Table 1.
Patients’ demographic and clinical characteristics in capillary refill time responders and non-responders to volume expansion
| Characteristics | All (n = 34) | CRT responders (n = 15) | CRT non-responders (n = 19) | p value |
|---|---|---|---|---|
| Anthropometry | ||||
| Age, years | 62 [54, 69] | 59 [46, 71] | 64 [57, 68] | 0.435 |
| Sex, male/female, n | 25/9 | 13/2 | 12/7 | |
| Weight, kg | 71 [62, 80] | 75 [67, 81] | 70 [61, 78] | 0.289 |
| Severity scores | ||||
| SOFA | 8 [6, 11] | 9 [7, 12] | 8 [6, 10] | 0.485 |
| SAPS2 | 42 [33, 51] | 44 [33, 56] | 41 [34, 48] | 0.266 |
| Circulatory failure aetiology | ||||
| Sepsis | 11 | 3 | 8 | 0.271 |
| SIRS | 15 | 8 | 7 | 0.489 |
| Cardiogenic shock | 8 | 4 | 4 | 1.0 |
| Metabolic and peripheral perfusion | ||||
| Mottling score | 1 [0, 2] | 1 [0, 2] | 1 [0, 1] | 0.702 |
| Capillary refill time, s | 2.9 [2.4, 3.7] | 3.6 [2.8, 6] | 2.6 [2.3, 3.3] | 0.021 |
| PCO2gap, kPa | 1.1 [0.8, 1.7] | 1.4 [1.1, 1.8] | 0.8 [0.7, 1.1] | 0.007 |
| Oxygen delivery, mL min−1 m−2 | 337 [272, 417] | 313 [253, 361] | 355 [309, 440] | 0.228 |
| Oxygen uptake, mL min−1 m−2 | 101 [84, 116] | 97 [64, 119] | 103 [88, 109] | 0.383 |
| Modified RQ, mmHg mL−1 | 2.6 [2.0, 5.4] | 3.5 [2.4, 6.8] | 2.6 [2.0, 4.0] | 0.118 |
| Oxygen extraction ratio, % | 30 [25, 35] | 35 [26, 40] | 28 [23, 30] | 0.051 |
| Lactate, mmol L−1 | 2.0 [1.2, 3.8] | 2.0 [1.4, 3.8] | 2.0 [1.1, 3.5] | 0.578 |
| Thermodilution | ||||
| Cardiac index, L min−1 m−2 | 2.6 [2.1, 3.1] | 2.3 [2.0, 3.0] | 2.6 [2.4, 3.2] | 0.499 |
| Global end-diastolic volume index, mL m−2 | 710 [549, 827] | 667 [506, 826] | 726 [606, 823] | 0.492 |
| Extravascular lung water index, mL kg−1 | 9.1 [7.0, 12.0] | 9.2 [6.5, 12.5] | 9.1 [7.2, 11.5] | 0.931 |
| Cardiac function index | 3.6 [2.9, 4.3] | 3.6 [2.8, 4.3] | 3.6 [3.1, 4.3] | 0.718 |
| Pulmonary vascular permeability index | 1.8 [1.4, 2.6] | 1.8 [1.5, 2.7] | 1.7 [1.3, 2.5] | 0.772 |
| Stroke volume variation, % | 13 [9, 17] | 14 [11, 17] | 13 [8, 17] | 0.676 |
| Haemodynamics | ||||
| Heart rate, cycle/min | 95 [75, 110] | 96 [73, 104] | 93 [78, 112] | 0.395 |
| Mean arterial pressure, mmHg | 68 [61, 72] | 70 [62, 75] | 67 [61, 71] | 0.357 |
| Systolic arterial pressure, mmHg | 102 [91, 118] | 97 [90, 116] | 104 [94, 116] | 0.795 |
| Diastolic arterial pressure, mmHg | 51 [43, 57] | 52 [46, 57] | 51 [41, 56] | 0.615 |
| Pulse pressure, mmHg | 53 [40, 65] | 49 [36, 65] | 53 [41, 64] | 0.532 |
| EtCO2, mmHg | 36 [32, 45] | 34 [32, 44] | 37 [31, 46] | 0.737 |
| Central venous pressure, mmHg | 7 [4, 11] | 8 [7, 11] | 6 [3, 9] | 0.186 |
| Drugs | ||||
| Norepinephrine, μg kg−1 min−1 | 0.22 [0.10, 0.51] | 0.17 [0.08, 0.76] | 0.23 [0.11, 0.49] | 0.798 |
| Dobutamine, μg kg−1 min−1 | 4 [0, 6] | 4 [0, 5] | 4 [0, 7] | 0.531 |
| Epinephrine, μg kg−1 min−1 | 0.00 [0.00, 0.04] | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.05] | 0.472 |
| Ventilation | ||||
| Tidal volume, mL kg−1 of ideal body weight | 6 [6, 7] | 6 [6, 7] | 6 [6, 8] | 0.702 |
| Respiratory rate, cycles min−1 | 24 [20, 27] | 24 [23, 27] | 22 [17, 29] | 0.357 |
| Positive end-expiratory pressure, cmH2O | 5 [5, 6] | 6 [5, 6] | 5 [5 6] | 0.937 |
| FiO2, % | 40 [30, 60] | 40 [36, 51] | 40 [30, 60] | 0.607 |
| Driving pressure, cmH2O | 12 [9, 15] | 12 [10, 14] | 12 [9, 15] | 0.806 |
Values are median [percentile 25–75] or number. Wilcoxon test and Fisher’s exact test were used to calculate p value. CRT responders are defined as patients showing a decrease of at least 25% of the capillary refill time after volume expansion
CRT capillary refill time, EtCO2 end-tidal carbon dioxide, FiO2 fraction of inspired dioxygen, Modified RQ modified respiratory quotient defined as PCO2gap/difference in arterio-venous content in oxygen, PCO2gap veno-arterial difference in carbon dioxide partial pressure, SAPS2 Simplified Acute Physiology Score, SIRS systemic inflammatory response syndrome, SOFA Sequential Organ Failure Assessment