Table 1.
Characteristics of patients according to the occurrence of anemia (nadir hemoglobin less than 10 g/dL) during stay in the intensive care unit and packed red blood cell transfusion status.
| All patients N = 101 |
Anemia during stay N = 48 |
No anemia during stay N = 53 |
p value | PRBC transfusion N = 21 |
No PRBC transfusion N = 80 |
p value | |
|---|---|---|---|---|---|---|---|
| Age (years), mean ± SD | 29.0 ± 14.4 | 32.1 ± 16.3 | 26.3 ± 11.9 | 0.04 | 30.8 ± 14.8 | 28.6 ± 14.3 | 0.54 |
| Male gender, N (%) | 96 (95) | 44 (91.7) | 52 (98.1) | 0.19 | 21 (100) | 75 (93.8) | 0.58 |
| Body mass index (Kg/m2), mean ± SD | 24.1 ± 4.9 | 23.4 ± 3.8 | 24.6 ± 5.6 | 0.25 | 23.3 ± 3.5 | 24.3 ± 5.2 | 0.42 |
| Preexisting diabetes, N (%) | 4 (4) | 1 (2.1) | 3 (5.7) | 0.42 | 0 (0) | 4 (5.0) | 0.58 |
| Preexisting hypertension, N (%) | 6 (5.9) | 4 (8.3) | 2 (3.8) | 1.000 | 1 (4.8) | 5 (6.3) | 1.0 |
| GCS score on admission, mean ± SD | 6.8 ± 3.5 | 6.3 ± 3.1 | 7.3 ± 3.7 | 0.15 | 6.0 ± 3.2 | 7.0 ± 3.5 | 0.25 |
| Patients with GCS score ≤ 8, N (%) | 81 (80.2) | 41 (85.4) | 40 (75.5) | 0.21 | 17 (81.0) | 64 (80.0) | 1.0 |
| APACHE II, mean ± SD | 17.9 ± 6.4 | 18.2 ± 5.0 | 17.6 ± 7.4 | 0.70 | 18.6 ± 5.0 | 17.7 ± 6.7 | 0.60 |
| Injury Severity Score, mean ± SD | 20.3 ± 7.2 | 22.3 ± 6.5 | 18.5 ± 7.4 | 0.01 | 22.0 ± 6.8 | 19.9 ± 7.3 | 0.25 |
| Type of brain injury†, N (%) | |||||||
| Subdural hematoma | 25 (24.8) | 19 (39.6) | 6 (11.3) | 0.001 | 11 (52.4) | 14 (17.5) | 0.001 |
| Epidural hematoma | 21 (20.8) | 11 (22.9) | 10 (18.9) | 0.62 | 4 (19.0) | 17 (21.3) | 1.0 |
| Subarachnoid haemorrhage | 28 (27.7) | 12 (25.0) | 16 (30.2) | 0.56 | 2 (9.5) | 26 (32.5) | 0.04 |
| Intracerebral haemorrhage | 18 (17.8) | 9 (18.8) | 9 (17.0) | 0.82 | 6 (28.6) | 12 (15.0) | 0.20 |
| Intraventricular haemorrhage | 13 (12.9) | 4 (8.3) | 9 (17.0) | 0.20 | 1 (4.8) | 12 (15.0) | 0.29 |
| Brain contusion | 19 (18.8) | 5 (10.4) | 14 (26.4) | 0.04 | 2 (9.5) | 17 (21.3) | 0.35 |
| Diffuse axonal injury | 9 (8.9) | 2 (4.2) | 7 (13.2) | 0.16 | 2 (9.5) | 7 (8.8) | 1.0 |
| Hemoglobin on admission (g/dL), mean ± SD | 14.1 ± 2.1 | 13.4 ± 1.9 | 14.7 ± 1.9 | 0.002 | 13.0 ± 2.1 | 14.4 ± 1.9 | 0.004 |
| PaO2 : FiO2 ‡, mean ± SD | 316 ± 107 | 336 ± 107 | 297 ± 104 | 0.13 | 364 ± 117 | 306 ± 103 | 0.08 |
| MAP on day 1∗ (mmHg), mean ± SD |
91 ± 8 | 91 ± 8 | 89 ± 8 | 0.58 | 95 ± 5 | 88 ± 8 | 0.04 |
| ICP on day 1∗ (mmHg), mean ± SD | 17 ± 11 | 19 ± 12 | 14 ± 8 | 0.41 | 23 ± 14 | 14 ± 7 | 0.09 |
| CPP on day 1∗ (mmHg), mean ± SD | 73 ± 10 | 73 ± 11 | 75 ± 7 | 0.63 | 71 ± 13 | 74 ± 8 | 0.47 |
| Management in the intensive care unit, N (%) | |||||||
| Mechanical ventilation | 98 (97.0) | 48 (100.0) | 50 (94.3) | 0.24 | 21 (100) | 77 (96.3) | 1.0 |
| Head injury protocol | 76 (75.2) | 42 (87.5) | 34 (64.2) | 0.01 | 19 (90.5) | 57 (71.3) | 0.07 |
| Craniotomy | 31 (30.7) | 24 (50.0) | 7 (13.2) | <0.001 | 9 (42.9) | 22 (27.5) | 0.17 |
| ICP management | 32 (31.7) | 21 (43.8) | 11 (20.8) | 0.01 | 11 (52.4) | 21 (26.3) | 0.02 |
| PRBC transfusion | 21 (20.8) | 19 (39.6) | 2 (3.8) | <0.001 | 21 (100) | 0 (0) | 0.0001 |
| Other transfusions∗∗ | 15 (14.9) | 14 (29.2) | 1 (1.9) | 0.0001 | 8 (38.1) | 7 (8.8) | 0.002 |
APACHE: Acute Physiology and Chronic Health Evaluation; CPP: cerebral perfusion pressure; GCS: Glasgow Coma Scale; ICP: intracranial pressure; MAP: mean arterial pressure; PaO2/FiO2: the ratio of partial pressure of oxygen to the fraction of inspired oxygen; PRBC: packed red blood cell; SD: standard deviation.
†One patient may have more than one type of brain injury. For example, 9 patients with subdural hematoma had other injuries.
‡Missing data for 31 patients.
∗Applies to patients who had intracranial pressure monitoring; only one patient who did not develop anemia during stay had intracranial pressure monitoring.
∗∗Platelets and/or fresh frozen plasma.