Table 2.

Intraoperative ventilation, haemodynamics, and procedure data

	PEEP group (n = 31)	ZEEP group (n = 29)
Tidal volume (ml kg−1 of ideal body weight)	7.1 ± 0.2	7.1 ± 0.2
PEEP level
12 cmH2O	27 (87)	25 (86)
14 cmH2O	4 (13)	4 (14)
Peak pressure (cmH2O)
After intubation	21 ± 1.4	22 ± 1.6
Mid surgery	25 ± 1.8	25 ± 1.7
Before awakening	23 ± 1.8	23 ± 1.3
Plateau pressure (cmH2O)
After intubation	19 ± 1.4	20 ± 1.7
Mid surgery	23 ± 1.6	23 ± 1.7
Before awakening	20 ± 1.6	21 ± 1.4
Driving pressure (cmH2O)
After intubation	7 ± 1.3	8 ± 1.5
Mid surgery	11 ± 1.6	10 ± 1.7
Before awakening	8 ± 1.5	8 ± 1.3
Static respiratory system compliance (ml cmH2O−1)
After intubation	59 ± 11	53 ± 13
Mid surgery	43 ± 9	39 ± 10
Before awakening	53 ± 11	48 ± 9
Respiratory rate (breaths min−1)
After intubation	10 ± 0.8	10 ± 0.8
Mid surgery	12 ± 1.5	12 ± 1.9
Before awakening	14 ± 1.6	14 ± 2.0
End tidal CO2 (kPa)
After intubation	5.2 ± 0.3	5.2 ± 0.4
Mid surgery	5.3 ± 0.3	5.4 ± 0.3
Before awakening	5.8 ± 0.4	5.7 ± 0.4
Mean arterial pressure (mmHg)
After intubation	82 ± 11	80 ± 10
Mid surgery	84 ± 13	83 ± 14
Before awakening	82 ± 16	79 ± 10
Total i.v. phenylephrine (mg)	1.5 ± 0.7	1.7 ± 1.1
Total i.v. ephedrine (mg)	2.1 ± 3.7	4.1 ± 7.2
Duration of anaesthesia (min)	109 ± 28	120 ± 29
Duration of surgery (min)	66 ± 18	73 ± 18

Data are presented as mean ± SD or number (%).

Before awakening is after completed surgery and after capnoperitoneum.

IBW, ideal body weight; PEEP, positive end-expiratory pressure.