What is autonomic dysreflexia (AD)?

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From the Guidelines

Autonomic dysreflexia (AD) is a life-threatening medical emergency that requires immediate attention to prevent severe complications, including stroke, seizures, or death, and is characterized by a sudden and dangerous spike in blood pressure in individuals with spinal cord injuries at or above the T6 level. According to the most recent guideline on adult neurogenic lower urinary tract dysfunction, diagnosis and evaluation, published in 2021 in The Journal of Urology 1, autonomic dysreflexia is a condition that occurs in patients with ongoing and persistent symptoms such as flushing, sweating, headache, blurry vision, and a sense of impending doom, despite bladder drainage. The key characteristics of AD include:

  • A sudden and significant increase in systolic blood pressure, often above 150 mmHg or 20 mmHg above baseline
  • Persistent classic symptoms such as flushing, sweating, headache, blurry vision, and a sense of impending doom
  • Occurrence in individuals with spinal cord injuries at or above the T6 level The American Urological Association guideline states that clinicians should immediately initiate pharmacologic management and escalate care in patients with ongoing and persistent AD following bladder drainage 1. Another study published in the same year, also in The Journal of Urology, emphasizes the importance of terminating urodynamic testing and/or cystoscopic procedures and immediately draining the bladder in patients who develop autonomic dysreflexia during these procedures, and continuing hemodynamic monitoring 1. In terms of management, immediate initiation of pharmacologic management and escalation of care is crucial in patients with ongoing and persistent AD, and this may involve administering fast-acting antihypertensive medications such as nifedipine or nitrates. Prevention of AD involves regular bladder and bowel management, skin care, and avoiding triggers, and is essential to reduce the risk of this life-threatening condition.

From the Research

Definition and Causes of Autonomic Dysreflexia

  • Autonomic dysreflexia (AD) is a life-threatening complication of spinal cord injury (SCI) at T6 or above, resulting in an uncontrolled sympathetic discharge in response to noxious stimuli 2, 3, 4.
  • It is caused by the division of the autonomic nervous system, leading to disastrous hypertension 3.
  • AD can be triggered by urological, gastrointestinal, or gynecological problems or manipulations, such as distention and/or irritation of the bladder or constipation 2, 4.

Symptoms and Consequences

  • The most important manifestation of AD is arterial hypertension, which can lead to cerebrovascular and cardiovascular complications, including death 4, 5.
  • If not treated promptly, AD can result in devastating complications, including stroke and possibly death 6, 5.

Treatment and Prevention

  • Initial treatment consists of recognition of the symptoms and resolution of the cause, such as prompt emptying of a patient's bladder and/or bowels 3, 4.
  • Antihypertensive therapy may be initiated in patients with high blood pressure, using medications such as nifedipine, captopril, and nitroglycerin 4.
  • Prevention is also crucial, with the goal of influencing all possible triggers of this condition, especially micturition and colon disorders 4.
  • Educating patients, their caregivers, and health professionals about AD is essential for prevention and early recognition 4.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Autonomic dysreflexia: one more way EMS can positively affect patient survival.

JEMS : a journal of emergency medical services, 2003

Research

AUTONOMIC DYSREFLEXIA.

Lijecnicki vjesnik, 2017

Research

Autonomic dysreflexia: the forgotten medical emergency.

Hospital medicine (London, England : 1998), 2005

Research

Autonomic dysreflexia: a medical emergency.

Postgraduate medical journal, 2005

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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