Rapid Sequence Intubation (RSI)

Rapid Sequence Intubation (RSI) is a specialized intubation technique designed to secure the airway quickly and efficiently, primarily in patients with a high risk of aspiration. It involves the simultaneous administration of an induction agent and a neuromuscular blocking agent to facilitate intubation while minimizing the risk of complications.

Differences Between Normal Intubation and RSI

While both normal intubation and RSI aim to establish a secure airway, they differ significantly in their approach and application:

• Normal Intubation:
  • May involve sedation, but not always paralysis.
  • Typically used in controlled settings (e.g., operating room).
  • Allows for bag-mask ventilation (BMV) between induction and intubation.
  • Slower, more gradual process.
  • Lower risk of aspiration in controlled settings.
• Rapid Sequence Intubation (RSI):
  • Involves both a potent induction agent and a neuromuscular blocking agent (paralytic).
  • Primarily used in emergency settings.
  • Minimizes or eliminates BMV to reduce aspiration risk.
  • Very rapid sequence of steps.
  • Higher risk of aspiration if not performed correctly.

Indications for RSI

• Patients at high risk of aspiration (e.g., full stomach, decreased level of consciousness)
• Patients requiring immediate airway control (e.g., trauma, respiratory failure)
• Patients with conditions that may deteriorate rapidly

Contraindications

While RSI is a valuable technique, there are some situations where it may be contraindicated or require modification:

• Absolute Contraindications:
  • Known difficult airway where an awake intubation is safer.
  • Inability to ventilate with a bag-valve-mask (BVM).
• Relative Contraindications/Cautions:
  • Anticipated difficult airway.
  • Increased intracranial pressure (ICP) – requires careful medication selection and technique.
  • Hemodynamic instability – may require modified RSI with adjusted drug doses.
  • Pediatric patients – requires specialized knowledge and equipment.

The 7 Ps of RSI – A Step-by-Step Guide

RSI is a structured process involving seven key steps, remembered as the “”7 Ps””:

• 1. Preparation:
  • Goal: Ensure all necessary equipment, medications, and personnel are ready and organized.
  • Actions:
    • Gather and check all equipment: laryngoscope, blades, ETTs of various sizes, suction, oxygen, bag-valve-mask, monitors, etc.
    • Prepare medications: induction agents, paralytics, and any pretreatment drugs.
    • Assign roles: team leader, airway operator, medication administrator, monitor, etc.
    • Establish IV access.
    • Have a backup plan (e.g., supraglottic airway device) ready.
• 2. Pre-oxygenation:
  • Goal: Maximize the patient’s oxygen stores to prevent hypoxia during apnea.
  • Actions:
    • Administer 100% oxygen via a non-rebreather mask for 3-5 minutes.
    • Consider using a bag-valve-mask (BVM) with gentle ventilation if needed, but avoid prolonged ventilation.
    • Nasal cannula can be left on during intubation to provide apneic oxygenation.
• 3. Pretreatment:
  • Goal: Administer medications to mitigate adverse physiological responses to intubation.
  • Actions: Administer selected medications 2-3 minutes before induction:
    • Lidocaine (1-1.5 mg/kg IV): May attenuate increased ICP in head injury patients, but its use is controversial.
    • Fentanyl (3 mcg/kg IV): May blunt the hemodynamic response (hypertension, tachycardia), especially in patients with cardiac disease.
    • Atropine (0.02 mg/kg IV, minimum 0.1 mg): Historically used to prevent bradycardia in children, generally not used in adults unless bradycardia is present.
• 4. Paralysis with Induction:
  • Goal: Induce unconsciousness and muscle relaxation to facilitate intubation.
  • Actions:
    • Administer induction agent followed immediately by the neuromuscular blocking agent.
    • Induction Agents:
      • Etomidate (0.3 mg/kg IV): Preferred in hemodynamically unstable patients, minimal effect on ICP.
      • Ketamine (1-2 mg/kg IV): Useful in patients with bronchospasm or hypotension, may increase ICP.
      • Propofol (1.5-2.5 mg/kg IV): Rapid onset, but can cause significant hypotension.
    • Neuromuscular Blocking Agents (Paralytics):
      • Succinylcholine (1-1.5 mg/kg IV): Rapid onset (30-60 seconds), short duration (6-10 minutes), but has contraindications (e.g., hyperkalemia, malignant hyperthermia).
      • Rocuronium (1-1.2 mg/kg IV): Rapid onset (45-60 seconds), longer duration (30-60 minutes), fewer contraindications than succinylcholine.
• 5. Protection and Positioning:
  • Goal: Optimize visualization of the vocal cords and minimize the risk of aspiration.
  • Actions:
    • Position the patient in the “”sniffing position”” (flexion of the neck and extension of the atlanto-occipital joint).
    • Remove any oral debris or secretions with suction.
    • Apply cricoid pressure (Sellick maneuver) to help prevent passive regurgitation and aspiration. The evidence for its effectiveness is debated.
• 6. Placement of the ETT with Proof:
  • Goal: Insert the endotracheal tube (ETT) into the trachea and confirm its correct placement.
  • Actions:
    • Perform laryngoscopy to visualize the vocal cords.
    • Insert the ETT through the vocal cords.
    • Inflate the ETT cuff.
    • Confirm ETT placement using multiple methods:
      • Capnography: The most reliable method; look for sustained EtCO2 waveform.
      • Auscultation: Listen for bilateral breath sounds and absence of epigastric sounds.
      • Direct visualization: Seeing the ETT pass through the vocal cords.
      • Chest X-ray: To confirm final ETT position.
    • Secure the ETT to prevent dislodgement.
    • Document the ETT depth at the teeth.
• 7. Post-intubation Management:
  • Goal: Provide ongoing care and monitoring after intubation.
  • Actions:
    • Connect the patient to a mechanical ventilator and adjust settings.
    • Administer appropriate sedation and analgesia.
    • Continuously monitor vital signs, oxygen saturation, and EtCO2.
    • Obtain a chest X-ray to confirm ETT position.
    • Provide ongoing airway management, including suctioning as needed.
    • Monitor for complications (e.g., hypotension, pneumothorax, aspiration).

Medications Used in RSI

RSI involves the use of specific medications to achieve rapid unconsciousness and muscle relaxation.

• Induction Agents:
  • Etomidate: Hemodynamically stable, minimal effect on ICP.
  • Ketamine: Useful in patients with bronchospasm or hypotension, may increase ICP.
  • Propofol: Rapid onset, but can cause hypotension.
• Neuromuscular Blocking Agents (Paralytics):
  • Succinylcholine: Rapid onset, short duration, but has contraindications (e.g., hyperkalemia).
  • Rocuronium: Rapid onset, longer duration, fewer contraindications than succinylcholine.

Complications of RSI

• Hypoxia
• Aspiration
• Esophageal intubation
• Trauma (e.g., dental, airway)
• Arrhythmias
• Increased intracranial pressure