Table 7. Mean Delta SpO2 and BMI.

Delta SpO2 is the difference between preoperative baseline SpO2 at room air and SpO2 just prior to discharge. Mean delta SpO2 was 2.29 ± 1.78% in the group with BMI > 35 kg/m² versus 1.43 ± 1.99 with BMI ≤ 35 kg/m² (p=0.0254, unpaired two-tailed t-test).

SpO2: oxygen saturation; SD: standard deviation; N: number of patients

Two-tailed t-test *p=0.0254	Delta SpO2 mean	Standard deviation (N)
BMI ≤ 35  kg/m2	1.43 %	1.99 (69)
BMI > 35 kg/m2	2.29 %	1.78 (38)
Difference of mean Delta SpO2 between BMI ≤ 35 kg/m2 and BMI > 35 kg/m2 groups	0.86 %