Interventions for Hemodynamic Management
The available evidence to date regarding hemodynamic management during the acute phase of SCI has focused on the association of early aggressive support and improved neurological outcomes. No cause and effect relationships have been established.
Discussion
Two studies have examined the association of early aggressive hemodynamic management and neurological improvement over time following SCI. In a study by Vale et al. (1997), 64 patients were treated with aggressive hemodynamic support as needed to maintain a MAP above 85 mmHg while in the ICU. Medical management included the use of arterial BP catheters, Swan-Ganz pulmonary artery catheters, intravenous fluids, colloid, and vasopressors. Surgery was also performed for decompression and stabilization. Treatment was initiated early after injury, beginning within 36 hours of sustaining SCI, and follow-up examinations were performed at 6-, 12-, and 18-month intervals. Improvement by at least 1 American Spinal Injury Assessment (ASIA) grade was observed in 60% of patients with complete cervical SCI and 33% of patients with complete thoracic SCI at the time of their last examination. Improvement in neurological function after 1 year following injury was observed in 92% of patients with incomplete cervical SCI and 88% of patients with incomplete thoracic SCI. Interpretation of this outcome must be taken with caution as there is no comparator group and thus, natural recovery could be occurring alongside the effects of hemodynamic support.
A similar study by Levi et al. (1993) examined 50 patients with cervical SCI who went through invasive hemodynamic monitoring and support during their ICU stay, beginning within the first week of injury. The treatment protocol included the use of arterial line and Swan-Ganz catheters, fluid replacement, operative stabilization, and dopamine and/or dobutamine as necessary to maintain a MAP of more than 90 mmHg. At 6 weeks following injury, improvement in neurological function was observed in 40% of patients and remained the same in 42% of patients. These studies need to be interpreted with care because no cause and effect relationship was established, and recovery may have occurred regardless of hemodynamic support.
Conclusion
There is level 4 evidence (from two pre-post studies: Vale et al. 1997; Levi et al. 1993) that aggressive hemodynamic support in acute SCI patients is associated with improved neurological function.