Read by QxMD icon Read

Effect of Apneic Oxygenation on Tracheal Oxygen Levels, Tracheal Pressure, and Carbon Dioxide Accumulation: A Randomized, Controlled Trial of Buccal Oxygen Administration

Andrew J Toner, Scott G Douglas, Martin A Bailey, Hans J Avis, Arani V Pillai, Michael Phillips, Andrew Heard
Anesthesia and Analgesia 2018 October 8

BACKGROUND: Apneic oxygenation via the oral route using a buccal device extends the safe apnea time in most but not all obese patients. Apneic oxygenation techniques are most effective when tracheal oxygen concentrations are maintained >90%. It remains unclear whether buccal oxygen administration consistently achieves this goal and whether significant risks of hypercarbia or barotrauma exist.

METHODS: We conducted a randomized trial of buccal or sham oxygenation in healthy, nonobese patients (n = 20), using prolonged laryngoscopy to maintain apnea with a patent airway until arterial oxygen saturation (SpO2) dropped <95% or 750 seconds elapsed. Tracheal oxygen concentration, tracheal pressure, and transcutaneous carbon dioxide (CO2) were measured throughout. The primary outcome was maintenance of a tracheal oxygen concentration >90% during apnea.

RESULTS: Buccal patients were more likely to achieve the primary outcome (P < .0001), had higher tracheal oxygen concentrations throughout apnea (mean difference, 65.9%; 95% confidence interval [CI], 62.6%-69.3%; P < .0001), and had a prolonged median (interquartile range) apnea time with SpO2 >94%; 750 seconds (750-750 seconds) vs 447 seconds (405-525 seconds); P < .001. One patient desaturated to SpO2 <95% despite 100% tracheal oxygen. Mean tracheal pressures were low in the buccal (0.21 cm·H2O; SD = 0.39) and sham (0.56 cm·H2O; SD = 1.25) arms; mean difference, -0.35 cm·H2O; 95% CI, 1.22-0.53; P = .41. CO2 accumulation during early apnea before any study end points were reached was linear and marginally faster in the buccal arm (3.16 vs 2.82 mm Hg/min; mean difference, 0.34; 95% CI, 0.30-0.38; P < .001). Prolonged apnea in the buccal arm revealed nonlinear CO2 accumulation that declined over time and averaged 2.22 mm Hg/min (95% CI, 2.21-2.23).

CONCLUSIONS: Buccal oxygen administration reliably maintains high tracheal oxygen concentrations, but early arterial desaturation can still occur through mechanisms other than device failure. Whereas the risk of hypercarbia is similar to that observed with other approaches, the risk of barotrauma is negligible. Continuous measurement of advanced physiological parameters is feasible in an apneic oxygenation trial and can assist with device evaluation.


You need to log in or sign up for an account to be able to comment.

No comments yet, be the first to post one!

Trending on Read

Available on the App Store

Available on the Play Store
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"