Ray tackles the exploding nasal cannula. This is a can’t miss lecture on the value of pre-oxygenation, the immense significance of PEEP, the most iconic description of the oxyhemoglobin curve, and so much more. You WILL change your practice after this!

1. An Update to
Preoxygenation:
Nasal Cannulas don’t explode and PEEP is your best friend
Raymond Che

4. Conflicts of Interest
• None

5. Objectives
• Understand the purpose of PreOx and traditional technique
• Obtain Working knowledge of shunt physiology
• Thoroughly understand the role or PEEP in PreOx
• Incorporate PEEP effectively
• Encourage routine use of a nasal cannula

9. Standard Routine
Spontaneously Breathing Pt (Plan A)
• NRB at 15 L/min
• ~3 mins1
• Or 8 large Breaths1
Apneic Pt or (Plan B)
• BVM >15 L/min with PEEP 5-89
• Tight fitting mask seal
• ~3 mins is ideal
Some patients do not even receive preoxygenation

10. Hmm….
• 47% of all intubated
patients experience critical
desaturation during the
peri-intubation phase.4
• 10-25% result in severe
hypotension8
• 25% result in severe
hypoxemia8
• 2% result in cardiac arrest8
Severe
Hypotension
Severe
Hypoxemia
Cardiac arrest
No Severe
Events
ADVERSE PERI-INTUBATION EVENTS

11. Something Needs to
Change

12. Utilizing the PEEP Valve
• Turns a BVM into a potent tool
• Adds resistance during the expiratory phase
• BONUS
• Also acts as a one way valve
• Patient can now breath higher FiO2 spontaneously

14. BOOP

15. Mask Seal Is Key
ZEEP is Detrimental

16. 21% O2
50% O2
1

17. Why do We Care about PEEP?
• Positive End Expiratory Pressure (PEEP) has the most profound effect
on oxygenation2
• Especially patients with physiological shunt3
• Patient will reach adequate SpO2 Faster4,5
• Patient MAY maintain higher saturation for longer4
• Increases Mean Airway Pressure

18. Paw =
(Ti x PIP)+
Ttotal
______________________
(Te x PEEP)

19. Physiologic shunt
• alveoli are perfused as normal, but
ventilation fails to supply the perfused
region
• Think Restrictive disease processes
• Pneumonia
• Pulmonary Edema
• Atelectasis
• Fibrosis

25. Nasal Cannula is Your Friend
• 15 L/min NC augments Oxygenation
• Pressurizes the BVM
• Maintains the engagement of the PEEP valve
• Patient can be apneic and still have PEEP
• Compensates for Mask leak6
• Apneic Oxygenation?
• WOW that is so much Flow

27. Brainard et al: A Randomized Trial on Subject Tolerance and the
Adverse Effects Associated With Higher- versus Lower-Flow
Oxygen Through a Standard Nasal Cannula
• Results
• All 77 of the participants (100%) were able to tolerate 10 minutes at both
flow rates. Participants rated the higher-flow nasal cannula oxygen as a mean
of 25 mm (SD 20 mm) more uncomfortable than the lower-flow nasal cannula
oxygen. One minute after the oxygen was discontinued, the mean difference
in discomfort between the flow rates was a clinically insignificant 9.8 mm (SD
17 mm) more uncomfortable. There were no adverse events.
• Conclusion
• Participants were able to tolerate higher-flow nasal cannula oxygen for 10
minutes without difficulty. Higher-flow nasal cannula oxygen at 15 L/minute
was associated with some discomfort, but the discomfort quickly dissipated
and caused no adverse events.
All 77 of the participants (100%) were able to tolerate 10 minutes
discomfort between the flow rates was a clinically
insignificant
no adverse events

28. Compensation of Mask Leaks6
Treatment 3TV 8DB p value
1. p values < 0.008 considered significant (post hoc Bonferroni correction after Friedman test
α = 0.05/6 = 0.008).
With good mask seal
Standard pre-
oxygenation
83.0 (7.1) 78.1 (9.6) 0.005
Standard plus nasal
prongs
86.5 (6.9) 74.2 (7.3) < 0.001
Standard plus oxygen
flush
91.2 (3.8) 80.4 (7.5) < 0.001
With simulated mask leak
Standard 74.7 (9.3) 57.5 (6.2) < 0.001
Standard plus nasal
prongs
85.8 (9.7) 66.5 (12.5) < 0.001
Standard plus oxygen
flush
91.5 (4.8) 73.9 (10.1) < 0.001

29. However
Nasal Cannula Must be set Greater than 10 L/min
< than 10 will result in inefficient denitrogenation12
< than 10 is not enough flow to offset mask leak.11

30. Passive Apneic Oxygenation
• What is this?
• Leaving NC during
laryngoscopy to passively
allow that natural
diffusion gradient of A/C
membrane to absorb O2.
• Studies conflict and is no uniform consensus on its benefits7
• Appears proven to be beneficial to patients with normal lung function
• Intubated for protection

31. Who cares?
• Consider7
• Minimal risk
• Ease of use
• Known Benefits
• Mask Leak Compensation6
• Continuous actuation of PEEP valve (CPAP)
• Possible Benefits7
• Increased oxygenation
• Reduced risk of hypoxia
• Boosts preox speed11

32. Weingart’s Rule of 15’s1
15 L/min BVM
15 L/min NC
Up to 15 PEEP
Goal is to achieve SpO2 as close to 100% as possible

33. Prehospital considerations
• Oxygen supply at 15 L/min
• Full H-Cylinder will last 7.6 hours
• Full D-Cylinder will last 23.5 Minutes

34. Three things to take away
• Intubation is high risk
• BVM+PEEP+NC with good mask seal is amazing
• Always use a 15 L/min Nasal cannula

35. References
1. Weingart, S. D., & Levitan, R. M. (2012). Preoxygenation and Prevention of Desaturation During Emergency Airway Management. Annals of Emergency Medicine, 59(3)
2. Oliven, A., Taitelman, U., Zveibil, F., & Bursztein, S. (1980). Effect of positive end-expiratory pressure on intrapulmonary shunt at different levels of fractional inspired
oxygen. Thorax, 35(3), 181-185. doi:10.1136/thx.35.3.181
3. Villar, J., Kacmarek, R. M., Pérez-Méndez, L., & Aguirre-Jaime, A. (2006). A high positive end-expiratory pressure, low tidal volume ventilatory strategy improves outcome in
persistent acute respiratory distress syndrome: A randomized, controlled trial*. Critical Care Medicine, 34(5), 1311-1318. doi:10.1097/01.ccm.0000215598.84885.0
4. Glossop, A. J., & Esquinas, A. M. (2016). Preoxygenation by spontaneous breathing or noninvasive positive pressure ventilation with and without positive end-expiratory
pressure. European Journal of Anaesthesiology, 33(2), 143-144.
5. Barlow, D. S., Macklin, S., Evans, J., Carrera, A. M., & Seong, C. W. (2016). non-invasive ventilation achieves faster preoxygenation than standard high flow oxygen and is well
tolerated: a randomised controlled trial. Anesthesia & Analgesia, 123, 675-676.
6. Russell, T., Ng, L., Nathan, E., & Debenham, E. (2014). Supplementation of standard pre-oxygenation with nasal prong oxygen or machine oxygen flush during a simulated
leak scenario. Anaesthesia, 69(10), 1133-1137. doi:10.1111/anae.12630
7. Riddell, A. (2017). The Effect of Apneic Oxygenation on Reducing Hypoxemia During Rapid Sequence Induction and Intubation in the Acutely Ill or Injured. Advanced
Emergency Nursing Journal, 39(4), 309-317. doi:10.1097/tme.0000000000000168
8. Lapinsky, S. E. (2015). Endotracheal intubation in the ICU. Critical Care, 19(1)
9. Hansen, J. K., Anthony, D. G., Li, L., Wheeler, D., Sessler, D. I., & Bashour, C. A. (2014). Comparison of Positive End-Expiratory Pressure of 8 versus 5 cm H2O on Outcome
After Cardiac Operations. Journal of Intensive Care Medicine, 30(6), 338-343. doi:10.1177/0885066613519571
10. Brainard, A., Chuang, D., Zeng, I., & Larkin, G. L. (2015). A Randomized Trial on Subject Tolerance and the Adverse Effects Associated With Higher- versus Lower-Flow Oxygen
Through a Standard Nasal Cannula. Annals of Emergency Medicine, 65(4), 356-361. doi:10.1016/j.annemergmed.2014.10.02
11. Mcquade, D., Miller, M. R., & Hayes-Bradley, C. (2017). Addition of Nasal Cannula Can Either Impair or Enhance Preoxygenation With a Bag Valve Mask. Anesthesia &
Analgesia, 1. doi:10.1213/ane.0000000000002341
12. Hayes-Bradley, C., Lewis, A., Burns, B., & Miller, M. (2016). Efficacy of Nasal Cannula Oxygen as a Preoxygenation Adjunct in Emergency Airway Management. Annals of
Emergency Medicine, 68(2), 174-180. doi:10.1016/j.annemergmed.2015.11.012