How should I urgently evaluate and manage a patient after thoracic endovascular aortic repair who has worsening back pain, lower‑extremity heaviness, intact toe movement, normal computed tomography, and inadequate pain control?

Urgent Spinal Cord Ischemia After TEVAR – Act Immediately

This is spinal cord ischemia (SCI) until proven otherwise, and you must initiate rescue therapy immediately—do not wait for confirmatory imaging or further deterioration. The combination of worsening back pain unresponsive to analgesics, lower extremity heaviness, and normal CT imaging after TEVAR is the classic presentation of delayed SCI, which occurs in up to 7.8% of TEVAR cases and can present up to 2 weeks postoperatively 1, 2.

Immediate Actions (Within Hours)

1. Place a Cerebrospinal Fluid Drain Emergently

• CSF drainage is the single most critical intervention and should be performed within 24 hours of symptom onset 1, 3
• Target CSF pressure <10 mmHg (ideally 7 mmHg) 4
• If a prophylactic drain was placed intraoperatively, increase drainage immediately 2
• Delayed CSF drain placement can still result in neurologic recovery even with complete motor deficits 3
• 68.9% of patients with post-TEVAR SCI improve with timely CSF drainage and multimodal therapy 2

2. Augment Spinal Cord Perfusion Aggressively

• Target mean arterial pressure (MAP) >90-100 mmHg using vasopressors if needed 1, 4
• Studies show successful treatment increased MAP from 77 to 99 mmHg 4
• In the setting of spinal ischemia, maintaining higher MAP is specifically recommended 5
• Post-TEVAR hypotension is the strongest independent risk factor for SCI (OR 8.38) 6

3. Optimize Oxygen Delivery to the Spinal Cord

• Transfuse to hemoglobin >10 g/dL (ideally >12 g/dL) 1
• Low baseline hemoglobin is protective when higher (OR 0.969 per g/dL increase), and anemia worsens outcomes 6
• Provide supplemental oxygen to maximize arterial oxygen content 1

4. Additional Rescue Therapies

• Volume loading to support MAP 1
• Consider corticosteroid bolus (used in 36.5% of rescue protocols) 2
• Consider naloxone infusion (used in 33.8% of rescue protocols) 2

Critical Diagnostic Considerations

Why CT is Normal

• CT imaging is insensitive for acute spinal cord ischemia in the first 24-48 hours
• MRI with diffusion-weighted imaging is the gold standard and will show anterior spinal artery territory infarction 3
• However, do not delay treatment to obtain MRI—the clinical diagnosis is sufficient to initiate rescue therapy 1

Clinical Red Flags You're Seeing

• Delayed onset (83% of SCI occurs hours to days post-TEVAR, median 10.6 hours) 4
• Progressive symptoms despite intact toe wiggling initially (paraparesis precedes paraplegia)
• Pain refractory to analgesics is a hallmark warning sign
• Lower extremity "heaviness" represents early motor dysfunction

Pitfalls to Avoid

1. Waiting for complete paralysis before acting—early paraparesis is your window for intervention
2. Reassurance based on normal CT—CT misses early SCI
3. Attributing symptoms to "normal postoperative pain"—back pain after TEVAR that worsens and doesn't respond to analgesics is SCI until proven otherwise
4. Delaying CSF drain placement for MRI confirmation—treat clinically first

Risk Factors Present in Your Patient

• Chronic renal insufficiency is independently associated with SCI (OR 4.39) 4
• Extent of aortic coverage (particularly if extensive thoracic coverage was performed)
• Prior aortic surgery increases risk 2

Expected Outcomes with Prompt Treatment

• Complete neurologic recovery occurs in 75% (9/12) of patients when treated early 4
• Partial recovery in an additional 17% (2/12) 4
• Permanent paraplegia rate drops to 1.5% with aggressive rescue protocols 2
• The single patient who died in one series never received timely intervention and never recovered function 4

Bottom line: This patient needs a CSF drain, MAP >90 mmHg, hemoglobin >10 g/dL, and supplemental oxygen within the next few hours. Every hour of delay reduces the chance of complete neurologic recovery.