 2020 research review, In most documented cases of Lazarus syndrome, circulation typically returned within 10 minutes of stopping CPR.

Many people think that death occurs as soon as the heart stops beating and breathing ceases.

But in fact, death is a process in which all your organs necessary for life progressively fail. You aren’t actually considered dead until the function of all your organs, including your brain, irreversibly stop.

Declaring someone dead immediately after CPR stops leaves the door open for Lazarus syndrome to occur. Doctors can avoid this by:

  • waiting at least 10 minutes after CPR stops before declaring someone dead
  • keeping a heart monitor attached to the person to confirm loss of a heart rhythm for 10 minutes or more
  • disconnecting the device used for ventilation for 10 seconds to relieve air trapping when it’s suspected

Most importantly, medical personnel need to confirm the loss of function of multiple organs before declaring death. This includes:

  • lack of audible heart sounds
  • absence of a palpable pulse
  • fixed and dilated pupils that don’t respond to light
  • lack of response to pain

It’s not known why Lazarus syndrome happens, but there are several theories that may explain it. Let’s look at some possibilities.

Air trapping

Air trapping is the most common explanation for Lazarus syndrome. It’s more likely to happen if you have chronic obstructive lung disease (COPD).

When air is pushed into your lungs too rapidly during CPR (hyperventilation), there’s no time to exhale it, so it builds up. This is called air trapping.

As the air builds up, the pressure inside your chest increases. Eventually, it gets so high that your blood has trouble moving through your chest veins to your heart, and your heart has trouble pumping blood out to your body. This can:

  • stop your circulation
  • cause cardiac arrest
  • prevent your heart from restarting during CPR

When CPR stops, the trapped air starts leaving your lungs, which reduces the pressure in your chest.

Eventually, blood from your body can flow to your heart and be pumped to the rest of your body. Circulation can return, and it can look like your heart has restarted itself.

Delayed medication delivery and action

Medications given during CPR need to reach your heart to work. When air trapping stops blood from returning to your heart, anything in your blood, including medication given through intravenous (IV) in your arms or legs, can’t get there.

Once air trapping resolves and the pressure in your chest is low enough, blood will flow to your heart, carrying the medication with it. If the medications are effective, your circulation will spontaneously return.

Temporary cardiac arrest after defibrillation

During CPR, a defibrillator may be used to send an electrical shock to your heart to try to restart it or to reset an irregular heart rhythm known as arrhythmia.

Sometimes there’s a delay between the shock and its effect. If it’s long enough, it appears that your circulation returns spontaneously rather than because of the shock.

Other reversible causes

Some conditions such as a high level of potassium or too much acid in your blood can cause your heart to stop beating.

These conditions are usually treated during CPR, but they can take some time to resolve. If they don’t improve until CPR stops, it may look like your circulation returns spontaneously.

Only about 63 cases of Lazarus syndrome have been documented in medical journals. Some of these cases have made it into the news headlines, such as:

  • A 20-year-old woman in Detroit was declared dead after 30 minutes of CPR. She was taken to the funeral home where staff discovered she was breathing. She was treated in the hospital, but died 2 months later.
  • A 23-year-old British man was pronounced dead after failed CPR. About 30 minutes later, a priest gave him last rites and noticed he was breathing. He died in the hospital 2 days later.
  • In Ohio, a 37-year-old man collapsed at home. In the hospital, his heart stopped, and he was pronounced dead despite 45 minutes of CPR. Several minutes later, his family noticed his monitor showed a heart rhythm. A week later, he was well enough to go home.

Although it may seem like some people come back to life after dying, someone with Lazarus syndrome experiences their circulation returning spontaneously after their heart stops beating.

The syndrome is very rare and only happens after CPR is performed. Many doctors think air trapping due to hyperventilation during CPR is the most likely cause of this syndrome.

Doctors can avoid declaring someone’s death by observing the person for at least 10 minutes after CPR stops.