Table 2.
Hemodynamic, respiratory and gas exchange variables.
| Variable | Successful weaning (n = 89) | Failure to wean (n = 12) | p-value |
| Hemodynamic | |||
| HR-1 (beats/min)*) | 96 (92-100) | 93 (80-105) | 0.435 |
| HR-2 (beats/min)*) | 103 (101-106) | 96 (89-103) | 0.087 |
| MAP-1 (mmHg)*) | 92 (89-96) | 93 (83-102) | 0.983 |
| MAP-2 (mmHg)*) | 89 (87-92) | 85 (78-93) | 0.239 |
| PAOP-1 (mmHg)*)$ | 14 (13-15) | 14 (10-17) | 0.855 |
| PAOP-2 (mmHg)*)$ | 10 (9-12) | 12 (9-15) | 0.440 |
| CVP-1 (mmHg)*) | 10 (9-11) | 10 (8-12) | 0.883 |
| CVP-2 (mmHg)** | 9 (5-10) | 11 (9-15) | 0.023 |
| PCP-1 (%)*)$ | 14 (13-15) | 14 (10-17) | 0.855 |
| PCP-2 (%)*)$ | 10 (9-12) | 12 (9-15) | 0.440 |
| ScvO2-1 (%)** | 77 (70-81) | 77 (69-77) | 0.781 |
| ScvO2-2 (%)*) | 69 (68-71) | 62 (58-65) | 0.002 |
| CI-1 (L/min/m2)$*) | 3.17 (2.83-3.50) | 2.75 (2.31-3.20) | 0.361 |
| CI-2 (L/min/m2)$*) | 3.33 (3.08-3.58) | 2.76 (2.21-3.30) | 0.068 |
| Lactate-1 (mmol/L)** | 4.0 (2.9-6.1) | 2.3 (1.3-5.0) | 0.313 |
| Lactate-2 (mmol/L)** | 2.9 (1.8-4.6) | 1.9 (1.4-3.6) | 0.296 |
| Hb-1 (g/dL)** | 10.8 (9.8-11.8) | 9.8 (9.2-11.7) | 0.154 |
| Hb-2 (g/dL)** | 10.6 (9.6-11.8) | 10 (8.9-10.2) | 0.084 |
| Dobutamine-1** | 10 (8-17) | 14 (9-18) | 0.519 |
| Dobutamine-2** | 12 (9-16) | 15 (11-18) | 0.044 |
| Respiratory | |||
| PaO2-1 (mmHg)*) | 145 (136-154) | 142 (113-171) | 0.754 |
| PaO2-2 (mmHg)** | 107 (90-143) | 117 (88-152) | 0.550 |
| PaCO2-1 (mmHg)** | 40 (36-44) | 39 (36-45) | 0.806 |
| PaCO2-2 (mmHg)** | 37 (33-40) | 37 (34-41) | 0.303 |
| pH-1** | 7.3 (7.3-7.4) | 7.4 (7.3-7.4) | 0.313 |
| pH-2** | 7.4 (7.3-7.4) | 7.4 (7.3-7.4) | 0.232 |
| Tobin-2** | 36 (26-45) | 45 (29-83) | 0.098 |
| SC-1 (mL/cmH2O)** | 38 (32-49) | 39 (33-51) | 0.889 |
| Natriopeptides (ng/L) | |||
| BNP-1** | 73 (28-127) | 214 (65-487) | 0.020 |
| BNP-2** | 140 (80-226) | 416 (311-561) | <0.001 |
*mean (95% Confidence Interval), t-test, **median (Interquartile Range), Mann-Whitney test. $evaluated in the 44 patients who had a pulmonary artery catheter inserted – 36 in the successful weaning group and 8 in the failure to wean group. 1- at intensive care unit admission; 2- at the end of the spontaneous breathing test; HR: heart rate; MAP: mean arterial pressure; PAOP: pulmonary artery occlusion pressure; CVP: central venous pressure; ScvO2: central venous oxygen saturation; Hb: hemoglobin concentration; SC = Static compliance; CI: cardiac index.