Test Out: Typical Induction

**Review Module 1 Induction PP notes

1. Preop

  • Review H/P

  • Chose appropriate plan

    • Typical induction is indicated for elective, outpatient, nonemergent cases where patient has been NPO appropriately.

  • Get consent for anesthesia services

  • Perform patient assessments:

    • Mallampati (Open mouth without AH; You want a grade 1 or 2 for PUSH)

      • He asked about this, each grade

    • Neck ROM

    • Mandibular protrusion (You want them to be able to bite over the top border of their upper lip; Grade A)

    • Additional:

      • Assess/look at teeth!

      • Assess history of PONV or motion sickness

      • Assess personal or family history of anesthetic complications

2. Preparation of Equipment
  • Machine check

    • Full machine check if first case of the day

    • Positive pressure leak test if between cases

  • Basic setup complete with SCOMMLADIE

    • Suction

      • Functioning, place under pillow, nearby

    • Circuit (with mask attached)

    • Oxygen

      • Pipeline + backup, full and appropriate pressures

    • Monitors

    • Machine

    • Laryngoscope

      • MAC (curved blade), size 3 for females or size 4 for males

    • Airway

      • 7.0 for females, 8.0 for males ETT with stylet inside and pre-filled syringe ready

      • One size smaller ETT (for if there is airway edema)

      • Different sized OPAs (in case there is tongue obstruction while masking)

      • LMA (for can’t ventilate can’t intubate situation)

      • Glidescope available if needed

    • Drugs

      • Fentanyl 50 or 100 mcg (to block sympathetic response to laryngoscopy)

        • Probably stick with 50 mcg more than 100 mcg. You really only need to use this with severely cardiac instable patients who cannot tolerate sympathetic response, but young people are able to tolerate this so even they do not necessarily need fentanyl.

      • Lidocaine 1-1.5 mg/kg (to block sympathetic response and to prevent propofol burn)

        • Extra: large AC vein is more effective for truly preventing propofol burning though

      • Propofol 1-2 mg/kg

        • Remember that propofol is in 10 mg/mL concentration; just remove a 0 from the total mg you calculate to get the volume

        • EX: You get a 70 kg patient and know you should give 140 mg propofol. You just give 14 mL.

      • Muscle relaxer: Roc 0.6-1 mg/kg (for typical induction)

        • For typical, 50 mg is standard dose (1 vial) for average weighted patient

        • For an RSI in a 80-100 kg patient, you can just do quick math with choosing 100 of Roc (2 vials)

        • **Based on ideal body weight, as you do not want to cause prolonged muscle paralysis

      • Emergency drugs

        • Esmolol for HTN (best antihypertensive since fast onset/offset d/t nonspecific plasma esterase metabolism)

        • Phenylephrine/Neo stick or ephedrine for hypotension

    • IV fluids/poles

    • Eye tape

3. Apply Monitors

  • Put on BP cuff —> pulse ox —> EKG electrodes

    • Continuous pulse ox and EKG, q5 min BP

  • Obtain baseline VSS

4. Patient positioning
  • Place patient into a sniffing position to align their oral, laryngeal, and pharyngeal axis’

    • Ear opening aligns with suprasternal notch

    • Ramping if the patient is obese

  • Adjust the bed level to a comfortable level for you to intubate

5. ACTIVE De-nitrogenation
  • Tight mask seal to provide 100% Fio2

    • Extra: This occurs because of Bernoulli’s effect: air entrainment through low pressure gaps, which then allows high velocity RA to enter and dilute the oxygen you are providing. Also, Dalton’s law indicates that less N2O automatically means more O2.

  • O2 flow 10 L/min (at least >5 L)

  • Opens APL valve (aka, ‘0’ so that the patient doesn’t feel suffocated)

  • Critical Actions (one of):

    • 3-8 forced vital capacities (max in, max out)

    • 3 minutes of normal tidal volume breathing

    • End-tidal oxygen >85%

  • Extra: This is beneficial bc it increases safe apneic time to 8 minutes, although less safe apneic time created for obese patients.

  • **Do not remove the mask off the patient; either use mask straps or someone will hold the mask to the patient’s face while you continue to administer induction meds. Otherwise, you are undoing all of your denitrogenation.

6. Administer Induction Drugs
  • Fentanyl (if giving), Lidocaine (if giving), Propofol

  • Ask the patient to open their eyes and take a deep breath in

  • Monitors for loss of eyelid reflex, indicating LOC (lightly flick the eyelashes)

  • Tapes eyelids to prevent corneal abrasions

7. Confirm Ability to Ventilate
  • Administer 3 effective breaths

  • With a tight mask seal and proper jaw thrust/head position

  • Verify presence of EtCO2.

    • If you have trouble bagging at this time, you can reposition or use OPA. Change something. Go to DL because you still need an airway!!

      • **Not NGT, lol

    • If you get laryngospasm, then you should do Larson’s maneuver to provide positive pressure to open the vocal cords; backup tx is sux. Bronchodilators/neb tx will not work because this is skeletal muscle!

      • This is most likely to occur in Geudel’s stage 2 (excitation/delirium)

8. Administer Muscle Relaxant
9. Provide Adequate Ventilation*****************
  • Provide positive pressure ventilation with <20 cm H2O

    • This prevents gastric insufflation, preventing aspiration

  • With a tight mask seal and proper jaw thrust/head position

  • ****Turn on some gas to maintain depth of anesthesia while waiting for the 2 minute onset time of Roc to pass (or 1 or 2 out of 4 twitches while monitoring Facial Nerve VII/orbicularis oculi)

    • You can do 1-2 MAC to maintain anesthetic depth

    • After 2 minutes have passed, turn off gas to prevent OR pollution and proceed to DL

10. Direct Laryngoscopy (DL)
  • Hold the laryngoscope with your left hand and with half your fingers wrapped around the actual blade

  • Open the mouth with your right middle finger and thumb, using scissor technique (at base of molars)

  • Insert atraumatically, not damaging teeth

  • Do a Right to left tongue sweep until you get to the Vallecula

    • MAC blade will go into vallecula for an indirect lifting of the epiglottis to view the glottis

  • Push away at 45 degrees towards the opposite wall

    • The actual laryngoscope blade should remain parallel to patient’s mouth though

  • State Cormack-Lehane Grade

    • He asks what 2a vs 2b is

11. Tracheal Intubation
  • Hold at the machine end for good maneuverability and do not lean forward

    • This would cause tunnel vision

  • With your right hand and into the right side of the mouth, insert the ETT atraumatically

  • STATE: “I see the ETT going through the vocal cords”

  • Go to the proper depth

    • 23 cm for male

    • 21 cm for females

    • This is 3-4 cm above carina

  • Remove stylet when tip is past the vocal cords (pull towards the chest, not straight up)

  • Inflate cuff to appropriate pressure

    • This is usually done by pressing on the pilot balloon and getting bounce back. You dont technically need a manometer because not available and the ETT will only be in for a relatively short amount of time, so any trauma will only be likely in highly susceptable patients (rare).

  • Extra: if you cannot intubate, go back to BMV. If you can do this, you still have time to change something. If you cannot intubate or cannot BMV, insert LMA.

12. Confirm placement
  • 1) Auscultation of bilateral midaxillary breath sounds; no gurgling over epigastrium

  • 2) Equal chest rise

  • 3) Fogging in the ETT

  • 4) Presence of EtCO2 over a minimum of 3 breaths.

    • PaCO2 to EtCO2 gradient should be 5-10 mmHg. This gradient exists because of alveolar dead space, which dilutes the exhaled CO2 and makes EtCO2 slightly lower than the actual arterial blood level. EX: If your EtCO2 is 35, your PaCO2 is likely 40–45 (which is perfect physiological normal).

  • EXTRA — Potential complications:

    • If you get unilateral breath sounds, you probably have endobronchial intubation and just pull back a little

    • If you get a bronchospasms, you can tx with volatile gas, inhaler treatments. Muscle relaxer will not work because this is smooth muscle!

      • Would be indicated by no breath sounds despite seeing the tube go through vocal cords. Or shark fin capnography.

    • If you tubed the goose, then Remove the tube and re-insert another ETT. Do not re-use the same ETT, you need a new one.

    • Funky ETT waveform can also be caused by kinking, incorrect reading (place a sensor into oropharynx for more accurate), high peak pressures (e.g., bronchospasm, COPD/asthma).

      • You would want to increase I:E ratio to 1:3 to prevent auto-peep or breath stacking, visible by increased baseline of the pressure waveform.

  • Secure ETT with tape

13. Establish Ventilation
  • Turning on ventilator (auto) mode and adjust to appropriate settings

    • Tidal volume 6-8 ml/kg of IDEAL body weight

      • So even though a 120 kg patient “should be” 840 mL, you would explode the lungs giving this amount of volume. So make sure you use ideal body weight, which is usually 70 kg and would be app. 500 mL

    • I:E ratio of 1:2

      • Can increase to 1:3 with obstructive lung disease (COPD, asthma); this would prevent auto-PEEP (breath stacking). 1:1 for ARDs to facilitate equal distribution of air through alveoli.

    • RR 10-12

    • Fio2 titrated to maintain Spo2 >94%.

      • But less than 100% to prevent absorption atelactasis and oxygen toxicity d/t free radicals

    • Minute ventilate should be 5-8 L/min

    • peak airway pressures <20-30 cm H2O

      • If very high, could indicate kink in tubing, patient biting on tube so deepen sedation, or even endobronchial intubation. Can increase to 1:3 I:E.

14. Begin Maintenance of Anesthesia
  • Adjust to minimal gas flow rates

    • You need 2 L/min for 2 MAC hours of sevo to prevent compound A

  • Turn on volatile agent to get 1 MAC expired concentration