Cardiac Arrest: Therapy

Reanimation (resuscitation)

First aid for cardiac arrest, ie, attempt of resuscitation by first responders before the arrival of emergency physicians has a major impact on the chance of survival. According to one study, patients with attempted resuscitation by first responders were still alive after 30 days in 10.5% of cases, whereas patients without attempted resuscitation by first responders were alive in only 4% of cases. Note: A stable lateral position can make it more difficult to recognize a respiratory arrest quickly and to start cardiac massage. Conclusion: The stable lateral position hinders the assessment of respiratory activity. General

  • Cardiopulmonary resuscitation (English : cardiopulmonary resuscitation, CPR) is required in cardiac and/or respiratory arrest.
  • Resuscitation of the heart is performed by cardiac massage, defibrillation (shock generator; treatment method against life-threatening cardiac arrhythmias) and administration of medication
  • Therapy for respiratory arrest involves clearing the airway and artificial respiration to restore gas exchange in the lungs
  • Basic life support can be distinguished from advanced life support (by professional helpers).
  • After prehospital circulatory arrest, the chances of survival are higher if patients are admitted to special centers (Cardiac Arrest Center). This also applies in individual cases of under-running resuscitation.
  • Review of permanent medication due topossible effect on cardiac arrest.

Indications

The European Resuscitation Council (ERC) lists the following situations in which professional rescuers should consider not resuscitating children and adults:

  • Safety of first responders is not assured.
  • An obviously fatal injury is present or irreversible death has occurred (safe signs of death).
  • When asystole without reversible cause persists for more than 20 minutes despite ongoing advanced resuscitative measures.
  • There is a valid and applicable living will.

Procedure during resuscitation

  • Check consciousness, call for help, attach AED (automated external defibrillator) if necessary.
  • A – Clear the airway
  • B – Ventilation
  • C – Circulation (cardiac massage)
  • D – Drugs (medication)

Check Awareness (Basic Life Support)

  • Address person, shake
  • If no response: call for help, back positioning

Clear airway (basic life support).

  • Hyperextension of the neck
  • Lifting the chin
  • Professional rescuers use suction devices, airway devices such as Güdel tube (to keep the upper airway open)

External chest compressions (basic life support).

  • Patient is lying on a hard surface in the supine position.
  • The pressure point is in the middle of the chest.
  • The pressure must be placed with the heels of the hands.
  • The chest should be pressed between 5 and 6 centimeters.
  • The pressure frequency should be between 100-120/ minute.
  • The chest must be completely unloaded after compression, i.e., do not continue to support the sternum during the unloading phase (“leaning”), as this may affect the speed of decompression, i.e., unloading, in addition to completeness; however, the hand is not lifted. It should be noted that: Compression: relief = 1: 1. For the success of cardiopulmonary resuscitation, the speed at which decompression is achieved (cardiac compression release velocity, CCRV) seems to be an important factor.
  • The rescuer kneels at the side of the patient; the upper body is vertical over the pressure point; the elbows are pushed through.
  • The helper should change after about 2 minutes.
  • Basically, lay resuscitation is started with 30 compressions, followed by 2 ventilations.
  • The compressions have a higher value in cardiopulmonary resuscitation than ventilation; in the first minutes after a cardiac arrest, the oxygen content in the blood is still sufficient.
  • Resuscitation duration:
    • At least 20 minutes; some guidelines do not give specific recommendations.
    • Performing a structured assessment after three cycles of cardiopulmonary resuscitation and rhythm analysis.

In a study of more than 11,00 patients (from the ROC and PRIMED studies), the median duration of resuscitation was 20 minutes, 13.5 minutes in patients whose circulation spontaneously returned, 23.4 minutes in those where it did not. Dangers of chest compressions

  • Rib/rib series fractures – especially in incorrect pressure point or elderly patients → do not interrupt/abort resuscitation.

Ventilation (basic life support)

  • Without aids: mouth-to-mouth/mouth-to-nose ventilation.
  • With assistive devices: professional rescuers use endotracheal tubes (breathing tube, a hollow plastic probe), laryngeal masks (laryngeal mask, means of keeping the airway open), etc. to secure the airway.
  • Two ventilations should not exceed 5 seconds.

Dangers of ventilation

  • Hyperventilation (deepened and/or accelerated breathing, i.e., lung ventilation increased above demand) can decrease the ejection fraction of the heart.
  • Hyperventilation increases the risk of regurgitation (backflow of gastric contents into the pharynx).
  • The risk of infection during respiratory donation is extremely low.

Advanced resuscitation (advanced life support).

  • Defibrillation (treatment method/shock generator against the life-threatening cardiac arrhythmias) in ventricular fibrillation and pulseless ventricular tachycardia/ventricular tachycardiaNote: In the case of pulseless electrical activity (PEA) or. Electro-mechanical dissociation (EMD), defibrillation remains ineffective.After successful defibrillation of ventricular fibrillation outside a hospital, ventricular fibrillation recurs in almost 2/3 of patients within 1 minute – in most cases even within 30 seconds.
  • Intubation – insertion of an endotracheal tube to secure the airway; supraglottic airway devices (SGA) are considered alternatives.
  • Application of drugs (e.g., epinephrine).
  • If necessary, extracorporeal cardiopulmonary resuscitation (eCPR), i.e., use of a heart–lung machine during ongoing cardiopulmonary resuscitation: emergency cannulation of a vein and artery and the start of extracorporeal circulation and membrane oxygenation (a machine partially or completely takes over the patient’s respiratory function).Indication: selected indications within a time window of 60 min after the start of resuscitation. Here, the decision to eCPR should be made within 20 min and based on defined parameters.

After successful resuscitation

  • Temperature management: unconscious patients after circulatory arrest should be cooled to 33 or 36 °C for at least 24 hours, regardless of the initial cardiac rhythm. Fever must be avoided as well as hyperoxia (excess oxygen) of any case for 72 hours.

Resuscitation in children

  • In children with cardiovascular/temporal arrest, initial resuscitation is five breaths; thereafter, resuscitation continues with 15 chest compressions (chest compressions) alternating with two breaths; laypersons may alternatively resuscitate with a 30:2 ratio, as should be familiar from adult resuscitation.

Outcome (treatment success)

  • Outcome of 102,000 out-of-hospital cardiac arrest patients:
    • 31% sustained return of spontaneous circulation (at least 20-minute pulse); return of spontaneous circulation was largely constant at about 30% in the 45- to 80-year-old groups
    • 9.6% were able to leave the hospital alive; subgroup analysis: after resuscitation were able to leave the hospital:
      • 16.7% of those under 20 years of age.
      • 1.7% of resuscitated very old people
    • 7.9% did not sustain serious neurologic damage (defined as a score of one or two points according to the Cerebral Performance Category, CPC)
    • 88% of successfully resuscitated patients under 20 years of age had no serious neurologic damage
    • 70% of resuscitated very old patients had no serious neurological damage
  • Patients resuscitated by lay resuscitation using an automated external defibrillator (AED) had an absolute risk of death or need for long-term care of only 2.0% (0.0-4.2).The risk was even lower than in cases in which medical first responders, who usually arrive later, performed resuscitation (3.7%; 2.5-4.9).
  • Patients who were intubated (“insertion of a hollow tube into the trachea”) within 15 minutes in the in-hospital setting because of cardiac arrest had a higher mortality (death rate) than the control patients who were not intubated (16.4% vs. 19.4%); this was also true for a good functional outcome (= at most moderate neurologic deficit) (10.6% vs. 13.6%). The group of patients who initially had a shockable rhythm showed better survival without intubation (39.2% vs 26.8%).

Further notes

  • Individuals who have suffered a cardiac arrest and had been taking statins have a better chance of surviving the event than individuals without prior statin therapy:
    • 19% higher chance of being hospitalized alive after cardiac arrest.
    • 47% higher chance of being discharged alive from the hospital
    • 50% higher chance of still being alive one year after the event
  • According to one study, intubation and use of supraglottic assist devices in adults with cardiac arrest provides no benefit in patients with shockable rhythm and only a small benefit in patients with nonshockable rhythm.CONCLUSION: In patients with shockable rhythm, rescuers should focus primarily on defibrillation and continuous chest compressions rather than ventilation.
  • Registry data from Sweden show that in prehospital cardiac arrest, chest compression (chest compressions) alone saves lives.
    • Only chest compression (CO-CPR, compression-only cardiopulmonary resuscitation), 14.3 percent of patients with cardiac arrest survived the first 30 days (in 2000, it had been only eight percent; in 2000, the CPR guidelines (English : cardiopulmonary resuscitation) were changed in Sweden: even trained first responders are allowed to refrain from mouth-to-mouth resuscitation if they feel disgust)
    • Classical resuscitation with ventilation (S-CPR): 16.2 percent of patients were saved
    • Note: CO-CPR was inferior to classical resuscitation with ventilation when rescuers arrived later than 10 minutes after cardiac arrest. This is not surprising, since the remaining oxygen in the blood and lungs is depleted after 10 minutes.
  • Moderate hypothermia (cooling the body surface to 33°C for 24 hours) resulted in a favorable effect on the neurologic outcome of comatose patients after circulatory arrest and successful resuscitation if they had initially had a nonshockable rhythm: after 90 days, 10.2% of patients in the hypothermia group were still alive and had a cerebral performance category (CPC) score of 1 or 2; scores of 1 and 2 are considered a favorable outcome.

Potential complications

  • Rib fractures (rib fractures: manual resuscitation versus mechanical resuscitation: 77% versus 96%).
  • Sternal fractures (sternal fractures: manual resuscitation versus mechanical resuscitation: 38% versus 80%)
  • Soft tissue injuries (manual resuscitation versus mechanical resuscitation: 1.9% versus 10%; these included soft tissue injuries that were potentially life-threatening)

Therapy of patients who survived a sudden cardiac death event

  • Therapy of choice for patients who have survived a sudden cardiac death event is the implantable cardiac defibrillator (ICD)
  • In patients with persistent ventricular arrhythmias (arrhythmias originating in the ventricle), catheter ablation is a very promising therapeutic modality.