Table 2 Variables associated with an increase in diaphragm function* and a decrease or no change in diaphragm function between the two measurements

Time between intubation and second measure, days

5 (3–6)

4 (2–6)

Time between 2 measures, days

4 (3–5)

3 (1–5)

Sepsis at inclusion, n (%)

29 (73)

22 (42)

Age, years

61 (49–72)

63 (54–71)

Male sex, n (%)

22 (55)

34 (65)

Body mass index, kg m⁻²

24 (21–25)

25 (23–28)

SAPS2 at inclusion

58 (35–66)

54 (45–64)

SOFA at inclusion

9 (5–11)

10 (7–12)

Comorbidities, n (%)

 Active smoking

20 (50)

25 (48)

 COPD

9 (23)

12 (23)

 Diabetes

11 (28)

14 (27)

 Cirrhosis

7 (18)

10 (19)

Primary reason for ventilation, n (%)

 Acute respiratory failure

28 (70)

27 (52)

 Shock

5 (13)

7 (13)

 Cardiac arrest

1 (3)

6 (12)

 Coma

6 (15)

12 (23)

Biological variables

 PCT at inclusion, ng/ml

3 (0.3–20)

1.7 (0.9–7.3)

 Blood lactate at inclusion, mmol.l⁻¹

1.8 (1.2–3.2)

2.1 (1.4–2.9)

 PaO₂/FiO₂ at inclusion

230 (160–305)

226 (162–306)

 PaO₂/FiO₂ at second measure

280 (202–327)

260 (220–333)

Sedation

 Hypnotics at inclusion (propofol or midazolam), n (%)

33 (100) ^a

44 (100) ^c

 Sufentanyl at inclusion, n (%)

29 (88) ^a

38 (86) ^c

 Hypnotics at second measure (propofol or midazolam), n (%)

19 (56) ^b

16 (40) ^d

 Sufentanyl at second measure, n (%)

9 (26) ^b

14 (35) ^d

Organ support

 Vasopressors, n (%)

28 (70)

38 (73)

Diaphragm function

 Ptr,stim at inclusion, cmH₂O

5.8 (4.0–8.0)

10.2 (7.0–14.3)

 Ptr,stim at second measure, cmH₂O

10.5 (7.0–12.5)

6.9 (4.5–9.4)

 Absolute change in Ptr,stim, cmH₂O

3.4 (1.8–4.8)

– 1.5 (– 4.9 to – 0.6)

 Relative change in Ptr,stim, %

59 (32–78)

– 19 (– 43 to – 7)

 End-expiratory diaphragm thickness at inclusion, mm

2.3 (1.9–2.9) ^e

2.1 (1.7–2.5) ^f

 End-expiratory diaphragm thickness at second measure, mm

1.9 (1.5–2.3) ^e

2.0 (1.7–2.2) ^f