Rapid Sequence Intubation (RSI)
Rapid Sequence Intubation (RSI) - An Update
The primary responsibility of an emergency physician managing a critically unstable patient is airway stabilization. Rapid Sequence Induction (RSI) is the preferred method for emergency airway management in all patients, except when a difficult airway is anticipated.
Definition: RSI involves the rapid or simultaneous administration of a sedative-hypnotic and a neuromuscular-blocking agent (NMBA), followed immediately by endotracheal tube placement before assisted ventilation.
The immediate objectives of RSI are to:
1) Minimize the risk of aspiration in vulnerable patients (e.g., those with a full stomach, ileus or bowel obstruction, gastroesophageal reflux disease, or increased intra-abdominal pressure).
2) Improve intubating conditions to decrease the rates of difficult or failed airways, esophageal intubation, and related complications.
A. Classical RSI
Promoted by Stept and Safar, it includes key elements such as:
- Preoxygenation with 100% oxygen.
- Administration of a specific induction dose.
- Use of thiopentone as the induction agent and succinylcholine as the neuromuscular blocker.
- Application of cricoid pressure to prevent bag-mask ventilation.
- Intubation using a cuffed tracheal tube.
- Availability of specialized equipment for failed intubation scenarios.
B. Modified RSI
With the evolution of RSI, newer drugs and techniques have been incorporated. Modifications to RSI may include:
- Utilizing various intravenous induction agents.
- Combining agents, with or without opioids.
- Adjusting doses of induction agents.
- Employing neuromuscular blockers other than succinylcholine.
- Permitting gentle mask ventilation during apnea.
These adjustments balance the increased risk of aspiration against benefits such as preventing hypoxia, respiratory acidosis, hemodynamic instability, and patient awareness.
Indication for RSI / Mechanical ventilation
Rapid Sequence Intubation (RSI) is a critical airway management technique that combines immediate unresponsiveness (induction agent) with muscular relaxation (neuromuscular blocking agent). It is the fastest and most effective means of controlling the emergency airway. Let’s explore the indications for RSI:
Indications for Intubation and Mechanical Ventilation:
- A: Threatened airway - Aspiration, Massive hemoptysis, hematemesis, facial injuries.
- B: Respiratory failure (hypercapnic or hypoxic), increased functional residual capacity (FRC), decreased work of breathing (WOB), secretion management, and pulmonary toilet. Also used to facilitate bronchoscopy.
- C: Hemodynamic instability - hypotension, shock - Minimize oxygen consumption and optimize oxygen delivery (e.g., in sepsis).
- D: Poor GCS, Unresponsive to pain, terminate seizures, prevent secondary brain injury.
- E: Temperature control (e.g., serotonin syndrome,NMS).
- F: For humanitarian reasons (e.g., procedures) and safety during transport (e.g., psychosis)
The 7 Ps
7 P's are the essential principles that guide this critical airway management technique. Let’s explore them:
Preparation:
- Gather necessary equipment, drugs, and personnel.Certainly! Here’s a table summarizing the essential equipment and setup for rapid sequence intubation (RSI):
Equipment and Setup Considerations Telemetry Continuous monitoring of cardiac rhythm. Pulse Oximetry Measures oxygen saturation (SpO₂). NIBP (Non-Invasive Blood Pressure) Regular blood pressure monitoring. Arterial Line (if time allows and/or hemodynamic instability) Provides continuous blood pressure monitoring and facilitates blood sampling. Capnography Monitors end-tidal CO₂ levels during intubation. IVs (preferably two) Ensure intravenous access for medications and fluids. Bag-Valve Mask For manual ventilation during intubation. Suction (check carefully!) Clears secretions and maintains a clear airway. Oxygen Supply Ensure a functioning oxygen source. Laryngoscope Essential for visualizing the vocal cords during intubation. Test the light and blades. Endotracheal Tubes (various sizes) Multiple tubes for different patient sizes. Check cuff inflation. Stylet Assists in tube insertion. Medications (drawn in labeled syringes) Sedation, neuromuscular blockade, vasopressors. Code Cart Nearby Immediate access to emergency medications and equipment. Alternative Airway Equipment Consider laryngeal mask airway (LMA) or cricothyroidotomy kit as backup options. Remember to verify the functionality of all equipment before starting the procedure. 🌟
- Ensure proper patient positioning.
- Establish intravenous access.
- Gather necessary equipment, drugs, and personnel.Certainly! Here’s a table summarizing the essential equipment and setup for rapid sequence intubation (RSI):
Preoxygenation:
- Administer 100% oxygen to maximize oxygen reserves.
- Preoxygenation helps prevent desaturation during the apnea phase.
- Ideally provide the patient with 3 minutes of 100% FiO2 at highest flow rate available (40-60 LPM).
- Higher flows are needed to wash out room air and prevent mixing in order to achieve >90% FiO2 delivered to the patient.
- Common devices: non-rebreather (NRB), bag-valve mask (BVM), Jackson-Rees bag.
- When using BVM, gentle PPV should be attempted to reduce gastric insufflation; provider can place cricoid pressure to compress the esophagus and reduce gastric insufflation as well.
- During apnea period, provide passive oxygenation / Apneic Oxygenation with NC at maximum flow (15 LPM) which is safe, inexpensive, and may extend the tolerated apnea period.
Pretreatment:
- Consider medications to mitigate adverse effects:
atropine 20 mcg/kg IV — prevent bradycardia in children.
lignocaine 1.5mg/kg IV — sympatholytic, neuroprotection in head injury; decrease airway reactivity in asthma.
fentanyl 2-3 mcg/kg IV — sympatholytic, neuroprotection in head injury and vascular emergencies (e.g. myocardial ischemia, aortic dissection, subarachnoid hemorrhage)
defasciculating dose of a non- depolarising neuromuscular blocker (e.g. rocuronium 0.1 mg/kg IV or vecuronium 0.01 mg/kg IV) — prevents fasciculations from Sch (e.g. TBI)
Paralysis with Induction:
- Administer induction agents (e.g., propofol, etomidate, ketamine).
Induction Agent (Sedative) Typical Bolus Dose (IV) Pharmacokinetics Notes Etomidate 0.3 mg/kg - Class: imidazole derivative
- MOA: GABA agonist
- Onset: 45-60 sec
- Duration: 3-5 min
- Minimal hypotension
- No histamine release.
- Reversible adrenal suppression
- May cause brief transient myoclonus during RSI
- No analgesia
Propofol 2 mg/kg - Class: alkylphenol derivative
- MOA: GABA agonist
- Onset: 30-60 sec
- Duration: 5-10 min
- Hypotension (dose-related)
- No analgesia
- Added benefit of bronchodilation
Midazolam (Versed) 1-4 mg - Class: benzodiazepine
- MOA: GABA agonist
- Onset: 2-3 min
- Duration: 2-4 hours
- Hypotension (less than propofol)
- Good amnestic properties
- No analgesia
- Anticonvulsant effects
Ketamine 1-2 mg/kg - Class: dissociative anesthetic, phencyclidine derivative
- MOA: NMDA antagonist among other effects
- Onset: 45-60sec
- Duration: 10-20 min
- Provides analgesia in addition to amnesia and sedation
- Good choice for awake intubations Hemodynamically neutral in most patients
- Added benefit of bronchodilation
- Caution with elevated ICP or systemic HTN
Remember to tailor the choice of induction agent based on the patient’s specific needs and clinical context.
- Followed by a neuromuscular blocking agent (e.g., succinylcholine, rocuronium).Certainly! Here’s a table summarizing the paralytic agents used in Rapid Sequence Intubation (RSI):
Paralytic Typical Bolus Dose Pharmacokinetics Advantages Disadvantages Succinylcholine (preferred agent in most circumstances) 0.6-1.5 mg/kg - MOA:Depolarizing agent, analog of ACh that binds to post-synaptic ACh receptors causing continuous stimulation
- Onset: 30-60 sec
- Duration: 8-12 min
- Rapid onset< Short acting
- Bradycardia (consider atropine)
- Increases ICP (avoid in CVA, spinal cord, and ocular injuries)
- Contraindicated with personal or family history of malignant hyperthermia.
- Avoid with rhabdo, burns, hyperkalemia, neuromuscular diseases.
Rocuronium 0.6-1.2 mg/kg (Based on IBW) - MOA: Non-depolarizing agent
- inhibits post-synaptic ACh receptors
- Onset: 60-90 sec Duration: 25-60 min
- Rapid onset, shorter than succinylcholine Shorter duration of action
- Minimal cardiovascular effects
- Relatively long acting: caution in difficult airway; can be reversed with neostigmine
Remember to choose the appropriate paralytic agent based on the patient’s specific needs and clinical context.
- Administer induction agents (e.g., propofol, etomidate, ketamine).
Protection and Positioning:
- Protect the cervical spine during intubation.
- Properly position the patient for optimal laryngoscopy.
Placement with Proof:
- Most commonly video-assisted (vs. direct visualization) endotracheal intubation.
- Visualize passage through the vocal cords.
- Advance ETT to desired level.
- Inflate cuff.
- Remove stylet.
- Secure ETT.
- If difficulty is encountered, do not repeatedly try with same blade, operator, etc.; call for help and try alternative approach and maintain mask ventilation with 100% oxygen.
- Confirm endotracheal tube placement using:
- Direct Visualization: Laryngoscopy.
- Capnography: Monitoring end-tidal CO₂ levels.
- Auscultation: Bilateral breath sounds.
- Post Intubation Care
Post Intubation Care Description Confirm Proper Placement Ensure the endotracheal tube (ETT) is correctly positioned in the trachea. Use multiple methods:
Auscultation: Listen for bilateral breath sounds.
Capnography: Monitor end-tidal CO₂ levels (the gold standard).
Visual Inspection: Check for equal chest rise during ventilation.Secure the Tube Fix the ETT in place to prevent accidental dislodgment. Use appropriate securing devices (e.g., tape, tube holders). Ventilation and Oxygenation Connect the patient to a mechanical ventilator. Adjust ventilation settings (tidal volume, rate, FiO₂) based on clinical needs.<br>- Maintain oxygen saturation (SpO₂) within the target range. Confirmatory Chest X-Ray Obtain a chest X-ray to verify ETT placement and assess lung fields.Look for proper depth and position of the tube. Post-Intubation Sedation and Analgesia Administer sedation and analgesia to keep the patient comfortable.Common choices include fentanyl, midazolam, or propofol. Monitor Vital Signs and Oxygenation Continuously assess heart rate, blood pressure, respiratory rate, and SpO₂. Address any hemodynamic instability promptly. Consider Additional Procedures Insert a nasogastric tube if needed. Obtain baseline laboratory tests (e.g., blood gases, electrolytes). Document the Procedure Record details of the intubation, tube size, depth, and any complications. Communicate this information to the team. Remember that post-intubation care is essential for patient safety and optimal outcomes. Regular assessments and adjustments are crucial during this phase
Remember that post-intubation care is essential for patient safety and optimal outcomes.
References
1. George B, Joachim N. Evolving Techniques in RSI: Can the Choice of Induction Agent Matter in Securing a Definitive Airway in Emergency Settings? Indian J Crit Care Med. 2022 Jan;26(1):15-17. doi: 10.5005/jp-journals-10071-24100. PMID: 35110838; PMCID: PMC8783234.
2. Stept WJ, Safar P. Rapid induction-intubation for prevention of gastric-content aspiration. Anesth Analg. 1970 Jul-Aug;49(4):633-6. PMID: 5534675.
3. Acquisto NM, Mosier JM, Bittner EA, et al. Society of Critical Care Medicine clinical practice guidelines for rapid sequence intubation in the critically ill adult patient. Crit Care Med. 2023 Oct;51(10):1411-1430. doi: 10.1097/CCM.0000000000006000.
4. Rapid-Sequence Intubation | ACEP.
5.https://hospitalhandbook.ucsf.edu/08-rapid-sequence-intubation/08-rapid-sequence-intubation
6. LITFL
7. Emcrit
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