Table 3.

Intraoperative variables of the patients

Variable	TLV, Preoperatively			OLV 20 min			OLV 40 min			OLV 60 min			TLV, Postoperatively
	VCV	PCV	PCV-VG	VCV	PCV	PCV-VG	VCV	PCV	PCV-VG	VCV	PCV	PCV-VG	VCV	PCV	PCV-VG
MAP (mmHg)	83.2±11.3	84.3±9.7	85.7±10.3	78.2±12.3	77.0±14.2	79.0±12.5	80.9±12.7	81.2±9.7	82.0±11.2	84.8±10.6	82.5±11.3	84.9±11.0	83.7±14.3	85.4±13.6	82.4±14.6
HR (beats/min)	78.1±8.7	77.5±9.5	78.5±9.9	74.2±7.5	73.6±10.0	74.6±11.6	74.1±12.3	75.6±9.7	73.8±8.7	74.5±10.3	72.8±11.2	71.9±13.5	73.5±8.0	72.4.±9.1	73.4.±11.0
Ppeak (cmH2O)	16.4±4.7	16.1±5.5	15.1±6.0	26.4±6.8*	22.9±5.6*	21.6±4.8*	28.2±6.6*	22.5±4.5*,#	21.5±4.3*,#	27.9±6.3*	21.9±4.9*,#	21.5±4.0*,#	20.4±3.8	19.2 ± 5.1	18.1 ± 5.4
Pmean (cmH2O)	7.2±3.1	6.8±2.9	6.6±2.7	9.8±3.5*	8.6±2.3*	8.4±2.9*	9.1±3.9*	8.6±4.1*	8.5±3.7*	8.9±3.6*	8.8±4.0*	8.5±3.4*	7.4±3.8	7.5 ± 3.5	7.0 ± 3.2
Pplateau (cmH2O)	13.2±3.9	14.5±3.5	14.2±4.1	22.3±4.4*	22.2±3.8*	21.7±4.1*	22.9±3.2*	21.5±3.9*	20.9±4.9*	23.1±4.6*	21.5±4.3*	21.2±5.0*	16.7±3.8	17.2 ± 4.4	16.9 ± 4.0
PaO2 (mmHg)	341±78	334±72	338±85	165±39*	181±43*	182±51*	158±49*	197±55*,#	205±42*,#	161±56*	198±56*,#	208±46*,#	318±69	325 ± 80	320 ± 71
PaCO2 (mmHg)	34.7±7.1	35.9±6.8	35.9±6.1	37.6±5.6	37.4±5.2	36.1±5.2	37.9±6.1	36.9±5.9	35.9±6.2	38.0±5.4	36.9±6.9	37.1 ±6.0	34.4±5.5	33.9 ±5.9	34.3 ±6.2
SaO2 (%)	99.7±0.4	99.6±0.6	99.5±0.4	97.2±3.1	97.6± 3.7	98.4±2.4	98.1±2.3	98.5±2.4	98.9±1.9	98.7±2.0	98.4±2.9	98.5±2.0	99.0±0.9	98.9 ±1.2	99.2 ±1.0

Data are shown as mean ± SD. OLV=One-lung ventilation; TLV=Two-lung ventilation; PaCO₂=arterial carbon dioxide tension; PaO₂=arterial oxygen tension; PCV=Pressure controlled ventilation; VCV=Volume controlled ventilation; PCV-VG=Pressure controlled ventilation volume guaranteed; Pmean=mean inspiratory pressure; Ppeak=peak inspiratory pressure; Pplateau=plateau inspiratory pressure; SaO2=arterial oxygen saturation;

^* P<0.05 (baseline v others periods);

^# P<0.05 (VCV v PCV, PCV-VG).