Table 3.
Comparison of matched (by GenMatch) and unmatched ECMO-treated patients
| Unmatched (n = 34) | Matched (n = 209) | p-value | |
|---|---|---|---|
| Demographics | |||
| Age (years) | 37 [34, 45.75] | 46 [40, 53] | < 0.001 |
| Male sex | 23 (67.6) | 144 (68.9) | 1 |
| Body mass index (kg/m2) | 31.77 [26.84, 34.05] | 31.64 [28.37, 35.92] | 0.559 |
| Clinical frailty scale | 2 [1, 2] | 2 [1, 2] | 0.013 |
| Immuno-compromised | 1 (2.9) | 4 (1.9) | 1 |
| Pre-referral admission characteristics | |||
| Hospital duration prior to IMV (days) | 5 [2.76, 6.49] | 4.11 [2, 7.27] | 0.52 |
| Duration of IMV (days) | 1.5 [1, 3] | 2 [1, 5] | 0.021 |
| Cardiac arrest | 0 (0) | 5 (2.4) | 0.795 |
| Therapeutic interventions | |||
| Non-invasive ventilation | 22 (64.7) | 146 (69.9) | 0.687 |
| Corticosteroids | 14 (41.2) | 129 (61.7) | 0.038 |
| Interleukin-6 inhibitor | 1 (2.9) | 15 (7.2) | 0.582 |
| Prone position trial | 30 (88.2) | 163 (78) | 0.254 |
| Chest drain(s) for pneumothorax | 3 (8.8) | 11 (5.3) | 0.668 |
| Renal replacement therapy | 0 (0) | 6 (2.9) | 0.686 |
| Anticoagulation | 0.303 | ||
| Contraindicated | 0 (0) | 0 (0) | |
| Prophylactic | 28 (82.4) | 151 (72.2) | |
| Therapeutic | 6 (17.6) | 58 (27.8) | |
| Respiratory parameters at time of referral | |||
| P/F ratio (mmHg) | 62.62 [57.36, 71.63] | 72.53 [63, 85.61] | < 0.001 |
| Static compliance (mL/cmH2O) | 31.73 [25.18, 33.21] | 29.23 [21.58, 35] | 0.404 |
| Driving pressure (cmH2O) | 16 [14.18, 20] | 16 [13, 20] | 0.765 |
| Plateau pressure (cmH2O) | 28.5 [25.25, 30] | 29 [25, 32] | 0.414 |
| Vt/PBW (mL/kg) | 6.92 [6.56, 7.99] | 6.73 [6.1, 7.85] | 0.266 |
| Positive end expiratory pressure (cmH2O) | 11.96 [10, 14] | 12 [10, 14] | 0.213 |
| Minute ventilation (L/min) | 10.38 [9, 11.71] | 9.88 [8.1, 11.39] | 0.255 |
| Arterial blood gas parameters at time of referral | |||
| pH | 7.31 [7.25, 7.36] | 7.31 [7.24, 7.38] | 0.69 |
| pCO2 (mmHg) | 54.25 [47.46, 71.46] | 58.5 [50.4, 68.25] | 0.475 |
| Base excess (mmol/L) | 2.77 [1.39, 5.18] | 3.57 [1.7, 6.4] | 0.166 |
| Lactate (mmol/L) | 1.32 [1.07, 2.1] | 1.3 [1.1, 1.77] | 0.406 |
| Laboratory parameters at time of referral | |||
| White cell count (109/L) | 12 [9.74, 15.23] | 12 [9.7, 14.7] | 0.829 |
| Platelet count (109/L) | 285.78 [266.5, 363.49] | 283.91 [253, 331.59] | 0.515 |
| Haemoglobin (g/L) | 109.5 [100.25, 125.75] | 117 [101, 127] | 0.406 |
| C-reactive protein (mg/L) | 240.9 [152, 332.75] | 187 [101, 296.61] | 0.133 |
| Severity and risk scores | |||
| RESP score | 5 [5, 7] | 5 [4, 6] | 0.011 |
| SOFA score | 6.61 [4.08, 7] | 5 [4, 7.04] | 0.205 |
| Outcomes | |||
| Died | 6 (17.6) | 54 (25.8) | 0.416 |
Values are expressed as median value [95% CI] or as n (%); IMV invasive mechanical ventilation, P/F ratio partial pressure of arterial oxygen to fraction of inspired oxygen ratio, Vt tidal volume, PBW predicted body weight, RESP respiratory ECMO survival prediction, SOFA sequential organ failure assessment