Proefschrift Kerklaan

Ventilator-derived VCO 2

measurements to determine REE

The statistical analyses were performed using IBM SPSS statistics 21 forWindows (IBM, Chicago IL, USA). All statistical tests were two-sided and statistical significance was defined as a p-value <0.05.

RESULTS

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Measurements were performed in 41 children, themedian age was 2.3 years (IQR 0.3 to 8.4) and 56% were male. Seventy-two percent of the children were admitted with a medical diagnosis, mostly due to respiratory insufficiency (39%). Patient characteristics are shown in Table 1a. A controlled ventilation mode was used in 66% of the children; median fractional inspired O 2 was 0.26 (IQR 0.21 to 0.31). Metabolic measurements, performed on the 2 nd day of ICU stay (median), lasted 30 minutes on average. Ventilator settings and metabolic measurement data are shown in Table 1b. Table 1a. Patient characteristics for all children and for subgroups based on compatibility of the indirect calorimetry (IC) and ventilator method (defined as a difference ≤10% or >10% between IC and ventilator- derived VCO 2 values All children N=41 Difference ≤10% N=18 Difference >10% N=23 P-value Age (yr) Age < 3 year Median (IQR) % 2.3 (0.3-8.4) 51.2 7.4 (3.3-11.9) 22.2 0.6 (0.2-4.6) 73.9 <0.001 b 0.002 c Male sex % 56.1 55.6 56.5 0.95 c Weight (kg) Weight < 10 kg Median (IQR) % 12.7 (6.1-28.5) 46.3 22.5 (14-41.8) 16.7 6.3 (4.6-16) 69.6 0.001 b 0.002 c

Height (cm)

Median (IQR)

88 (63-135)

121 (103-150)

65 (54-98)

<0.001 b

Diagnosis Surgery Medical - Respiratory

%

0.85 c

29.3 71.7 38.7

27.8 72.2

30.4 69.6

PRISM score

Median (IQR) Median (IQR)

10 (5-16)

12 (7-16)

9 (5-17) 7 (4-11)

0.44 b 0.76 b 0.70 c 0.18 a 0.85 c 0.66 c 0.41 c 1.00 c

LOS ICU (days)

7 (4-17)

9 (4-24)

Survival

%

92.7

94.4

91.3

Temperature (ºC) Mean ± SD 37.3 ± 1.0

37.6 ± 1.2

37.1 ± 0.7

Use of medication Sedatives Catecholamines Muscle relaxants Beta blockers

%

87.8 24.4 7.3 0

88.9 27.8 11.1 0

87.0 21.7 4.3 0

P-values are calculated for differences between the two subgroups using the following tests: a Independent samples t-test, b Mann-Whitney test, c Chi-square test. IQR= Interquartile Range, PRISM= Paediatric Risk of Mortality, LOS= Length of Stay, ICU= Intensive Care Unit, SD= Standard Deviation

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