Table 1.
Patient Characteristics, Temperatures, and Intubation Status
| Temperature Group | |||
|---|---|---|---|
| Characteristic | Hypothermia (499) |
Normothermia (501) |
P-Value |
| Age, years | 52 ± 12 | 51 ± 13 | 0.22 |
| Female, n (%) | 325 (65%) | 330 (66%) | 0.84 |
| Current or Former Smoker, n (%) | 309 (62%) | 332 (66%) | 0.17 |
| History of Hypertension, n (%) | 199 (40%) | 199 (40%) | 1.00 |
| History of Coronary Artery Disease, n (%) | 35 (7%) | 18 (4%) | 0.017 |
| History of Ventricular Dysfunction, n (%) | 2 (< 1%) | 3 (1%) | 1.00 |
| History of Valvular Dysfunction, n (%) | 5 (1%) | 4 (1%) | 0.75 |
| History of Dysrhythmia, n (%) | 13 (3%) | 10 (2%) | 0.54 |
| Preoperative WFNS Score, n (%) | 0.81 | ||
| I | 332 (67%) | 328 (66%) | |
| II | 140 (28%) | 149 (30%) | |
| III | 27 (5%) | 24 (5%) | |
| Preoperative Fisher Score, n (%) | 0.81 | ||
| 1 | 30 (6%) | 24 (5%) | |
| 2 | 172 (35%) | 170 (34%) | |
| 3 | 235 (47%) | 239 (48%) | |
| 4 | 62 (12%) | 68 (14%) | |
| Aneurysm Size, mm, n (%)a | 0.07 | ||
| 1 - 11 | 403 (81%) | 401 (80%) | |
| 12 - 24 | 85 (17%) | 79 (16%) | |
| > 25 | 8 (2%) | 20 (4%) | |
| Aneurysm Location, n (%)b | 0.91 | ||
| Anterior | 458 (92%) | 457 (91%) | |
| Posterior | 41 (8%) | 43 (9%) | |
| Temperature on Arrival to Operating Room, °C | 36.8 ± 0.7 | 36.8 ± 0.6 | 0.91 |
| Temperature at 1st Aneurysm Clip, °C | 33.3 ± 0.8 | 36.7 ± 0.5 | < 0.001 |
| Temperature at End of Surgery, °C | 34.2 ± 0.9 | 36.8 ± 0.6 | < 0.001 |
| Intubated at End of Surgery, n (%) | 297 (60%) | 122 (24%) | < 0.001 |
| Temperature 2 h after Surgery, °C | 36.4 ± 1.0 | 37.1 ± 0.7 | < 0.001 |
| Intubated 2 h after Surgery, n (%) | 125 (25%) | 66 (13%) | < 0.001 |
| Intubated 24 h after Surgery, n (%) | 48 (10%) | 51 (10%) | 0.83 |
Data are expressed as mean ± SD, or number (percentage).
a
Four patients with missing data for aneurysm size; hypothermia (n = 3), normothermia (n = 1)
b
One normothermic patient with missing data for aneurysm location. Anterior Aneurysms were defined as those involving the carotid, ophthalmic, anterior choroidal, middle cerebral, anterior communicating, posterior communicating, and anterior cerebral arteries. Posterior aneurysms included those involving the vertebrobasilar and posterior inferior cerebellar arteries.
WFNS = World Federation of Neurological Surgeons