Return of spontaneous circulation (ROSC) is the resumption of a sustained

heart rhythm The cardiac conduction system (CCS) (also called the electrical conduction system of the heart) transmits the signals generated by the sinoatrial node – the heart's pacemaker, to cause the heart muscle to contract, and pump blood through the ...

that perfuses the body after

cardiac arrest Cardiac arrest is when the heart suddenly and unexpectedly stops beating. It is a medical emergency that, without immediate medical intervention, will result in sudden cardiac death within minutes. Cardiopulmonary resuscitation (CPR) and possib ...

. It is commonly associated with significant respiratory effort. Signs of return of spontaneous circulation include breathing, coughing, or movement and a palpable pulse or a measurable blood pressure. Someone is considered to have sustained return of spontaneous circulation when circulation persists and

cardiopulmonary resuscitation Cardiopulmonary resuscitation (CPR) is an emergency procedure consisting of chest compressions often combined with artificial ventilation in an effort to manually preserve intact brain function until further measures are taken to restore spont ...

has ceased for at least 20 consecutive minutes.

Predictors of ROSC

There are multiple factors during cardiopulmonary resuscitation (CPR) and

defibrillation Defibrillation is a treatment for life-threatening cardiac arrhythmias, specifically ventricular fibrillation (V-Fib) and non-perfusing ventricular tachycardia (V-Tach). A defibrillator delivers a dose of electric current (often called a ''cou ...

that are associated with success of achieving return of spontaneous circulation. One of the factors in CPR is the chest compression fraction, which is a measure of how much time during cardiac arrest are chest compressions performed. A study measured the effects of chest compression fraction on return of spontaneous circulation in out-of-hospital cardiac arrest patients with a non-ventricular fibrillation arrhythmia and it showed a trend to achieving return of spontaneous circulation with an increased chest compression fraction. Another study highlighted the benefits of minimizing chest compression intervals before and after shocking a patient's rhythm, which would in turn increase chest compression fraction. A

coronary perfusion pressure Coronary perfusion pressure (CPP) refers to the pressure gradient that drives coronary blood pressure. The heart's function is to perfuse blood to the body, however the heart's myocardium must, itself, be supplied for its own muscle function. The ...

of 15 mmHg is thought to be the minimum necessary to achieve ROSC. Pertaining to defibrillation, the presence of a shockable rhythm (

ventricular fibrillation Ventricular fibrillation (V-fib or VF) is an abnormal heart rhythm in which the ventricles of the heart quiver. It is due to disorganized electrical activity. Ventricular fibrillation results in cardiac arrest with loss of consciousness and no p ...

or pulseless

ventricular tachycardia Ventricular tachycardia (V-tach or VT) is a fast heart rate arising from the lower chambers of the heart. Although a few seconds of VT may not result in permanent problems, longer periods are dangerous; and multiple episodes over a short period ...

) is associated with increased chances of return of spontaneous circulation. Although a shockable rhythm increases chances for return of spontaneous circulation, a cardiac arrest can present with

pulseless electrical activity Pulseless electrical activity (PEA) refers to cardiac arrest in which the electrocardiogram shows a heart rhythm that should produce a pulse, but does not. Pulseless electrical activity is found initially in about 55% of people in cardiac arrest. ...

asystole Asystole (New Latin, from Greek privative a "not, without" + ''systolē'' "contraction") is the absence of ventricular contractions in the context of a lethal heart arrhythmia (in contrast to an induced asystole on a cooled patient on a heart-lun ...

, which are non-shockable cardiac rhythms.

Prognosis

Return of spontaneous circulation can be achieved through cardiopulmonary resuscitation and defibrillation. Though ROSC is necessary for survival, it is not, itself, a predictor of a favorable medium- or long-term outcome. Patients have died not long after their circulation has returned. One study showed that those who had had an out-of-hospital cardiac arrest and had achieved return of spontaneous circulation, 38% of those people had a cardiac re-arrest before arriving at the hospital with an average time of 3 minutes to re-arrest. Patients with sustained ROSC generally present with

post-cardiac arrest syndrome Post-cardiac arrest syndrome (PCAS) is an inflammatory state of pathophysiology that can occur after a patient is resuscitated from a cardiac arrest. While in a state of cardiac arrest, the body experiences a unique state of global ischemia. Thi ...

(PCAS). Longer time-to-ROSC is associated with a worse presentation of PCAS.

Lazarus phenomenon Lazarus syndrome (the Lazarus heart), also known as autoresuscitation after failed cardiopulmonary resuscitation, is the spontaneous return of a normal cardiac rhythm after failed attempts at resuscitation. It is also the spontaneous return o ...

is the spontaneous return of circulation after cardiopulmonary

resuscitation Resuscitation is the process of correcting physiological disorders (such as lack of breathing or heartbeat) in an acutely ill patient. It is an important part of intensive care medicine, anesthesiology, trauma surgery and emergency medicine. W ...

attempts have stopped in someone with cardiac arrest. This phenomenon most frequently occurs within 10 minutes of cessation of resuscitation, thus passive monitoring is recommended for 10 minutes.

References

Cardiology {{Circulatory-stub