A cardiopulmonary arrest (CPA) occurs when the heart is no longer able to pump blood around the body and/or the lungs to exchange oxygen and waste gas effectively. When this occurs, it can lead to irreversible damage and death.

Cardiopulmonary arrest (CPA) can occur for various reasons, ranging from underlying disease to electrolyte (salt) imbalances, or medication reactions. Sometimes a cardiopulmonary arrest will occur due to a combination of reasons. Some causes of CPA are reversible while others, sadly, are not.

Cardiopulmonary resuscitation (CPR) is the procedure which aims to save a patient’s life in the event of an arrest.

The first step is Basic Life Support (BLS), which involves performing chest compressions to push blood around the body and providing ventilation (breathing for the patient).

After chest compressions and ventilation have been established, Advanced Life Support (ALS) involves multiparameter monitoring of the patient to better assess what is happening. Medications, such as adrenaline, may be administered.

Once an arrest is identified, the presence or absence of breathing will be checked, and the airways will be checked for obstructions. If there is any doubt about breathing or circulation, CPR will be commenced. CPR is always undertaken by a team of trained staff.

Chest compressions will be commenced first. An airway will then be secured, using a tube placed into the airway, and we will then start breathing for the patient.

In our hospital, the patient will then be attached to a variety of monitoring equipment. This can include an ECG which monitors electrical activity in the heart, and a capnograph which monitors the amount of carbon dioxide being expelled by the body. Medications that have previously been given will be reversed if possible, and drugs such as adrenaline and atropine will be given to encourage the heart to beat. During CPR we may take blood to assess for reversible causes of cardiac arrest.

If an arrest happens and CPR is commenced, you will be contacted as early in the process as possible. We will inform you what has happened, what work is being carried out, and what our next steps are. The prognosis and any recommendations we have will also be discussed.

You will be asked if you want us to continue CPR - there are no right and wrong answers to this question and we will do our best to help you with the decision. In the next paragraph we will discuss the survival rates associated with CPR.

CPR, especially in animals, is not as simple as medical TV shows make it seem.

In an otherwise healthy animal that is having an elective procedure, who arrests due to an anaesthetic-related event, there is a 50% likelihood of survival.

Sadly, only 6-7% of other animals who experience a cardiopulmonary arrest will survive to discharge. Many patients who initially recover will either have a further arrest or experience a worsening in their condition.

Following CPR, your pet will need intensive monitoring and treatment. This will be focused on trying to prevent further arrests and other problems that can occur after cardiopulmonary arrest, such as seizures and pain.

Following CPR, some animals will need to spend time on a ventilator, a machine which will breathe for them, until hopefully they regain the ability to breathe on their own.

This is a decision for you to make after consultation with your vet.  The decision might depend in part on your pet’s situation and health status. It can be worth revisiting this decision at various points during treatment.

This may be raised by you or us at any point during a patient’s care, especially if the clinical situation changes.