113. Artificial Ventilation and Cardiopulmonary Resuscitation – Quiz

📌 Professor’s Notes: Quick Revision

High-yield revision notes for rapid review before university examinations.

• Artificial ventilation and cardiopulmonary resuscitation (CPR) are lifesaving procedures used to restore oxygenation, ventilation, and circulation during respiratory or cardiac arrest. Early intervention is essential because irreversible brain damage may occur within a few minutes of oxygen deprivation.
• Artificial ventilation is provided until spontaneous breathing returns. It is of two types:
  • Mechanical methods
    • Positive-pressure ventilation: Air or oxygen is delivered into the lungs under pressure. It is commonly used during anesthesia, surgery, and intensive care but may reduce venous return due to increased intrathoracic pressure.
    • Negative-pressure ventilation: Includes Drinker’s iron lung, Braggpaul chest cuirass, and Boyle’s apparatus, which produce ventilation by altering pressure around the thorax.
  • Manual methods: Include mouth-to-mouth, mouth-to-nose, and the Holger–Nielsen (back pressure–arm lift) method. These are used until advanced respiratory support becomes available.
• CPR is an emergency procedure performed in cardiorespiratory arrest to restore circulation and breathing. Common indications include myocardial infarction, ventricular fibrillation, severe arrhythmias, drowning, electric shock, pulmonary embolism, poisoning, trauma, airway obstruction, and cardiac tamponade. Cardiac arrest is suspected in an unresponsive patient with absent normal breathing and no carotid pulse.
• Objectives of CPR are to:
  • Maintain adequate oxygenation and ventilation.
  • Restore effective cardiac pumping and blood flow to vital organs.
• Basic Life Support (BLS) includes:
  • Assess responsiveness and call for emergency help.
  • Place the patient on a firm surface.
  • Clear the airway and open it using the head tilt–chin lift maneuver or jaw thrust if cervical spine injury is suspected.
  • Assess breathing and provide rescue breaths if required.
  • If no pulse is present, begin external chest compressions.
  • Compression depth in adults: 5–6 cm.
  • Compression rate: 100–120 compressions/minute.
  • Compression-to-ventilation ratio for a single rescuer: 30:2.
  • Minimize interruptions and allow complete chest recoil.
• Advanced Life Support (ALS) includes:
  • Defibrillation, the treatment of choice for ventricular fibrillation and pulseless ventricular tachycardia. Early defibrillation greatly improves survival.
  • Airway management with endotracheal intubation when indicated and administration of high-concentration oxygen.
  • Drugs such as adrenaline may be used during resuscitation. Sodium bicarbonate is reserved for selected conditions such as severe metabolic acidosis, hyperkalemia, or tricyclic antidepressant overdose.
• Adjunctive therapies include temporary cardiac pacing for refractory bradyarrhythmias. Atropine is used for symptomatic bradycardia but is not recommended for asystole. Older manual ventilation methods have limited use in modern practice.
• Post-resuscitation care aims to stabilize the patient, maintain adequate oxygenation and circulation, treat the underlying cause, monitor for hypoxic brain injury and cerebral edema, and use targeted temperature management in selected patients.