Table 1. Patient characteristics.
| Total | Aortic Surgery | Valve surgery | OPCAB | p-value | |
| Number of patients | 87 | 21 | 33 | 33 | |
| Baseline characteristics | ANOVA | ||||
| Age (year) | 64.0±12.0 | 60±13 | 63±14 | 68±8# | 0.04* |
| Body weight (kg) | 61.4±11.7 | 63.9±10.7 | 59.1±13.1 | 62.2±10.6 | 0.30 |
| White blood cell count (cells/mm3) | 5918±1549 | 6015±1470 | 5779±1532 | 5992±1648 | 0.81 |
| Hemoglobin (g/dL) | 12.5±1.6 | 12.3±1.3 | 12.5±1.3 | 12.8±1.9 | 0.53 |
| Platelet count (104/mm3) | 20.2±6.3 | 19.2±7.0 | 19.6±5.5 | 21.4±6.4 | 0.36 |
| Total protein (g/dL) | 7.1±0.5 | 7.0±0.5 | 7.0±0.5 | 7.2±0.6 | 0.47 |
| Albumin (g/dL) | 4.1±0.5 | 4.1±0.4 | 4.2±0.4 | 4.0±0.4 | 0.25 |
| BUN (mg/dL) | 19.8±10.3 | 17.6±7.0 | 19.2±6.9 | 21.8±14.0 | 0.32 |
| Creatinine (mg/dL) | 1.1±0.7 | 1.2±0.9 | 1.0±0.3 | 1.2±0.8 | 0.37 |
| Mean Blood Pressure (mm Hg) | 91±13 | 93±15 | 85±11$$ | 95±11 | 0.004* |
| Heart rate (beats/min) | 71±12 | 70±11 | 72±13 | 70±13 | 0.71 |
| PaO2/FIO2 after the anesthetic induction | 412±112 | 394±116 | 427±110 | 408±112 | 0.56 |
| Chi square test | |||||
| Male/Female, (Male %) | 64/23 (74%) | 16/5 (76%) | 21/12 (64%) | 27/6 (82%) | 0.68 |
| Diabetes Mellitus +/−, (Morbidity %) | 27/60 (31%) | 1/20 (4.8%) | 9/24 (27%) | 18/15 (56%) | 0.006** |
| Hemodialysis +/−, (Morbidity %) | 2/85 (2.3%) | 1/20 (4.8%) | 1/32 (3.0%) | 0/33 (0%) | 0.50 |
| History of smoking +/−, (Morbidity %) | 51/36 (59%) | 16/5 (76%) | 20/13 (61%) | 16/17 (48%) | 0.44 |
| Surgical duration | ANOVA | ||||
| Duration of operation (min) | 400±130 | 515±166 | 384±80## | 343±99## | <0.0001 |
| Mann-Whitney U test | |||||
| Duration of cardiopulmonary bypass (min) | 213±109 | 197±52 | 0.33 | ||
| Intraoperative mechanical ventilation | ANOVA | ||||
| Tidal volume (mL/kg of PBW§1) | 9.3±1.4 | 9.3±1.3 | 9.5±1.4 | 9.1±1.3 | 0.52 |
| Peak inspiratory pressure (cmH2O) | 20±5 | 21±5 | 20±5 | 18±5 | 0.12 |
| PEEP level (cmH2O) | 5±2 | 6±2$$ | 5±1 | 5±1 | 0.006** |
| Intraoperative transfusion | Kruskal-Wallis test | ||||
| Red cell (units§2) §4 | 4 (0–8) | 0 (0–4) | 0 (0–2)# | 0.0097** | |
| Fresh frozen plasma (units§2) §4 | 6 (0–12) | 0 (0–6)# | 0 (0–0)## | 0.001** | |
| Platelet(units§3)§4 | 20 (0–20) | 0 (0–0)## | 0 (0–0)## | <0.0001** |
OPCAB: off-pump coronary artery bypass grafting.
#
p<0.05 vs. aortic surgery group.
*
p<0.05.
$$
p<0.01 vs. OPCAB group.
**
p<0.01.
§1
PBW: predicted body weight; male PBW (kg) = 50+0.91(height (cm) –152.4), and female PBW (kg) = 45.5+0.91(height (cm) –152.4).
§2
1 unit of packed red cells or fresh frozen plasma is derived from 200 mL of donated blood.
§3
1 unit of packed platelet concentrate contains 2×1010 platelets.
§4
Data are shown as median with interquartile range.