Cardiopulmonary resuscitation (CPR) is an emergency, hopefully life-saving, procedure, performed on someone who has suffered a cardiac arrest i.e. who has no spontaneous breathing (or is only gasping) and/or has no pulse, in an attempt to try to prevent damage to their brain while additional attempts are made to restore their breathing and their circulation. Both respiration and circulation are required to ensure that oxygen is delivered to the brain, which begins to suffer reversible damage after about 4 minutes of a lack of oxygen from a cardiac arrest and permanent damage after about 7 minutes.
In brief, basic CPR involves giving 30 chest compressions (to a depth of 5-6 cm and at a rate of 100-120 per minute) followed by 2 rescue breaths (for one second each), continuing in this manner in cycles until the collapsed individual either recovers or help arrives. Advanced CPR is more complex than basic CPR and involves the additional use of various techniques and drugs to maintain respiration and circulation while attempts are made to identify and treat both the underlying abnormal heart rhythm and cause of the cardiac arrest, possibly by way of “shocking” (defibrillating) the heart back into its normal rhythm.
Unfortunately, individuals who suffer a cardiac arrest out of hospital generally have a very poor chance of survival, with studies suggesting this may be as low as only a few percent. The outlook is not quite so bleak for patients who suffer an arrest in hospital, where there are usually trained professionals on hand, a dedicated cardiac arrest team skilled in advanced life support, and appropriate equipment and medication available to assist in the attempt to resuscitate, with studies suggesting that up to a third of patients who suffer a witnessed in-hospital arrest survive to discharge.
These figures on the face of it are not overly encouraging and it would be easy to think that, given the emergency nature of resuscitation, the fact that many patients are already very ill (which may be why they arrested in the first place), and the generally poor chances of survival following an arrest, even in hospital, it would be nigh on impossible to identify, let alone prove, that things might have gone unacceptably wrong and that an arrest, or brain damage/death resulting from an arrest, was actually avoidable.
Studies suggest that, of those patients who do survive an in-hospital cardiac arrest such that they are able ultimately to be discharged from hospital, up to two-thirds of them do not suffer from any major brain injury as a consequence of their arrest. Therefore, if someone survives an in-hospital arrest but is left profoundly brain damaged, it can be worth looking closely at why that was the case.
There are many factors that affect the prospects of survival, including:
- age (younger patients have a better prognosis);
- the nature and extent of underlying medical problems;
- the first documented heart rhythm (ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) have a better prognosis than asystole or pulseless electrical activity (PEA));
- the duration of the arrest (the shorter, the better);
- the location of the arrest in hospital (intensive, critical or coronary care unit arrests have a better outcome than ward arrests); and
- the time of day/day of the week (nighttimes and weekends tend to be worse).
Therefore, it may also be worth investigating the medical care surrounding an in-hospital arrest when someone has had a wholly unanticipated arrest or unexpectedly dies following an arrest.
From the clinical negligence perspective, it is important to look at the patient’s management in the lead up to the arrest (“pre-arrest”), the performance of the resuscitation (“peri-arrest”) and the clinical care immediately following the arrest (“post-arrest”).
Was the arrest avoidable? There are numerous causes of an arrest, but the commonest precipitating causes in an adult are an abnormal heart rhythm (arrhythmia), very low blood pressure (hypotension), acute breathing problems (acute respiratory insufficiency) and angina/heart attack (acute myocardial ischaemia/infarction). It may be the case that these (and/or other) problems were not identified by hospital staff, either at all or quickly enough, prior to the arrest, such that, if they had been, the arrest would have been avoided, thus avoiding the patient’s death or serious brain injury. It may also be that inappropriate treatment by the clinicians precipitated the arrest. For example, I have successfully settled a case in which a particular medication precipitated an arrest and, although the patient was successfully resuscitated, they were left severely brain damaged. It transpired that the medication had been wholly inappropriate and the arrest was completely avoidable.
Even if the arrest was inevitable and unavoidable, was it recognised, was CPR commenced sufficiently quickly enough by hospital staff and was the resuscitation carried out appropriately? I have succeeded in such resuscitation cases, including where the hospital staff inexplicably failed to recognise an arrest, unacceptably delayed commencing basic life support following a collapse, performed basic CPR in a substandard way and failed to call the cardiac arrest team in a timely manner, allowing critical minutes to pass without CPR and resulting in avoidable profound brain injury or death. I have also succeeded in other cases where inappropriate drugs were used or key drugs were not used during the resuscitation, against recognised protocols, as well as in one case where non-functioning arrest equipment resulted in a patient not surviving an arrest.
If a patient does survive an in-hospital arrest, statistically they have a greater than 50% chance of being discharged from hospital without major brain injury. It may be important, therefore, to ensure that the post-arrest care of someone who is successfully resuscitated, but who ultimately ends up profoundly brain injured, is closely examined. It may be that the management was perfectly acceptable. However, I have successfully concluded cases in which the immediate post-arrest ITU care was found to be unacceptably wanting, including the failure to recognise that an endotracheal tube had been incorrectly inserted, the failure to recognise that the tube had become dislodged and the failure to identify and treat a post-arrest pneumothorax (air in the pleural space) resulting in profound hypoxia and significant brain injury. It may not always be the case, therefore, that it was actually the arrest that was the cause of the eventual brain injury.
Cases involving brain injury consequential to a cardiac arrest are necessarily medically complicated and can be very difficult to prove; cases where death is the outcome even more so. However, there are certain situations in which it can be possible to establish that things did go unacceptably wrong and that the catastrophic outcome could have been avoided with proper care.