Table 6.

Levels of inflammation markers in lung tissue.

Marker	Group	Ventral region	Group effect	Dorsal region	Group effect
TNF-α (pg/mg)	VCV	2.8 [1.9–7.5]	n.s.	3.0 [2.4–5.8]	n.s.
	WN	2.4 [0.4–4.7]		4.3 [1.4–10.7]
	P04	3.2 [1.1–4.8]		3.8 [1.0–5.6]
	P10	1.1 [0.6–4.8]		2.9 [1.1–7.4]
IL-6 (pg/mg)	VCV	39.5 [18.9–102.8]	n.s.	28.2 [8.6–50.1]	n.s.
	WN	31.8 [18.7–50.0]		34.9 [13.7–106.3]
	P04	26.0 [14.4–59.2]		14.4 [7.0–44.8]
	P10	39.1 [23.4–60.5]		20.4 [8.4–34.9]
IL-8 (pg/mg)	VCV	133.7 [63.1–327.5]	n.s.	106.1 [62.5–286.2]	n.s.
	WN	118.0 [48.1–226.0]		125.0 [68.8–216.4]
	P04	120.3 [37.5–474.1]		88.75 [48.5–208.0]
	P10	90.6 [70.5–118.0]		101.9 [72.5–130.9]

Gene expression of Tumor necrosis factor (TNF)-α, Interleukin (IL)-6, Interleukin (IL)-8, in ventral lung regions (ventral) and dorsal lung regions (dorsal), conventional volume controlled ventilation (VCV); variable volume controlled ventilation with Gaussian white noise pattern in tidal volume (WN); variable volume controlled ventilation with periodicity of 4 cycles (P₀₄) and variable volume controlled ventilation with periodicity of 10 cycles (P₁₀). Values are shown as median and interquartile range, and were obtained from 40 animals in total (n = 10/group). There were no missing values. However, a variable number of measurements yielded values below the detection limit of the respective ELISA kit and were excluded from the analysis. The remaining numbers of values were: in ventral regions for TNF-α VCV 9, WN 8, P₀₄ 8, P₁₀ 10 animals; for IL-6 VCV 10, WN 10, P₀₄ 9, P₁₀ 10 animals; for IL-8 VCV 10, WN 10, P₀₄ 10, P₁₀ 9 animals; in dorsal regions for TNF-α VCV 9, WN 8, P₀₄ 8, P₁₀ 10 animals; for IL-6 VCV 8, WN 8, P₀₄ 9, P₁₀ 10 animals; for IL-8 VCV 10, WN 10, P₀₄ 10, P₁₀ 9 animals. Differences among groups were tested with Kruskal-Wallis test followed by Mann-Whitney U-test and Bonferroni-Holm adjustment for pairwise comparison. n.s. (non-significant at P < 0.05).