TABLE 2. Brain Tissue Po2 Catheter Information and Physiology in 405 Patientsa.
| Variable | Mean ± SD, Median (Interquartile Range), or n (%) |
|---|---|
| Type of catheter | 236 (58.3) |
| Licox Po2 and Licox temperature probes | |
| Licox Po2/temperature combination probe | 160 (39.5) |
| Neurotrend Po2, Pco2, pH probe | 7(1.7) |
| Paratrend 7 Po2, Pco2, pH probe | 2 (0.5) |
| Location of catheter | |
| Normal brain | 159 (39.3) |
| Brain underlying evacuated hematoma | 109 (26.9) |
| Brain near contusion | 105 (25.9) |
| Contused brain | 32 (7.9) |
| Average Pbto2, mm Hg | |
| All patients | 27.6 ± 14.4 |
| Duration of Pbto2 monitoring, h | |
| Time < 10 mm Hg | 1 (0-18) |
| Time < 15 mm Hg | 11 (1-34) |
| Time < 20 mm Hg | 24 (5-50.25) |
| Pbto2 trend pattern | |
| Always ≥ 10 mm Hg | 214 (52.8) |
| Transiently < 10 mm Hg at start | 129 (31.9) |
| Persistently < 10 mm Hg | 15 (3.7) |
| Decreased to < 10 mm Hg after normal at start |
47 (11.6) |
| Average ICP, mm Hg | 19.0 ± 9.5 |
| Average MAP, mm Hg | 91.6 ± 9.2 |
| Average CPP, mm Hg | 72.6 ± 14.2 |
| Average Sjvo2, % | 73.9 ± 5.5 |
| Average ETco2, mm Hg | 31.3 ± 3.9 |
| Average Sao2, % | 99.0 ± 0.9 |
a
CPP, cerebral perfusion pressure; ICP, intracranial pressure; MAP, mean arterial pressure; Pbto2, brain tissue Po2; Sjvo2, jugular venous oxygen saturation.