Cardiac arrestCirculatory arrest

resuscitation, cardiopulmonary resuscitation, cardiopulmonary resuscitation

Definition

A cardiac arrest correctly describes a cardiovascular arrest in which the heart stops pumping blood into the circulation. In a cardiac arrest, the affected person becomes dizzy after a few seconds and loses consciousness after half a minute. Respiration stops after two minutes, and another two minutes later the first brain damage occurs.

In principle, cardiac arrest can occur due to many heart diseases. These include heart attack, cardiac arrhythmia, cardiac insufficiency, etc. An electrical accident can also be the trigger for a cardiac arrest.

For particularly complex operations, a cardiac arrest can also be triggered by medication for a planned period of time. In cardiac arrest or circulatory arrest (the terms are often used synonymously), a distinction is made as to whether or not there is still electrical activity in the heart. Normally, the heartbeat is triggered by a steady electrical excitation of the heart muscle cells.

In the so-called hyperdynaemic form of circulatory arrest / cardiac arrest, “circulating” electrical excitation occurs, i.e. the heart muscle cells are all excited, but not synchronously. You can imagine this like an orchestra. This is normally coordinated by the conductor in such a way that harmonious sounds are created.

In the heart, the sinus node is the conductor; it sets the beat. During the circular excitations, all instruments would play, but they would not pay attention to the conductor and no harmonic sounds would be produced, which here stands for the normal heartbeat. In the case of hyperdynaemic circulatory arrest, the heart twitches, but there is no beat that actually pumps blood.

Examples of hyperdynaemic circulatory arrest are ventricular fibrillation and pulseless ventricular tachycardia. In the latter case, the heart beats in a reasonably orderly fashion, but so fast that it cannot build up any pumping power. The other form of cardiac arrest is hypodynamic arrest.

In this case, the orchestra is completely silent. Nobody plays. In the heart, the sinus node does nothing and no heart muscle cell is excited.

These two forms of cardiac arrest are therefore treated slightly differently. To stabilize the patient permanently, the cause of the cardiac arrest must be found. This could be, for example, a pericardial tamponade.

In this case, blood runs through a tear into the pericardium. Since the pericardium cannot expand, after a short time there is so much blood in the bag that it creates enough pressure to prevent the heart from beating. Another reason for a cardiac arrest can be poisoning of all kinds.

For example, by drugs or medication. A heart attack or pulmonary embolism can also be the cause of cardiac arrest. A tension pneumothorax can also be the cause.

The tension pneumothorax is a severe form of pneumothorax. In this case, air is trapped between the lung and the pleura due to an injury to the ribcage. This causes the lung to collapse because it is normally held by negative pressure on the inner thoracic wall.

If shock occurs as a result of a serious accident with great blood loss, this may be one cause. Also drowning, electrical accidents (these especially trigger ventricular fibrillation), severe hypothermia and heart failure can trigger cardiac arrest. All these illnesses are treated in the clinic once the circulation is restored.