Table 2 Comparison of demographic and clinical characteristics between infants with and without cerebral oxygen desaturation (rSO₂c) events 20 % or more from baseline during surgery. Data are shown as median (min-max) or proportions (n (%))

Age (days)

8 (0–70)

2 (0–39)

0.09

Gestation (weeks)

38 (33–41)

35.5 (25–38)

0.007

Weight (kg)

3.4 (1.8–5.0)

2.81 (0.8–3.8)

0.04

Preoperative MAP^a (mmHg)

52 (36–84)

44 (33–64)

0.2

Hypotension^b (n (%))

2 (5.7 %)

0 (0 %)

0.5

Preoperative hemoglobin (g∙l⁻¹)

165 (82–231)

147.5 (98–195)

0.13

Preoperative blood lactate (mmol/l)

2.1 (0.9–5.8)

2.3 (1.7–4.3)

0.27

Preoperative mechanical ventilation (n (%))

2 (5.7 %)

5 (62.5 %)

0.000

Baseline rSO₂c (%)

83.5 (70–95)

87.5 (65.5-95)

0.8

 Intraoperative SpO₂ (%)

97.5 (91.1–99.4)

96.6 (90.5–99.9)

0.4

 Intraoperative heart rate (beats per min)

143 (115.6–166.9)

149.7 (129.2–164.7)

0.4

 Expired fraction of sevoflurane (%)

1.85 (0.72–2.7)

1.79 (0.5–2.6)

0.3

 etCO₂ during anesthesia (mmHg)

34.9 (20.9–50.7)

35.1 (21.1–49)

0.9

 Intraoperative rectal temperature (°C)

37 (36.1–38.2)

36.9 (36–37.5)

0.2

 Intraoperative MAP (mmHg)

50.0 (25.1–62.1)

39.4 (30.3–57.2)

0.06

 MAP_minrSO2c (mmHg)^d

47 (22–76)

43 (23–56)

0.16

 Vasoactive agents (n (%))

4 (11.3 %)

4 (50 %)

0.01

 Red blood cell transfusion (n (%))

2 (5.7 %)

4 (50 %)

0.001

 Postoperative blood lactate level (mmol/l)

1.45 (1.1–2.2)

1.5 (1.0–3.0)

0.83

 Hemoglobin change during surgery (g∙l⁻¹)

−21 ((−44)–18)

−35 ((−43)–23)

0.16