Chapter 9-RSI (why and how to do it)

Chapter 9: Rapid Sequence Intubation (RSI)

INTRODUCTION TO RAPID-SEQUENCE INTUBATION (RSI)

  • Historically, RSI referred to Rapid Sequence Induction of anesthesia, aimed to minimize aspiration risk in surgical patients with a "full stomach."

  • In emergency medicine, RSI now specifically refers to Rapid Sequence Intubation, differing in the context of anesthesia versus airway management.

  • RSI is used to facilitate tracheal intubation quickly and safely, particularly in emergency situations.

  • Originally conceptualized to manage airways during emergency Caesarean sections, RSI has become standard practice in emergency medicine.

  • Use of specific pharmacologic agents during RSI creates suitable conditions for successful intubation.

  • Evidence suggests that with trained clinicians, RSI has higher success rates and fewer complications compared to other methods.

KEY POINTS

  • For those with necessary skills, RSI is the preferred method for tracheal intubation in emergencies unless contraindicated.

  • Emergency literature displays high success rates and low morbidity for RSI when performed by experienced clinicians.

  • Successful intubation alone does not equate to a successful clinical outcome.

  • Evidence supporting pretreatment medications prior to RSI is weak.

  • Focus should be on preventing hypoxia and hypotension during the procedure.

  • In case of expected rapid oxygen desaturation, gentle bag-mask ventilation (BMV) should occur while awaiting muscle relaxant effects.

  • Cricoid pressure can impair visualization during laryngoscopy and complicate BMV and extraglottic device (EGD) placement.

  • Laryngoscopy and intubation should only occur after muscle relaxants have taken effect.

CONTRAINDICATIONS FOR RSI

  • Inadequate Clinician Requirements:

    • The clinician must have proper knowledge, skills, and airway equipment available.

  • Anticipated Difficult Airway:

    • Avoid RSI if difficult intubation is predicted and BMV may also be challenging; consider awake intubation if possible, especially with obstructing airway pathology.

  • Unnecessary Procedure:

    • RSI is not warranted if facilitation isn’t needed; e.g., in patients who are already arrested. Assess airway first to identify possible difficulties; rescue techniques should have a high predicted success rate.

RSI IN EMERGENCIES: WHY USE IT?

  • Utilization of RSI in emergency settings and trauma management is increasing; endorsed by Advanced Trauma Life Support (ATLS).

  • Advantages of RSI:

    • Dependable on no patient cooperation; can be performed efficiently with proper setup.

    • Muscle relaxation aids conditions for direct laryngoscopy and intubation.

    • Cricoid pressure may reduce aspiration risks.

    • RSI drugs can mitigate undesired physiological responses (e.g., gagging, increases in Intracranial Pressure (ICP), heart rate, or blood pressure).

    • High success rates noted in experienced hands.

CURRENT STATE OF EVIDENCE ON RSI

  • Studies show growing evidence supporting RSI, yet some emergency departments (EDs) hesitate to adopt it consistently, citing concerns about safety with paralytics and involvement of non-anesthesiologists in anesthetic drug administration.

  • Debate exists regarding the appropriateness and safety of RSI.

  • Historical practices favored oro-tracheal intubation in cardiopulmonary arrest and nasotracheal in spontaneously breathing patients, often assisted by anesthesiologists in the ED.

  • By the late 1990s, over 95% of U.S. emergency medicine teaching programs incorporated neuromuscular agents for intubation.

  • ACEP's 1997 policy statement on RSI emphasized:

    • Training, knowledge, and experience are critical for attempting RSI.

    • Emergency departments must have immediate access to neuromuscular blockers and sedatives.

    • Quality review and patient monitoring in developing RSI policies is essential.

  • Data from trials supports RSI as effective and safe but highlights the need for robust management before, during, and after intubation.

  • Non-paralytic deep sedation commonly used outside OR settings yields poor intubating conditions in many emergency scenarios.

APPLICATION OF RSI: THE DEFINITION AND THE PROCESS

  • Rapid Sequence Intubation (RSI) involves pharmacologically inducing unconsciousness and muscle paralysis to facilitate tracheal intubation while reducing aspiration risk through cricoid pressure.

  • "Rapid-sequence" implies both the quick succession of agent administration and a swift transition from a conscious patient to intubation with a protected airway.

RSI: HOW TO DO IT

Steps in the RSI Process

  1. Preparation:

    • Assemble personnel and equipment; brief team on potential challenges.

    • Ensure suction is functional; medications prepared and labeled.

    • Establish optimal positioning for all involved.

  2. Preoxygenation:

    • Administer 100% oxygen for 3-5 minutes or have the patient take deep breaths to prolong pre-intubation safety.

    • Avoid positive pressure ventilation to prevent gastric insufflation unless spontaneous ventilation is inadequate.

  3. Fluid Loading and Pretreatment:

    • Administer fluids (10-20 mL/kg) before intubation to combat hypotension risks.

    • Medications used for pretreatment (if any) lack strong outcome data but may not cause harm.

  4. Induction and Pharmacologic Paralysis:

    • Administer an induction agent (e.g., propofol, etomidate) based on patient parameters.

    • Follow up with a muscle relaxant (e.g., succinylcholine or rocuronium) for paralysis.

    • Monitor apnea onset; gentle BMV may be required while maintaining oxygenation.

  5. Application of Cricoid Pressure:

    • Apply light cricoid pressure before initiation; increase pressure after unconsciousness for aspiration prevention.

    • Release pressure as needed during intubation or if complications arise.

  6. Intubation and Confirmation of Tube Placement:

    • Perform intubation within 30-45 seconds post-paralysis onset with visual confirmation of ETT placement.

  7. Postintubation Management:

    • Inflate cuff immediately, assess placement, and monitor vital signs, especially blood pressure.

    • Secure the ETT and consider sedation needs.

PEDIATRIC RSI DIFFERENCES

  • Use succinylcholine at a dose of 2 mg/kg for children; atropine use for bradycardia is less favored now.

  • Apnea time following succinylcholine will be shorter in younger children; rapid desaturation may occur due to higher basal oxygen consumption compared to adults.

SAMPLE RSIs

  • Sample timelines for adult (75 kg, systolic BP 140/) and pediatric (20 kg, systolic BP 100/) RSIs provided for quick reference.

SUMMARY

  • Effective RSI hinges on thorough planning, assessment, and preparation. Most outcomes favor rapid tube placement but clinicians must remain vigilant to complications, especially regarding cricoid pressure impacts. Postintubation management focuses on vital sign reassessment and tube security.

REFERENCES

  • Multiple studies and papers cited for establishing guidelines and support for RSI practices in emergency settings, including responses to historical practices and current outcomes.