Intraoperative continuous neuromonitoring of MEPs and/or SSEPs are used to identify any evidence of spinal cord ischemia. The following overview of intraoperative treatment of spinal cord ischemia assumes preoperative placement of an intra-arterial catheter for continuous monitoring of MAP and a lumbar intrathecal catheter for continuous monitoring of CSF pressure. |
Assessments and communications |
- If the neuromonitoring technician reports spinal cord ischemia, immediately communicate regarding specific evidence
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- Check anesthetic agents and doses to assess possible interference with neuromonitoring*
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- Communicate with surgeon to assess potential effects of surgical procedure on spinal cord perfusion
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- Assess MAP and prepare to treat if MAP is <80 mmHg
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- Assess CSF pressure and prepare to treat if CSF pressure is >10 mmHg
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- Calculate SCPP: SCPP = MAP minus CSF pressure
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Initial treatment |
- Increase MAP to ≥80 mmHg in 5 mmHg increments, up to 100 mmHg:
- Administer vasopressor therapy
- Expand intravascular volume (if appropriate)
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- Drain CSF via intrathecal drain to decrease CSF pressure to 8 to 10 mmHg:
- Limit CSF drainage to <20 mL during the first hour of surgery
- Limit CSF drainage to <40 mL during any four-hour period
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- Recalculate SCPP; maintain SCPP ≥70 mmHg:
- Also check CVP; if CVP>CSF pressure, increase MAP further to increase the likelihood that SCPP is maintained ≥70 mmHg
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- Ensure optimal oxygen delivery to the spinal cord:
- Maintain adequate cardiac output
- Maintain optimal O2 content in blood perfusing the spinal cord (high arterial PaO2, high Hgb saturation, adequate Hgb level ≥8 mg/dL)
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Further treatment (if evidence of spinal cord ischemia is still present) |
- Communicate with neuromonitoring technician regarding any changes in evidence of spinal cord ischemia (improving, worsening, or no change)
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- Reassess MAP; continue efforts to increase MAP up to 100 mmHg
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- Reassess CSF pressure; continue efforts to drain CSF to decrease CSF pressure to 8 to 10 mmHg
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- Recalculate SCPP; maintain SCPP ≥70 mmHg:
- Also check CVP; if CVP>CSF pressure, increase MAP further to increase the likelihood that SCPP will be maintained ≥70 mmHg
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- Consult surgeon regarding possible additional surgical treatments (eg, reimplantation of intercostal vessels, distal aortic perfusion)
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- (In some cases, there are no additional options to eliminate spinal cord ischemia; however, neuromonitoring is continued)
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Prepare for postoperative management |
- Plan for postoperative monitoring for spinal cord ischemia¶
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