Table 1.
Demographic, surgical and baseline characteristics of patients by early haemodynamic responses
|
CI early response⁎ |
MAP early response† |
||||||
|---|---|---|---|---|---|---|---|
| Whole cohort (n = 20) | CI non-responders (n = 15) | CI responders (n = 5) | P | MAP non-responders (n = 9) | MAP responders (n = 11) | P | |
| Age (years), median (IQR) | 67 (64.2–75.8) | 69 (60.5–78.5) | 67 (66–67) | 0.97 | 70 (66–79) | 66 (60.5–71) | 0.20 |
| Gender (female) | 4 (20%) | 2 (13%) | 2 (40%) | 0.25 | 2 (22%) | 2 (18%) | >0.99 |
| Body surface area (m2), median (IQR) | 2 (1.8–2.1) | 2 (1.7–2.2) | 1.9 (1.9–2) | 0.60 | 1.9 (1.7–2) | 2.1 (1.9–2.2) | 0.12 |
| Type of surgery | >0.99 | 0.84 | |||||
| CABG | 12 (60%) | 9 (60%) | 3 (60%) | 5 (56%) | 7 (64%) | ||
| Valves | 5 (25%) | 4 (27%) | 1 (20%) | 2 (22%) | 3 (27%) | ||
| CABG + valves | 3 (15%) | 2 (13%) | 1 (20%) | 2 (22%) | 1 (9%) | ||
| Post-bypass LV function | >0.99 | 0.11 | |||||
| Normal | 11 (55%) | 8 (53%) | 3 (60%) | 7 (78%) | 4 (36%) | ||
| Dysfunction | 6 (30%) | 5 (33%) | 1 (20%) | 1 (11%) | 5 (45%) | ||
| Post-bypass RV function | >0.99 | >0.99 | |||||
| Normal | 16 (80%) | 12 (80%) | 4 (80%) | 8 (89%) | 8 (73%) | ||
| Dysfunction | 1 (5%) | 1 (7%) | 0 (0%) | 0 (0%) | 1 (9%) | ||
| Bypass duration (min), median (IQR) | 114.5 (89.5–144.8) | 116 (88–137.5) | 113 (96–180) | 0.63 | 113 (85–121) | 116 (93.5–173.5) | 0.32 |
| Heart rhythm | 0.50 | 0.81 | |||||
| Paced | 11 (55%) | 7 (47%) | 4 (80%) | 5 (56%) | 6 (55%) | ||
| Sinus rhythm | 8 (40%) | 7 (47%) | 1 (20%) | 3 (33%) | 5 (45%) | ||
| Atrial fibrillation | 1 (5%) | 1 (7%) | 0 (0%) | 1 (11%) | 0 (0%) | ||
| Cl measuring technique | 0.06 | 0.20 | |||||
| Discontinuous | 12 (60%) | 7 (47%) | 5 (100%) | 7 (78%) | 5 (45%) | ||
| Semi-continuous | 8 (40%) | 8 (53%) | 0 (0%) | 2 (22%) | 6 (55%) | ||
| Mechanical ventilator setting, median (IQR) | |||||||
| Tidal volume (mL/IBW) | 7.9 (6.8–8.6) | 8 (6.9–8.4) | 7.5 (6.8–8.5) | >0.99 | 8 (5.9–8.3) | 7.8 (7.2–8.7) | 0.41 |
| Peak pressure (cmH20) | 19 (16.5–21) | 19 (17–21) | 18 (15–21) | 0.73 | 19 (17–21) | 19 (16–20.5) | >0.99 |
| PEEP | 5 (5-5) | 5 (5–5) | 5 (5–5) | 0.90 | 5 (5–5) | 5 (5–5) | >0.99 |
| Fio2 | 0.5 (0.3–0.6) | 0.5 (0.3–0.6) | 0.5 (0.3–0.5) | 0.69 | 5 (5–5) | 0.6 (0.4–0.8) | 0.06 |
| Biochemistry findings, median (IQR) | |||||||
| Lactate (mmol/L) | 1 (0.9–1.4) | 1.1 (0.9–1.4) | 0.9 (0.8–1) | 0.16 | 1.1 (0.9–1.5) | 1 (0.9–1.4) | 0.65 |
| Active external warming | |||||||
| Use of external warming | 8 (40%) | 6 (40%) | 2 (40%) | > 0.99 | 3 (33%) | 5 (45%) | > 0.99 |
| Haemodynamic support | |||||||
| Vasopressors | 7 (35%) | 6 (40%) | 1 (20%) | 0.61 | 4 (44%) | 3 (27%) | 0.64 |
| Inotropes | 2 (13%) | 0 (0%) | > 0.99 | 1 (11%) | 1 (9%) | > 0.99 | |
| Number of fluid boluses received before study | |||||||
| 0 | 18 (90% | 14 (93%) | 4 (80%) | 9 (100%) | 9 (82%) | ||
| 1 | 1 (5%) | 0 (0%) | 1 (20%) | 0 (%) | 1 (9%) | ||
| ≥ 2 | 1 (5%) | 1 (7%) | 0 (0%) | 0 (%) | 1 (9%) | ||
CABG = coronary artery bypass graft; CI = cardiac index; Fio2 = fraction of inspired oxygen; IBW = ideal body weight; IQR = interquartile range; LV = left ventricle; MAP = mean arterial pressure; PEEP = positive end-expiratory pressure; RV = right ventricle.
Early CI response to fluid bolus therapy (FBT) was verified when CI increased by ≥ 15% above baseline immediately after the end of the FBT infusion.
Early MAP response to FBT was verified when MAP increased by ≥ 10% above baseline immediately after the end of the FBT infusion. Dissipation of CI response to FBT was verified when CI was no greater than 5% above baseline for at least 2 consecutive minutes. Dissipation of MAP response to FBT was verified when MAP was no greater than 3 mmHg above baseline for at least 2 consecutive minutes.