MENU ▼
Read by QxMD icon Read
search
OPEN IN READ APP
JOURNAL ARTICLE

Preoxygenation With Flush Rate Oxygen: Comparing the Nonrebreather Mask With the Bag-Valve Mask

Brian E Driver, Lauren R Klein, Krista Carlson, Justin Harrington, Robert F Reardon, Matthew E Prekker
Annals of Emergency Medicine 2017 October 28
29089172

STUDY OBJECTIVE: Nonrebreather masks and bag-valve masks are used for preoxygenation before emergency intubation. Flush rate oxygen delivered with a nonrebreather mask is noninferior to bag-valve mask oxygen at 15 L/min. We seek to compare the nonrebreather mask with flush rate oxygen to a bag-valve mask with flush rate oxygen (with and without inspiratory assistance) and determine whether the efficacy of bag-valve mask with flush rate oxygen is compromised by a simulated mask leak.

METHODS: We conducted 2 prospective studies in healthy, adult volunteers. All devices in both studies used flush rate oxygen, achieved by rotating the flowmeter dial counterclockwise until it could not be rotated farther, which delivered oxygen at 40 to 60 L/min. Study 1 compared preoxygenation with nonrebreather mask to bag-valve mask (modified with a one-way exhalation port) with and without a simulated mask leak. Study 2 compared nonrebreather mask to bag-valve mask with inspiratory assistance. The primary outcome was FeO2. For each comparison, we prespecified a noninferiority margin of FeO2 for the nonrebreather mask (compared with the bag-valve mask, bag-valve mask with mask leak, and bag-valve mask with assistance) of 10%.

RESULTS: Thirty subjects were enrolled in study 1 and 27 subjects were enrolled in study 2. For study 1, mean FeO2 values for nonrebreather mask, bag-valve mask, and bag-valve mask with leak were 81% (95% confidence interval [CI] 78% to 83%), 76% (95% CI 71% to 81%), and 30% (95% CI 26% to 35%), respectively. FeO2 for the nonrebreather mask was noninferior to the bag-valve mask at flush rate (difference 5%; 95% CI -1% to 10%). FeO2 was higher for the nonrebreather mask compared with the bag-valve mask with a simulated mask leak (difference 51%; 95% CI 46% to 55%). For study 2, mean FeO2 values for nonrebreather mask and bag-valve mask with assistance were 83% (95% CI 80% to 86%) and 77% (95% CI 73% to 80%), respectively. FeO2 for the nonrebreather mask was noninferior to the bag-valve mask with assistance at flush rate (difference 6%; 95% CI 3% to 10%).

CONCLUSION: With flush rate oxygen, the nonrebreather mask is noninferior to the bag-valve mask, with and without inspiratory assistance. Bag-valve mask performed poorly with a mask leak, even with flush rate oxygen. Flush rate oxygen with a nonrebreather mask is a reasonable default preoxygenation method in spontaneously breathing patients with no underlying respiratory pathology.

Comments

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!

Related Papers

Available on the App Store

Available on the Play Store

Read Institutional Edition
Remove bar
Read by QxMD icon Read
29089172
×

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"