How should I manage a patient who develops limb weakness during an intravenous immunoglobulin (IVIG) infusion?

Management of Limb Weakness During IVIG Infusion

Immediately stop the IVIG infusion and assess for serious adverse reactions including thrombotic events, hypersensitivity reactions, or hemodynamic instability. 1

Immediate Actions

• Stop the infusion immediately and notify the physician 2
• Perform rapid physical assessment focusing on:
  • Vital signs (blood pressure, pulse, respiratory rate, oxygen saturation, temperature) 2
  • Neurological examination to characterize the weakness pattern (focal vs. diffuse, unilateral vs. bilateral)
  • Signs of stroke (facial droop, hemiplegia, speech changes) 3
  • Respiratory function if weakness involves respiratory muscles 2
• Switch IV line to normal saline at keep-vein-open rate 2

Critical Differential Diagnosis

Thrombotic Stroke (Most Serious)

• Acute stroke is a recognized complication of IVIG, particularly with high-dose therapy 1, 3
• Risk factors include: advanced age, hypercoagulable conditions, cardiovascular risk factors, hyperviscosity, prolonged immobilization 1
• If focal neurological deficits are present (unilateral weakness, facial droop, speech changes):
  • Activate stroke protocol immediately 3
  • Obtain emergent CT or MRI brain 3
  • Consider neurology consultation stat 2

Hypersensitivity/Infusion Reaction

• Assess for moderate-to-severe hypersensitivity 2:
  • Hypotension (SBP drop ≥30 mmHg or SBP ≤90 mmHg) 2
  • Respiratory symptoms (shortness of breath, bronchospasm) 2
  • Multi-organ involvement 2
• If hypotensive: recline patient, administer NS bolus 1000-2000 mL 2
• If severe/anaphylaxis: administer epinephrine 0.3 mg IM immediately 2

Aseptic Meningitis

• Can present with headache, fever, and neurological symptoms including weakness 2
• Resolves quickly without neurological sequelae but requires evaluation 2

Grading and Management Algorithm

Mild Weakness (Grade 1-2)

• Minimal symptoms, no limitation of self-care activities 2
• Monitor vital signs for ≥15 minutes 2
• Maintain IV access with normal saline 2
• Consider rechallenge at 50% slower infusion rate after 15 minutes if symptoms resolve completely 2
• If symptoms recur, discontinue IVIG for that session 2

Moderate-to-Severe Weakness (Grade 3-4)

• Limiting self-care activities or life-threatening 2
• Permanently discontinue the infusion 2
• Obtain neurology consultation immediately 2
• Workup includes:
  • Brain and spinal cord MRI with contrast 2
  • Consider lumbar puncture if meningitis suspected 2
  • Serum studies: CBC, comprehensive metabolic panel, coagulation studies 2
  • Assess for thrombotic complications 1

Prevention Strategies for Future Infusions

• Ensure patient is not volume depleted before initiating IVIG 1
• Use slower infusion rates, particularly in high-risk patients 2, 1, 4:
  • Start at minimum rate: 1 mg/kg/min for PI/ITP, 2 mg/kg/min for CIDP 1
  • Maximum rate should not exceed 8 mg/kg/min even if tolerated 1
• Monitor closely during first 10 minutes when immediate reactions most likely occur 2
• For patients with cardiovascular risk factors, diabetes, age >65, or renal insufficiency: administer at minimum infusion rate practicable (<8 mg/kg/min) 1
• Consider premedication (though evidence is limited): acetaminophen, antihistamines 4, 5
• Avoid IVIG in patients with known hypercoagulable states or recent thrombotic events 1

Common Pitfalls

• Failing to distinguish true neurological weakness from generalized malaise/myalgias, which are common mild adverse effects 4, 5, 6
• Resuming infusion too quickly before complete symptom resolution 2
• Not recognizing stroke risk factors before initiating high-dose IVIG 3
• Inadequate hydration status assessment prior to infusion, increasing thrombotic risk 1
• Infusing too rapidly in elderly or high-risk patients 1, 4

Documentation and Follow-up

• Document the timing of weakness onset relative to infusion start 6
• Record total dose administered before reaction 6
• Note infusion rate at time of reaction 5, 6
• Report serious adverse events per institutional protocols 1
• If thrombotic event confirmed, IVIG is contraindicated for future use in that patient 1