Blood pressure and pulse
In any posture, especially standing. This is where lightheadedness, syncope, and orthostatic intolerance begin.
Patient information
Let us talk about the autonomic nervous system.
The ANS is the division of the nervous system that regulates the involuntary functions of the body. It is invisible, and that is why it is so often missed.
What it regulates, without being asked
Internal organs
Breathing, gut motility, urinary function, and sexual function.
Skin and temperature
Sweating and the temperature of the hands and feet: what thermography makes visible.
Classes of the autonomic nervous system: sympathetic and parasympathetic.
Diseases of the autonomic nervous system
Map of ANS diseases: degenerative, genetic, autoimmune, baroreflex failure, neurogenic hypertension, and miscellaneous. Santa Fe Laboratory.
What changes blood pressure and pulse in daily life
Factors that modify blood pressure and heart rate. That is why the laboratory monitors continuously and non-invasively during the challenges of daily life.
What symptoms can appear
When this system fails, blood pressure and pulse can swing on standing (orthostasis). The body may not adapt well to standing, exercise, meals, heat or cold, or cognitive and emotional stress.
Who can have dysautonomia
Children, adolescents, and adults. It may follow an infection (including COVID-19), appear in Parkinson’s disease and other synucleinopathies, in autoimmunity, in diabetes, or without a cause yet. Age does not rule it out.
You are not overthinking this. You may have been told it is only stress or anxiety, and you feel there is more to it. We take seriously what is often missed: chronic fatigue, lightheadedness, tachycardia or palpitations, and brain fog. Dysautonomia is a real condition, and your symptoms matter.
Autonomic evaluation traffic light
The laboratory’s 2026 criteria for when an autonomic evaluation is indicated. Red is not an emergency-department alert; it means testing is indicated from the start.
Autonomic evaluation assessment traffic lights, 2026. Santa Fe Clinical Research Laboratory.
Red
Always require autonomic evaluation
Memory impairment or gait disturbance with orthostatic hypotension, or isolated orthostatic hypotension without motor or cognitive symptoms.
Amber
Orthostatic intolerance without a clear etiology
Suspected small-fiber, unspecified or genetic neuropathy; resistant hypertension of unclear cause; stroke or hemorrhage in arterial border zones; spinal cord disease; special populations (pregnancy < 20 weeks, pediatrics); and refractory primary headache with orthostatic intolerance.
Green
After extensive studies, still no clear diagnosis
Fibromyalgia, chronic fatigue syndrome, unspecified dysautonomia, prior COVID-19, functional neurological disorder, or follow-up of neurally mediated vasovagal syncope and POTS already diagnosed and not responding to treatment.
What to expect
- 01At the first visit we explain what we will evaluate and why it matters.
- 02The family takes part in gathering information and in decisions.
- 03Standardized functional tests of posture, effort, and vascular load.
- 04A clear action plan, with realistic goals and dates to review progress.
- 05Support to understand management at home, at school, or at work.
How to prepare
- Bring medical history, recent changes in symptoms, and current treatments.
- Write down questions so the visit is used well.
- If possible, prior test reports and results of earlier treatments.
- A medication list with doses and timing. Comfortable clothes. If there is a risk of syncope, come with someone.
- We will send specific instructions (fasting, medicines) when the visit is confirmed. Do not stop medicines on your own.
Results and next steps
You will receive a clear report with the diagnosis, its implications, and recommendations. There will be a follow-up plan. When needed, we coordinate referral to allied specialists. This website is educational and does not replace a medical evaluation. Every patient needs an individualized assessment.
Frequently asked questions
Do I need a referral?
It is not required. If you already have notes, studies, or a letter from your physician, bring them — they shorten the path.
How long is the evaluation?
The first visit and functional tests usually take a morning. Exact timing depends on the studies indicated. We reserve time to listen.
Can I eat before the tilt-table test?
We will give instructions when you book. In general we avoid a heavy meal just before the study and confirm which medicines to take or hold. Do not stop medicines on your own.
Do you offer video visits?
Yes. Virtual visits are useful for history, review of studies, and follow-up. Tilt-table testing, EEG, and ultrasound are done on site.
Do you see children or adolescents?
Yes. The evaluation is organized for children, adolescents, and adults, with the family in the process. Write to us so we can advise on site and preparation.
Are fees listed here?
Fees and availability are confirmed when you book, according to site and type of study. We can advise by WhatsApp.
Does this replace emergency care?
No. Chest pain, acute neurological deficit, syncope with injury, or any emergency belongs in an emergency department.