What is the step-by-step medication guide for inducing Rapid Sequence Intubation (RSI), including first-line dosages and indications for alternative dosing?

From the Guidelines

Rapid sequence intubation (RSI) should be performed using a step-by-step medication guide, starting with preoxygenation for 3-5 minutes using 100% oxygen, followed by premedication with fentanyl (2-3 mcg/kg IV), then a sedative agent such as etomidate (0.3 mg/kg IV) or propofol (1-2 mg/kg IV), and finally a paralytic agent like succinylcholine (1.5 mg/kg IV) or rocuronium (1.0 mg/kg IV). The choice of sedative agent depends on the patient's hemodynamic stability, with etomidate preferred for unstable patients and propofol for stable patients 1. Ketamine (1-2 mg/kg IV) is a suitable alternative for asthmatic or hypotensive patients.

Medication Selection and Dosing

• Premedication: fentanyl (2-3 mcg/kg IV) to blunt sympathetic response, especially in patients with increased intracranial pressure or cardiovascular disease.
• Sedative agent:
  • Etomidate (0.3 mg/kg IV) for hemodynamically unstable patients.
  • Propofol (1-2 mg/kg IV) for stable patients.
  • Ketamine (1-2 mg/kg IV) for asthmatic or hypotensive patients.
• Paralytic agent:
  • Succinylcholine (1.5 mg/kg IV) for its rapid onset and short duration.
  • Rocuronium (1.0 mg/kg IV) if succinylcholine is contraindicated.

Special Considerations

• For obese patients, calculate dosing based on ideal body weight plus 40% of excess weight.
• Reduced doses may be necessary for elderly patients or those with hepatic or renal impairment.
• Always have backup airway equipment ready and consider having reversal agents available, particularly if using rocuronium (sugammadex 16 mg/kg IV for immediate reversal) 1.

Rationale

The selection of a sedative-hypnotic agent that attenuates hypotension during RSI is desirable, and etomidate has a favorable hemodynamic profile 1. However, the use of etomidate versus other induction agents does not differ significantly in terms of mortality or the incidence of hypotension or vasopressor use in the peri-intubation period and through hospital discharge 1. Recent guidelines recommend the use of a fast-acting muscle relaxant such as succinylcholine or rocuronium for RSI 1.

From the FDA Drug Label

To be administered only by experienced clinicians or adequately trained individuals supervised by an experienced clinician familiar with the use, actions, characteristics, and complications of neuromuscular blocking agents.

• Individualize the dose for each patient • Peripheral nerve stimulator recommended for determination of drug response and need for additional doses, and to evaluate recovery.

• Tracheal intubation: Recommended initial dose is 0.6 mg/kg. • Rapid sequence intubation: 0.6 to 1.2 mg/kg.

• Maintenance doses: Guided by response to prior dose, not administered until recovery is evident.

• Continuous infusion: Initial rate of 10 to 12 mcg/kg/min. Start only after early evidence of spontaneous recovery from an intubating dose.

The step-by-step medication guide for inducing Rapid Sequence Intubation (RSI) with rocuronium is as follows:

• Dosing: The recommended dose for Rapid Sequence Intubation is 0.6 to 1.2 mg/kg.
• Administration: To be administered only by experienced clinicians or adequately trained individuals supervised by an experienced clinician.
• Monitoring: Use a peripheral nerve stimulator to determine drug response and need for additional doses, and to evaluate recovery.
• Maintenance: Maintenance doses are guided by response to prior dose, and are not administered until recovery is evident.
• Continuous Infusion: The initial rate of 10 to 12 mcg/kg/min can be started only after early evidence of spontaneous recovery from an intubating dose. 2

From the Research

Step-by-Step Medication Guide for Rapid Sequence Intubation (RSI)

• Pretreatment:
  • Atropine, lidocaine, and fentanyl may be used, but their use has fallen out of favor due to limited evidence for their use outside of select clinical scenarios 3
• Induction:
  • Etomidate and ketamine are the most commonly used induction agents due to their favorable hemodynamic profiles 3
  • Etomidate has a rapid onset of action (5-15 seconds) and a duration of action of 5-15 minutes, with minimal respiratory or cardiovascular effects 4
  • Ketamine may produce more hypotension than etomidate in patients presenting with shock or sepsis 3
• Neuromuscular Blocking Agents:
  • Succinylcholine and rocuronium are the preferred agents, with minimal differences in first-pass success rates 3
  • Selection between the two is based on patient-specific factors, half-life, and adverse effect profiles 3
• Post-Intubation Sedation and Analgesia:
  • No specific guidelines are provided in the studies, but medication-assisted preoxygenation and awake intubation require different considerations for medication use 3

First-Line Dosages

• The studies do not provide specific first-line dosages for the medications used in RSI, but they discuss the importance of selecting the appropriate medication and dosage based on patient-specific factors 3, 5

Indications for Alternative Dosing

• Patients with hemodynamic instability or cardiac ischemia may benefit from etomidate due to its minimal cardiovascular effects 4
• Patients with head injuries may benefit from etomidate due to its cerebroprotective effects 4
• Patients with unknown or untreated medical conditions may benefit from etomidate due to its favorable safety profile 4
• Patients presenting with shock or sepsis may benefit from etomidate over ketamine due to its potential to produce less hypotension 3