Table 2.
Univariate analysis.
| Variables | Weaning failure group (n = 61) | Weaning success group (n = 165) | Statistical value | p |
|---|---|---|---|---|
| Sex (male/female) | 37/24 | 104/61 | χ 2 = 0.107 | 0.744 |
| Age (years, M [Q1, Q3]) | 53.5 (35, 61.3) | 51.0 (36, 61.5) | Z = −0.241 | 0.810 |
| Tibetan (n [%]) | 53 (86.9) | 140 (84.8) | χ 2 = 0.148 | 0.700 |
| BMI (kg/m2, M [Q1, Q3]) | 23.44 (20.76, 26.12) | 22.86 (20.76, 25.37) | Z = −0.322 | 0.747 |
| Altitude of residence (m, M [Q1, Q3]) | 3820 (3600, 4200) | 3900 (3600, 4300) | Z = −0.317 | 0.751 |
| ICU assessment and past history | ||||
| Craniocerebral diseases (n [%]) | 38 (62.3) | 99 (60) | χ 2 = 0.098 | 0.754 |
| APACHE II score (M [Q1, Q3]) | 16 (12, 19) | 14 (10, 18) | Z = −2.876 | 0.004∗ |
| Stroke (n [%]) | 1 (1.6) | 1 (0.6) | Z = 0.000 | 0.998 |
| Heart disease (n [%]) | 5 (8.2) | 9 (5.5) | χ 2 = 0.201 | 0.654 |
| Respiratory disease (n [%]) | 1 (1.6) | 7 (4.2) | χ 2 = 0.286 | 0.593 |
| Hypertension (n [%]) | 32 (52.5) | 53 (32.1) | χ 2 = 7.850 | 0.005∗ |
| Diabetes (n [%]) | 4 (6.6) | 9 (5.5) | χ 2 = 0.100 | 0.752 |
| Liver insufficiency (n [%]) | 3 (4.9) | 8 (4.8) | χ 2 = 0.000 | 0.983 |
| Smoking (n [%]) | 12 (19.7) | 37 (22.4) | χ 2 = 0.199 | 0.656 |
| Laboratory indicators | ||||
| Leukocyte (× 109/L, M [Q1, Q3]) | 11.00 (8.55, 13.5) | 9.50 (7.80, 13.20) | Z = −2.045 | 0.041∗ |
| Platelets (× 109/L, M [Q1, Q3]) | 178 (99, 255) | 183 (132, 274) | Z = −0.995 | 0.320 |
| Hemoglobin (g/L, M [Q1, Q3]) | 114 (88, 148) | 109 (89, 126) | Z = −0.779 | 0.436 |
| ALT (U/L, M [Q1, Q3]) | 40.0 (20.0, 75.3) | 35 (19.5, 72.3) | Z = −0.367 | 0.714 |
| Total bilirubin (mmol/L, M [Q1, Q3]) | 20.2 (10.2, 40.0) | 15.0 (9.5, 24.2) | Z = −1.799 | 0.072∗ |
| Creatinine (umol/L, M [Q1, Q3]) | 56.5 (33.8, 72.8) | 52.0 (39.5, 68.0) | Z = −0.470 | 0.638 |
| C-reactive protein (ng/mL, M [Q1, Q3]) | 100.0 (61.1, 137.7) | 58.4 (30.8, 122.6) | Z = −3.033 | 0.002∗ |
| Serum albumin (g/L, M [Q1, Q3]) | 31.5 (29.6, 34.2) | 33.5 (30.6, 36.8) | Z = −2.961 | 0.003∗ |
| Hypersensitive troponin I (ng/mL, M [Q1, Q3]) | 0.0050 (0.003, 0.0165) | 0.0040 (0.0010, 0.0150) | Z = −1.696 | 0.090∗ |
| P/F ratio (mmhg, M [Q1, Q3]) | 224 (183, 251) | 224 (218, 342) | Z = −4.635 | < 0.001∗ |
| PaCO2 (mmhg, M [Q1, Q3]) | 33 (29, 37) | 35 (30, 38) | Z = −1.395 | 0.163 |
| Lactic acid (mmol/L, M [Q1, Q3]) | 1.1 (0.8, 1.5) | 0.9 (0.7, 1.2) | Z = −1.937 | 0.053∗ |
| Preweaning conditions | ||||
| SOFA score (M [Q1, Q3]) | 4 (2, 6) | 2 (0, 3) | Z = −6.050 | < 0.001∗ |
| Tidal volume (ml, M [Q1, Q3]) | 390 (320, 432) | 520 (455, 600) | Z = −7.447 | < 0.001∗ |
| Respiratory rate (breath/min, M [Q1, Q3]) | 24 (22, 27) | 18 (15, 21) | Z = −7.528 | < 0.001∗ |
| Vasoactive drugs (n [%]) | 43 (70.5) | 78 (47.3) | χ 2 = 9.652 | 0.002∗ |
| Fluid balance in 24 h (mL/L, M [Q1, Q3]) | −16 (−1031, 505) | −596 (−1061, −321) | Z = −3.165 | 0.002∗ |
Note: ALT, alanine aminotransferase, P/F ratio, PaO2/FiO2.
Abbreviations: APACHE II, Acute Physiology and Chronic Health Evaluation II; BMI, body mass index; SOFA, sequential organ failure assessment.
∗p < 0.1.