Table 1: Characteristics of patients in frequent and infrequent double lumen tube user groups.
Frequent ()
Infrequent ()
Age (years ± SD)
62 ± 14
49 ± 21
<0.001
Sex (M/F)
442/349
66/33
<0.05
ASA PS (1/2/3/4)
13/408/346/24
15/41/36/7
<0.005
Values for continuous data are reported as mean ± standard deviation and compared by testing. Categorical data were compared by analysis. Age is reported as mean ± standard deviation. ASA physical status is reported as the number of patients in each category. ASA PS: American Society of Anesthesiologists physical status classification.