Table 2. The general characteristics of 67 critical COVID-19 patients by CRRT.
| Variable | Total | CRRT (n=38) | Non-CRRT (n=29) | t/χ2/Z | P | |
| Age (years) | 67.6±12.3 | 66.9±11.8 | 68.6±13.0 | 0.552a | 0.583 | |
| Sex | ||||||
| Female | 16 | 7(18.4) | 9(31.0) | 1.440c2 | 0.230 | |
| Male | 51 | 31(81.6) | 20(69.0) | |||
| Smoking | 8 | 6(21.4) | 2(8.7) | 0.269f | ||
| Clinical outcomes | ||||||
| Cure/Improve | 22 | 7(18.9) | 15(51.7) | 7.873c2 | 0.005 | |
| Death | 44 | 30(81.1) | 14(48.3) | |||
| Underlying conditions | ||||||
| Diabetes | 14 | 7(18.4) | 7(24.1) | 0.325c2 | 0.568 | |
| Hypertension | 37 | 19(50.0) | 18(62.1) | 0.969c2 | 0.325 | |
| Tumor | 5 | 2(5.3) | 3(10.3) | 0.645f | ||
| COPD | 1 | 0(0.0) | 1(3.4) | 0.433f | ||
| Hospitalization time (days) | 23.3±16.6 | 23.6±15.6* | 23.0±18.1 | 477.5b | 0.449 | |
| Laboratory test results | ||||||
| SO2 (%) | 92.5(85,95) | 90(84.5,95)* | 93(88,95.5)* | 462.5b | 0.343 | |
| PLT (109/L) | 153(105.5,212.5) | 127(98.25,179) | 185(112,247) | 731.0b | 0.023 | |
| WBC count (109/L) | 9.9±4.4 | 9.8±3.9 | 10.0±4.9 | 0.180a | 0.858 | |
| Neutrophil count (109/L) | 8.80±4.30 | 8.80±3.89 | 8.80±4.87 | -0.003a | 0.997 | |
| Neutrophil % | 89.9(80.1,92.1) | 89.95(86.6,93.13)* | 89.8(78.5,91.4) | 420.5b | 0.321 | |
| Lymphocyte count (109/L) | 0.59(0.42,0.96) | 0.55(0.39,0.72) | 0.64(0.48,1.12) | 666.5b | 0.146 | |
| Albumin (g/L) | 29.88±5.51 | 28.68±4.79 | 31.44±6.06 | 2.080a | 0.041 | |
| LDH (U/L) | 434(328.5,592) | 472(339.25,661) | 430(321,502) | 451.0b | 0.208 | |
| Maximum creatinine value during hospitalization (μmol/L) | 146(92.45,291.35) | 198.85(123.62,340.95) | 132.7(63.1,214) | 364.0b | 0.018 | |
| High-sensitivity troponin I | 36(14.6,140.5) | 46.6(19.9,184.25)* | 23.7(12.55,70.82)* | 354.0b | 0.229 | |
| D-dimer (ug/mL) | 3.31(0.88,8) | 2.26(0.92,8)* | 3.53(0.88,6.98) | 513.5b | 0.915 | |
| CRP (mg/L) | 96.7(43.8,143.8) | 97.76(54.34,143.57)* | 89.16(33.93,143.8) | 480.0b | 0.583 | |
| Ferritins (μg/L) | 1614(837,20000) | 1618.59(907.86,2000)* | 1447.99(851.62,2000)* | 183.0b | 0.522 | |
| PCT (ng/mL) | 0.24(0.12,0.41) | 0.3(0.14,0.49)* | 0.23(0.12,0.27)* | 276.5b | 0.120 | |
| Maximum IL-6 (pg/mL) | ||||||
| <P25 (<=250) | 15 | 11(28.9) | 4(13.8) | 4.438c2 | 0.109 | |
| P25~P75 (250 -4000) | 32 | 14(36.8) | 18(62.1) | |||
| >=P75(>=4000) | 20 | 13(34.2) | 7(24.1) | |||
| Lung CT main performance | Ground glass | 29 | 12(35.3) | 17(65.4) | 5.342c2 | 0.021 |
| Consolidation | 31 | 22(64.7) | 9(34.6) | |||
| Treatments | ||||||
| Antiviral | 64 | 35(97.2) | 29(100.0) | 1.000f | ||
| Tracheal cannula | 56 | 34(100.0) | 22(75.9) | 0.003f | ||
| Tracheotomy | 13 | 8(24.2) | 5(17.9) | 0.368c2 | 0.544 | |
| Antibiotic | 62 | 35(97.2) | 27(96.4) | 1.000f | ||
| Hormone | 47 | 30(83.3) | 17(70.8) | 1.326c2 | 0.250 | |
| Globulin | 38 | 24(77.4) | 14(56.0) | 2.911c2 | 0.088 | |
| ACEI/ARB | 4 | 1(3.3) | 3(13.6) | 0.299f | ||
| Convalescent plasma | 10 | 7(21.2) | 3(11.1) | 0.485c1 | 0.486 | |
| Traditional Chinese medicine and pharmacy | 18 | 8(25.8) | 10(41.7) | 1.546c2 | 0.214 | |
| High flow nasal catheter oxygen inhalation | 49 | 25(75.8) | 24(85.7) | 0.950c2 | 0.330 | |
| Non-invasive ventilation | 40 | 23(65.7) | 17(65.4) | 0.001c2 | 0.979 | |
| Invasive mechanical ventilation | 59 | 37(100.0) | 22(75.9) | 0.002f | ||
| ECMO | 9 | 6(17.1) | 3(10.7) | 0.131c1 | 0.717 | |
| Complications | ||||||
| AKI | 49 | 30(81.1) | 19(65.5) | 2.059c2 | 0.151 | |
| Respiratory failure | 57 | 35(94.6) | 22(88.0) | 0.385f | ||
| Gastrointestinal bleeding | 25 | 16(48.5) | 9(40.9) | 0.306c2 | 0.580 | |
| Acute liver dysfunction | 41 | 26(81.2) | 15(83.3) | 0.000c1 | 1.000 | |
| Acute myocardial injury | 56 | 32(88.9) | 24(88.9) | 1.000f | ||
| ARDS | 35 | 25(71.4) | 10(47.6) | 3.175c2 | 0.075 | |
| MODS | 30 | 26(81.2) | 4(25.0) | 14.400c2 | <0.001 |
Note: a: t value by t test; b: Z value by Wilcoxon rank sum test; c1: continuity corrected χ2 value by χ2 test; c2: χ2 value by χ2 test; f: Fisher exact probability test p value.
*: contains missing values.
PLT: Blood platelets; WBC count: White blood cell count; SO2: Blood oxygen saturation; LDH: Lactate dehydrogenase; CRP: C-reactive protein; PCT: Procalcitonin; IL6: Interleukin 6; COPD: Chronic obstructive pulmonary disease; AKI: acute kidney injury.