Table 3 Correlation between BMI and peri-operative outcomes. (a) Ordinary least squares univariate linear regression of BMI as a continuous variable; (b) Analysis of BMI as a categorical variable (factor 1 BMI <25 (n = 36) vs. factor 2 BMI ≥25 (n = 54)) using ANOVA (continuous dependent variables) and chi-squared (binary dependent variables) statistics

Variable

r ²

Coefficient

p

 Aortic cross-clamp time

0.072

0.070

0.022

 CPB time

0.043

0.045

0.062

 Mechanical ventilation time

0.084

−0.295

0.039

 ICU stay

0.019

0.941

0.331

 Overall hospital stay

0.017

0.080

0.261

 Bleeding at 12 h

0.067

−0.003

0.019

 Bleeding prior to arrival on ICU

0.091

−0.010

0.031

 RBC transfusion

0.034

−1.790

0.190

 New-onset atrial fibrillation

0.067

−2.130

0.024

 Hospital-acquired pneumonia

0.048

2.870

0.113

Variable

f

Chi²

p

 Aortic cross-clamp time

3.43

-

0.068

 CPB time

4.93

-

0.029

 Mechanical ventilation time

3.60

-

0.064

 ICU stay

0.11

-

0.742

 Overall hospital stay

0.17

-

0.678

 Bleeding at 12 h

6.58

-

0.013

 Bleeding prior to arrival on ICU

4.51

-

0.039

 RBC transfusion

-

0.815

0.367

 New-onset atrial fibrillation

-

4.410

0.036

 Hospital-acquired pneumonia

-

5.400

0.020

 Renal dysfunction

-

0.159

0.690