Table 1 Perioperative characteristics of the patients
Variables | Phase 1 (n=25) | Phase 2 | ||
|---|---|---|---|---|
Traditional ventilation (n=32) | Protective ventilation (n=32) | P (within phase 2) | ||
Age (years) | 68.6±7.6 | 69.9±6.8 | 70.3±6.4 | 0.441 |
 Range | 60–84 | 60–83 | 60–82 |  |
Weight (kg) | 67.8±9.0 | 64.2±9.1 | 63.1±9.1 | 0.242 |
BMI (kg/m2) | 23.5±2.7 | 22.6±3.1 | 22.5±2.6 | 0.274 |
 Range | 17.0–28.7 | 17.1–29.9 | 17.0–28.3 |  |
PBW (kg) | 65.2±4.5 | 65.1±5.0 | 62.8±5.6 | 0.233 |
ASA grade | ||||
 II | 24 (96%) | 30 (93.8%) | 30 (93.8%) | 0.918 |
 III | 1 (4%) | 2 (6.3%) | 2 (6.3%) | 0.918 |
LVEF (%) | 66.3±5.4 | 68.5±7.3 | 65.6±7.6 | 0.208 |
Hypertension | 17 (68%) | 18 (56.3%) | 15 (46.9%) | 0.280 |
Diabetes mellitus | 7 (28%) | 5 (15.6%) | 4 (12.5%) | 0.309 |
Coronary disease | 0 | 2 (6.3%) | 1 (3.1%) | 0.429 |
Cerebral infarction | 1 (4%) | 2 (6.3%) | 1 (3.1%) | 0.828 |
Smoking history | Â | Â | Â | 0.458 |
 Never | 14 (56.0%) | 23 (71.9%) | 21 (65.6%) |  |
 Former | 4 (16.0%) | 3 (9.4%) | 4 (12.5%) |  |
 Current | 7 (28.0%) | 6 (18.7%) | 7 (21.9%) |  |
Operation time (min) | 184.3±64.4 | 183.2±64.7 | 175.4±52.6 | 0.843 |
Postoperative hospital stay (days) |  | 8.3±3.9 | 9.3±3.7 | 0.494 |
Estimated blood loss (ml) | 138 (30–600) | 89 (50–300) | 100 (50–250) | 0.249 |
Fluids (ml) | 1790 (1200–3250) | 1616 (1200–2800) | 1605 (1100–2250) | 0.314 |
Need for vaspressors (n)a | 10 (40%) | 12 (37.5%) | 10 (31.3%) | 0.772 |
Ephedrine total dose (mg)b | 7.3±2.6 | 6.6±1.9 | 7.3±2.6 | 0.809 |
Phenylephrine total dose (ug)c | 83.3±57.7 | 87.5±47.9 | 75.0±50.0 | 0.998 |
Duration of CO2 pneumoperitoneum (min) | 135±58 | 143±56 | 129±43 | 0.686 |