From the Guidelines
Autonomic dysfunction after spinal cord injury can lead to life-threatening complications such as autonomic dysreflexia, and its management should prioritize prevention and prompt treatment to minimize morbidity, mortality, and improve quality of life. The impact of autonomic dysfunction on patients with spinal cord injury (SCI) is significant, and it commonly manifests as autonomic dysreflexia, orthostatic hypotension, and cardiovascular, bladder, bowel, and sexual dysfunction 1. Management begins with prevention through regular bladder and bowel care to avoid triggers. For autonomic dysreflexia, immediate treatment involves sitting the patient upright and removing the triggering stimulus, followed by antihypertensive medications like nifedipine 10mg sublingually or captopril 25mg if blood pressure remains elevated.
Some key points to consider in the management of autonomic dysfunction after SCI include:
- Orthostatic hypotension can be managed with abdominal binders, compression stockings, adequate hydration, and medications such as midodrine 2.5-10mg three times daily or fludrocortisone 0.1-0.2mg daily.
- Neurogenic bladder requires clean intermittent catheterization and anticholinergics like oxybutynin 5mg three times daily.
- Neurogenic bowel management includes scheduled bowel programs with stool softeners, suppositories, and digital stimulation.
- Sexual dysfunction may be addressed with phosphodiesterase-5 inhibitors like sildenafil 50mg as needed.
- The severity of autonomic dysfunction typically correlates with injury level, with injuries above T6 having the highest risk for autonomic dysreflexia, which can be life-threatening if not promptly treated 1.
It is essential to note that the management of autonomic dysfunction after SCI requires a multidisciplinary approach, involving cooperation between several care providers, including emergency teams, anaesthesiologists and intensivists, surgeons, and rehabilitation specialists 1. Recent progress in knowledge of the pathophysiology, prevention of complications, and techniques has changed the way SCI patients are managed, and updated recommendations should be followed to enhance neurological recovery and improve patient outcomes 1. Prevention and prompt treatment of autonomic dysfunction after SCI are crucial to minimize morbidity, mortality, and improve quality of life, and should be based on the most recent and highest quality evidence available.
From the Research
Autonomic Dysfunction in Spinal Cord Injury
The impact of autonomic dysfunction on patients with spinal cord injury (SCI) is significant, resulting in a range of complications that can severely interfere with daily living. Some of the key effects of autonomic dysfunction in SCI patients include:
- Compromised cardiovascular function, leading to conditions such as orthostatic hypotension and autonomic dysreflexia 2, 3, 4, 5, 6
- Respiratory problems, including impaired breathing and respiratory failure 2
- Urinary and gastrointestinal dysfunction, resulting in conditions such as bladder storage and emptying problems, and gastrointestinal motility disorders 2
- Thermoregulatory dysfunction, leading to impaired temperature regulation 2, 5
- Sexual dysfunction, resulting from impaired autonomic control over sexual function 2
Autonomic Dysreflexia
Autonomic dysreflexia is a potentially life-threatening condition that can occur in patients with cervical or high thoracic SCI. It is characterized by severe hypertension, often triggered by unpleasant visceral or sensory stimuli below the injury level 3, 4. The signs and symptoms of autonomic dysreflexia can vary, but severe hypertension is a dominant feature and may be fatal if left untreated 3. Radiologists and other healthcare professionals should be aware of the risk of autonomic dysreflexia in patients with SCI and take steps to prevent and manage it 3.
Management and Treatment
Management of autonomic dysfunction in SCI patients typically involves a combination of pharmacological and non-pharmacological interventions. These may include medications to regulate blood pressure and heart rate, as well as lifestyle modifications such as regular exercise and stress management 4, 5. In addition, patients with SCI should be closely monitored for signs and symptoms of autonomic dysreflexia and other complications, and receive prompt treatment if necessary 3, 4.
Cerebral Blood Flow Regulation
Cerebral blood flow regulation is also affected in patients with SCI, with alterations in cerebral autoregulation, cerebrovascular reactivity, and neurovascular coupling 6. These changes can increase the risk of transient ischemic attacks, stroke, and cognitive dysfunction, and highlight the need for further research into the effects of SCI on cerebral blood flow regulation 6.