RAPID SEQUENCE INTUBATION “Rapid Sequence Intubation (RSI) is the virtually simultaneous administration, after preoxygenation, of a potent sedative agent and a rapidly acting neuromuscular blocking agent to facilitate rapid tracheal intubation without interposed mechanical ventilation.” Ron Walls, MD Manual of Emergency Airway Management · RSI is the cornerstone of emergency airway management. · RSI is predicated on the fact that the patient has not fasted prior to intubation, and is therefore at risk for aspiration of gastric contents. · The purpose of RSI is to render the patient unconscious and paralyzed and then to intubate the trachea without interposed assisted ventilation. · RSI has a very high success rate; approximately 99% in most cases. INDICATIONS FOR INTUBATION 1. Failure of airway maintenance or protection 2. Failure of ventilation or oxygenation 3. Impending airway obstruction RSI THE SEVEN P’s 1. Preparation zero minus 10 mins 2. Preoxygenation zero minus 5 mins 3. Pretreatment zero minus 3 mins 4. Paralysis with induction zero 5. Protection and positioning zero plus 20-30 secs 6. Placement with proof zero plus 45 seconds 7. Postintubation management zero pluz 1 minute 1. PREPARATION Assessment of potential airway management difficulties LEMON · Look externally · Evaluate 3-3-2 · Mallampati score · Obstruction · Neck mobility Physical signs | Less difficult airway | More difficult airway | Look externally | - Normal face and neck
- No face or neck pathology
| - Abnormal face shape
- Sunken cheeks
- Edentulous
- "Buck teeth"
- Receding mandible
- "Bull-neck"
- Narrow mouth
- Obesity
- Face or neck pathology
| Evaluate the 3-3-2 rule | - Mouth opening > 3F
- Hyoid-chin distance > 3F
- Thyroid cartilage-mouth floor distance > 2F
| - Mouth opening < 3F
- Hyoid-chin distance < 3F
- Thyroid cartilage-mouth floor distance < 2F
| Mallampati | - Class I and II (can see the soft palate, uvula, fauces +/- faucial pillars)
| - Class III and IV (can only see the hard palate +/- soft palate +/- base of uvula)
| Obstruction | | - Pathology within or surrounding the upper airway (e.g. peri-tonsillar abscess, epiglottis, retro-pharyngeal abscess)
| Neck mobility | - Can flex and extend the neck normally
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PREPARATION · At least one reliable IV · Monitor, pulse oximeter · Suction · Drugs ready to administer · Functioning laryngoscope with a selection of blades · ET tube with stylet, balloon cuff tested · Assistants 2. PREOXYGENATION · Essential to avoid bagging, which increases risk of aspiration in a non-fasted patient · Creates oxygen reservoir in blood to allow for a brief period of apnea · Pulse oximetry 3. PRETREATMENT LOAD · Lidocaine: for reactive airway disease or increased ICP. Blunts reflex rise in ICP and reflex bronchospasm. · Opioid ( Fentanyl): used when sympathetic responses should be blunted ( Increased ICP, aortic dissection, intracranial hemorrhage, cardiac ischemia, etc.) Attenuates reflex tachycardia and HTN. · Atropine : For Children 8 yrs or less. Children and infants tend to have a more pronounced vagal response to laryngoscopy, which can result in bradycardia. For this reason, the current recommendation for children younger than 1 year undergoing direct laryngoscopy is administration of atropine 0.02 mg/kg, independent of succinylcholine use. · Defasciculation: Before succinylcholine if patient has an increased ICP, penetrating globe injury. Rocuronium 0.06 mg/kg or Vecuronium 0.01 mg/kg 3 mins before administration of succinylcholine to prevent fasciculations. Drug Name Generic (Trade) | Adult Dose | Onset of Action | Duration of Action | Advantages | Cautions | Fentanyl | 1-2 mcg/kg slow IV push (over 1-2 min) | Immediate | 0.5-1 h | Primary pretreatment drug to provide sedation and analgesia; decreases hypertensive response to intubation | Hypotension; chest wall rigidity at high doses (ie, >15 mcg/kg) | Lidocaine (Xylocaine) | 1.5 mg/kg IV push 3 mins before induction | 1-2 min | 10-20 min | Useful in patients with asthma/COPD to decrease hypertensive response | Hypotension | Atropine | 0.02 mg/kg (usually about 0.4 mg) IV push Typically administered for pediatric patients ≤8y
| 2-4 min | Up to 4 h | Antisialagogue | Tachycardia | Vecuronium (Norcuron) | Defasciculating dose: 0.01 mg/kg IV push (typically about 1 mg, or 10% of intubation dose) | | | Decreases fasciculation and potassium release from cells; particularly useful if intend to use succinylcholine | Avoid higher doses that may produce paralytic effect | Rocuronium (Zemuron) | Defasciculating dose: 0.06 mg/kg IV push (typically about 10% of intubation dose) | | | Decreases fasciculation and potassium release from cells; particularly useful if intend to use succinylcholine | Avoid higher doses that may produce paralytic effect |
The benefits of some pretreatment drugs (e.g. lidocaine) are contested. Pretreatment medications are therefore sometimes omitted during RSI. 4. PARALYSIS WITH INDUCTION A rapidly acting induction agent is given to induce unconsciousness, immediately followed by a neuromuscular blocking agent (NMBA). Drug Name Generic (Trade) | Adult Dose | Onset of Action | Duration of Action | Advantages | Cautions | Midazolam (Versed) | 0.1 mg/kg IV | 2-3 min | up to several hours | Amnesia prior to procedure. Impairs memory in 90% of patients | delayed time to induction, predilection for hypotension at induction doses, and prolonged duration of action. | Etomidate (Amidate) | 0.3 mg/kg IV push (normal adult dose about 20 mg) | 0.5-1 min | 3-5 min | Does not alter hemodynamics or intracranial pressure (ICP); no histamine release; generally does not induce apnea; useful for patients with multiple trauma and hypotension (does not alter systemic BP) | Commonly causes myoclonus;
pain upon injection; adrenal suppression (typically no clinical significance);
does not suppress sympathetic response to laryngoscopy; nausea;
vomiting; lowers seizure threshold;
does not provide analgesia
| Propofol (Diprivan) | 2-3 mg/kg IV push Decrease dose if patient unstable | < 1 min | 3-10 min | Provides rapid onset and brief duration; cerebroprotective (decreases ICP); amnestic properties; extremely potent | Causes cardiovascular depression and hypotension; respiratory depression is dose-dependent | Succinylcholine (Anectine) | 0.3-2 mg/kg IV push (average dose 1.5 mg/kg) | 1 min | 4-6 min | Depolarizing NMB; drug of choice for emergency pediatric intubation; rapid onset (< 60 s) and brief duration of action; enhances nondepolarizing neuromuscular blocking effects | Increased serum potassium; muscle fasciculation; malignant hyperthermia; cardiac arrest in children with muscular dystrophy; dysrhythmia with multiple doses | Rocuronium (Zemuron) | 0.6-1 mg/kg IV push | < 1 min | 30-60 min | Nondepolarizing NMBA; minimal effect on hemodynamics; low incidence of histamine release (0.8%) | Duration prolonged with hepatic impairment |
5. PROTECTION AND POSITION · Apnea occurs within 30 seconds of administration of induction and paralyzing agents. · Fasciculations will occur if succinylcholine has been used . · Apply Sellick’s maneuver, position patient for optimal laryngoscopy. 6. PLACEMENT WITH PROOF · Assess mandible for flaccidity, perform intubation, confirm placement. - Confirm tube placement.
- Observe color change on a qualitative end-tidal carbon dioxide device.
- Use the 5-point auscultation method: Listen over each lateral lung field, the left axilla, and the left supraclavicular region for good breath sounds. No air movement should occur over the stomach.
7. POSTINTUBATION MANAGEMENT - Secure the ET tube into place.
- Initiate mechanical ventilation.
- Monitor vital signs; hypotension is common post-intubation.
- Obtain a chest radiograph.
- Assess pulmonary status.
- Note this modality does not confirm placement; rather, it assesses the height above the carina.
- Ensure that mainstem intubation has not occurred.
- Administer appropriate analgesic and sedative agents for patient comfort, to decrease O2 demand, and to decrease ICP. Benzos, propofol, opioids, etc.
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