Table 1 Hemodynamic data at baseline and during conventional ventilation and open lung ventilation

Heart rate (beats/min)

105 ± 5

86 ± 5^**

94 ± 5

Mean arterial pressure (mmHg)

93 ± 4

104 ± 4^**

80 ± 4^*,**

Right atrial pressure (mmHg)

4.2 ± 1

5.9 ± 1^**

8.1 ± 2^**

Cardiac output (l/min)

5.3 ± 0.3

4.9 ± 0.3

4.1 ± 0.3^*,**

Right ventricular end-diastolic volume (ml)

165 ± 11

173 ± 13

148 ± 13

Right ventricular end-systolic volume (ml)

112 ± 10

119 ± 11

103 ± 11

Systolic pulmonary pressure (mmHg)

30 ± 3

31 ± 3

28 ± 2

Mean pulmonary arterial pressure (mmHg)

17 ± 3

20 ± 2

17 ± 2^*

Pulmonary capillary wedge pressure (mmHg)

9.3 ± 2

12.1 ± 3

12.5 ± 2^**

Right ventricular ejection fraction (%)

33.1 ± 1.7

33.1 ± 1.7

31.1 ± 1.9

Pulmonary vascular resistance (dynes/s/cm⁵)

126 ± 38

130 ± 34

137 ± 49

Left ventricular end-diastolic volume (ml)

66 ± 4

61 ± 3

56 ± 5^**

Systemic vascular resistance (dynes sec cm⁵)

1379 ± 120

1693 ± 139^**

1508 ± 124

Left ventricular ejection fraction (ml)

49.5 ± 1.6

53.2 ± 2.1

43.2 ± 5.6