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Table 1 Baseline and change echodensity over time in relation to patient characteristics

From: Diaphragm echodensity in mechanically ventilated patients: a description of technique and outcomes

Characteristics Population Relation with baseline ED50 Relation with change in ED50 from baseline
n = 34 Coefficient CI 95% p  ≤ 10-point change in ED50, n = 21 (62%)  > 10-point increase in ED50, n = 13 (38%) p
Age, yr, mean (SD) 59 (16) 0.13 (− 0.46; 0.71) 0.68 59 (16) 59 (17) 0.94
Female sex, n (%) 10 (30) 9 (− 29; 11) 0.39 5 (24) 5 (38) 0.60
Co-morbidities, n (%)
 COPD 8 (24) − 15 (− 37; 7) 0.20 4 (19) 4 (31) 0.62
 Asthma 3 (9) 35 (4; 67) 0.04 1 (5) 2 (15) 0.62
 ILD 10 (30) − 20 (− 40; 0) 0.05 6 (29) 4 (31) 1.00
 OSA 3 (9) − 8 (− 42; 26) 0.64 3 (14) 0 (0) 0.46
 CHF 2 (6) − 15 (− 56; 21) 0.47 1 (5) 1 (8) 1.00
 Cirrhosis 5 (15) 34 (10; 58) 0.01 3 (14) 2 (15) 1.00
 CKD 6 (18) 5 (− 20; 29) 0.71 3 (14) 3 (23) 0.85
 Immunocompromise 10 (30) 16 (− 4; 37) 0.13 5 (24) 5 (38) 0.50
 Diabetes 10 (30) 4 (− 17; 25) 0.71 5 (24) 5 (38) 0.50
SOFA, mean over first 72 h, mean (SD) 11 (3) 0.49 (− 2.4; 3.4) 0.74 11 (3) 11 (3) 0.98
SAPS II, mean (SD) 52 (15) − 0.09 (− 0.73; 0.55) 0.78 52 (16) 51 (13) 0.80
Primary cause of acute respiratory failure, n (%)
 Cardiovascular 2 (6) Reference 1 (5) 1 (8) 0.52   
 Respiratory 7 (21) 15 (− 28; 58) 0.33 4 (19) 3 (23)  
 Sepsis (nonpulmonary) 5 (15) 12 (− 33; 56)   3 (14) 2 (15)  
 Neurologic 2 (6) 45 (− 8; 99)   1 (5) 1 (8)  
 Postoperative 6 (18) − 5 (− 48; 39)   6 (29) 0 (0)  
 Post-transplantation 9 (26) − 1 (− 42; 41)   5 (24) 4 (31)  
 Other (hepatic, renal) 3 (9) − 5 (− 54; 43)   1 (5) 2 (15)  
 Use of NIV prior to intubation 4 (12) 3 (− 26; 32) 0.82 2 (10) 2 (15) 0.96
Primary cause of acute respiratory failure, n (%)
 Non-respiratory 15 (44) Reference 8 (38) 7 (54) 0.59   
 Respiratory 19 (56) − 9 (− 28; 9) 0.34 13 (62) 6 (46)  
Sepsis-3 criteria present in first 48 h, n (%) 31 (91) 16 (− 17; 49) 0.35 19 (90) 12 (92) 1.00
Comorbidity at baseline (≥ 1), n (%) 26 (76) 8 (− 14; 30) 0.47 14 (67) 12 (92) 0.19
Baseline PaO2/FiO2, mmHg 159 (116–241) 0.06 (− 0.02; 0.15) 0.17 138 (105–212) 168 (124–253) 0.29
Cumulative fluid balance on Day 1 of ventilation, L 0.8 (− 0.3–4.5) − 0.2 (− 1.4; 1.0) 0.72 2.1 (0.1–5.1) 0.3 (− 0.7–0.9) 0.36
Cumulative fluid balance on Day 3 of ventilation, L, mean (SD) 4.1 (5.2) 1.2 (− 1; 3) 0.24 3.7 (6.2) 4.6 (3.5) 0.60
Initial diaphragm thickness, mm 2.3 (2.1–2.5) 16 (− 3; 35) 0.10 2.3 (2.1–2.6) 2.2 (1.9–2.4) 0.49
Diaphragm thickening fraction (%), mean over first 72 h 9 (6–15) − 0.4 (− 1.5; 0.8) 0.56 9 (6–15) 10 (9–16) 0.31
Baseline ventilator settings
Mode of ventilaton, n (%)
 Controlled 32 (94) Reference 20 (95) 12 (92) 1.0   
 Partially assisted 2 (6) − 27 (− 66; 12) 0.18 1 (5) 1 (8)  
Ventilator settings
 Vt, ml/kg PBW 6.8 (6.2–7.2) − 0.7 (− 1.6; 0.2) 0.15 7.0 (6.4–7.4) 6.7 (5.7–7.0) 0.18
 Peak airway pressure, cmH2O, mean (SD) 23 (5) − 0.6 (− 2.0; 0.9) 0.45 23 (5) 24 (4) 0.52
 Set inspiratory pressure above PEEP, cmH2O* 14 (13–16) 1.2 (− 1.5; 3.9) 0.39 14 (13–16) 15 (14–18) 0.41
 PEEP, cmH2O 8 (6–10) − 0.4 (− 3.2; 2.3) 0.75 8 (5–10) 8 (8–10) 0.84
 Frequency, min-1, mean (SD) 20 (5) 0.7 (− 1.0; 2.3) 0.43 20 (4) 20 (6) 0.80
 FiO2 0.5 (0.4–0.6) − 0.2 (− 3.0; 2.6) 0.90 0.5 (0.4–0.6) 0.5 (0.4–0.8) 0.93
Arterial blood gas tensions
 pH 7.36 (7.31–7.39) − 0.09 (− 1.4; 1.2) 0.90 7.36 (7.31–7.41) 7.37 (7.32–7.39) 0.84
 PaCO2, mmHg, mean (SD) 42 (7) − 0.4 (− 1.7; 0.8) 0.50 42 (7) 41 (7) 0.54
 PaO2, mmHg, mean (SD) 104 (25) − 0.6 (− 1.6; 0.3) 0.19 98 (25) 111 (24) 0.14
  1. The respiratory primary cause of acute respiratory failure comprises lung transplantation, postoperative pulmonary endarterectomy, chronic lung rejection, exacerbation of interstitial lung disease, pneumonia, and aspiration; non-respiratory are the other diagnoses
  2. CHF = chronic heart failure; CKD = chronic kidney disease; COPD = chronic obstructive pulmonary disease; ILD = interstitial lung disease; NIV = non-invasive ventilation; OSA = obstructive sleep apnea; PBW = predicted body weight; PEEP = positive end-expiratory pressure; SAPS = Simplified Acute Physiology Score; SAS = Riker Sedation-Agitation Scale; SOFA = Sequential Organ Failure Assessment
  3. All numerical distributions are reported as median (interquartile range) unless otherwise noted
  4. *Set inspiratory pressure above PEEP = peak airway pressure—PEEP