Prompt identification of triggers can help ensure effective treatment.

Approximately 17,000 spinal cord injuries (SCIs) occur each year in the United States. Patients with an SCI frequently endure multiple challenges stemming from their injuries—including issues related to breathing, skin breakdown, sexual activity, and bowel and bladder dysfunction—which can lead to autonomic dysreflexia (AD), a life-threatening condition. AD occurs when the patient’s autonomic nervous system (ANS) overreacts to an internal or external stimulus, which can trigger widespread, uncontrolled sympathetic nervous system (SNS) activation and result in vasoconstriction and an alarming spike in blood pressure. The patient or caregiver should investigate the cause and take action to address the stimulus.

If the underlying AD trigger remains unidentified or unaddressed, this defensive response quickly escalates into a crisis. For patients with SCI, AD can manifest in various ways. Some individuals may remain asymptomatic, oblivious to the lurking danger, while others endure the effects of surging blood pressure, which leads to several debilitating symptoms such as a pounding headache, profuse diaphoresis, skin blotchiness, flushed face, and bradycardia.

Given AD’s severity and potential for fatality, healthcare professionals, including nurses, as well as patients and their family members, should receive comprehensive education about its signs and symptoms. Recognizing the early warning signs of an impending AD episode can help prevent a catastrophic outcome, such as stroke, seizure, or death. By equipping healthcare providers and those affected by SCIs with the knowledge and tools to identify and manage AD, we can significantly improve the overall well-being and safety of these patients.

Effects of spinal cord injuries

The ANS (“fight-or-flight” and “rest-and-digest” responses) plays a pivotal role in regulating the human body’s functions. This intricate network of nerve fibers (afferent and efferent) transmits impulses to the brain, spinal column, and limbs. Within the ANS, we encounter the parasympathetic nervous system (PNS), which fosters the body’s serene moments to induce relaxation, decelerate pace, and facilitate digestion. Conversely, the SNS takes charge of heart rate, blood pressure, and temperature regulation, primarily gearing up the body for swift responses during moments of fight or flight.

The level of an SCI (cervical, thoracic, lumbar, or sacral) plays a crucial role in the patient’s prognosis and risk for AD. Patients with cervical injuries (C1–C8) typically have minimal or no control over their body movements or functions and frequently require mechanical ventilation, which places them at a high risk for AD. Thoracic injuries (T1–T12) have variable risk depending on the specific level of damage; patients with injuries at T6 and above are particularly prone to AD. Patients with lumbar injuries (L1–L5) and sacral injuries (S1–S5) typically experience paraplegia (paralysis of part of the body), and generally have a lower risk of AD. Understanding these distinctions can help nurses provide appropriate care and interventions.

When AD occurs, both the PNS and SNS undergo significant adaptations. Baroreflex-induced changes in blood pressure are mediated by both branches of the ANS, but disruption in the nervous system’s electrical channel as a result of SCI renders it incapable of transmitting neurological messages throughout the body. Consequently, patients lose sensation below the injury level. Should an unpleasant stimulus persist below this level, the body may respond by exhibiting signs and symptoms of AD as a distress signal, triggering bradycardia via the PNS and hypertension (frequently by more than 25 mmHg in systolic pressure) through the SNS as a protective mechanism. This abrupt surge in blood pressure can lead to severe health complications, including stroke, organ damage, or even death. The leading causes of death in patients with SCI include strokes and myocardial infarction.

Injury and risk assessment

To assess the extent of SCI and determine the potential risk of AD, providers typically conduct the American Spinal Injury Association (ASIA) sensory and motor exam on newly diagnosed patients. During the sensory component of the exam, the provider uses a safety pin to evaluate 28 dermatomes (specific areas of the skin associated with individual spinal nerves) to assess for sensation bilaterally. Dermatomes transmit sensory impulses from the skin to the spinal cord and brain, allowing the body to respond to external stimuli. When a dermatome is damaged, the affected individual loses sensation in that area, increasing the risk of AD when exposed to negative stimuli.

The ASIA exam also helps determine whether the patient has sustained a complete or incomplete SCI. In cases of complete SCI, the spinal cord can’t transmit signals below the level of injury, resulting in a loss of both sensation and motor function. Individuals with incomplete injuries may retain some level of sensation below the injury site.

AD protocol

An AD protocol, which involves healthcare team members working collaboratively to alleviate a patient’s symptoms, helps to mitigate the risk of catastrophic events. To ensure a systematic approach, a comprehensive algorithm of interventions should be readily available for use by bedside nurses and other team members as well as distributed to patients and family members. Education will help ensure nurses can efficiently implement current protocols.

When you first recognize signs of an AD episode, immediately call for assistance and then carefully position the patient at a 45-degree angle to facilitate reduced arterial pressure. Current clinical practice guidelines from the Consortium for Spinal Cord Medicine (pva.org/research-resources/consortium-for-scm) recommend sitting the patient upright and dangling the legs, if possible, in an attempt to trigger orthostasis.
To ensure patient comfort and safety, remove any constrictive clothing, including socks. Meticulously inspect the patient’s skin to identify any wounds, signs of new skin breakdowns, or issues such as ingrown nails that could potentially serve as negative stimuli and precipitate an AD episode.

If a patient has an indwelling urinary cathe­ter, closely examine it for kinks or blockages, and perform a thorough urinary flow assessment. If you detect irregularities, flush the catheter to ensure unimpeded urinary drainage. Urinary retention or infection are the most frequent causes of AD. If the patient requires straight catheterization or an indwelling urinary catheter change, consider applying lidocaine jelly for lubrication (which has vasodilating effects) about 5 minutes before.

During the course of an AD event, monitor the patient’s blood pressure and pulse at 5-minute intervals. A declining trend in blood pressure typically signifies resolution of the triggering stimulus. When systolic blood pressure falls below 150 mmHg, perform a comprehensive assessment of the bowel to rule out impaction as a potential AD trigger. In the event of impaction, manually evacuate stool using lidocaine jelly. This crucial intervention can substantially reduce or even eliminate the risk of recurrent AD events.

Should these interventions fail to ameliorate the AD episode, contact the attending physician to explain the situation and verify any standing orders for nitroglycerin paste (a vasodilator with the potential to decrease blood pressure by dilating blood vessels) application to the patient’s bare chest. If a patient can’t receive nitroglycerin, the physician may order a short-acting antihypertensive, such as labetalol (a combined beta-adrenergic and alpha-adrenergic blocker). When used intravenously, this medication can decrease blood pressure during a hypertensive crisis within 5 minutes. Some physicians order a calcium channel blocker, such as nicardipine which has a safer medical profile than labetalol, and is similar to nitroprusside.

If these interventions don’t alleviate AD, the provider will order the patient transferred to a higher-level of care, where a more comprehensive evaluation can be conducted to determine the underlying cause of the crisis.

If the patient is transferred, the team should debrief to clarify how the adverse event took place. This meeting will allow the team to reflect on implementation of the AD protocol and what changes might help to ensure better outcomes in the future.

AD at home

AD management at home requires the collective efforts of various healthcare professionals. This collaborative approach involves physicians, physical therapists (PT), occupational therapists (OT), nurses, nursing assistants, and social workers working in tandem to ensure patients and their families are well-informed about the risks and necessary precautions associated with AD.

The physician, who maintains continued contact with the patient as they progress toward discharge, develops a personalized plan of care, which frequently includes an ASIA assessment. This plan serves as a crucial roadmap for the patient’s successful transition home. PT and OT teams leverage the care plan to help the patient and family members acquire the necessary skills to perform everyday tasks and effectively manage AD episodes.
Nurses educate the patient and family about AD and the established management protocol, including the checklist of steps that will help them determine the underlying cause of an episode. Teach the patient and family how to use a blood pressure cuff to assess for AD. Teach-back sessions will help check for comprehension of this skill and other aspects of the protocol. Explain AD risk and sexual activity; a rise in blood pressure before orgasm can trigger an episode. Providers may prescribe midodrine to help bring down blood pressure for safe intercourse.

During patient education, emphasize the importance of promptly calling 911 when an AD episode persists despite initial interventions. This persistence could indicate an underlying issue, such as an infection or injury, that requires immediate medical.

Social workers help to prepare the home environment for patients with SCI. They speak with patients and their families about home modifications to meet the patient’s needs. This could involve arranging for equipment (for example, ramps or Hoyer lifts), ensuring that necessary orders are placed, and liaising with companies for installation.

Comprehensive management of AD at home is an interprofessional effort that requires seamless collaboration to educate patients and their families, develop personalized care plans, and ensure a safe and supportive home environment. This collective approach aims to empower patients and their families with the knowledge and skills they need to effectively manage AD and promote overall well-being.

Make a significant difference

AD, a potentially life-threatening medical emergency, demands immediate attention and intervention. Nurses play a crucial role in recognizing and responding to AD. With the right education and training, they can effectively manage AD emergencies and significantly reduce the potential for catastrophic outcomes in patients with SCIs. By continuously improving their knowledge and skills, nurses can make a significant difference in the lives of these patients and their families.

Pamela Bolton is a patient-aligned care team RN in outpatient primary care at the Veterans Affairs Northeast Ohio Health Care System in Cleveland. Rachel Dedo is a nursing professional development specialist in labor and delivery/antepartum at the Cleveland Clinic Foundation in Cleveland, Ohio.

American Nurse Journal. 2024; 19(10). Doi: 10.51256/ANJ102458

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Key words: autonomic dysreflexia, spinal cord injuries