Impact of Hyperoxia and Hypocapnia on Neurological Outcomes in Patients with Aneurysmal Subarachnoid Hemorrhage: A Retrospective Study
Table 1
Baseline characteristics of patients recruited.
Parameters
All patients (N = 244)
GOS 4-5 (N = 122)
GOS 1–3 (N = 122)
value
Age (years)
57.7 ± 14.6
52.7 ± 13.9
62.8 ± 13.6
<0.001
Male
89 (36.4)
36 (30.0)
53 (43.4)
0.024
Source of admission
0.113
General ward
38 (15.6)
20 (16.4)
18 (14.8)
Operation room/recovery room
181 (74.2)
94 (77.0)
87 (71.3)
Others
25 (10.2)
8 (6.6)
17 (13.9)
APACHE IV score
59 ± 31
42 ± 22
77 ± 28
<0.001
APACHE IV risk of death
0.25 ± 0.24
0.12 ± 0.14
0.37 ± 0.26
<0.001
Day 1 lowest GCS
8 ± 5
11 ± 4
6 ± 4
<0.001
WFNS grading
<0.001
1
97 (39.8)
77 (63.1)
20 (16.4)
2
22 (9.0)
11 (9.0)
11 (9.0)
3
18 (7.4)
11 (9.0)
7 (5.7)
4
40 (16.4)
12 (9.8)
28 (23.0)
5
67 (27.5)
11 (9.0)
56 (45.9)
Modified Fisher radiological grading
<0.001
1
35 (14.3)
31 (25.4)
4 (3.2)
2
26 (10.7)
17 (13.9)
9 (7.4)
3
54 (22.1)
43 (35.2)
11 (9.0)
4
129 (52.9)
31 (25.4)
98 (80.3)
Location of aneurysm
0.002
Anterior circulation
153 (62.7)
90 (73.8)
63 (51.6)
Posterior circulation
66 (27.0)
24 (19.7)
42 (34.4)
Not clear
25 (10.3)
8 (6.6)
17 (13.9)
Aneurysm maximum size (mm)
5.6 ± 5.8
5.4 ± 3.7
5.7 ± 7.3
0.658
Presence of ICH/IVH
155 (63.5)
48 (39.3)
107 (87.7)
<0.001
Presence of vasospasm
101 (41.4)
45 (36.9)
56 (45.9)
0.153
Mild (>100–130 cm/s)
24 (23.8)
15 (33.3)
9 (16.1)
Moderate (>130–200 cm/s)
57 (56.4)
24 (53.3)
33 (58.9)
Severe (>200 cm/s)
20 (19.8)
6 (13.3)
14 (25.0)
Interventions
Endovascular intervention
136 (55.7)
87 (71.3)
49 (40.2)
<0.001
Surgical clipping
53 (21.7)
31 (25.4)
22 (18.0)
0.162
External ventricular drainage
131 (53.7)
50 (41.0)
81 (66.4)
<0.001
PO2 within 24 hours of ICU admission (mmHg)
Maximum
151.2 ± 62.6
141.1 ± 43.3
161.4 ± 76.1
0.011
Minimum
92.7 ± 25.6
94.0 ± 26.8
91.4 ± 24.4
0.437
Average
119.6 ± 34.4
116.3 ± 29.9
122.8 ± 38.3
0.142
Hyperoxia >200 mmHg within 24 hours of ICU admission
39 (16.0)
12 (9.8)
27 (22.1)
0.009
PCO2 within 24 hours of ICU admission (mmHg)
Maximum
41.9 ± 11.5
39.0 ± 6.3
44.9 ± 14.4
<0.001
Minimum
33.1 ± 6.4
32.4 ± 5.2
33.7 ± 7.5
0.095
Average
37.1 ± 7.2
35.6 ± 4.6
38.7 ± 8.8
0.001
Hypocapnia <30 mmHg within 24 hours of ICU admission
81 (33.2)
39 (32.0)
42 (34.4)
0.683
Hypercapnia >45 mmHg within 24 hours of ICU admission
60 (24.6)
16 (13.1)
44 (36.1)
<0.001
Length of stay (days)
ICU
7.6 ± 6.2
6.8 ± 5.7
8.5 ± 6.6
0.036
Hospital
21.1 ± 27.5
16.5 ± 9.2
25.6 ± 37.3
0.009
Mortality
ICU
44 (18.0)
0 (0)
44 (36.1)
<0.001
Hospital
59 (24.2)
0 (0)
59 (48.0)
<0.001
30 days
57 (23.4)
0 (0)
57 (46.7)
<0.001
3 months
62 (25.4)
0 (0)
62 (50.8)
<0.001
Data presented as mean ± standard deviation (SD) and number (percentage). Abbreviations: GOS = Glasgow Outcome Scale; APACHE = Acute Physiology and Chronic Health Evaluation; GCS = Glasgow Coma Scale; WFNS = World Federation of Neurosurgical Society; ICH = intracranial hemorrhage; IVH = intraventricular hemorrhage; ICU = intensive care unit; N = number.
