Thyroid status Flashcards
What is thyroid hormone and what is its role in the body?
T3
increases metabolism resulting in weight loss and potentiates the effects of catecholamines such as adrenaline resulting in excessive sympathetic output (e.g. tachycardia, tremor, anxiety).
Low levels of circulating T3 have the opposite effect, causing weight gain, low mood, constipation, poor memory and hyporeflexia.
What equipment do you need for the thyroid exam
Stethoscope
Glass of water
Tendon hammer
Piece of paper
How should the patient be positioned in the thyroid exam
Adequately expose the patient’s neck and upper sternum.
Ask the patient to sit on a chair for the assessment.
What should you look for in the initial assessment of the patient in the thyroid exam (4)
And objects?
Weight: weight loss is typically associated with hyperthyroidism (increased metabolism), whilst weight gain is associated with hypothyroidism (decreased metabolism).
Behaviour: anxiety and hyperactivity are associated with hyperthyroidism (due to sympathetic overactivity). Hypothyroidism is more likely to be associated with low mood.
Clothing: may be inappropriate for the current temperature. Patients with hyperthyroidism suffer from heat intolerance whilst patients with hypothyroidism experience cold intolerance.
Hoarse voice: caused by compression of the larynx due to thyroid gland enlargement (e.g. thyroid malignancy).
Mobility aids: patients with hyperthyroidism can develop proximal myopathy.
Prescriptions (e.g. levothyroxine).
What are the stages of the thyroid exam
WIPERQQ
Inspection
Hands
Face
Thyroid + Auscultation
Lymph nodes
Trachea
Sternum
Further tests
What do you inspect for on the hands during the thyroid exam
Thyroid acropachy: similar in appearance to finger clubbing but caused by periosteal phalangeal bone overgrowth secondary to Graves’ disease.
Onycholysis: painless detachment of the nail from the nail bed associated with hyperthyroidism.
Palmar erythema: reddening of the palms associated with hyperthyroidism, chronic liver disease and pregnancy.
What do you assess for after inspecting the hands in the thyroid exam?
What do you do next?
Peripheral tremor
a feature of hyperthyroidism reflecting sympathetic nervous system overactivity.
To assess for evidence of a subtle peripheral tremor:
- Ask the patient to stretch their arms out in front of them.
- Place a piece of paper across the back of the patient’s hands.
- Observe for evidence of a peripheral tremor (the paper will quiver).
Assess radial pulse
What do you look for when inspecting the in the face thyroid exam
Dry skin: associated with hypothyroidism.
Excessive sweating: associated with hyperthyroidism.
Eyebrow loss: the absence of the outer third of the eyebrows is associated with hypothyroidism (although this is a rare sign).
Eye signs
What eye signs should you look for in the thyroid exam
eye pathology associated with thyrotoxicosis (e.g. Graves’ disease) including
lid retraction,
eye inflammation,
exophthalmos (also known as proptosis),
eye movement abnormalities
lid lag
How do you assess lid retraction in the thyroid exam
What might you see and what does this mean
inspect the eyes from the front and note if sclera is visible between the upper lid margin and the corneal limbus (this indicative of lid retraction).
Upper eyelid retraction is the most common ocular sign of Graves’ disease however it can be present in other thyrotoxic states (e.g. toxic multinodular goitre). Eyelid retraction is thought to occur due to sympathetic hyperactivity causing excessive contraction of the superior tarsal and levator palpebrae superioris muscles.
What do you do to assess exophthalmos
inspect the eye from the front, the side and from above.
Exophthalmos is bulging of the eye anteriorly out of the orbit. Bilateral exophthalmos develops in Graves’ disease, due to oedema and lymphocytic infiltration of orbital fat, connective tissue and extraocular muscles
Why might you look for eye inflammation in the thyroid exam
Due to lid retraction and exophthalmos, the eye is more prone to dryness and the development of conjunctival oedema (chemosis), conjunctivitis and in severe cases corneal ulceration.
How and why do you assess for ophthalmoplegia in the thyroid eye exam
ophthalmoplegia (e.g. restricted eye movement, diplopia) and pain during eye movement caused by Graves’ disease (lymphocytic infiltration of orbital fat, connective tissue and extraocular muscles):
- Ask the patient to keep their head still and follow your finger with their eyes.
- Move your finger through the various axes of eye movement (“H” shape).
- Observe for restriction of eye movements and ask the patient to report any double vision or pain.
What is lid lag
delay in the descent of the upper eyelid in relation to the eyeball when looking downward. Lid lag is most commonly associated with Graves’ disease although it can be present in other thyrotoxic states (e.g. toxic multinodular goitre). Lid lag is thought to occur secondary to a combination of lid retraction and exophthalmos.
How do you check for lid lag in the thyroid exam
- Hold your finger superiorly and ask the patient to follow it with their eyes, whilst keeping their head still.
- Move your finger in a downwards direction whilst observing the patient’s upper eyelids as the patient’s eyes follow your finger. If lid lag is present, the upper eyelids will be observed lagging behind the eyes’ downward movement, with the sclera being visible between the upper lid margin and the corneal limbus.
