Table 1 Patients‘data

 Age (yrs.)

64 (57–72)

66 (60–76)

 Gender (female/male)

13/8

4/18

 Body weight (kg)

74 (61–100)

90 (74–112)

 Height (cm)

168 (155–183)

177 (159–188)

 Body mass index (kg m^− 2)

27 (22–35)

29 (23–38)

 ASA classification (I/II/III)

2/16/3

0/16/6

 STOP-BANG score

2 (1–2)

5 (3–7)

 History of smoking

6

10

 Diabetes mellitus

1

4

 Otorhinolaryngologic surgery

13

12

 Other type of Surgery

8

10

 Duration of operation (min)

70 (25–186)

76 (17–195)

 Duration of anaesthesia (min)

113 (39–330)

140 (42–236)

 SpO₂ before procedure (%)

97 (92–100)

96 (92–100)

 SpO₂ at extubation (%)

99 (91–100)

100 (81–100)

 SpO₂ at arrival intermediate care (%)

96 (88–100)

93 (88–98)

 SpO₂ lowest level (%)

91 (70–98)

92 (72–99)

 Propofol dose (mg kg^− 1 h^− 1)

6.18 (5.45–11.7)

5.84 (0.84–7.03)

 Remifentanil dose (μg kg^− 1 min^− 1)

0.16 (0.11–0.33)

0.17 (0.09–0.23)