Thyroid disorders

1. Thyroid Disorders
Balkeej Kaur
M.Sc. (N)2nd
year
AIMS,CON
Sri Muktsar Sahib

2. Thyroid Gland
 Second largest endocrine gland in body
 Small butterfly shaped gland located at
base of neck.
 Thyroid is controlled
by the hypothalmus
and pituitary

3. Functions
 Stimulates & maintains metabolic
processes
Produces thyroid hormones T3-
triiodothyronine and T4-thyroxine
These hormones regulate metabolism & affect
the growth and function of other systems in
the body
 Parathyroid gland secretes PTH to raise
serum calcium levels

4. Calcitonin
 Is another important hormone secreted by the thyroid gland.
 It is secreted in response to high plasma levels of calcium. It
reduces the plasma level of calcium by increasing its
deposition in bone.
Iodine
 Is essential to the synthesis of the thyroid gland hormones.
 Is mainly used by the thyroid.
 Deficiency alters thyroid function.
 Iodide is ingested in the diet, absorbed & its ions are converted
to iodine molecules.
 Molecules react with tyrosine (an amino acid) to form the
thyroid hormones.

5. Iodine
 Dietary Iodide is removed from the bloodstream by
means of an active pump
 The pump can concentrate iodide in the follicular sacs at
350x greater than the blood concentration
 Oxidation of iodide by thyroid peroxidase converts
iodide iodine
 Peripheral de-iodination of T4 to T3 is regulated by many
factors including health, nutritional status, and other
hormones

6. Hormones: T3 & T4
 T3 (Triiodothyronine) & T4 (Tetraiodothyronine
T4 is converted to T3 by peripheral organs
such as kidney, liver, and spleen
T3 is 10x more active than T 4

7. Hormones: T4 to T3
Only 20% of total T3 is secreted by thyroid
 Majority is formed from catalysis of T4 by 5’-
iodthryonine deiodinase (highest activity in liver
and kidney)

8. Hormones: T4
 T4-thyroxine contains 4 iodine atoms
 It is a slow-acting pre-hormone
 T4 takes 4 days to peak in blood
Half-life 7 days
 Overall effects take 6 weeks
 T3 is the active and faster-acting hormone
 The immediate effects of T3 last 1-2 days
Half-life 1.5 days

9. Hormones- TSH
 TSH
TSH is a pituitary hormone
Controlled by TRH-thyrotropin releasing
hormone from hypothalamus
Functions to stimulate thyroid hormone
production
 May enlarge thyroid (goiter) when under producing
or over producing
Labs:
 High TSH indicates low thyroid hormone= hypo
 Low TSH indicates high thyroid hormone = hyper

10. Hormones-Calcitonin & PTH
 Produced by thyroid to regulate serum
calcium levels
 Calcitonin stimulates movement of
calcium into bone
 Parathyroid hormone (PTH) opposite
effect of calcitonin

11. Functions
 Metabolic stimulants of:
 Neural and skeletal development
 Oxygen consumption at rest
 Stimulating bone turnover by increasing formation
and resorption
 Increasing number of catecholamine receptors in
heart
 Increasing production of RBC
 metabolism of carbs, fats, and protein

12. Negative Feedback System
TRH
T3 & T4 Thyroid
TSH
The disruption of
any of these
mechanisms can
cause abnormal
levels of T3 and
T4 leading to
thyroid disease

13. Diseases
 Hypothyroidism-Under Activity
 Prevalence
 Affects 5-17% of population
 Females> Males
 Higher in >60 years old
 Types
 Hashimoto’s thyroiditis
 Postoperative hypothyroidism
 Postpartum hypothyroidism
 Iatrogenic hypothyroidism

14. Diseases
 Hyperthyroidism- Over activity
 Prevalence
 Affect 5-17% of population
 Females> Males
 More common in younger persons
 Types
 Thyroid storm
 Graves disease
 Toxic thyroid nodule
 Iatrogenic hyperthyroidism

15. Assessment and Diagnostic
Findings
 Inspection: Identification of landmarks.
 Look for swelling or asymmetry.
 Palpation: Palpate the gland for size, shape,
consistency, symmetry, and the presence of
tenderness.
 Auscultate the enlarged gland to identify
localized audible vibration of a bruit. This
indicates increased blood flow necessitates
referral to a physician.

16. Thyroid Function Tests
 Thyroid function tests, TSH and free thyroxine
(FT4), are elevated in hyperthyroidism and
decreased in hypothyroidism.
 Thyroid scanning.
 Biopsy.
 Ultrasonography.

17. Labs
Thyroid Function
Test
Measurement Normal Range
Total T4 (TT4) Bound & Free T4 4.5-12.5mg/dL
Free T4 (FT4) Free T4 0.8-1.5 ng/dL
Total T3 (TT3) Bound & Free T3 80-220ng/dL
T3 Resin Uptake Binding capacity of
TBG
22-34%
TSH Thyroid stimulating
hormone
0.25-6.7U/mL
Total(T3) Bound & Free T3 80-220ng/dL

18. Labs
 Hyperthyroidism
↑FT4
↓ TSH
 Hypothyroidism
↓FT4
↑ TSH

19. Hyperthyroidism-Types
 Graves disease
 Most common form (70-80%)-autoimmune disorder.
 Autoimmune disorder in which thyroid-stimulating antibodies are
circulating in blood. These bind to thyroid cells and activate cells in
the same manner as TSH. E.g TSH does decrease slightly in the
first trimester. This corresponds with increased beta HCG levels.
The changes in TSH levels may be explained by the fact that beta
HCG is not only structurally quite similar to TSH, but it also has
thyrotropic activity. It should also be noted that the thyroid gland
itself may increase slightly in size during pregnancy.
 7 times greater in women
 Peak onset is 20-30’s(in younger)

20. Hyperthyroidism-Types
 Can be caused by:
Toxic multinodular goiter
Solitary toxic nodule
Thyroiditis
Drug-induced thryotoxicosis
Pituitary or trophoblastic tumors

21. Hyperthyroidism-Symptoms
 Weight loss
 Tachycardia
 Bulging eyes
 Nervous/Anxious
 Insomnia
 Intolerant of heat
 Goiter

22.  Patients exhibit a characteristic group of signs
and symptoms (thyrotoxicosis). The
presenting symptom is often nervousness.
 Emotionally hyperexcitable, irritable, and
apprehensive; cannot sit quietly; palpitations;
tachycardia at rest and on exertion.
 Poor heat tolerance and unusual perspiration.
 The skin is flushed continuously.
 Skin is dry and diffuse pruritus.
 Exophthalmos

23.  Increased appetite and dietary intake, weight
loss, abnormal muscular fatigability and
weakness, amenorrhea, and changes in bowel
function.
 Elevation of systolic blood pressure
 Atrial fibrillation.
 Osteoporosis and fracture.

24. Assessment and Diagnostic
Findings
 Enlarged thyroid.
 It is soft and may pulsate; with a bruit.
 Diagnosis is made on the basis of the
symptoms and ↑ in serum T4 and an increased
123
I or 125
I uptake by the thyroid in excess of
50%.

25.  Nursing Interventions
Improving Nutritional Status
 Up to six well-balanced meals of small size are
offered daily.
 Foods and fluids are selected to replace fluid
lost through diarrhea and diaphoresis.
 To reduce diarrhea, highly seasoned foods and
stimulants such as coffee, tea, cola, and
alcohol are discouraged.
 High-calorie, high-protein foods are
encouraged.
 Monitor weight, dietary intake, and nutritional
status.

26. Enhancing Coping Measures
 Reassure the patient that the emotional reactions will
be controlled with effective treatment.
 Similar reassurance needs to be made to family and
friends.
 Minimise stressful experiences for the patient.
 Keep the patient’s environment quiet and noiseless.
 The nurse encourages relaxing activities if they do
not overstimulate the patient.
 Educate patient about medications to be taken in
anticipation for surgical intervention.

27. Improving Self-esteem
 The patient with hyperthyroidism may lose self-
esteem due to changes in appearance, appetite, and
weight, and due to his inability to cope well with
family and the illness.
 Cover or remove mirrors.
 Remind family members and personnel to avoid
bringing these changes to the patient’s attention.
 Explain the temporary nature of these changes.
 Provide eye care as appropriate. Instruct the patient
on how to use eye preparations.

28. Maintaining Normal Body Temperature
 The patient with hyperthyroidism frequently
finds a normal room temperature too warm
because of an exaggerated metabolic rate and
increased heat production.
 The nurse maintains the environment at a cool,
comfortable temperature and changes bedding
and clothing as needed. Cool baths and cool or
cold fluids may provide relief.

29. Teaching Patients Self-Care
 Provide instruction and written plan about the
medications.
 Provide verbal and written instruction about
the actions and possible side effects of the
medications.
 Identify adverse effects that should be
reported.
 Provide information to the patient about what
to expect if total or subtotal thyroidectomy is
anticipated.

30. Goiter
 A diet deficient in
iodine
 Increase in thyroid
stimulating hormone
(TSH) in response to
a defect in normal
hormone synthesis
within the thyroid
gland.

31. Thyroid Storm
 Life threatening syndrome
 Decompensated hyperthyroidism
 Symptoms
Hyperthyroid symptoms with agitation,
confusion, delirium, psychosis
Gastrointestinal: Nausea/Vomiting, Abdominal
pain
Tachycardia associated with CHF

32. Thyroid Storm Treatment
 Antithyroids
 PTU 200-400mg po/NG q4-8h
 Methimazole 60-120mg/d PO/NG divided q6-8h
 Potassium Iodide 2-5 drops PO/NG q6h
 Lugol Solution-Strong Iodine10 drops po TID
 Glucorticoids: block conversion of T4 to T3
 Hydrocortisone succinate 100-200mg IV q6-8
 Dexamethasone 2mg Po/IV q6-8h
 BB
 Esmolol: 500mcg/kg/min
 Propranolol 20-80mg/dose PO/NG q4-6h

33. Hyperthyroidism-Treatment
 Drug Therapy
Beta blocker
 Atenolol 50mg-100mg po daily
 Propranolol 20-40mg po TID
Antithyroids
 Methimazole 15-30mg po daily
 Propylthiouracil (PTU) 300mg TID

34. Hyperthyroid-Treatment
 Procedural Therapy
Radionuclide albation of thyroid gland
Total thyroidectomy

35. Methimazole
 Reduces T3 & T4 production.
 Dosage
15-30mg PO daily

36. Methimazole
 Adverse Effects
Skin rash
Loss of taste
GI upset
Drowsiness
Decreased Platelets

37. Propylthiouracil -PTU
 Thio-urea derivative
 Preferred agent in pregnant women
 severe thyrotoxicosis
 Dosage
 Adults: 300-450mg/day divided q8h
 Severe cases: 600-1200mg/day
 Maintenance dose 100-150mg/day divided q 8-12
hours

38. PTU
 Adverse reactions
Rash
Itching
hives(urticaria-redness,swelling,itching)
Agranulocytosis (when bone marrow is unable
to produce mature white cells that
neutrophills)
vasculitis(inflammation pf blood vessels)

39. Carbimazole
 Dosage
15-40mg PO daily until normal function
Reduce to 5-15mg po daily maintenance dose
 Adverse Effects
Bone marrow suppression
Neutropenia
Agranulocytosis

40. Sodium Iodide I-131 (Iodotope)
 Quickly absorbed and taken up by thyroid
 No other tissue capable of retaining
radioactive iodine therefore low adverse
effects
 Dose
Adult 75-150mCi/g of thyroid x estimated
thyroid gland size
24hour radioiodine uptake
Discontinue antithyroid therapy 3-4days
before

41. Hypothyroidism
 Types:
Primary hypothyroidism
 Most common cause
 Failure of thyroid gland
 Occurs primarily in women aged 30-50 years old
 Chronic autoimmune thyroiditis or Hashimotos disease is
the most common primary hypothyroidism AND
hypothyroidism overall
Secondary Hypothyroidism
Tertiary Hypothyroidism
Other causes

42. Hypothyroidism-Symptoms
 Early symptoms are nonspecific.
 Extreme fatigue.
 Hair loss, brittle nails, dry skin, and numbness and tingling of
the fingers may occur.
 Voice may become husky [hoarse and dry].
 Menstrual disturbances & loss of libido.
 In severe hypothyroidism:
 Hypothermia & bradycardia.
 Weight gain even without ↑ in food intake.
 Thick skin, thin hair that falls out.
 Expressionless and masklike face.

43. Hypothyroidism-Symptoms
 Fatigue
 Depression
 Bradycardia
 Constipation
 Intolerant to cold

44.  Subdued emotional responses, and dull mental processes.
 Slow speech and enlarged tongue, hands, and feet.
 Constipation.
 Sleep apnea, pleural effusion, and pericardial effusion.
 ↑cholesterol level, atherosclerosis, coronary artery disease,
and poor left ventricular function.
 Intraoperative hypotension and postoperative heart failure may
occur to undiagnosed patients.
 Myxedema coma describes the most extreme, severe stage of
hypothyroidism, in which the patient is hypothermic and
unconscious.
 The patient would develop respiratory complications
culminating in coma.
 Cardiovascular collapse and shock. Mortality rate is high.

45. Hashimoto’s Disease
 Autoimmune disorder in which antibodies
are directed against a thyroid sites to :
Inhibit thyroid peroxidase(T4 –T3)
Inhibit effects of TSH
Stimulate thyroid growth
Lymphocytes are attracted to attacking thyroid
gland leading to inflammation and swelling

46. Hypothyroidism-Primary
 Drug induced
PTU & methimazole
 Iatrogenic
Surgical removal of the thyroid gland and
radiation treatment

47. Primary Hypothyroidism
 Thyroid gland failure
Decrease T3 & T4
Increase TRH inspite of negative feedback
Increased TSH due to decreased TRH

48. Secondary Hypothyroid
 Pituitary failure
Insufficient TSH release as a result of:
 Pituitary tumors
 Surgery
 Pituitary radiation
 Pituitary necrosis
 Autoimmune mechanisms

49. Tertiary Hypothyroidism
 Hypothalamic Failure- very rare
 Insufficient TRH release as a result of:
Trauma
Irradiation
Tumors

50. Hypothyroidism-Treatment
 Drug Therapy
 Levothyroxine Sodium-DOC synthetic T4
 Adults 1-1.5mcg/kg/day orally initially, adjust as
needed. Average dose 1.6-1.8mcg/kg/day
 Pediatrics 1-1.5mgc/kg/day. Average 4 mcg/kg/day

51. Hypothyroidism-Treatment
 Adverse Effects
MI
Osteopenia
HA
 Contraindicated
Acute MI
Treatment of obesity
Uncontrolled HTN

52. Monitoring
 Obtain baseline FT4, TSH, LFT, CBCs
before initiation of therapy
 Repeat FT4 and TSH after 4-6 weeks on
therapy and 4-6 weeks after adjustments
 Once euthyroid state obtain thyroid
function test after 3-6 months

53. Nursing Implications for Thyroid
tests
 Determine whether the patient has taken drugs or agents that contain
iodine. These include:
 Contrast agents (radiopaque, dye-like substances that may contain
iodine) and medications used to treat thyroid disorders.
 Topical antiseptics, multivitamin preparations, cough syrups; an
antiarrhythmic agent.
 Estrogens, salicylates, amphetamines (drugs that produce increased
wakefulness and focus ),chemotherapeutic agents, antibiotics, and
corticosteroids.
 Ask the patient about the use of these drugs and note their use on the
laboratory requisition.

54. Nursing Management
Modifying Activity
 The patient experiences decreased energy and
lethargy. As a result, the risk for complications from
immobility increases.
 The patient has decreased ability to exercise and
participate in activities due to changes in
cardiovascular and pulmonary status.
 The nurse’s role is to assist with care and hygiene
while encouraging the patient to participate in
activities as tolerated to prevent the complications of
immobility.

55. Modifying Activity
 The patient experiences decreased energy and
lethargy. As a result, the risk for complications
from immobility increases.
 The patient has decreased ability to exercise
and participate in activities due to changes in
cardiovascular and pulmonary status.
 The nurse’s role is to assist with care and
hygiene while encouraging the patient to
participate in activities as tolerated to prevent
the complications of immobility.

56. Monitoring Physical Status
 Close monitoring of the vital signs and cognitive level to
detect the following:
 Deterioration of physical and mental status
 Signs and symptoms indicating that treatment has resulted
in the metabolic rate exceeding the ability of the
cardiovascular and pulmonary systems to respond
 Continued limitations or complications of myxedema

57. Promoting Physical Comfort
 Extra clothing and blankets are provided.
 Use of heating pads and electric blankets is
avoided. This is because the patient could be
burned by these items without being aware of
it because of delayed responses and decreased
mental status.

58. Providing Emotional Support
 The patient may experience severe emotional
reactions. The nonspecific, early symptoms may
produce negative reactions by family members and
friends, who may have labeled the patient mentally
unstable, uncooperative, or unwilling to participate in
self-care activities.
 The nurse informs the patient and family that the
symptoms and inability to recognize them are
common but treatment is successful and symptoms
are reversible. The patient and family may require
assistance and counseling to deal with the emotional
concerns and reactions that result

59. Teaching Patients Self-Care
 The patient and family require information and
instruction that will enable them to monitor the
patient’s condition and response to therapy.
 The nurse instructs the patient and a family
member about medications.
 The nurse provides written instructions and
guidelines for the patient and family.
 Dietary instruction is provided to promote
weight loss once medication has been initiated.

60.  Before discharge, arrangements are made to ensure that the
patient returns to an environment that will promote adherence
to the prescribed treatment plan. The nurse:
 Assists in devising a schedule or record to ensure accurate
and complete administration of medications.
 Reinforces the importance of continued thyroid hormone
replacement and periodic follow-up testing and instructs
the patient and family members about the signs of
overmedication and undermedication.
 May refer the patient for home care.
 Documents and reports to the patient’s primary health care
provider, subtle signs and symptoms that may indicate
either inadequate or excessive thyroxine hormone.

61. THYROID DISORDERS IN PREGNANCY:
 TSH does
 decrease slightly in the first trimester. This
corresponds with increased beta HCG levels.
The
 changes in TSH levels may be explained by the
fact that beta HCG is not only structurally quite
 similar to TSH, but it also has thyrotropic activity.
It should also be noted that the thyroid gland
 itself may increase slightly in size during
pregnancy.

62. Hypothyroidism
 Significant hypothyroidism is unusual in pregnancy as
untreated hypothyroid patients rarely conceive and carry
a pregnancy. The few patients who do become pregnant
and remain untreated have an increased risk for
miscarriage, fetal loss, preeclampsia and low birth
weight.Treated hypothyroidism generally does not confer
an increased risk for pregnancy. check thyroid function
tests once per trimester. If this frequency of testing
shows that a patient requires an increase in thyroxine
replacement, we then consider checking the patient’s
thyroid function more frequently,there are individuals
who will require dose increases up to as high as 200
micrograms of levothyroxine per day. Patients should
also be instructed not to take their thyroid supplement at
the same time as their prenatal vitamins since iron can
decrease its absorption.

63.  Hyperthyroidism
The signs and symptoms of hyperthyroidism in
pregnancy are the same as they are for the
nonpregnant individual but the clinical diagnosis
is made more difficult by normal changes in
pregnancy which mimic hyperthyroidism. These
include increased heart rate, heat intolerance,
warm skin, and systolic flow murmurs. Findings
more suggestive of hyperthyroidism, however,
are tremor, weight loss, hyper defecation, thyroid
bruit, and eye findings consistent with Graves’
Disease.

64. Patients with good control are likely to have a good
pregnancy outcome. In contrast, patients with
untreated hyperthyroidism have decreased
fertility and an increased risk of miscarriage,
intrauterine growth retardation (IUGR),
premature labor,and perinatal mortality. Thyroid
storm can also occur in patients with poorly
controlled thyrotoxicosis especially at labor and
delivery. Thus the appropriate treatment of
hyperthyroidism in pregnancy is very important
for both maternal and fetal health.

65. To minimize fetal exposure to PTU and it’s
associated risk of fetal hypothyroidism and
fetal goiter, treatment favors use of lower
doses of medication which allow the
patient to be mildly hyperthyroid. Despite
improvement antepartum, Graves’
Disease often relapses after delivery and,
if needed, both beta blockers and PTU
can be used in nursing mothers.

66. Postpartum Thyroiditis
It frequently begins approximately 4 months postpartum
and usually starts with a period of acute inflammation
that manifests itself as a non-tender goiter associated
with hyperthyroidism. Over the course of time, the
hyperthyroidism is often followed by many months of
hypothyroidism. This hypothyroidism usually resolves
within a year following delivery. Antithyroid antibodies
are positive in 85% of the cases. At times it may become
important to distinguish postpartum thyroiditis from a
postpartum exacerbation of Graves’ disease. A
radioactive iodine uptake scan can easily make the
distinction as there will be little uptake in postpartum
thyroiditis.

67. Postpartum thyroiditis may
masquerade as postpartum depression
so it is essential to consider it in any
woman presenting with depressive
symptoms in the year after delivery.

68. Hyperemesis Gravidarum
In the majority of cases, it is felt that the hyperthyroidism is
caused by the hyperemesis itself. Beta HCG, the
placental hormone which is believed to be partially
responsible for the nausea and vomiting of hyperemesis,
is only one amino acid different from Thyroid Stimulating
Hormone (TSH). It is therefore believed that in some
cases of hyperemesis, the high levels of Beta HCG may
stimulate the thyroid. Hyperthyroidism associated with
hyperemesis usually resolves at the end of the first
trimester when the beta HCG levels start to decline and
the symptoms of hyperemesis tend to resolve.

69. Thyroid Nodules
new thyroid nodules always need to be
aggressively investigated in the gravid woman.
There appears to be a very high incidence of
malignancy in new thyroid nodules appearing
during pregnancy. Therefore, fine needle
aspirations should never be delayed because a
woman is pregnant. Despite the increased
incidence of malignancy in thyroid nodules
identified in pregnancy, pregnancy does not
have an adverse effect on the course of the
disease. Likewise, women with a history of
thyroid carcinoma who become pregnant do not
have a worsened prognosis overall.

70. Thyroid Investigations
The fetal thyroid avidly binds iodine starting at 10-12 weeks
gestation so that administering radioactive iodine to
pregnant women results in doses to the fetus which are
much greater than the exposure to the mother. It should
be completely avoided in pregnancy. Nursing mothers
who have radioactive iodine scans should be counseled
to pump and discard their milk for 48-72 hours before
resuming breastfeeding. If needed, thyroid ultrasounds
and fine needle aspirations may be done safely in the
pregnant woman.