II. Definition
- Hypertensive Urgency in a spine injured patient (above T7) resulting from noxious stimuli below the injury
III. Pathophysiology
- Underlying Spinal Cord Injury at or above T6 level
- Imbalanced reflex sympathetic discharge, leading to Hypertensive Urgency.
- Sympathetic spinal reflexes cause sympathetic ganglia activation and direct Vasoconstriction
- Inhibitory parasympathetic response cannot reach below the level of the spinal cord lesion.
IV. Causes: Predisposing Factors (noxious stimuli below Spinal Cord Injury)
- Distended Bladder or Urinary Tract Infection (most common)
- Constipation
- Lower extremity Fracture
- Skin dirsuption (e.g. Decubitus Ulcers, Ingrown Toenail)
V. Signs
- Systolic Blood Pressure increased 20-40 mmHg over baseline
- Altered Heart Rate (typically reflex Bradycardia)
- Anxiety
- Blurred Vision
- Facial Flushing
- Headache
- Diaphoresis above the level of injury
- Piloerection above the level of injury
- Cool and clammy below level of injury
VI. Management: Blood Pressure Management
- Elevate the head of bed to 90 degrees
- Monitor Blood Pressure frequently (every 2 to 5 minutes)
- Continue to monitor for at least 2 hours after acute episode resolution
- Nifedipine IR 10 mg sublingual
- Apply Nitroglycerin Paste 1 to 2 inches at above above level of injury
- Do not use nitrates if recent use of PDE5 Inhibitor (e.g. Viagra)
- Other agents to consider if Nitroglycerin is contraindicated
- Prazosin or Terazosin
- Captopril
- Mecamylamine
- Diazoxide
- Phenoxybenzamine
VII. Management: Elimination of provocative, noxious stimuli
- Remove any tight or restrictive clothing
- Place Foley Catheter and perform bladded irrigation
- Disimpact patient if indicated
- Assess for Pressure Ulcers and other predisposing skin lesions
VIII. Complications: Hypertensive Urgency potential sequelae
- Seizures
- Retinal Hemorrhage
- Pulmonary Edema
- Renal Insufficiency
- Myocardial Infarction
- Cerebral Hemorrhage (Hemorrhagic CVA)
- Death
IX. Resources
- Christopher and Dana Reeve Foundation: Autonomic Dysreflexia resources and wallet card
X. References
-
Email communication with Christian A. Beebe, M.D., M.B.A.
- Dr. Beebe's notes are used with his permission
- Cragg (2012) CMAJ 184(1): 66
- EMedicine: Autonomic Dysreflexia in Spinal Cord Injury (accessed 9/16/2015)