Table 1.
Baseline characteristics of study population before and after propensity score matching.
| Overall Patients | After Matching | |||||
|---|---|---|---|---|---|---|
| Propofol | Sevoflurane | SMD | Propofol | Sevoflurane | SMD | |
| (n = 719) | (n = 1852) | (n = 717) | (n = 1410) | |||
| Age, year | 61.7 (11.4) | 60.7 (12.0) | 0.084 | 61.7 (11.4) | 61.8 (11.8) | 0.008 |
| Sex, female | 290 (40.3) | 797 (43.0) | 0.055 | 289 (40.3) | 597 (42.3) | 0.041 |
| BMI, kg/m2 | 24.1 (3.3) | 23.8 (3.4) | 0.078 | 24.1 (3.3) | 23.9 (3.4) | 0.035 |
| ASA | ||||||
| I | 179 (24.9) | 539 (29.1) | 0.094 | 178 (24.8) | 356 (25.3) | 0.009 |
| II | 485 (67.5) | 1139 (61.5) | 0.124 | 484 (67.5) | 934 (66.2) | 0.026 |
| III | 55 (7.7) | 166 (9.0) | 0.047 | 55 (7.67) | 120 (8.5) | 0.031 |
| IV | 0 (0) | 8 (0.4) | 0 (0) | 0 (0) | ||
| Current smoking | 70 (9.7) | 197 (10.6) | 0.029 | 70 (9.8) | 140 (9.9) | 0.005 |
| Heavy drinking | 58 (8.1) | 129 (7.0) | 0.042 | 58 (8.1) | 103 (7.3) | 0.03 |
| History of surgery | 169 (23.5) | 451 (24.4) | 0.019 | 168 (23.4) | 343 (24.3) | 0.021 |
| Comorbidities | ||||||
| Hypertension | 271 (37.7) | 633 (34.2) | 0.074 | 271 (37.8) | 512 (36.3) | 0.031 |
| Diabetes mellitus | 149 (20.7) | 321 (17.3) | 0.087 | 148 (20.6) | 273 (19.4) | 0.032 |
| Stroke | 18 (2.5) | 59 (3.2) | 0.041 | 18 (2.5) | 31 (2.2) | 0.021 |
| CAD | 26 (3.6) | 85 (4.6) | 0.049 | 26 (3.6) | 53 (3.8) | 0.007 |
| Heart failure | 1 (0.1) | 16 (0.9) | 0.103 | 1 (0.1) | 2 (0.1) | 0.001 |
| COPD | 18 (2.5) | 54 (2.9) | 0.028 | 18 (2.5) | 34 (2.4) | 0.007 |
| Preoperative test | ||||||
| Haemoglobin, g/dL | 13.4 [12.0, 14.5] | 13.0 [11.6, 14.3] | 0.071 | 13.4 [12.0, 14.5] | 13.0 [11.6, 14.4] | 0.074 |
| Albumin, g/dL | 4.4 [4.2, 4.7] | 4.4 [4.2, 4.6] | 0.039 | 4.4 [4.2, 4.7] | 4.4 [4.2, 4.6] | 0.024 |
| Creatinine, mg/dL | 0.81 [0.68, 0.95] | 0.80 [0.68, 0.94] | 0.021 | 0.81 [0.68, 0.95] | 0.81 [0.69, 0.94] | 0.005 |
| NLR | 2.1 [1.5, 2.9] | 2.1 [1.5, 2.9] | 0.037 | 2.1 [1.5, 2.9] | 2.0 [1.5, 2.8] | 0.012 |
| Neoadjuvant therapy | 99 (13.8) | 280 (15.1) | 0.038 | 98 (13.7) | 168 (11.9) | 0.053 |
| CCI | 4 [3, 5] | 4 [3, 5] | 0.002 | 4 [3, 5] | 4 [3, 5] | 0.019 |
| ECOG performance | ||||||
| 0 | 588 (81.8) | 1419 (76.6) | 0.127 | 586 (81.7) | 1148 (81.4) | |
| 1 | 126 (17.5) | 414 (22.4) | 0.121 | 126 (17.6) | 252 (17.9) | 0.008 |
| 2 | 5 (0.7) | 17 (0.9) | 0.025 | 5 (0.7) | 10 (0.7) | 0.008 |
| 3 | 0 (0) | 2 (0.1) | 0.046 | 0 (0) | 0 (0) | 0.001 |
| Operation type | ||||||
| Laparoscopy | 644 (89.6) | 1481 (80.0) | 0.27 | 643 (89.7) | 1271 (90.1) | 0.016 |
| Robotic | 1 (0.1) | 188 (10.2) | 0.465 | 1 (0.1) | 2 (0.1) | 0.001 |
| Laparotomy | 74 (10.3) | 183 (9.9) | 0.012 | 73 (10.2) | 137 (9.7) | 0.016 |
| T staging | ||||||
| T0 | 16 (2.2) | 40 (2.2) | 15 (2.1) | 26 (1.8) | ||
| T1 | 179 (24.9) | 483 (26.1) | 0.029 | 179 (25.0) | 362 (25.7) | 0.018 |
| T2 | 238 (33.1) | 566 (30.1) | 0.055 | 238 (33.2) | 465 (33.0) | 0.005 |
| T3 | 254 (35.3) | 629 (34.0) | 0.029 | 252 (35.3) | 496 (35.2) | 0.003 |
| T4 | 32 (4.5) | 134 (7.2) | 0.119 | 32 (4.5) | 61 (4.3) | 0.007 |
| Tumor location | ||||||
| Right | 218 (30.3) | 504 (27.2) | 0.069 | 217 (30.3) | 445 (31.6) | 0.028 |
| Left | 497 (69.1) | 1327 (71.7) | 0.054 | 496 (69.2) | 957 (67.9) | 0.029 |
| Rectum | 4 (0.6) | 21 (1.1) | 0.073 | 4 (0.6) | 8 (0.6) | 0.01 |
| Lymphatic invasion | 207 (28.8) | 537 (29.0) | 0.004 | 206 (28.7) | 407 (28.9) | 0.003 |
| Perineural invasion | 311 (43.3) | 811 (43.8) | 0.01 | 310 (43.2) | 601 (42.6) | 0.013 |
| Vascular invasion | 58 (8.1) | 137 (7.4) | 0.025 | 58 (8.1) | 99 (7.0) | 0.041 |
| Anaesthesia time, min | 173 [149, 204] | 176 [143, 226] | 0.115 | 173 [149, 203] | 169.5 [141, 213] | 0.014 |
| Transfusion | 9 (1.3) | 43 (2.3) | 0.081 | 9 (1.3) | 18 (1.3) | 0.002 |
| Adjuvant therapy | 445 (61.9) | 1131 (61.1) | 0.038 | 443 (61.8) | 840 (59.6) | 0.046 |
Values are expressed as mean (SD), median [IQR] or number (%). History of surgery included abdominal surgeries and cesarean section. Charlson Comorbidity Index (CCI) is a method to estimate 10-year survival in patients with multiple comorbidities. Heavy drinking, consuming 15 drinks or more per week for men or eight drinks or more per week for women as defined by the Centers for Disease Control and Prevention. Eastern Cooperative Oncology Group (ECOG) performance status: 0 Fully active; no performance restrictions, 1 Strenuous physical activity restricted; fully ambulatory and able to carry out light work, 2 Capable of all self-care but unable to carry out any work activities. Up and about >50% of waking hours, 3 Capable of only limited self-care; confined to bed or chair >50% of waking hours, 4 Completely disabled; cannot carry out any self-care; totally confined to bed or chair. ASA, American Society of Anesthesiologists; BMI, body mass index; CAD, coronary artery disease; CCI, Charlson Comorbidity Index, CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; ECOG, Eastern Cooperative Oncology Group; NLR, Neutrophil/Lymphocyte ratio.