Table 2.

Respiratory Measurement: Pig

PEEP	SB	Time after the Start of the Protocol
		1 h	8 h	16 h
PaO2/FiO2, mm Hg
High	+	342 ± 105	409 ± 46*	412 ± 53*
Low	+	222 ± 118	221 ± 97	246 ± 100
Plateau airway pressure, cm H2O
High	+	29 ± 4.2	26.2 ± 2.5	27 ± 2.2
Low	+	25.4 ± 2.7	25.7 ± 4.6	25 ± 3.5
Mean airway pressure, cm H2O
High	+	21.1 ± 2.7*	20 ± 2.1*	20.3 ± 1.6*
Low	+	14.8 ± 2.5	14.7 ± 2.5	14 ± 1.9
PEEP, cm H2O
High	+	15 ± 2*	15 ± 2*	15 ± 2*
Low	+	8 ± 3	7 ± 2	7 ± 2
Peak transpulmonary pressure, cm H2O
High	+	23.3 ± 4.5	21.0 ± 2.6	21.4 ± 2.3
Low	+	26.4 ± 2.7	26.0 ± 4.1	26.2 ± 4.8
Peak ∆ transpulmonary pressure, cm H2O
High	+	17.8 ± 2.0*	15.6 ± 2.7*	15.9 ± 3.4*
Low	+	26.9 ± 2.7	26.0 ± 4.1	26.2 ± 4.8
Dynamic compliance of respiratory system, ml/cm H2O
High	+	11.2 ± 2.0*	12.2 ± 2.7*	13.0 ± 2.9*
Low	+	8.5 ± 1.6	8.9 ± 4.0	9.2 ± 3.5
Vt, ml/kg
High	+	6.1 ± 0.6	5.7 ± 0.6	6.2 ± 0.8
Low	+	6.4 ± 0.7	6.0 ± 0.7	6.3 ± 1.0
Respiratory rate, breaths/min
High	+	36 ± 5*	36 ± 6*	36 ± 8*
Low	+	58 ± 4	54 ± 9	54 ± 11
PaCO2, mm Hg
High	+	67 ± 15	61 ± 17	60 ± 11
Low	+	55 ± 9	61 ± 12	60 ± 16
pH
High	+	7.3 ± 0.1	7.3 ± 0.1	7.3 ± 0.1
Low	+	7.3 ± 0.1	7.3 ± 0.1	7.3 ± 0.1

For definition of abbreviations, see Table 1.

Data presented are mean ± SD.

^*P < 0.05 compared with low PEEP + SB.