Study design: Prospective observational study of acute spinal cord-injured (SCI) patients.
Objectives: To determine how effectively mean arterial blood pressure (MAP) and spinal cord perfusion pressure (SCPP) are maintained at target levels in acute SCI patients.
Setting: Single-institution study at a Canadian level-one trauma center.
Methods: Twenty-one individuals with cervical or thoracic SCI were enrolled within 48 h of injury. A lumbar intrathecal drain was inserted for monitoring intrathecal cerebrospinal fluid pressure (ITP). The MAP was monitored concurrently with ITP, and the SCPP was calculated. Data was recorded hourly from the time of first assessment until at least the end of the 5th day post injury.
Results: All subjects had at least one recorded episode with a MAP below 80 mm Hg, and 81% had at least one episode with a MAP below 70 mm Hg. On average, subjects with cervical injuries had 18.4% of their pressure recordings below 80 mm Hg. Subjects with thoracic cord injuries had on average 35.9% of their MAP recordings <80 mm Hg.
Conclusion: It is common practice to establish MAP targets for optimizing cord perfusion in acute SCI. This study suggests that even in an acute SCI referral center, when prospectively scrutinized, the actual MAP may frequently fall below the intended targets. Such results raise awareness of the vigilance that must be kept in the hemodynamic management of these patients, and the potential discrepancy between routinely setting target MAP according to 'practice guidelines' and actually achieving them.