Table 1: Baseline demographic and clinical characteristics of study subjects.

PECS II group ()Control group ()

Age (years)45.4 ± 9.945.2 ± 11.9
BMI (kg/m2)22.8 ± 2.823.9 ± 3.1
ASA class (I/II)36 (90.0%)/4 (10.0%)29 (76.3%)/9 (23.7%)
Neoadjuvant CTx6 (15.0%)6 (15.8%)
Surgical time (min)93.5 ± 19.989.7 ± 24.9
Intraoperative remifentanil dosage (μg)491.0 (440.0; 571.0)477.0 (420.0; 600.0)
Tumor location (left/right)14 (35.0%)/26 (65.0%)21 (55.3%)/17 (44.7%)
Tumor location (quadrant)
 UOQ/LOQ11 (27.5%)/7 (17.5%)15 (39.5%)/7 (18.4%)
 UIQ/LIQ12 (30.0%)/3 (7.5%)7 (18.4%)/3 (7.9%)
 12 o’clock/6 o’clock5 (12.5%)/0 (0.0%)1 (2.6%)/1 (2.6%)
 3 o’clock/9 o’clock0 (0.0%)/2 (5.0%)2 (5.2%)/1 (2.6%)
 Subareolar0 (0.0%)1 (2.6%)

Data are expressed as mean ± SD (standard deviation), number (%), or median (interquartile range). BMI, body mass index; ASA, American Society of Anesthesiologists Physical Status Classification; CTx, chemotherapy; UOQ, upper outer quadrant; LOQ, lower outer quadrant; UIQ, upper inner quadrant; LIQ, lower inner quadrant.