Table 1.
Baseline characteristics.
| Characteristic | All Patients (n = 69) | Optimal PEEP Group (n = 44) | Standard PEEP Group (n = 25) | P Value |
|---|---|---|---|---|
| Age (yr) | 46.6 | 43.3 | 52.3 | 0.004 |
| Ethnicity (n, %) | Asian (3, 4.35), Black (3, 4.35), Hispanic (24, 34.8), Native American (4, 5.80), Native Pacific Islander (1, 1.45), White (27, 39.1), Declined (7, 10.1) | Asian (3, 6.81), Black (2, 4.55), Hispanic (11, 25.0), Native American (2, 4.55), White (19, 43.2), Declined (7, 15.9) | Black (1, 4.00), Hispanic (13, 52.0), Native American (2, 4.55), Native Pacific Islander (1, 4.00), White (8, 32.0) | n/a |
| Male, n (%) | 48 (69.6) | 28 (63.6) | 20 (80.0) | 0.184 |
| Body Mass Index, median (kg/m2) | 39.5 | 42.5 | 34.2 | 0.011 |
| Murray Score, median | 3.75 | 3.77 | 3.71 | 0.373 |
| Comorbidities, n (%) | ||||
| Immunocompromised | 5 (7.25) | 3 (6.82) | 2 (8.00) | >0.999 |
| Coronary artery disease | 0 (0) | 1 (2.27) | 0 (0) | >0.999 |
| Hypertension | 15 (21.7) | 9 (20.5) | 6 (24.0) | 0.767 |
| Diabetes Mellitus | 20 (29.0) | 13 (29.5) | 7 (28.0) | >0.999 |
| Chronic Kidney Disease | 2 (2.90) | 2 (4.55) | 0 (0) | 0.531 |
| Pre-ECMO support | ||||
| HFNC, n (%) | 56 (81.2) | 35 (79.5) | 21 (84.0) | 0.756 |
| NIPPV, n (%) | 28 (40.6) | 19 (43.2) | 9 (36.0) | 0.617 |
| Pre-ECMO ventilator days | 3.38 | 3.93 | 2.40 | 0.165 |
| Pre-ECMO proning, n (%) | 64 (92.8) | 42 (95.5) | 22 (88.0) | 0.344 |
| Paralytics, n (%) | 65 (94.2) | 42 (95.5) | 23 (92.0) | 0.617 |
| Vasopressor, n (%) | 40 (58.0) | 26 (59.1) | 14 (56.0) | 0.806 |
| Ventilator mode (n, %) | VC (54, 78.3), APRV (7, 10.1), PC (3, 4.35), VDR (1, 1.45), Undocumented (4, 5.80) | VC (36, 81.8), APRV (3, 6.82), PC (2, 4.55), VDR (0,0), Undocumented (3, 6.82) | VC (18, 72.0), APRV (4, 16.0), PC (1, 4.00), VDR (1, 4.00), Undocumented (1, 4.00) | n/a |
| ABG prior to cannulation | ||||
| pH | 7.26 | 7.26 | 7.26 | 0.423 |
| pCO2 (mmHg) | 68.4 | 70.1 | 65.2 | 0.240 |
| pO2 (mm Hg) | 73.9 | 68.7 | 83.1 | 0.160 |
| Bicarbonate (mEq/L) | 29.6 | 30.4 | 28.1 | 0.210 |
ECMO = extracorporeal membrane oxygenation, HFNC = high-flow nasal cannula, NIPPV = noninvasive positive pressure ventilation, ABG = arterial blood gas, VC = volume control, APRV = airway pressure release ventilation, PC = pressure control, VDR = volumeric diffusive respirator. Bold values are those with a significant p value.