Cardiac Arrest

Introduction

Cardiac arrest is the sudden cessation of cardiac pump function.
If there is no spontaneous reversal or
resuscitatory measure, death results.
It is the commonest cause of cardiovascular deaths among Caucasians.
It peaks between ages 0 – 6 months and 45 – 75 years

Aetiology

  • Myocardial infarction
  • Arrhythmias
  • Drugs and other substances of abuse
  • Sudden infant death syndrome
  • Miscellaneous

Clinical features

  • Usually sudden collapse
  • Unrecordable blood pressure
  • Loss of peripheral pulses
  • Cessation of respiration
  • May be asymptomatic
  • Complaints may be nonbspecific
  • Presentation may be that of
    underlying cause

Differential diagnoses

  • Syncope
  • Seizures

Complications

  • Acute renal failure
  • Cerebrovascular accident

Investigations

After the initial rapid assessment and resuscitation:

  • Electrocardiography
  • Echocardiography
  • Urea, Electrolytes and Creatinine
  • Blood gases
  • Chest radiograph
  • Lipid profile

Treatment objectives

  • Prompt restoration of cardiac and respiratory function
  • Monitoring of impact of cardiac arrest on the various associated organs
  • Intervention to restore normal functions
  • Formulation of a broader and more
    comprehensive diagnostic and treatment plan
  • Eliminate/control aetiological factor(s) in order to reduce morbidity/prevent mortality

Non-drug treatment

  • Ensure clear airway by tilting the head backwards, lifting the chin and exploring to remove foreign bodies/dentures
  • Remove wears/ornaments which may negate the above

Basic life support (CPR)

  • Ensure that patient is lying on a firm/hard surface
  • Cardiac massage (80-100 per minute)
  • Assisted ventilation using a masked ambu bag
  • Twice in succession for every 15 cardiac massages (once every 5″massage when 2 people are in attendance)
  • Watch out for spontaneous respiration during this exercise

Advanced life support

  • Intubation with an endotracheal tube
  • Defibrillation/cardioversion for patients with ventricular fibrillation/ventricular tachycardia
  • Defibrillate with 200 J shock.
  • Additional shock up to 360 J may be required
  • Epinephrine (adrenaline) 1mg
    intravenously after failed defibrillation
  • Repeat defibrillation
  • Insert intravenous line
  • Monitor arterial blood gases

Drug treatment

Sodium bicarbonate 1 milliequivalent/ kg

  • Additional 50% of this dose every 10 to 15 minutes as deemed clinically appropriate

Lidocaine 1 mg/kg intravenously if there is unstable cardiac electrical activity. Repeat as required
Other antiarhythmic drugs if necessary
For cardiac arrest secondary to bradyarrhythmias orĀ  asystole:

  • Continue CPR
  • Insert intravenous line

Prevention

  • Family and community basic support education