This entry relates to situations in hospitals in England and Wales. The laws and guidelines may be different elsewhere. This entry is no substitute for a full discussion with the qualified medical practitioner who is responsible for the care of the patient.
This works by generating small, rhythmical electric currents that follow defined pathways around the heart muscle, making it contract in a co-ordinated way. In order to work, the heart needs to be supplied with blood containing the right levels of oxygen, potassium and other substances. If the heart fails to pump the blood around the body such that all signs of life (including breathing and pulse) disappear, this is termed cardiac arrest.
The brain is the essential organ most dependent on an oxygen-rich blood supply to stay alive. Unless partially protected by low temperatures (below 33°C), the nerve cells that make up the brain start to die just a minute or two after cardiac arrest.
Cardiopulmonary Resuscitation (CPR)
CPR is mouth-to-mouth breathing together with chest compressions. The aim of this is to artificially supply the brain and other vital organs with enough oxygenated blood to enable them to survive a little longer, giving time for the underlying cause of the cardiac arrest to be corrected. CPR should only be performed on a person who has had a cardiac arrest. It is the last and most desperate defence medicine has against death, but it has saved many lives by buying time until the heart can be restarted.
Restarting the Heart
If the cardiac arrest occurs in hospital, CPR is commenced and then a cardiac arrest team is called to attempt to restart the patient's heart.
If the electric currents that make the heart beat do not follow their proper pathways, the heart will not beat in the most efficient way. This is especially likely if the heart muscle itself is unstable, for example during or just after a myocardial infarction (heart attack). The extreme case is the chaotic, completely unco-ordinated rhythm called ventricular fibrillation, which does not produce a heart 'beat' at all and is sometimes correctable by giving the heart an electric shock: this is called defibrillation. Some airports and shopping centres have staff trained to use automatic defibrillators which can read the heart's electrical activity and deliver shocks if appropriate.
Sometimes the cause of the cardiac arrest isn't the electricity in the heart, but some other problem in the body that makes it impossible for the heart to work at all. Some causes are potentially quickly reversible - such as airway obstruction or very high potassium levels - but some causes cannot be quickly reversed, as in the presence of overwhelming infection or aggressive cancer.
What if the Heart is Successfully Restarted?
Even with the best CPR possible, the brain, heart and other organs will not have had their normal oxygen-rich blood supply during the period of cardiac arrest. So, after the heart is restarted, the organs are injured, which makes them unstable. In the short-term (hours and days) this puts the patient at risk of further cardiac arrest, and the patient will need close observation and continuous monitoring of the heart's electrical activity. In the longer term there may be temporary or permanent damage to any of the body's organs, which may require support from machines and/or drugs on an intensive care or coronary care unit. There may also be physical damage to the body, such as rib fractures from CPR or skin burns from the electric shocks.
The best possible outcome would be that the patient (especially if young and previously healthy) makes a full recovery and goes back to normal life. The worst possible outcome might be that the patient (especially if the cardiac arrest was long or the patient had some pre-existing disease) ends up permanently and severely brain-damaged.
What if the Team is Unable to Restart the Heart?
By definition, if the heart cannot be restarted, the patient is dead. Attempts at restarting the heart, interspersed with periods of CPR, can take anything from minutes to hours in some cases. Clearly this is not the most peaceful or dignified way for a person to die.
How Likely is it That the Heart Can be Restarted?
This depends very much on how healthy the patient's organ systems are, any illness currently affecting the patient and the cause for the cardiac arrest. The first two factors are something only the senior doctor responsible for the patient's care can fully assess. Because of this, the default position in hospitals is that if there is any doubt, trained staff are legally obliged to start CPR in the event of cardiac arrest, just in case it might work.
When Should CPR not be Started?
Above all, CPR, like any other medical treatment, must not be given to a patient who has clearly (and with full understanding) said that they do not want it. This needs to be documented properly because it is a sort of 'advance directive'. Similarly, if the doctor discusses CPR with a mentally 'competent' patient, the patient may refuse this treatment. However, the difficulty is in being sure that a patient, who may be very ill or experiencing a lot of psychological stress, really understands the issue fully enough to be legally 'competent' to refuse treatment. If the patient has a cardiac arrest and there is any doubt over the validity of such a directive (for example, if circumstances are different from those that may have been foreseen at the time of the directive) then the team will proceed to treat in the patient's best interests, which may include CPR.
As described above, even if the heart is successfully restarted there may be grave consequences for the patient. The Resuscitation Council (UK) states that 'ideally resuscitation should be attempted only in patients who have a very high chance of successful revival for a comfortable and contented existence'.
In English law, CPR, like any other medical treatment, should not be given to a patient if the doctor in charge of the patient's care is reasonably certain that it would not be of any benefit to that patient. If a patient has either recent or long-standing problems with one or more organ systems, or is generally very frail, the doctor may decide that if the patient were to deteriorate and suffer a cardiac arrest, then even in the event that the heart could be restarted, the outcome would be a length or quality of life that would be unacceptable to the patient. He would therefore document a DNR (Do Not Resuscitate) or DNAR order (DNAR is an acronym which stands for Do Not Attempt Resuscitation in the event of cardiac arrest). If the patient's condition changed significantly during the hospital stay, this decision would be reviewed.
Why Talk to the Relatives About This?
In English law the responsibility for making the DNAR decision is the doctor's alone. However, it is important for the doctor to make sure he has all the information he needs, including the patient's usual state of health and an idea of the minimum length and quality of life the patient would consider acceptable. This is one reason the doctor will often need to talk to the relatives before making the decision. The relatives must not make any medical decision on the patient's behalf: also, the consequences for them of doing this could be lasting trauma if the patient then went on to suffer adverse effects from the relative's decision, or even adverse speculation if the relative was a beneficiary in the patient's will.
In some cases the doctor will also discuss CPR with the patient, but in other cases it may be felt to be unfair or even damaging to put an already vulnerable patient through such a distressing discussion.
Another reason for talking to the patient and the relatives is to explain that a DNAR decision applies only to CPR and the calling of the cardiac arrest team; the decision does not in itself affect any other aspect of the patient's care and treatment. It can be useful to clarify plans for other treatments as well, but they do not automatically follow from the DNAR order. Whatever is decided, the patient will still be entitled to full nursing care to alleviate any discomfort or distress.
Some Problems With the 'Not for CPR' Conversation
It is usually unpleasant to talk about the possible death of a person who is still alive. For the doctor, it is a reminder that despite the best treatment he or she can give, the person may nevertheless die. For the patient and family it may be a shock to hear that the doctors think that there is a possilibity of death. It is very human to feel angry or upset at this time. Relatives may feel the need to protect their loved one by insisting that they 'want everything done'. In reality, doctors will always tend to do everything they think might possibly work, and can find it difficult to admit that in some situations a treatment may be futile - meaning that the chances of benefit of that treatment to that patient would be so tiny as to approach zero. Eventually death will come to us all, but being able to deny this is part of human nature.
The information on this page is deliberately generalised to provide some background information for the lay person. Again, please talk to your doctor about these issues before reaching any conclusions.