BACKGROUND: Three common methods for preoxygenation are 3 min of tidal breathing, four deep breaths taken within 30 s (4DB), and eight deep breaths taken within 60 s (8DB). This report compares these three techniques in healthy volunteers. METHODS: Five healthy subjects breathed through a mouthpiece and wore a nose clip; oxygen was delivered at 180 l/min via a low-resistance T-piece. Each subject repeated each of the three oxygenation techniques four times. The end-tidal fraction of oxygen was measured, and the oxygen uptake at the mouth was measured breath by breath. The additional difference between oxygen uptake at the mouth during the period of breathing oxygen (as compared with that during air breathing) was taken to represent the total oxygen sequestrated into body stores. RESULTS: The mean +/- SD maximum end-tidal fraction of oxygen after the 4DB method was 0.83 +/- 0.09, which was significantly less than either after the 3-min method (0.92 +/- 0.01; P < 0.04) or after the 8DB method (0.91 +/- 0.04; P < 0.03). The mean additional oxygen taken up during oxygenation with the 4DB method was 1.67 +/- 0.45 l, which was significantly lower than with the 3-min method (2.23 +/- 0.85 l; P < 0.04) or with the 8DB method (2.53 +/- 0.74 l; P < 0.01). There were no significant differences for these variables between the 3-min and 8DB methods. CONCLUSIONS: For the physiologic measurements that were made, both the 3-min and the 8DB method are superior to the 4DB method. The 3-min and 8DB methods seem to be equally effective.
BACKGROUND: Three common methods for preoxygenation are 3 min of tidal breathing, four deep breaths taken within 30 s (4DB), and eight deep breaths taken within 60 s (8DB). This report compares these three techniques in healthy volunteers. METHODS: Five healthy subjects breathed through a mouthpiece and wore a nose clip; oxygen was delivered at 180 l/min via a low-resistance T-piece. Each subject repeated each of the three oxygenation techniques four times. The end-tidal fraction of oxygen was measured, and the oxygen uptake at the mouth was measured breath by breath. The additional difference between oxygen uptake at the mouth during the period of breathing oxygen (as compared with that during air breathing) was taken to represent the total oxygen sequestrated into body stores. RESULTS: The mean +/- SD maximum end-tidal fraction of oxygen after the 4DB method was 0.83 +/- 0.09, which was significantly less than either after the 3-min method (0.92 +/- 0.01; P < 0.04) or after the 8DB method (0.91 +/- 0.04; P < 0.03). The mean additional oxygen taken up during oxygenation with the 4DB method was 1.67 +/- 0.45 l, which was significantly lower than with the 3-min method (2.23 +/- 0.85 l; P < 0.04) or with the 8DB method (2.53 +/- 0.74 l; P < 0.01). There were no significant differences for these variables between the 3-min and 8DB methods. CONCLUSIONS: For the physiologic measurements that were made, both the 3-min and the 8DB method are superior to the 4DB method. The 3-min and 8DB methods seem to be equally effective.
Authors: J Adam Law; Laura V Duggan; Mathieu Asselin; Paul Baker; Edward Crosby; Andrew Downey; Orlando R Hung; George Kovacs; François Lemay; Rudiger Noppens; Matteo Parotto; Roanne Preston; Nick Sowers; Kathryn Sparrow; Timothy P Turkstra; David T Wong; Philip M Jones Journal: Can J Anaesth Date: 2021-06-08 Impact factor: 5.063
Authors: Aaron M Joffe; Ramesh Ramaiah; Eric Donahue; Richard E Galgon; Stephan R Thilen; Charles F Spiekerman; Sanjay M Bhananker Journal: BMC Anesthesiol Date: 2015-10-06 Impact factor: 2.217
Authors: J Adam Law; Natasha Broemling; Richard M Cooper; Pierre Drolet; Laura V Duggan; Donald E Griesdale; Orlando R Hung; Philip M Jones; George Kovacs; Simon Massey; Ian R Morris; Timothy Mullen; Michael F Murphy; Roanne Preston; Viren N Naik; Jeanette Scott; Shean Stacey; Timothy P Turkstra; David T Wong Journal: Can J Anaesth Date: 2013-10-17 Impact factor: 5.063