Transcript Vital Signs in Clarifying the Diagnosis and

Vital Signs in Clarifying the
Diagnosis and Guiding Therapy
Pieter J De Wet, MD, MD(H), FAAFP,
ABHIM
QHI Wellness, Tyler, TX,
Presentation Objectives:
• To learn how to interpret & use information from
vital signs (BP, pulse, tilt-test & body
temperature) to clarify underlying diagnosis
• To learn how to use BP, pulse, tilt-test & body
temperature to guide therapies
• To learn how to interpret and manage low or high
blood pressure readings, slow or fast heart rate,
abnormal heart rhythms and low AM axillary
temperatures from an integrative medical
perspective.
Synopsis:
• During this presentation I will be reviewing the subject of vital signs
obtained as part of a medical exam to help participants understand
how to obtain accurate vital signs readings and how to interpret
them as part of an integrative medical work-up.
• I will also be discussing what further work-ups might be appropriate
based on the patient’s vital signs and what integrative therapies
might be most helpful in treating patients with certain findings on
vital signs.
• We will include discussion of low and high resting blood pressure
readings, tilt testing, abnormal pulse readings, including high or low
pulse rate and abnormal rhythms.
• We will also be discussing early AM axillary temperature readings,
how to interpret them and how to treat based on findings.
Pulse:
• low heart rate,
• high heart rate: low stroke volume, increased
pulse rate, weakened heart, increased
sympathetic drive
• arrhythmia
Hypertension
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Persistent elevation of arterial blood pressure (BP)
~72 million Americans (31%) have BP > 140/90 mmHg
Most patients asymptomatic
Increasing prevalence with aging of population and
epidemic of overweight
Control of BP leads to a reduction in event
Control of BP leads to a reduction in events
Approximately 50% reduction in heart failure
Approximately 40% reduction in stroke
Approximately 20-25% reduction in MI
Guidelines in measuring BP
• Condition: – Posture (sitting, supine, standing)
– Circumstances (no caffeine, no smoking)
• Equipment:
– Cuff size
– Manometer
• Technique:
– Number of readings
– Performance
– Recordings
Target-Organ Damage
• Brain: stroke, transient ischemic attack,
dementia
• Eyes: retinopathy
• Heart: left ventricular hypertrophy, angina
• Kidney: chronic kidney disease
• Peripheral Vasculature: peripheral arterial
disease
Etiology of Hypertension
• Essential hypertension:
– > 90% of cases
– Hereditary component
• Secondary hypertension:
– < 10% of cases
• Common causes:
– chronic kidney disease,
– renovascular disease
• Other causes: Rx drugs, street drugs, natural
products, food, industrial chemicals
Blood Pressure Readings
• CLASSIFICATION
– Optimal
– Normal
– High Normal
– Stage 1 Hypertension
– Stage 2 Hypertension
– Stage 3 Hypertension
<120
<130
130-139 or
140-159 or
≥ 160 or
≥ 180 or
<80
<85
85-89
90-99
≥ 100
≥ 110
Clinical Controversy
• White coat hypertension: elevated BP in clinic
followed by normal BP reading at home
• Aggressive treatment of white coat
hypertension is controversial
• Patients with white coat hypertension may
have increased CV risk compared to those
without such BP changes
Classification for Adults
• Classification based on average of > 2 properly
measured seated BP measurements from > 2
clinical encounters
• If systolic & diastolic blood pressure values give
different classifications, classify by highest
category
• > 130/80 mmHg: above goal for patients with
diabetes mellitus or chronic kidney disease
• Prehypertension: patients likely to develop
hypertension
Clinical Controversy
• Ambulatory BP measurements may be more
accurate & better predict target-organ
damage than manual BP measurements using
a sphygmomanometer in a clinic setting (gold
standard)
• Many patients may be misdiagnosed,
misclassified because of poor technique, daily
BP variability, white coat HTN
JNC 8 “Cliff Notes”
• Treat to 150/90 mm Hg in patients over age 60 and 140/90
for everybody else.
• Any of 4 classes of drugs could be chosen.
• Destination is important and not the journey.
• Recommendation 1
• There is moderate to high quality evidence from RCTs that
in the general population aged 60 years or older, treating
high BP to a goal of lower than 150/90 mm Hg reduces
stroke, heart failure, and coronary heart disease (CHD).
• There is also evidence (albeit low quality) that setting a goal
SBP of lower than 140 mm Hg in this age group provides no
additional benefit compared with a higher goal SBP of 140
to 160 mm Hg or 140 to 149 mm Hg
JNC 8 “Cliff Notes”
• Recommendation 4
• The panel cannot make a recommendation for a
BP goal for people aged 70 years or older with
GFR less than 60 mL/min/1.73m2
• No outcome trials reviewed by the panel
included large numbers of adults older than 70
years with CKD.
• Antihypertensive treatment should be
individualized, taking into consideration factors
such as frailty, comorbidities, and albuminuria.
When should high blood pressure be
treated?
• In men 45 -74 significant risk of death elevations begin at SBP of
≥165, serious risk elevations begin at ≥185 according to
Framingham Study
• SBP ≤105 risk of death elevations as high as that ≥175
• Risk of death rises by 1% per year above 90th percentile vs the
bottom 20%. This corresponds with SBP of 159 for men 45-54; 173
for men 55-64; 184 for men 65-74; 165 for women 45-54; 183 for
women 55-64; 190 for women 65-74
• People with SBP lower than these levels for each age group or sex
should not be treated for high blood pressure.
• Evidence of benefit in treating DBP ≥95 is robust for reducing
morbidity, disability and mortality from cardiovascular disease, and
NOT robust in those with DBP <95 (15% of men over 45 years old).
With allowance for age, only top 5% should be treated.
What causes hypertension?
• Stress
• Nutrient deficiencies: Omega 3 fatty acids, Vitamin D,
L-arginine, which is the source of the blood vessel
“relaxing factor” Nitric Oxide as well as L-lysine,
vitamin C, magnesium, calcium, potassium, coenzyme
Q10, chromium, Vitamin B6.
• Other factors: poor diet, high sugar, high starch, high
grain, partially hydrogenated fats, GMO foods, low
vegetable and fruit intake, toxins like heavy metals,
insulin resistance, pharmaceuticals (such as NSAIDS),
tobacco, lack of exercise, central obesity
• Salt: NOT a significant cause of hypertension
Low blood pressure (hypotension)
• blood pressure reading of 90 millimeters of
mercury (mm Hg) or less systolic blood
pressure (the top number in a blood pressure
reading) or 60 mm Hg or less diastolic blood
pressure (the bottom number) is generally
considered low blood pressure.
• low blood pressure can cause symptoms of
dizziness and fainting. In severe cases, low
blood pressure can be life-threatening.
Low blood pressure
• Blood pressure is considered too low only if noticeable symptoms
are present.
• Hypotension is the opposite of hypertension which is high blood
pressure. It is best understood as a physiological state, rather than a
disease. It is often associated with shock, though not necessarily
indicative of it.
• For some people who exercise and are in top physical condition,
low blood pressure is a sign of good health and fitness. For many
people, excessively low blood pressure can cause dizziness and
fainting or indicate dehydration, acute blood loss, shock, serious
heart, endocrine or neurological disorders. Severely low blood
pressure can deprive the brain and other vital organs of oxygen and
nutrients, leading to a life-threatening condition called shock.
Symptoms of Hypotension
• The cardinal symptoms of hypotension include lightheadedness or
dizziness.
• If the blood pressure is sufficiently low, fainting and often seizures
occur.
• Low blood pressure is sometimes associated with certain
symptoms, many of which are related to causes rather than effects
of hypotension:
– chest pain, shortness of breath, Irregular heartbeat, fever higher than 38.3 °C
(101 °F), headache
– stiff neck, Severe upper back pain, cough with phlegm, prolonged diarrhea or
vomiting
– dyspepsia (indigestion), dysuria (painful urination), adverse effect of
medications
– acute, life-threatening allergic reaction, seizures, loss of consciousness
– profound fatigue, temporary blurring or loss of vision
– connective tissue disorder Ehlers-Danlos Syndrome, Black tarry stools
Tilt Table Testing
• A tilt table test, occasionally called upright tilt testing, is a
medical procedure often used to diagnose dysautonomia or
syncope. Patients with symptoms of dizziness or
lightheadedness, with or without a loss of consciousness
(fainting), suspected to be associated with a drop in blood
pressure or positional tachycardia are good candidates for
this test.
• The procedure tests for causes of syncope by attempting to
cause syncope by having the patient lie flat on a special
table or bed and then be monitored with ECG and a blood
pressure monitor which measure continuous, beat to beat,
non-invasively . The table then creates a change in posture
from lying to standing.
Preparations
• Before taking the test, the patient may be instructed to fast
for a period before the test will take place and to stop
taking any medications.
• On the day of the tilt table test, an intravenous line may be
placed in case the patient needs to be given medications
quickly; however, this may influence the results of the test
and may only be indicated in particular circumstances.
• More recently, most investigators monitor cerebral
perfusion using mean flow velocity recording with
transcranial Doppler ultrasound in supine horizontal
position, during and after head-up tilt. An 18 MHz
ultrasound transducer is placed on the temporal bone
above the cheekbone, using headgear to hold the probe in
place
Procedure
• A tilt table test can be done in different ways and be modified for
individual circumstances. In some cases, the patient will be
strapped to a tilt table lying flat and then tilted or suspended
completely or almost completely upright (as if standing). Most of
the time, the patient is suspended at an angle of 60 to 80 degrees.
• Sometimes, the patient will be given a drug, such as Glyceryl
trinitrate (nitroglycerin) or isoproterenol, to create further
susceptibility to the test. In all cases, the patient is instructed not to
move.
• Symptoms, blood pressure, pulse, electrocardiogram, and
sometimes blood oxygen saturation are recorded.
• The test either ends when the patient faints or develops other
significant symptoms, or after a set period (usually from 20 to 45
minutes, depending on the facility or individualized protocol).
Diagnostic Symptoms
• A tilt table test is considered positive if the patient
experiences symptoms associated with a drop in blood
pressure or cardiac arrhythmia.
• A normal person's blood pressure will not drop
dramatically while standing, because the body will
compensate for this posture with a slight increase in
heart rate and constriction of the blood vessels in the
legs.
• If this process does not function normally in the
patient, the test could provoke signs and symptoms
ranging from minor lightheadedness to a very severe
cardiac episode, depending on the person.
Side Effects of Tilt Table Testing
• A common side effect during tilt table testing is a feeling of
heaviness and warmth in the lower extremities. This is due to blood
pooling in the legs and, to onlookers, the patient's lower
extremities may appear blotchy, pink, or red.
• Dizziness or lightheadedness are also likely to occur in susceptible
patients. Tilt table testing could provoke fainting or syncope; in fact,
this is the purpose of the test. It may not be appropriate, or indeed
even possible, to stop the test before this occurs, as the drop in
blood pressure or pulse rate associated with fainting can come on in
seconds. This is why the patient's blood pressure and ECG should be
continuously monitored during the test.
• In extreme cases, tilt table testing could provoke seizures or even
cause the heart to stop. The heart resumes beating normally upon
being returned to a flat or head-down position.
Managing Side Effects of Tilt Table
Testing
• If at any time in tilt table testing a patient
loses consciousness, he or she will be
returned to a supine or head down position
and will be given immediate medical
attention, which could include being given
fluids or perhaps atropine or a
sympathomimetic drug like epinephrine or
ephedrine which will raise blood pressure and
heart rate rapidly.
Indications for Tilt Table Testing
• The disorders that can be examined with tilt table
testing include those with the following symptoms:
– Syncope (a past or recent history of fainting),
– Dysautonomia: Autonomic symptoms may include nasal
congestion, palpitations, non-anginal chest discomfort,
recurrent queasiness, bowel and/or bladder incontinence,
nocturia (more than twice nightly), generalized flushing,
and excess or abnormal sweating.
– General symptoms included dizziness or lightheadedness,
dysania (prolonged stiffness and fogginess upon arising),
occipital headache, and inability to stand in place.
– Chronic Fatigue Syndrome, Fibromyalgia Syndrome
Indications for Tilt Table Testing: CFS/
Fibromyalgia
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Chronic Fatigue Syndrome and Fibromyalgia are frequently associated with
orthostatic intolerance, including (symptomatic) Orthostatic Tachycardia
Syndrome, and Neurally Mediated Hypotension
Argument for tilt table testing in the majority of patients with CFS/FMS include:
– The high positivity rate for orthostatic intolerance (82%) and neurally
mediated hypotension (NMH) (42%) in these patients,
– And the fact that these conditions are potentially treatable.
• The best predictors of a positive test are:
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Inability to stand in place (postural weakness / frailty)
Fainting
Flushing.
Combined, these three predictors have a sensitivity of 71% and a negative
predictive value of 75%. Thus a history of fainting, flushing, and postural
weakness [falling, failing, frailty] reasonably predicts a positive passive tilt
table test, and their absence reasonably predicts that the test will be negative.
Simple orthostatic
blood pressure measurement
• Is inadequate because the orthostatic symptoms
in CFS/FM are usually delayed. Simply having the
subject stand still while BP and HR are monitored
can suggest orthostatic instability if there are
increases in symptoms or HR, or a precipitous fall
in BP. However, this can be dangerous because
some subjects faint abruptly or develop
prolonged asystole under such circumstances, so
they are best studied in a laboratory equipped to
handle these contingencies.
References regarding Tilt Table Testing
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1. Martinez-Lavin M, Hermosillo AG, et al., “Orthostatic sympathetic
derangement in subjects
with fibromyalgia,” J Rheumatol 1998 Apr; 25(4):823-825
2. Low PA, et al., “Postural tachycardia syndrome (POTS),” Neurology 1995 Apr; 45
(4 Suppl
5): S19-25.
3. Lapp CW, “Neurally Mediated Hypotension and Symptomatic Orthostatic
Tachycardia in
CFS,” AACFS Clinical &Research Conference, San Francisco, October 1996
4. Bou-Houlaigah I et alia, “The relationship between neurally mediated
hypotension and the
chronic fatigue syndrome,” JAMA 1995; 274:961-967
5. Streeten DH and Anderson GH Jr, “Delayed orthostatic intolerance,” Arch Int
Med 1992;
152: 1066-1072.
6. Personal communication with Dr. I. Bou-Houlaigah, 1996
Abnormal Pulse
• Introduction to Arrhythmia
• An irregular heartbeat is an arrhythmia (also called
dysrhythmia). Heart rates can also be irregular. A
normal heart rate is 50 to 100 beats per minute.
Arrhythmias and abnormal heart rates don't
necessarily occur together. Arrhythmias can occur with
a normal heart rate, or with heart rates that are slow
(called bradyarrhythmias -- less than 50 beats per
minute). Arrhythmias can also occur with rapid heart
rates (called tachyarrhythmias -- faster than 100 beats
per minute). In the United States, more than 850,000
people are hospitalized for an arrhythmia each year
What are the types of arrhythmias?
• The types of arrhythmias include:
• Premature atrial contractions. These are early extra beats
that originate in the atria (upper chambers of the heart).
They are harmless and do not require treatment.
• Premature Ventricular Arrhythmias (PVCs). These are
among the most common arrhythmias and occur in people
with and without heart disease. This is the skipped
heartbeat we all occasionally experience. In some people, it
can be related to stress, too much caffeine or nicotine, or
too much exercise. But sometimes, PVCs can be caused by
heart disease or electrolyte imbalance. People who have a
lot of PVCs, and/or symptoms associated with them, should
be evaluated by a heart doctor. However, in most people,
PVCs are usually harmless and rarely need treatment.
Ventricular Arrhythmias
• There was a Holter monitoring study done by Harold Kennedy, MD
in the 1960s that showed ventricular arrhythmias (even nonsustained V-tach), when NOT treated for about 10 years, had no
higher risk of death or hospitalization than the people with no
significant arrhythmias, as long as the ventricular arrhythmia
patients had no coronary disease, cardiomyopathy or valvular heart
disease.
• There are also studies that show that all anti-arrhythmic drugs can
be pro-arrhythmic. Therefore, many doctors inappropriately treat
ventricular arrhythmias when they shouldn’t (as long as valvular
heart disease & cardiomyopathy are ruled out with echo-Doppler
and coronary disease is ruled out with stress-thallium SPECT
scanning.
Tachyrrhythmais
• Atrial fibrillation. Atrial fibrillation is a very
common irregular heart rhythm that causes the
atria, the upper chambers of the heart, to
contract abnormally.
• Atrial flutter. This is an arrhythmia caused by one
or more rapid circuits in the atrium. Atrial flutter
is usually more organized and regular than atrial
fibrillation. This arrhythmia occurs most often in
people with heart disease and in the first week
after heart surgery. It often converts to atrial
fibrillation.
Tachyarrhythmias
• Paroxysmal supraventricular tachycardia (PSVT). A rapid heart rate,
usually with a regular rhythm, originating from above the ventricles. PSVT
begins and ends suddenly. There are two main types: accessory path
tachycardias and AV nodal reentrant tachycardias (see below).
• Accessory pathway tachycardias. A rapid heart rate due to an extra
abnormal pathway or connection between the atria and the ventricles.
The impulses travel through the extra pathways as well as through the
usual route. This allows the impulses to travel around the heart very
quickly, causing the heart to beat unusually fast.
• AV nodal reentrant tachycardia. A rapid heart rate due to more than one
pathway through the AV node. It can cause heart palpitations, or heart
failure. In many cases, it can be terminated using a simple maneuvers,
such as breathing in and bearing down, and others performed by a trained
medical professional. Some drugs can also stop this heart rhythm.
Tachyarhythmias
• Ventricular tachycardia (V-tach). A rapid heart rhythm
originating from the lower chambers (or ventricles) of the
heart. The rapid rate prevents the heart from filling
adequately with blood; therefore, less blood is able to
pump through the body. This can be a serious arrhythmia,
especially in people with heart disease, and may be
associated with more symptoms. A heart doctor should
evaluate this arrhythmia.
• Ventricular fibrillation. An erratic, disorganized firing of
impulses from the ventricles. The ventricles quiver and are
unable to contract or pump blood to the body. This is a
medical emergency that must be treated with
cardiopulmonary resuscitation (CPR) and defibrillation as
soon as possible.
Bradyarrhythmias
• These are slow heart rhythms, which may arise from
disease in the heart's electrical conduction system.
Examples include sinus node dysfunction and heart block.
• Sinus node dysfunction. A slow heart rhythm due to an
abnormal SA (sinus) node. Significant sinus node
dysfunction that causes symptoms is treated with a
pacemaker.
• Heart block. A delay or complete block of the electrical
impulse as it travels from the sinus node to the ventricles.
The level of the block or delay may occur in the AV node or
HIS-Purkinje system. The heart may beat irregularly and,
often, more slowly. If serious, heart block is treated with a
pacemaker.
Is there a normal body temperature?
• Most people think of 'normal' body temperature as 37C
(98.6F), measured using a thermometer in the mouth.
• However, the concept of there being a normal body
temperature is somewhat misleading. In fact normal body
temperature can vary according to a wide range of factors
including a person's age, the time of day and whether
someone is active or not.
• The 'normal' benchmark for body temperature was
established by a 19th century German physician called Dr
Carl Wunderlich. He is credited with taking temperature
readings from thousands of patients, which led him to
propose that 37C was normal body temperature.
What is a fever?
• In most adults, an oral temperature above 100.4 °F (38
°C) or a rectal or ear temperature above 101 °F (38.3
°C) is considered a fever. A child has a fever when his or
her rectal temperature is 100.4 °F (38 °C) or higher.
• A rectal or ear (tympanic membrane) temperature
reading is slightly higher than an oral temperature
reading. A temperature taken in the armpit is slightly
lower than an oral temperature reading. The most
accurate way to measure body temperature is to take a
rectal temperature.
What can cause a fever?
• A fever may occur as a reaction to:
• Infection. This is the most common cause of a fever. Infections may
affect the whole body or a specific body part (localized infection).
• Medicines, such as antibiotics, narcotics, barbiturates,
antihistamines, and many others. These are called drug fevers.
Some medicines, such as antibiotics, raise the body temperature
directly. Other medicines interfere with the body's ability to
readjust its temperature when other factors cause the temperature
to rise.
• Severe trauma or injury, such as a heart attack, stroke, heat,
exhaustion or heatstroke or burns.
• Other medical conditions, such as arthritis, hyperthyroidism, and
even some cancers, such as leukemia, Hodgkin's lymphoma, and
liver and lung cancer.
Basal body temperature
• Is the lowest body temperature attained during rest (usually
during sleep).
• It is generally measured immediately after awakening and before
any physical activity has been undertaken, although the
temperature measured at that time is somewhat higher than the
true basal body temperature
• In women, ovulation causes an increase of one-half to one degree
Fahrenheit (one-quarter to one-half degree Celsius) in basal body
temperature (BBT);
• Monitoring of BBTs is one way of estimating the day of ovulation.
• The tendency of a woman to have lower temperatures before
ovulation, and higher temperatures afterwards, is known as a
biphasic pattern.
• Charting of this pattern may be used as a component of fertility
awareness.
Basal Temperature Test
• The Basal Temperature Test is not to be used as a
replacement for a proper medical assessment. Instead
it can help you determine whether you may have a
thyroid imbalance and a low functioning thyroid
gland in particular. Low thyroid function can cause
many symptoms ranging from fatigue to difficulty
losing weight.
• Because the thyroid gland reflects the body’s metabolic
rate and heat is generated during metabolism,
assessing body temperature can give clues regarding
the function of the thyroid gland.
Taking a Basal Temperature
• Shake down a thermometer until the mercury falls below 95
degrees Fahrenheit if using an older thermometer. Place it by your
bed at night when you retire.
• Upon waking, before getting up (yes, even to use the bathroom)
place the thermometer under your armpit for 10 minutes. Digital
thermometers may automatically stop before that. That’s fine. Try
to lay in bed as still as possible during this time. Rest and close your
eyes. Don’t get up until after the 10 minutes have passed or until a
digital thermometer has registered your temperature.
• Record the temperature, time, and date.
• Conduct the same test for at least three mornings at the same time
each day.
Assessing Your Basal Temperature Test
• A Healthy resting temperature ranges between 97.8 to 98.2 degrees
Fahrenheit.
• Natural fluctuations can occur during menstrual cycles. If you are still
menstruating, perform the test on the second, third, and fourth days of
the menstrual cycle.
• Post-menopausal women or men can conduct the tests any days of the
month.
• If your temperature is consistently lower than the range indicated above
for at least three days, this may be an indication of
hypothyroidism. Conversely, temperatures consistently higher than this
may indicate hyperthyroidism or possible infection.
• Work up may include:
– If temp is low, blood work including Thyroid-stimulating hormone (TSH), free
T3, free T4, reverse T3, and thyroid antibodies. (Normal TSH does not rule out
hypothyroidism)
– For elevated temps, do workups for inflammation and infections
Basal Temperature Testing for Fertility
or Birth Control
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Use a thermometer that reads to the tenths place (ie: xx.x) a digital thermometer is ideal.
You don't need a specifically designed thermometer for taking BBT readings. Do not use a
standard (mercury) thermometer, which isn't specific enough.
Get enough sleep and, if possible, regular sleep. Irregular sleep patterns (including less than
three hours of uninterrupted sleep) can result in false readings.
Take your temperature every day at the same time, before getting out of bed. Set an alarm
and keep the thermometer at your bedside or under your pillow. Don't stand up, walk
around, eat anything, drink anything, or engage in any kind of activity (even shaking a
mercury thermometer) until after you've taken your BBT (which is supposed to be taken at
full rest).
Make a graph on paper or on the computer, with dates on the bottom and basal temperature
on the side. You can find and print fertility charts online, as well as sign up for a fertility
charting service.
Look for a gradual or sudden rise in temperature (between 0.5 and 1.6 degrees F). Fertility
is highest during the two to three days before your basal temperature rises so if you can
observe any month-to-month patterns in when your temperature rises, you can predict the
best time to conceive (or the best time to abstain if you're using this method for birth
control).
Presentation References:
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effect of orthostatic stress type on cardiovascular control. Blood Press
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• Jones PK, Gibbons CH. - The role of autonomic testing in syncope. -Auton
Neurosci. 2014 Sep;184:40-5.
• Van Cauwenbergh D1, Nijs J, Kos D, Van Weijnen L, Struyf F, Meeus M. Malfunctioning of the autonomic nervous system in patients with chronic
fatigue syndrome: a systematic literature review. Eur J Clin Invest. 2014
May;44(5):516-26.
• Forleo C1, Guida P, Iacoviello M, Resta M, Monitillo F, Sorrentino S, Favale
S. - Head-up tilt testing for diagnosing vasovagal syncope: a meta-analysis.
Int J Cardiol. 2013 Nov 15;169(4):e49-50.
• Melish JS. - Thyroid Disease. - Clinical Methods: The History, Physical, and
Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990.
Chapter 135.
• Wittenberg C1, Zabludowski JR, Rosenfeld JB. - Overdiagnosis of
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