These protocols are often initiated by a code blue, which usually denotes impending or acute onset of cardiac arrest or respiratory failure, although in practice, code blue is often called in less life-threatening situations that require immediate attention from a physician. Other
Resuscitation with extracorporeal membrane oxygenation devices has been attempted with better results for in-hospital cardiac arrest (29% survival) than out-of-hospital cardiac arrest (4% survival) in populations selected to benefit most. Cardiac catheterization in those who have survived an out-of-hospital cardiac arrest appears to improve outcomes although high quality evidence is lacking. It is recommended that it is done as soon as possible in those who have had a cardiac arrest with ST elevation due to underlying heart problems.The precordial thump may be considered in those with witnessed, monitored, unstable ventricular tachycardia (including pulseless VT) if a defibrillator is not immediately ready for use, but it should not delay CPR and shock delivery or be used in those with unwitnessed out of hospital arrest. Prognosis
The overall chance of survival among those who have cardiac arrest outside hospital is poor, at 10%. Among those who have an out-of-hospital cardiac arrest, 70% occur at home and their survival rate is 6%. For those who have an in-hospital cardiac arrest, the survival rate one year from at least the occurrence of cardiac arrest is estimated to be 13%. One year survival is estimated to be higher in people with cardiac admission diagnoses (39%), when compared to those with non-cardiac admission diagnoses (11%).
Guidelines following the 2000 International Liaison Committee on Resuscitation (ILCOR) recommendations were for rescuers to look for "signs of circulation", but not specifically the pulse. These signs included coughing, gasping, colour, twitching, and movement. However, in face of evidence that these guidelines were ineffective, the current recommendation of ILCOR is that cardiac arrest should be diagnosed in all casualties who are unconscious and not breathing normally, a similar protocol that of which the European Resuscitation Council has adopted. In a non-acute setting where the patient is expired, diagnosis of cardiac arrest can be done via molecular autopsy or postmortem molecular testing which uses a set of molecular techniques to find the ion channels that are cardiac defective. This could help elucidate the cause of death in the patient. Other physical signs or symptoms can help determine the potential cause of the cardiac arrest. Below is a chart of the clinical findings and signs/symptoms a person may have and a potential cause associated with it. Classifications
Clinicians classify cardiac arrest into "shockable" versus "non-shockable", as determined by the EKG rhythm. This refers to whether a particular class of cardiac dysrhythmia is treatable using defibrillation. The two "shockable" rhythms are ventricular fibrillation and pulseless ventricular tachycardia, while the two "non-shockable" rhythms are asystole and pulseless electrical activity. Prevention
With the lack of positive outcomes following cardiac arrest, efforts have been spent finding effective strategies to prevent cardiac arrest.