What is the management of autonomic dysreflexia?

Management of Autonomic Dysreflexia

Autonomic dysreflexia is a life-threatening emergency requiring immediate intervention to identify and remove the triggering stimulus while managing hypertension in patients with spinal cord injuries at or above T6 level. 1

Recognition and Clinical Presentation

• Autonomic dysreflexia is characterized by sudden severe hypertension (systolic BP >150 mmHg or 20 mmHg above baseline), often accompanied by bradycardia, headache, flushing, sweating, blurry vision, and a sense of impending doom 1
• This condition occurs primarily in patients with spinal cord injuries at or above the T6 level due to disruption of normal autonomic responses to stimuli below the level of injury 1
• Bradycardia frequently accompanies the hypertension due to unopposed parasympathetic activity via the vagus nerve 1, 2

Immediate Management Algorithm

1. Position the patient upright and initiate continuous hemodynamic monitoring 1, 3

2. Identify and remove the triggering stimulus immediately 1:

   • Check for bladder distension (most common cause) - drain bladder if catheter is blocked 1, 4
   • Examine for fecal impaction and disimpact if present 1
   • Terminate any ongoing procedures such as urodynamic testing or cystoscopy 1
   • Check for pressure sores, tight clothing, or other noxious stimuli below the level of injury 1, 5

3. If symptoms persist despite stimulus removal and systolic BP remains >150 mmHg or 20 mmHg above baseline:

   • Administer rapid-acting antihypertensive medications with short half-lives 1
   • Recommended agents include:
     • Nifedipine (calcium channel blocker) 3
     • Nitrates 6
     • Phentolamine or nicardipine for severe cases 6

4. For persistent bradycardia related to autonomic dysreflexia:

   • Consider methylxanthines such as theophylline or aminophylline to target unopposed parasympathetic stimulation 1
   • In rare cases of hemodynamically significant bradycardia refractory to medical therapy, temporary pacing may be considered 1

Special Considerations

• During urological procedures: Have antihypertensive medications readily available before any urologic procedure in at-risk patients 1
• Avoid beta-blockers (including labetalol) in patients with suspected adrenergic overstimulation as they may worsen the condition 6
• Monitor for hypotension after resolution of the triggering stimulus, as patients may require fluid resuscitation once the crisis resolves 7
• For athletes with spinal cord injuries: Discourage the practice of "boosting" (intentionally triggering autonomic dysreflexia to enhance performance) due to serious health risks 1

Prevention and Education

• Educate patients about signs and symptoms of autonomic dysreflexia that warrant immediate medical attention 1
• Instruct patients to report new or worsening autonomic dysreflexia, urinary incontinence, UTIs with fever or flank pain, and difficulties with catheterization 1
• Implement regular monitoring for high-risk patients, with particular attention to bladder management 1
• Treatment with methylxanthines for bradycardia can usually be withdrawn after 4-6 weeks 1

Potential Complications

• If not promptly recognized and treated, autonomic dysreflexia can lead to serious complications including 4, 7:

  • Cerebral hemorrhage
  • Seizures
  • Cardiac arrest
  • Death

• The complications result from the sudden marked rise in blood pressure, which may rupture cerebral blood vessels or significantly increase intracranial pressure 4, 7

Common Pitfalls and Caveats

• Failure to recognize autonomic dysreflexia as the underlying cause of symptoms, particularly in emergency settings where providers may be unfamiliar with the condition 7, 5
• Treating only the symptoms (hypertension) without identifying and removing the triggering stimulus 7
• Inadequate monitoring of blood pressure during the acute episode and recovery phase 1, 7
• Using inappropriate antihypertensive agents like beta-blockers that may worsen the condition 6