Table 2.

Effect of high positive end-expiratory pressure with recruitment manoeuvres vs. low positive end-expiratory pressure on respiratory parameters in obese patients

	Low PEEP	High PEEP	High PEEP
Variable	(n = 79)	(n = 83)	End recruitment	P a
Tidal volume ml kg-1 PBW-1
Post induction	7.2 ± 0.9	7.3 ± 0.8	14.2 ± 2.4	0.824
60 min	7.2 ± 0.9	7.3 ± 0.8	14.5 ± 2.4	0.616
120 min	7.2 ± 0.9	7.2 ± 0.8	14.3 ± 2.5	0.840
180 min	7.3 ± 0.9	7.4 ± 0.9	13.9 ± 3.0	0.462
Plateau pressure, cmH2O
Post induction	24.2 ± 4.4	26.1 ± 4.0	35.0 ± 4.1	0.004
60 min	24.4 ± 4.2	26.1 ± 4.2	35.4 ± 3.8	0.012
120 min	25.1 ± 4.1	26.4 ± 4.0	35.5 ± 5.0	0.038
180 min	25.0 ± 4.3	26.7 ± 3.8	35.4 ± 4.7	0.008
Fractional inspiratory oxygen concentration, %
Post induction	0.45 ± 0.06	0.44 ± 0.05	0.44 ± 0.05	0.215
60 min	0.45 ± 0.06	0.41 ± 0.02	0.41 ± 0.02	0.001
120 min	0.45 ± 0.06	0.41 ± 0.02	0.41 ± 0.02	<0.001
180 min	0.45 ± 0.06	0.41 ± 0.01	0.41 ± 0.01	<0.001
End-tidal carbon dioxide fraction, %
Postinduction	5.4 ± 0.4	5.4 ± 0.4	5.0 ± 0.2	0.825
60 min	5.5 ± 0.4	5.5 ± 0.4	5.0 ± 0.3	0.945
120 min	5.6 ± 0.4	5.5 ± 0.5	4.9 ± 0.3	0.876
180 min	5.7 ± 0.3	5.6 ± 0.4	5.0 ± 0.3	0.892
Driving pressure, cmH2O
Post induction	20.2 ± 4.4	14.1 ± 4.0	23.0 ± 4.1	< 0.001
60 min	20.4 ± 4.2	14.1 ± 4.2	23.4 ± 3.8	< 0.001
120 min	21.1 ± 4.1	14.5 ± 4.2	23.5 ± 5.0	< 0.001
180 min	21.0 ± 4.3	14.7 ± 3.8	23.4 ± 4.7	< 0.001
Compliance, ml cmH2O-1
Post induction	26.4 ± 7.0	31.6 ± 9.1	38.9 ± 10.6	< 0.001
60 min	25.6 ± 5.5	32.5 ± 11.2	39.0 ± 10.2	< 0.001
120 min	24.2 ± 4.5	30.8 ± 8.4	39.2 ± 10.0	< 0.001
180 min	22.8 ± 4.2	30.2 ± 7.5	39.8 ± 9.9	< 0.001

Data are presented as mean ± standard deviation.

PBW, predicted body weight.

^aHigh PEEP vs. low PEEP.