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.
- an adjunct to preoxygenation: used to prolong oxygenation after optimal preoxygenation
- low cost in terms of resources and set-up
- 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
- severe maxillofacial trauma
- obstructed nares
- nasal cannula
- second oxygen source, e.g. mobile O2 tank
- 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.
- 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.
- Attach the nasal cannula to a separate oxygen source at 15L.
- 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 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
- Surgical airways
- 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.
- 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.