Table 1 Variations in hemodynamics and blood gas parameters under hyperoxia and after the return to baseline FiO₂

Heart Rate (bpm)

0.813

  Hyperoxia

70 ± 20

71 ± 22

77 ± 22^##‡

0.008

  Controls

67 ± 19

66 ± 19

72 ± 25

0.086

-

  Hyperoxia

86 [70–91]

87 [81–97]

83 [72–87]*

0.008

  Controls

87 [79–101]

88 [84–97]

85 [81–92]

0.462

Body temperature (°C)

0.176

  Hyperoxia

36.1 ± 1.1

36.3 ± 0.9

36.3 ± 1.1*

0.407

  Controls

36.7 ± 0.8

36.7 ± 0.9

37.1 ± 0.8^#‡

0.010

PaO₂ (mmHg)

<0.001

  Hyperoxia

108 ± 35

433 ± 109^###***

111 ± 26^‡‡‡

<0.001

  Controls

118 ± 33

119 ± 28

115 ± 33

0.622

SaO₂ (%)

-

  Hyperoxia

99.7 [98.9–100]

100[100–100]^###***

99.8 [99.1–100]^‡‡

<0.001

  Controls

100 [99.6–100]

99.9 [99.5–100]

99.8 [99.5–100]

0.863

PaO₂/FiO₂ (mmHg)

<0.001

  Hyperoxia

290 ± 93

435 ± 111^###***

287 ± 82^‡‡‡

<0.001

  Controls

314 ± 108

315 ± 93

303 ± 99

0.330

ScvO₂ (%)

-

  Hyperoxia

79 [70–83]

86 [74–90]^###

76 [72–81]^‡‡‡

<0.001

  Controls

82 [74–84]

80 [75–85]

79 [75–84]

0.838

pH

0.696

  Hyperoxia

7.48 ± 0.07

7.49 ± 0.07

7.48 ± 0.07

0.516

  Controls

7.45 ± 0.06

7.45 ± 0.05

7.45 ± 0.06

0.966

PaCO₂ (mmHg)

-

  Hyperoxia

38 [36–42]

39 [34–42]

39 [36–42]

0.826

  Controls

38 [34–42]

39 [35–43]

41 [35–42]

0.145

Base excess (mmol/L)

0.971

  Hyperoxia

5.0 ± 5.2

5.3 ± 5.3

5.6 ± 4.9

0.430

  Controls

2.9 ± 3.8

3.1 ± 4.1

3.3 ± 3.6

0.288

Lactate (mmol/L)

-

  Hyperoxia

1.1 [0.7–1.5]

1.2 [1.1–2.0]**

1.3 [1.0–1.8]*

0.037

  Controls

0.9 [0.7–1.2]

0.9 [0.7–1.2]

0.9 [0.7–1.2]

0.616