Difference between revisions of "Apneic oxygenation"

(Apneic Oxygenation Procedure)
 
(References)
 
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==Overview==
 
==Overview==
'''Apneic oxygenation''' is a technique that prolongs "safe apnea time" (time until desaturation to SaO2=88-90%) after induction of apnea. This increases time for laryngoscopy/intubation.
+
*Technique to prolongs "safe apnea time" (time until desaturation to SaO2=88-90% after induction of apnea). This increases time for laryngoscopy/intubation.
*an ''adjunct'' to preoxygenation: used to prolong oxygenation after optimal preoxygenation
+
*Used as an ''adjunct'' to preoxygenation: used to prolong oxygenation after optimal preoxygenation
*low cost in terms of resources and set-up
+
*Low cost in terms of resources and set-up
 +
 
 
==Physiology==
 
==Physiology==
*gas exchange during apnea creates subatmopsheric pressure in the alveoli
+
*Gas exchange during apnea creates subatmopsheric pressure in the alveoli
**in healthy lungs, 200-250mL O2 per minute can be drawn into blood stream
+
**In healthy lungs, 200-250mL O2 per minute can be drawn into blood stream
**in the absence of ventilation (i.e. during apnea), only 10-20mL CO2 enters alveoli from bloodstream per minute, due to increased CO2 tension
+
**In the absence of ventilation (i.e. during apnea), only 10-20mL CO2 enters alveoli from bloodstream per minute, due to increased CO2 tension
**this causes a net decrease in gas in the alveoli
+
**This causes a net decrease in gas in the alveoli
*this gradient can draw air into the lungs, even absent diaphragmatic movement
+
*This gradient can draw air into the lungs, even absent diaphragmatic movement
*increases safe apnea time in healthy volunteers from 1 minute (room air) to 8-9 minutes
+
*Increases safe apnea time in healthy volunteers from 1 minute (room air) to 8-9 minutes
  
 
==Indications==
 
==Indications==
*intubation
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*[[Intubation]]
 +
 
 
==Contraindications==
 
==Contraindications==
*severe maxillofacial trauma
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*Severe maxillofacial trauma
*obstructed nares
+
*Obstructed nares
 +
 
 
==Equipment Needed==
 
==Equipment Needed==
*nasal cannula
+
*Nasal cannula
*second oxygen source, e.g. mobile O2 tank
+
*Second oxygen source, e.g. mobile O2 tank
 +
 
 
==Procedure==
 
==Procedure==
 +
#Start pre-oxygenation while sitting upright, only lay back once [[RSI]] drugs pushed.
 
#During preoxygenation, keep the nasal cannula on underneath your primary preoxygenation technique.
 
#During preoxygenation, keep the nasal cannula on underneath your primary preoxygenation technique.
 
#*This can be achieved whether you use a mask, NPPV, or BVM; a good seal can still be obtained. Alternatively, you can use the [[high flow nasal cannula]] technique for preoxygenation.
 
#*This can be achieved whether you use a mask, NPPV, or BVM; a good seal can still be obtained. Alternatively, you can use the [[high flow nasal cannula]] technique for preoxygenation.
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#After preoxygenation, leave the nasal cannula on after removing mask/NPPV/BVM. It should not get in the way of laryngoscopy.
 
#After preoxygenation, leave the nasal cannula on after removing mask/NPPV/BVM. It should not get in the way of laryngoscopy.
 
#*Consider taping cannula to face to prevent dislodgement.
 
#*Consider taping cannula to face to prevent dislodgement.
 +
 
==Complications/Limitations==
 
==Complications/Limitations==
*complications are limited and most can be quickly remedied by removing nasal cannula
+
*Complications are limited and most can be quickly remedied by removing nasal cannula
**if not well-positioned/attached, may complicate laryngoscopy
+
**If not well-positioned/attached, may complicate laryngoscopy
**high flow oxygen from nasal cannula is cold and dry; may not be well-tolerated by patient
+
**High flow oxygen from nasal cannula is cold and dry; may not be well-tolerated by patient
**extremely high flow oxygen (>70 L/M) may cause barotrauma
+
**Extremely high flow oxygen (>70 L/M) may cause barotrauma
**increased apnea time increases respiratory acidosis
+
**Increased apnea time increases respiratory acidosis
*not shown to improve saturation in critically ill patients
+
*Not shown to improve saturation in critically ill patients
 +
 
 
==See Also==
 
==See Also==
*[[EBQ:ED Preoxygenation]]
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{{Related Difficult Airway Pages}}
*[[Rapid sequence intubation]]
+
 
*[[Intubation]]
 
 
==External Links==
 
==External Links==
https://emcrit.org/pulmcrit/preoxygenation-apneic-oxygenation-using-a-nasal-cannula/
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*https://emcrit.org/pulmcrit/preoxygenation-apneic-oxygenation-using-a-nasal-cannula/
 +
 
 
==References==
 
==References==
 
<references/>
 
<references/>
*Moran C, Karalapillai D, Darvall J, Nanuan A. Is it time for apnoeic oxygenation during endotracheal intubation in critically ill patients? Critical care and resuscitation. 16(3):233-5. 2014.
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*Semler MW, Janz DR, Lentz RJ. Randomized Trial of Apneic Oxygenation during Endotracheal Intubation of the Critically Ill. American journal of respiratory and critical care medicine. 2015.
 
*Hayes-Bradley C, Lewis A, Burns B, Miller M. Efficacy of Nasal Cannula Oxygen as a Preoxygenation Adjunct in Emergency Airway Management. Annals of emergency medicine. 68(2):174-80. 2016.
 
*Lynn E. Teller, M.D., Christian M. Alexander, M.D., M. Jack Frumin, M.D., Jeffrey B. Gross, M.D.; Pharyngeal Insufflation of Oxygen Prevents Arterial Desaturation during Apnea. Anesthes 1988;69(6):980-982.
 
 
[[Category:Procedures]]
 
[[Category:Procedures]]
 +
[[Category:Critical Care]]

Latest revision as of 13:34, 7 October 2019

Overview

  • Technique to prolongs "safe apnea time" (time until desaturation to SaO2=88-90% after induction of apnea). This increases time for laryngoscopy/intubation.
  • Used as an adjunct to preoxygenation: used to prolong oxygenation after optimal preoxygenation
  • Low cost in terms of resources and set-up

Physiology

  • Gas exchange during apnea creates subatmopsheric pressure in the alveoli
    • In healthy lungs, 200-250mL O2 per minute can be drawn into blood stream
    • In the absence of ventilation (i.e. during apnea), only 10-20mL CO2 enters alveoli from bloodstream per minute, due to increased CO2 tension
    • This causes a net decrease in gas in the alveoli
  • This gradient can draw air into the lungs, even absent diaphragmatic movement
  • Increases safe apnea time in healthy volunteers from 1 minute (room air) to 8-9 minutes

Indications

Contraindications

  • Severe maxillofacial trauma
  • Obstructed nares

Equipment Needed

  • Nasal cannula
  • Second oxygen source, e.g. mobile O2 tank

Procedure

  1. Start pre-oxygenation while sitting upright, only lay back once RSI drugs pushed.
  2. During preoxygenation, keep the nasal cannula on underneath your primary preoxygenation technique.
    • This can be achieved whether you use a mask, NPPV, or BVM; a good seal can still be obtained. Alternatively, you can use the high flow nasal cannula technique for preoxygenation.
    • Normal adjunctive airway techniques/equipment (jaw thrust, oropharyngeal airway) remain useful. In particular, nasal trumpet can maintain patencny of at least one nare.
  3. Attach the nasal cannula to a separate oxygen source at 15L.
  4. After preoxygenation, leave the nasal cannula on after removing mask/NPPV/BVM. It should not get in the way of laryngoscopy.
    • Consider taping cannula to face to prevent dislodgement.

Complications/Limitations

  • Complications are limited and most can be quickly remedied by removing nasal cannula
    • If not well-positioned/attached, may complicate laryngoscopy
    • High flow oxygen from nasal cannula is cold and dry; may not be well-tolerated by patient
    • Extremely high flow oxygen (>70 L/M) may cause barotrauma
    • Increased apnea time increases respiratory acidosis
  • Not shown to improve saturation in critically ill patients

See Also

Airway Pages

External Links

References