How long should doctors wait for a “flatline” to appear before declaring a person dead? How can you be sure that your heartbeat and circulation will not return?
The Most often, people die when their heart stops beating. However, there is limited evidence of this How long does one have to wait to determine death when the heart stops?. This lack of information has implications for clinical practice and organ donation.
A basic principle of organ donation is the dead donor rule: Donors must be dead prior to organ removal, and the organ removal must not be the cause of death. The lack of evidence of how long to wait before declaring death creates tension: if doctors wait too long after the heart has stopped, the quality of organs deteriorates.
However, if you don’t wait long enough, there is a risk that organ recovery will resume before death actually occurs.
Our interdisciplinary team For the past decade, doctors, bioengineers, and veteran clinical researchers have studied what happens when a person dies after their heart has stopped. We have focused on ICU patients who have died after deprivation of life support, as these patients may also be eligible for organ donation.
In particular, we were interested Understand whether the heart is able to restart on its ownwithout procedures such as cardiopulmonary resuscitation (CPR) or medication.
A closer look at the flatline at the end of life
Our current study, published in the New England Journal of Medicinepresents observations on the dying process of 631 patients in Canada, the Czech Republic and the Netherlands who died in an intensive care unit. All patient family members consented to participate in the research.
In addition to collecting medical information about each patient We created a computer program Capture and review heart rate, blood pressure, blood oxygen levels, and breathing patterns directly from bedside monitors. As a result, we were able to analyze end-of-life flatline patterns for 480 out of 631 patients – including whether and when circulatory or cardiac activity returned after at least a minute of interruption.
As it turns out, the classic line of death isn’t that simple. We found that the activity of the human heart often stops and restarts several times during a normal process of death.
We found a stop-and-start pattern in 67 (14 percent) of 480 “flatline” signals checked. The longest time the heart stopped by itself before restarting was four minutes and 20 seconds. The longest time cardiac activity continued after restarting was 27 minutes, but most restarts only took a second or two. None of the patients we observed survived or regained consciousness.
We also found that it was common for the heart to continue exhibiting electrical activity long after the blood flow or pulse was stopped. The human heart works as a result of electrical stimulation of the nerves, which causes the heart muscle to contract and help increase blood flow – the pulse you can feel in your arteries and veins.
We found that the heart rate (electrical stimulation that causes the heart muscle to move) and pulse (movement of the blood in the veins) stopped together in only 19 percent of patients. In some cases, the electrical activity of the heart continued for over 30 minutes without any blood flow.
Why is it important to understand death?
The results of our study are important for several reasons.
First, the observation of cardiac activity and circulation being stopped and restarted, often part of the natural process of dying, is comforting for doctors, nurses, and bedside family members. Intermittent signals on night monitors can sometimes be alarming when observers interpret them as signs that life is unexpectedly returning. Our study provides evidence that stops and starts are to be expected during a normal process of dying without CPR and that they do not result in regaining consciousness or survival.
Second, our finding that the longest pause before restarting cardiac activity by itself was four minutes and 20 seconds supports the current practice of Wait five minutes after the circulation has stopped before declaring death and proceeding with organ repair. This helps ensure organ donation organizations that death determination practices are safe and appropriate.
Our results are used to better inform guidelines and guidelines for the international practice of organ donation. In order for donation systems to work and someone pronounced dead, it must be trusted that the statement is truly true. Trust makes it possible for families Choose to donate during a time of grief and enables the medical community to ensure safe and consistent end-of-life care.
This study is also important in enhancing our broader understanding of the natural history of death. We have shown that figuring out when dead is really dead may not be that easy. It requires careful observation and close physiological monitoring of the patient. Additionally, it requires an understanding that, as in life, there are many patterns that the dying process can adopt.
Our work is a step in realizing the complexities of dying and suggests that we need to go beyond the idea of a simple flatline to indicate when death has occurred.
This article was co-authored by Laura Hornby, research manager and consultant at the Children’s Hospital of the Eastern Ontario Research Institute and Canadian Blood Services, and Nathan Scales, biomedical engineer and research fellow at the Dynamical Analysis Lab, Ottawa Hospital Research Institute.