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DEFIBRILLATOR


DEFIBRILLATOR:

  •  Ventricular Fibrillation: Ventricular fibrillation is a serious cardiac emergency resulting from asynchronous contraction of the heart muscles.

  • This uncoordinated movement of the ventricle walls of the heart may result from coronary occlusion, from electric shock or from abnormalities of body.

  • Because of this irregular contraction of the heart muscles, the ventricles cannot pump the blood effectively. It results in Life threatening condition.
  • Cardiac Arrhythmia: Any disturbance in the heart’s normal rhythmic contraction is called an arrhythmia. Mainly two types:
              1.        Tachycardia:An increase in Heart rate above normal limit is called Tachycardia.
              2.        Bradycardia:A decrease in Heart rate below normal limit is called Bradycardia.
  •  Need/Principle of Defibrillator: Ventricular fibrillation and Cardiac arrhythmia can be    converted into a more efficient rhythm by applying a high energy shock to the heart. This sudden electric shock across the heart causes all muscles to contract simultaneously.
  • The instrument used to give the shock is called a Defibrillator.
      


  •   Types of Defibrillator:


1.      Manual External Defibrillator: Machine and electrodes are external to the patient. Electrodes are placed on the chest and electric shock is delivered to the patient.
2.      Manual Internal Defibrillator: Machine is external and electrodes are held directly on the heart while thoracic cavity opens and shock is delivered.
                         3.      Automatic External Defibrillator(AED):Machine and electrodes     are external to the patient and electrodes are attached to the patient. Shock is delivered to the patient automatically when abnormal condition arises.
4.      Implantable Defibrillator: Machine and electrodes are implanted inside the patient’s
body and automatically deliver the shock when abnormal condition arises.
 
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