Table 4

- Comparison of in-group and between-group oxygen reserve index values.

TimeGroup 1 (n: 33)Group 2 (n: 33)P-value*
Mean±SDMedian (min.–max.)Mean±SDMedian (min.–max.)
T10.52±0.230.58 (0.09–1)b0.47±0.330.42 (0–1)b0.342
T20.27±0.200.29 (0–0.71)a0.39±0.310.33 (0–1)ab0.173
T30.20±0.220.12 (0–0.62)a0.24±0.220.25 (0–0.67)a0.427
T40.15±0.170.17 (0–0.48)a0.23±0.240.20 (0–0.9)a0.226
  • * Mann-Whitney U test, Friedman test, SD: standard deviation, Min: minimum, Max: maximum, Group 1: 3 min at normal tidal volume, Group 2: 30 s with the 4 deep vital capacity technique, T1: after preoxygenation, T2: immediately after intubation, T3: at the 3rd min after intubation, T4: at the 7th min after intubation, *P-value:comparison between groups. P-value: Compared within the group, a-b: There is no difference between times with the same letter in a group.