Autonomic dysreflexia

Abstract

A patient with a spinal cord injury presented to our clinic with signs and symptoms that our staff did not recognize. It was later determined to be autonomic dysreflexia. What is important to know about autonomic dysreflexia?-GE, GA Julianne Mercado, RN; Amanda Ruiz, RN; and Bridget Parsh, EdD, RN, CNS respond-Autonomic dysreflexia (AD), also known as autonomic hyperreflexia, is a potentially life-threatening acute syndrome that occurs in 20% to 70% of patients with spinal cord injury (SCI) at or above the level of T6. 1,2 Unfortunately, knowledge of AD is low among healthcare professionals. 3 Uninhibited or exaggerated sympathetic responses to noxious stimuli below the level of the SCI result in diffuse vasoconstriction and hypertension. A compensatory parasympathetic response causes bradycardia and vasodilation above the level of the SCI, but it is insufficient to decrease the BP.In most cases, urologic issues such as urinary tract infection, distended bladder, or a blocked indwelling urinary catheter can be the trigger for AD. 1 Other stimuli that can cause AD include constipation, fecal impaction, gastric ulcers, hemorrhoids, pressure injuries, ingrown toenails, and burn injuries. 1,4 Additional triggers include tight clothing, sexual activity, menstrual cramps, ovarian cysts, or bone fractures. 5 Wrinkled sheets can also trigger a patient who lays on them. Patients with AD may be unaware of these stimuli due to either absent or reduced sensation below the level of injury. 5

Autonomic dysreflexia in patients with spinal cord injury

“…Noxious stimuli below the level of the SCI trigger an exaggerated sympathetic nervous system response from T6 to L2 due to posttraumatic cord hypersensitivity and a lack of compensatory parasympathetic stimulation. Diffuse vasoconstriction occurs below the level of the SCI, typically, in the lower two-thirds of the body, and can cause a severe rise in BP 2,4. This rise in BP normally stimulates the baroreceptors in the carotid sinus and aortic arch, triggering a parasympathetic response to slow the heart rate by stimulating the vagal nerve and causing vasodilation.…”

“…However, the spinal cord lesion blocks the parasympathetic response. Although vasodilation occurs above the SCI, uncontrolled vasoconstriction occurs below it 2,4. This uncontrolled sympathetic response can cause retinal hemorrhage, seizures, stroke, pulmonary edema, or cardiac arrest 5,6…”

“…Up to 90% of those with cervical spinal or high-thoracic SCIs are likely to experience AD 2. While this disorder is very common among those with SCIs, many patients treat mild signs and symptoms at home such that when patients present to a clinic or ED with severe signs and symptoms, clinicians may not know how to recognize and treat them 2,3. Treatment delays can result in potentially fatal consequences.…”

“…Treatment delays can result in potentially fatal consequences. Rapid recognition of AD signs and symptoms and immediate treatment, sometimes as simple as unkinking a urinary drainage catheter tubing, can save a patient's life 2…”

No pain, no strain: Targin® mitigates pain and constipation following spinal cord injury

“…[11][12][13] AD can lead to potentially lifethreatening consequences such as hemorrhagic stroke, myocardial infarction, and pulmonary edema. 14,15 Controlled release 2:1 ratio oxycodone hydrochloride/naloxone hydrochloride (OXN; Targinâ, Purdue Pharma) is approved for use by Health Canada (DIN 02387425; DIN 02339609; DIN 02339617; DIN 02339625) for the treatment of severe chronic pain and has potential to ameliorate side effects such as OIC which can improve treatment adherence. 16 Studies have shown that OXN can prevent or reduce OIC, while maintaining the analgesic effects of oxycodone.…”