What are the potential solutions for a patient with syncope (loss of consciousness) while seated?

From the Guidelines

For a patient with seated syncope, the most effective management strategy is to combine lifestyle modifications, physical counterpressure maneuvers, and medications, with the goal of preventing fainting and improving quality of life. Several interventions can help manage this condition, including recognizing warning signs like lightheadedness or visual changes and immediately lying down with legs elevated to prevent fainting 1. Physical counterpressure maneuvers such as leg crossing, muscle tensing, and hand gripping can increase blood pressure when feeling faint, as they increase cardiac output and peripheral vascular resistance 1. Lifestyle modifications are essential, including:

• Adequate hydration (2-3 liters daily) to prevent dehydration and maintain blood volume 1
• Increased salt intake (8-10g daily unless contraindicated) to expand blood volume and improve orthostatic tolerance 1
• Avoiding prolonged standing and rising slowly from seated positions to reduce the risk of orthostatic hypotension
• Wearing compression stockings that extend to the waist to improve venous return and reduce blood pooling in the legs 1 Medications may be necessary in refractory cases, with:
• Fludrocortisone (starting at 0.1mg daily, potentially increasing to 0.2mg) being first-line to increase sodium retention and blood volume 1
• Midodrine (2.5-10mg three times daily, avoiding evening doses) can be added as a vasoconstrictor to improve orthostatic tolerance 1
• Droxidopa, which improves symptoms of neurogenic OH due to Parkinson disease, pure autonomic failure, and multiple system atrophy, may also be considered 1 These interventions work by addressing the underlying pathophysiology of seated syncope, which typically involves autonomic dysfunction leading to inappropriate vasodilation and/or inadequate vasoconstriction when seated, resulting in cerebral hypoperfusion. It is crucial to individualize treatment based on the patient's specific needs and medical history, and to monitor their response to therapy to adjust the treatment plan as needed 1.

From the FDA Drug Label

The patient should be cautioned to report symptoms of supine hypertension immediately. Symptoms may include cardiac awareness, pounding in the ears, headache, blurred vision, etc. Patients who experience any signs or symptoms suggesting bradycardia (pulse slowing, increased dizziness, syncope, cardiac awareness) should be advised to discontinue midodrine and should be re-evaluated.

The potential solutions for a patient with seated syncope are:

• Monitoring blood pressure: Blood pressure should be monitored carefully when midodrine is used, especially in patients with a history of orthostatic hypotension.
• Adjusting medication: The dose of midodrine may need to be adjusted to minimize the risk of supine hypertension.
• Lifestyle modifications: Patients should be advised to avoid taking their dose if they are to be supine for any length of time, and to take their last daily dose of midodrine 3 to 4 hours before bedtime to minimize nighttime supine hypertension.
• Discontinuing medication: If symptoms of supine hypertension or bradycardia occur, the patient should be advised to discontinue midodrine and should be re-evaluated 2, 2, 2.

From the Research

Potential Solutions for Seated Syncope

The potential solutions for a patient with seated syncope include:

• Conservative measures as the first line of treatment 3
• Pharmacologic treatments such as:
  • Fludrocortisone and sodium chloride to increase systemic fluid volume 3
  • Midodrine, β blockers, and norepinephrine transport inhibitors to modulate the sympathetic nervous system 3
  • Other treatments that modulate other neurotransmitters or affect heart rate 3
• A two-step therapeutic strategy, with metoprolol as the first choice and midodrine as the second line treatment in patients refractory to beta-blockers 4
• Midodrine for orthostatic hypotension and recurrent reflex syncope, which has been shown to improve patient important outcomes such as health-related quality of life, symptom improvement, and syncope recurrence 5

Diagnostic Approach

The diagnostic approach for seated syncope includes:

• A thorough history and physical examination, including orthostatic assessment 6
• Short-term risk assessment to determine the need for admission 6
• Tilt-table testing for patients with suspected reflex syncope or orthostatic hypotension 6
• Monitoring for patients with suspected cardiac syncope until a diagnosis is made 6
• The use of syncope units, which have been shown to improve the rate of diagnosis while reducing cost 6

Treatment Evaluation

The evaluation of treatment for seated syncope includes:

• A randomized double-blind placebo-controlled trial to assess the effectiveness of any treatment 3
• The use of specialized syncope evaluation units and structured questionnaires for history taking 7
• The assessment of prognostic implications and the provision of appropriate advice to prevent recurrences 7