Chris Nickson Emergency Registrar

SCGH, November 2011

Preoxygenation and apneic oxygenation during emergency intubation

OWN THE OXYGEN!

A talk that pays homage tothe brilliant work of

Richard Levitan and Scott Weingart

http://lifeinthefastlane.com/2011/11/rr-in-the-fastlane-001/

3 Steps to Own the Oxygen!

①Preoxygenation• Why, how, and for how long?

②Apneic oxygenation• Why and how?• Positioning, ventilations and maneuvers• Paralytic agents

③Putting it into practice• Risk stratification and logistics

Why preoxygenate before you intubate?

Preoxygenation extends safe apnea time

during intubation

From Weingart and Levitan 2011

Goals of preoxygenation

①SaO2 100%

②Denitrogenate the lungs (big O2 reservoir)

③Oxygenate the blood (less important)

What is the best source of high FiO2 for preoxygenation?

Use a face mask with a reservoir and oxygen flow as high as possible

e.g. NRB mask with 15+ L/min

How long should you preoxygenate for before intubation?

If adequate respiratory drive:

3 minutesor

8 breaths with maximal inspiration and expiration

Is there a role for positive pressure in preoxygenation?

Yes!

Use CPAP or NIV or BVM with PEEP valve in patients with baseline SpO2 95% or less

How should you position the patient during preoxygenation?

Whenever possible, elevate the head

How long will it take a preoxygenated patient to desaturate?

Somewhere between 8 minutes and immediately!

From Walls RM, Murphy MF. Manual of Emergency Airway Management (2008), 3rd edition

What is the role of apneic oxygenation?

15 L/min via nasal cannulae extends the safe apnea time

Are ventilations during the apneic period an option?

Yes… if benefits > risks

consider if SpO2 90-95%

‘essential’ if SpO2 <90%

How should the patient be positioned,

and what maneuvers should be used,

during the apneic period?

Ear-to-sternal notch positioning

Consider nasal airway

Jaw thrust when apneic

(Forget cricoid!)

Position is everything!

Ear hole at the same height as the neck hole!

(aka sternal notch)

Scott Weingart - http://emcrit.org/

How does choice of paralytic agent affect oxygenation?

Suxamethonium leads to

shorter safe apnea times than rocuronium

http://lifeinthefastlane.com/2011/05/ruling-the-resus-room-004/

In Summary…

Oxygenate according to risk

Know the logistics…

Preoxygenation period

• Head up positioning• Ear-to-sternal notch position• Place nasal cannula• High flow oxygen: 15 L/min via NRB• Preoxygenate for 3 minutes with tidal breaths, or

8 maximal inspirations/ expirations• If hypoxic, consider:– CPAP (e.g. 5-15 cmH20 to achieve SO2 >98%)– BVM with PEEP valve

Apneic period

• Push sedative and roc• Commence 15 L/min oxygen via nasal cannula• Remove face mask• Maintain airway with jaw thrust• If hypoxic, consider:– CPAP– BVM (6 breaths/ min) with PEEP valve

Intubation period

• Leave the nasal cannula on at 15 L/min while you….

OWN THE AIRWAY!

Low risk

High risk

Hypoxic

http://lifeinthefastlane.com/2011/02/own-the-airway/

Remember to check out:http://emcrit.org/preoxygenation/

THE END