Untitled Quiz

Electrical Therapy

• Electrical therapy is a method of stimulating the body using electrodes placed on the skin.
• An electrical current is transmitted to these electrodes, causing the depolarization of sensory nerves and increasing muscle strength.
• This therapy is used to treat a variety of conditions, including muscle atrophy, pain, and paralysis.

Automated External Defibrillator (AED)

• An AED is a portable device that analyzes a person's heart rhythm and delivers an electric shock if needed.
• AEDs are used to treat sudden cardiac arrest (SCA) caused by ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT).
• There are two types of AEDs: semi-automatic and fully automatic.
• Semi-automatic AEDs require the user to press a button to deliver the shock, while fully automatic AEDs deliver the shock without user input.

Defibrillation

• Defibrillation is a common treatment for life-threatening cardiac arrhythmias, like VF and pulseless VT.
• It involves delivering a therapeutic dose of electrical energy to the heart using a defibrillator.
• Two types of defibrillators exist: impedance-based and current-based.
• Defibrillation is typically performed with either monophasic or biphasic waveforms.
• Monophasic defibrillators deliver a single electric pulse, while biphasic defibrillators deliver two pulses in opposite directions.
• Biphasic defibrillators often require lower energy levels than monophasic defibrillators.

Components of a Defibrillator

• Defibrillators have three main components:
  • The machine itself,
  • Paddle electrodes, and
  • Cables that connect the paddles to the machine.

Synchronized Cardioversion

• Synchronized cardioversion is a treatment used for unstable tachyarrhythmias.
• It involves delivering a synchronized electric shock to the heart.
• Before performing cardioversion, patients need to be prepared with:
  • Consent (if possible),
  • Pre-medication with sedatives and analgesics like midazolam, etomidate, ketamine, fentanyl, or morphine,
  • Monitoring, gel, and an emergency trolley.
• Energy levels can be adjusted based on the type of rhythm being treated – 50-100 J for narrow SVT, 120 J for irregular AF, 100 J for wide VT.
• The synchronized button on the defibrillator must be activated to ensure the shock is delivered in sync with the R wave or QRS complex.

Transcutaneous Pacing

• Transcutaneous pacing is used to treat symptomatic bradyarrhythmias that do not respond to atropine.
• Alternative treatments include IV adrenaline infusion (1-10mcg/min) or IV dopamine infusion (2-10mcg/kg/min).
• It is preferred in AMI with bradycardia to minimize the stress response caused by adrenaline or dopamine.

Paddle Placement for Transcutaneous Pacing

• Four common paddle positions are utilized:
  • Antero-lateral
  • Antero-posterior
  • Anterior-left infra-scapular
  • Anterior-right infra-scapular

Energy Levels for Defibrillation and Cardioversion

• Energy levels for defibrillation and cardioversion vary based on the rhythm being treated:
  • Ventricular fibrillation or pulseless ventricular tachycardia – 300 J monophasic or device-specific biphasic (150-200 J)
  • Atrial fibrillation – 100-200 J monophasic or 100-120 J biphasic
  • Atrial flutter and other SVTs – 50-100 J monophasic or 100-120 J biphasic
  • Ventricular tachycardia (with pulse) - 100 J monophasic or device-specific biphasic

Factors Influencing Defibrillation Success

• Factors that can affect defibrillation success:
  • Hairy chest
  • No gel medium
  • Gel smear between paddles
  • Body fat
  • Distance between paddles
  • Weight application on paddles (10 kg per paddle)
  • Serial shocks
  • Time lag between arrhythmia onset and shock

Defibrillation Contraindications

• Defibrillation is contraindicated in the following situations:
  • The patient’s desire not to be resuscitated has been clearly expressed and documented.
  • There is immediate danger to the rescuers due to the environment, patient location, or patient condition.

Defibrillation Side Effects

• The most common side effect of defibrillation is skin burns at the paddle placement areas.
• Unintentional shock, which can be painful, is another potential side effect, especially for people touching the patient during defibrillation.

Defibrillation Precautions

• Precautions for defibrillation include:
  • Awareness of oxygen and fire risks.
  • Proper technique to prevent charging or placing paddles directly onto the patient.
  • Never allowing oxygen flow directly onto the victim.
  • Proper care and maintenance of the defibrillator, including general checkout, testing, battery replacement, and cleaning.

Defibrillation vs. Synchronized Cardioversion

• Defibrillation delivers energy during any phase of the cardiac cycle and is used for patients who are pulseless. Higher energy levels are typically required.
• Synchronized Cardioversion delivers energy synchronized to the R waves or QRS complex, requiring lower energy levels. Used for patients who are conscious.

Troubleshooting Defibrillation Issues

• If defibrillation is unsuccessful, check the following:
  • Paddle or electrode position
  • Adequate skin contact
  • Consider changing the defibrillator pads.