toxic goiter

1. INTERNATIONAL SCHOOL OFINTERNATIONAL SCHOOL OF
MEDICINEMEDICINE
PPT OF TOXIC NODULARPPT OF TOXIC NODULAR
GOITERGOITER
NAME JYOTI DAHIYANAME JYOTI DAHIYA
GROUP 21GROUP 21stst
SEMESTER 7SEMESTER 7thth

2. Surgical Anatomy of thyroid glandSurgical Anatomy of thyroid gland
 The thyroid gland has two lobes the right and the left.The thyroid gland has two lobes the right and the left.
These lobes are connected in the midline by a sleeve ofThese lobes are connected in the midline by a sleeve of
thyroid tissue known as the isthmus. The whole gland isthyroid tissue known as the isthmus. The whole gland is
covered anteriorly by infrahyoid group of muscles.covered anteriorly by infrahyoid group of muscles.
 Major blood supply to thyroid gland arises from the superiorMajor blood supply to thyroid gland arises from the superior
thyroid artery a branch of the external carotid artery, and inferiorthyroid artery a branch of the external carotid artery, and inferior
thyroid artery by way of the thyrocervical trunk. Venous supplythyroid artery by way of the thyrocervical trunk. Venous supply
accompanies the arteries. A middle thyroid vein directly drains intoaccompanies the arteries. A middle thyroid vein directly drains into
the internal jugular vein.the internal jugular vein.

3. anatomyanatomy

4. Nerve relationship to thyroid glandNerve relationship to thyroid gland
 Recurrent laryngeal nerves and their relationship to the thyroidRecurrent laryngeal nerves and their relationship to the thyroid
gland: The recurrent laryngeal nerve innervate the intrinsicgland: The recurrent laryngeal nerve innervate the intrinsic
muscles of larynx. It also provides sensory innervation to themuscles of larynx. It also provides sensory innervation to the
glottis. The recurrent laryngeal nerve arises from the vagus atglottis. The recurrent laryngeal nerve arises from the vagus at
the level of subclavian artery on the right side and at the levelthe level of subclavian artery on the right side and at the level
of the aortic arch on the left. The nerves then turn superioof the aortic arch on the left. The nerves then turn superio
medially and runs towards the tracheo oesophageal groove. Asmedially and runs towards the tracheo oesophageal groove. As
the recurrent laryngeal nerve ascends the tracheo oesophagealthe recurrent laryngeal nerve ascends the tracheo oesophageal
groove it is intimately related to the inferior thyroid artery. Thegroove it is intimately related to the inferior thyroid artery. The
nerves may pass superficial or deep between the branches ofnerves may pass superficial or deep between the branches of
the inferior thyroid artery.the inferior thyroid artery.
The recurrent laryngeal nerve as it travels in the tracheo oesophageal
groove, it comes into intimate contact with the posterior portion of the
thyroid gland.
It is always better to identify the nerve at the level of cricothryoid joint, at
which point it enters the larynx. Injury to this nerve should be prevented
during surgery at all costs, as this will cause vocal cord paralysis. Damage
to recurrent laryngeal nerves on both sides will cause stridor necessitating
tracheostomy due to bilateral abductor palsy.
Non recurrent laryngeal nerve: arises directly from the cervical portion of
the vagus at about the level of the larynx and enters it at the level of the
cricopharyngeal joint. Majority of these nerves occur on the right side and
is commonly associated with an anomalous retro esophageal subclavian
artery.

6. Nerve relationshipNerve relationship
 Superior laryngeal nerve: arise from the inferior vagal ganglion (nodose)Superior laryngeal nerve: arise from the inferior vagal ganglion (nodose)
and descend inferiorly deep to the carotid system. As the superiorand descend inferiorly deep to the carotid system. As the superior
laryngeal nerve descends towards the thyrohyoid membrane they passlaryngeal nerve descends towards the thyrohyoid membrane they pass
anterior to the cervical sympathetic trunk and posterior to the carotidanterior to the cervical sympathetic trunk and posterior to the carotid
system. Friedman proposed a classification to account for the anatomicsystem. Friedman proposed a classification to account for the anatomic
variations of superior laryngeal nerve. They are:variations of superior laryngeal nerve. They are:
Type I: The nerve runs superficial to the inferior constrictor muscle.Type I: The nerve runs superficial to the inferior constrictor muscle.
Type II: The nerve penetrates the lower part of the inferior constrictorType II: The nerve penetrates the lower part of the inferior constrictor
muscle.muscle.
Type III: The nerve penetrates the superior part of the inferior constrictorType III: The nerve penetrates the superior part of the inferior constrictor
muscle. muscle.
The superior laryngeal nerve travels in close proximity to the superiorThe superior laryngeal nerve travels in close proximity to the superior
thyroid artery. This nerve should be protected by the surgeon at allthyroid artery. This nerve should be protected by the surgeon at all
costs.costs.
Injury to this nerve will cause minor degrees of voice change since thisInjury to this nerve will cause minor degrees of voice change since this
nerve supply the cricothyroid muscle. It patient will not be able to raisenerve supply the cricothyroid muscle. It patient will not be able to raise
the pitch of his voice. This becomes really troublesome for a singer. Itthe pitch of his voice. This becomes really troublesome for a singer. It
also supplies sensory innervation to larynx. also supplies sensory innervation to larynx.
Parathyroid glands: During surgery every effort should be made toParathyroid glands: During surgery every effort should be made to
identify and preserve the parathyroid glands. These glands are 4 inidentify and preserve the parathyroid glands. These glands are 4 in
number. The superior parathyroids embryologically arise from the 4thnumber. The superior parathyroids embryologically arise from the 4th
pouch, while the inferior parathyroids arise from the 3rd pouch. Thepouch, while the inferior parathyroids arise from the 3rd pouch. The
superior parathyroid glands lies near the cricothryoid joint, at thesuperior parathyroid glands lies near the cricothryoid joint, at the
intersection between the recurrent laryngeal nerve and the inferiorintersection between the recurrent laryngeal nerve and the inferior
thyroid artery. The inferior parathyroids are variable in position becausethyroid artery. The inferior parathyroids are variable in position because
it has to migrate long distances due to the position of the thymus gland.it has to migrate long distances due to the position of the thymus gland.
Commonly they are located close to the inferior thyroid pole. TheCommonly they are located close to the inferior thyroid pole. The
parathyroid glands are supplied by branches from the inferior thyroidparathyroid glands are supplied by branches from the inferior thyroid
artery, hence it should be protected.artery, hence it should be protected.

7. Toxic goiterToxic goiter
Toxic multinodular goiterToxic multinodular goiter (also known as (also known as toxic nodulartoxic nodular
goitergoiter, , toxic nodular strumatoxic nodular struma , or , or Plummer's diseasePlummer's disease ) is a ) is a
multinodular goitermultinodular goiter associated with a associated with a hyperthyroidismhyperthyroidism..
It is a common cause of hyperthyroidism in which there is excessIt is a common cause of hyperthyroidism in which there is excess
production of production of thyroid hormonesthyroid hormones from functionally autonomous thyroid from functionally autonomous thyroid
nodules, which do not require stimulation from nodules, which do not require stimulation from
thyroid stimulating hormonethyroid stimulating hormone (TSH) (TSH)
Toxic multinodular goiter is the second most common cause ofToxic multinodular goiter is the second most common cause of
hyperthyroidism (after hyperthyroidism (after Graves' diseaseGraves' disease) in the developed world,) in the developed world,
whereas iodine deficiency is the most common cause of whereas iodine deficiency is the most common cause of
hypothyroidismhypothyroidism in developing-world countries where the population is in developing-world countries where the population is
iodine-deficient. (Decreased iodine leads to decreased thyroidiodine-deficient. (Decreased iodine leads to decreased thyroid
hormone.) However, iodine deficiency can cause goitre (thyroidhormone.) However, iodine deficiency can cause goitre (thyroid
enlargement); within a goitre, nodules can develop. Risk factors forenlargement); within a goitre, nodules can develop. Risk factors for
toxic multinodular goiter include individuals over 60 years of age andtoxic multinodular goiter include individuals over 60 years of age and
being female.being female.

9. Causes or etiologyCauses or etiology
 Functional autonomy of the thyroid gland appears to be related toFunctional autonomy of the thyroid gland appears to be related to
iodine deficiency. Various mechanisms have been implicated, butiodine deficiency. Various mechanisms have been implicated, but
the molecular pathogenesis is poorly understood.the molecular pathogenesis is poorly understood.
 The sequence of events leading to toxic multinodular goiter is asThe sequence of events leading to toxic multinodular goiter is as
follows:follows:
 Iodine deficiency leads to low levels of T4; this induces thyroid cellIodine deficiency leads to low levels of T4; this induces thyroid cell
hyperplasia to compensate for the low levels of T4.hyperplasia to compensate for the low levels of T4.
 Increased thyroid cell replication predisposes single cells to somaticIncreased thyroid cell replication predisposes single cells to somatic
mutations of the TSH receptor. Constitutive activation of the TSHmutations of the TSH receptor. Constitutive activation of the TSH
receptor may generate autocrine factors that promote furtherreceptor may generate autocrine factors that promote further
growth, resulting in clonal proliferation. Cell clones then producegrowth, resulting in clonal proliferation. Cell clones then produce
multiple nodules.multiple nodules.
 Somatic mutations of the TSH receptors and G α protein conferSomatic mutations of the TSH receptors and G α protein confer
constitutive activation to the cyclic adenosine monophosphateconstitutive activation to the cyclic adenosine monophosphate
(cAMP) cascade of the inositol phosphate pathways. These(cAMP) cascade of the inositol phosphate pathways. These
mutations may be responsible for functional autonomy of the thyroidmutations may be responsible for functional autonomy of the thyroid
in 20-80% of cases. [1]in 20-80% of cases. [1]
 These mutations are found in autonomously functioning thyroidThese mutations are found in autonomously functioning thyroid
nodules, solitary and within a multinodular gland. Nonfunctioningnodules, solitary and within a multinodular gland. Nonfunctioning
thyroid nodules within the same gland lack these mutations.thyroid nodules within the same gland lack these mutations.

11. Sign and symptomsSign and symptoms Thyrotoxic symptoms - Most patients with toxic nodular goiter (TNG) presentThyrotoxic symptoms - Most patients with toxic nodular goiter (TNG) present
with symptoms typical of hyperthyroidism, including heat intolerance,with symptoms typical of hyperthyroidism, including heat intolerance,
palpitations, tremor, weight loss, hunger, and frequent bowel movements.palpitations, tremor, weight loss, hunger, and frequent bowel movements.
 Elderly patients may have more atypical symptoms, including the following:Elderly patients may have more atypical symptoms, including the following:
– Weight loss is the most common complaint in elderly patients withWeight loss is the most common complaint in elderly patients with
hyperthyroidism.hyperthyroidism.
– Anorexia and constipation may occur, in contrast to frequent bowelAnorexia and constipation may occur, in contrast to frequent bowel
movements often reported by younger patients.movements often reported by younger patients.
– Dyspnea or palpitations may be a common occurrence.Dyspnea or palpitations may be a common occurrence.
– Tremor also occurs but can be confused with essential senile tremor.Tremor also occurs but can be confused with essential senile tremor.
– Cardiovascular complications occur commonly in elderly patients, and aCardiovascular complications occur commonly in elderly patients, and a
history of atrial fibrillation, congestive heart failure, or angina may behistory of atrial fibrillation, congestive heart failure, or angina may be
present.present.
 Obstructive symptoms - A significantly enlarged goiter can cause symptomsObstructive symptoms - A significantly enlarged goiter can cause symptoms
related to mechanical obstruction.related to mechanical obstruction.
 A large substernal goiter may cause dysphagia, dyspnea, or frank stridor.A large substernal goiter may cause dysphagia, dyspnea, or frank stridor.
Rarely, this goiter results in a surgical emergency.Rarely, this goiter results in a surgical emergency.
 Involvement of the recurrent or superior laryngeal nerve may result inInvolvement of the recurrent or superior laryngeal nerve may result in
complaints of hoarseness or voice change.complaints of hoarseness or voice change.
 Asymptomatic - Many patients are asymptomatic or have minimal symptomsAsymptomatic - Many patients are asymptomatic or have minimal symptoms
and are incidentally found to have hyperthyroidism during routine screening.and are incidentally found to have hyperthyroidism during routine screening.
The most common laboratory finding is a suppressed TSH with normal freeThe most common laboratory finding is a suppressed TSH with normal free
thyroxine (T4) levels.thyroxine (T4) levels.

13. Physical examinationPhysical examination
 Findings of hyperthyroidism may be more subtle than thoseFindings of hyperthyroidism may be more subtle than those
of Graves disease. Features may include widened,of Graves disease. Features may include widened,
palpebral fissures; tachycardia; hyperkinesis; moist, smoothpalpebral fissures; tachycardia; hyperkinesis; moist, smooth
skin; tremor; proximal muscle weakness; and brisk deepskin; tremor; proximal muscle weakness; and brisk deep
tendon reflexes.tendon reflexes.
 The size of the thyroid gland is variable. Large substernalThe size of the thyroid gland is variable. Large substernal
glands may not be appreciable upon physical examination.glands may not be appreciable upon physical examination.
 A dominant nodule or multiple irregular, variably sizedA dominant nodule or multiple irregular, variably sized
nodules are typically present. In a small gland,nodules are typically present. In a small gland,
multinodularity may be apparent only on an ultrasonogram.multinodularity may be apparent only on an ultrasonogram.
Chronic Graves disease may present with some nodularity;Chronic Graves disease may present with some nodularity;
therefore, establishing the diagnosis is sometimes difficult.therefore, establishing the diagnosis is sometimes difficult.
 Hoarseness or tracheal deviation may be present uponHoarseness or tracheal deviation may be present upon
examination.examination.
 Mechanical obstruction may result in superior vena cavaMechanical obstruction may result in superior vena cava
syndrome, with engorgement of facial and neck veinssyndrome, with engorgement of facial and neck veins
(Pemberton sign). [4](Pemberton sign). [4]
 Stigmata of Graves disease (eg, orbitopathy, pretibialStigmata of Graves disease (eg, orbitopathy, pretibial
myxedema, acropachy) are not observed.myxedema, acropachy) are not observed.

15. Pathophysiology to toxic nodular goiterPathophysiology to toxic nodular goiter
 PathophysiologyPathophysiology
 Toxic nodular goiterToxic nodular goiter (TNG) represents a spectrum of (TNG) represents a spectrum of
disease ranging from a single hyperfunctioning noduledisease ranging from a single hyperfunctioning nodule
(toxic adenoma) within a multinodular thyroid to a gland(toxic adenoma) within a multinodular thyroid to a gland
with multiple areas of hyperfunction. The natural historywith multiple areas of hyperfunction. The natural history
of a multinodular goiter involves variable growth ofof a multinodular goiter involves variable growth of
individual nodules; this may progress to hemorrhage andindividual nodules; this may progress to hemorrhage and
degeneration, followed by healing and fibrosis.degeneration, followed by healing and fibrosis.
Calcification may be found in areas of previousCalcification may be found in areas of previous
hemorrhage. Some nodules may develop autonomoushemorrhage. Some nodules may develop autonomous
function. Autonomous hyperactivity is conferred byfunction. Autonomous hyperactivity is conferred by
somatic mutations of the thyrotropin, or thyroid-somatic mutations of the thyrotropin, or thyroid-
stimulating hormone (TSH), receptor in 20-80% of toxicstimulating hormone (TSH), receptor in 20-80% of toxic
adenomas and some nodules of multinodularadenomas and some nodules of multinodular
goiters. [1] Autonomously functioning nodules maygoiters. [1] Autonomously functioning nodules may
become toxic in 10% of patients. Hyperthyroidismbecome toxic in 10% of patients. Hyperthyroidism
predominantly occurs when single nodules are largerpredominantly occurs when single nodules are larger
than 2.5 cm in diameter. Signs and symptoms of TNGthan 2.5 cm in diameter. Signs and symptoms of TNG
are similar to those of other types of hyperthyroidism.are similar to those of other types of hyperthyroidism.

16. epidemiologyepidemiology
 FrequencyFrequency
 United StatesUnited States
 Toxic nodular goiter accounts for approximately 15-30% of cases ofToxic nodular goiter accounts for approximately 15-30% of cases of
hyperthyroidism in the United States, second only to Graveshyperthyroidism in the United States, second only to Graves
disease.disease.
 InternationalInternational
 In areas of endemic iodine deficiency, In areas of endemic iodine deficiency, toxic nodular goitertoxic nodular goiter (TNG) (TNG)
accounts for approximately 58% of cases of hyperthyroidism, 10%accounts for approximately 58% of cases of hyperthyroidism, 10%
of which are from solitary toxic nodules. Graves disease accountsof which are from solitary toxic nodules. Graves disease accounts
for 40% of cases of hyperthyroidism. In patients with underlyingfor 40% of cases of hyperthyroidism. In patients with underlying
nontoxic multinodular goiter, initial iodine supplementation (ornontoxic multinodular goiter, initial iodine supplementation (or
iodinated contrast agents) can lead to hyperthyroidism (Jod-iodinated contrast agents) can lead to hyperthyroidism (Jod-
Basedow effect). Iodinated drugs, such as amiodarone, may alsoBasedow effect). Iodinated drugs, such as amiodarone, may also
induce hyperthyroidism in patients with underlying nontoxicinduce hyperthyroidism in patients with underlying nontoxic
multinodular goiter. Roughly 3% of patients treated with amiodaronemultinodular goiter. Roughly 3% of patients treated with amiodarone
in the United States (more in areas of iodine deficiency) developin the United States (more in areas of iodine deficiency) develop
amiodarone-induced hyperthyroidism. [amiodarone-induced hyperthyroidism. [

17. Mortality/MorbidityMortality/Morbidity
 Morbidity and mortality from toxic nodular goiter (TNG)Morbidity and mortality from toxic nodular goiter (TNG)
may be divided into problems related to hyperthyroidismmay be divided into problems related to hyperthyroidism
and problems related to growth of the nodules andand problems related to growth of the nodules and
gland. Local compression problems due to nodulegland. Local compression problems due to nodule
growth, although unusual, include dyspnea, hoarseness,growth, although unusual, include dyspnea, hoarseness,
and dysphagia. Both TNG and Graves disease haveand dysphagia. Both TNG and Graves disease have
increased mortality but for different reasons. [3]increased mortality but for different reasons. [3]
 TNG is more common in elderly adults; therefore,TNG is more common in elderly adults; therefore,
complications due to comorbidities, such as coronarycomplications due to comorbidities, such as coronary
artery disease, are significant in the management ofartery disease, are significant in the management of
hyperthyroidism.hyperthyroidism.
 SexSex
 Toxic nodular goiter occurs more commonly in womenToxic nodular goiter occurs more commonly in women
than in men. In women and men older than 40 years, thethan in men. In women and men older than 40 years, the
prevalence rate of palpable nodules is 5-7% and 1-2%,prevalence rate of palpable nodules is 5-7% and 1-2%,
respectively.respectively.
 AgeAge
 Most patients with toxic nodular goiter (TNG) are olderMost patients with toxic nodular goiter (TNG) are older
than 50 years.than 50 years.

18. Laboratory studiesLaboratory studies
 Thyroid function tests [7] - Evidence of hyperthyroidism must beThyroid function tests [7] - Evidence of hyperthyroidism must be
present in order to consider a diagnosis of toxic nodular goiterpresent in order to consider a diagnosis of toxic nodular goiter
(TNG).(TNG).
 See the list below:See the list below:
 Third-generation TSH assays are generally the best initial screeningThird-generation TSH assays are generally the best initial screening
tool for hyperthyroidism. Patients with TNG will have suppressedtool for hyperthyroidism. Patients with TNG will have suppressed
TSH levels.TSH levels.
 Free T4 levels or surrogates of free T4 levels (ie, free T4 index) mayFree T4 levels or surrogates of free T4 levels (ie, free T4 index) may
be elevated or within the reference range. An isolated increase in T4be elevated or within the reference range. An isolated increase in T4
is observed in iodine-induced hyperthyroidism or in the presence ofis observed in iodine-induced hyperthyroidism or in the presence of
agents that reduce peripheral conversion of T4 to triiodothyronineagents that reduce peripheral conversion of T4 to triiodothyronine
(T3) (eg, propranolol, corticosteroids, radiocontrast agents,(T3) (eg, propranolol, corticosteroids, radiocontrast agents,
amiodarone).amiodarone).
 Some patients may have normal free T4 levels (or free T4 index)Some patients may have normal free T4 levels (or free T4 index)
with an elevated T3 level (T3 toxicosis); this may occur in 5-46% ofwith an elevated T3 level (T3 toxicosis); this may occur in 5-46% of
patients with toxic nodules. Note that the total T3 and T4 levels maypatients with toxic nodules. Note that the total T3 and T4 levels may
often be within the reference range but may be higher than theoften be within the reference range but may be higher than the
normal range for a particular individual; this is especially true innormal range for a particular individual; this is especially true in
patients with nonthyroidal illness in which T3 levels are decreased.patients with nonthyroidal illness in which T3 levels are decreased.
 Subclinical hyperthyroidism - Some patients may have suppressedSubclinical hyperthyroidism - Some patients may have suppressed
TSH levels with normal free T4 and total T3 levels.TSH levels with normal free T4 and total T3 levels.

19. Imaging studiesImaging studies
 Nuclear scintigraphy [7]Nuclear scintigraphy [7]
 Nuclear scans should be performed on patients with biochemical hyperthyroidism.Nuclear scans should be performed on patients with biochemical hyperthyroidism.
Nuclear medicine scans can be performed with radioactive iodine-123 ( 123 I) or withNuclear medicine scans can be performed with radioactive iodine-123 ( 123 I) or with
technetium-99m ( 99m Tc). These isotopes are chosen for their shorter half-life andtechnetium-99m ( 99m Tc). These isotopes are chosen for their shorter half-life and
because they provide lower radiation exposure to the patient when compared withbecause they provide lower radiation exposure to the patient when compared with
sodium iodide-131 (Na 131 I).sodium iodide-131 (Na 131 I).
 99m Tc is trapped in the thyroid but is not organified. Although convenient,99m Tc99m Tc is trapped in the thyroid but is not organified. Although convenient,99m Tc
scanning may provide misleading results. Some nodules that appear hot or warmscanning may provide misleading results. Some nodules that appear hot or warm
on 99m TC scan results may be cold on 123 I scan results. Nodules withon 99m TC scan results may be cold on 123 I scan results. Nodules with
discordant 99m Tc and 123 I scan results may be malignant; therefore, 123 Idiscordant 99m Tc and 123 I scan results may be malignant; therefore, 123 I
scanning is preferred.scanning is preferred.
 Nuclear scans allow determination of the cause of hyperthyroidism. Patients withNuclear scans allow determination of the cause of hyperthyroidism. Patients with
Graves disease usually have homogeneous diffuse uptake. Glands with thyroiditisGraves disease usually have homogeneous diffuse uptake. Glands with thyroiditis
have low uptake.have low uptake.
 In patients with toxic nodular goiter (TNG), the scan results usually reveal patchyIn patients with toxic nodular goiter (TNG), the scan results usually reveal patchy
uptake (see the image below), with areas of increased and decreased uptake. Theuptake (see the image below), with areas of increased and decreased uptake. The
uptake rate of radioiodine in 24 hours averages approximately 20-30%. Radioactiveuptake rate of radioiodine in 24 hours averages approximately 20-30%. Radioactive
Na 131 I ablation of the thyroid gland may be considered if the thyroid uptake value isNa 131 I ablation of the thyroid gland may be considered if the thyroid uptake value is
elevated. Several therapeutic modalities have been suggested to increase uptakeelevated. Several therapeutic modalities have been suggested to increase uptake
(eg, low iodine diet, lithium, recombinant TSH, propylthiouracil(eg, low iodine diet, lithium, recombinant TSH, propylthiouracil
 UltrasoundUltrasound
 MRIMRI
 CT SCANCT SCAN

20. treatmenttreatment
 Antithyroid agents(Propylthiouracil, Methimazole (Tapazole))Antithyroid agents(Propylthiouracil, Methimazole (Tapazole))
 Beta-adrenergic receptor antagonistsBeta-adrenergic receptor antagonists (Propranolol, a nonselective(Propranolol, a nonselective
beta blocker, may help to lower the heart rate, control tremor,beta blocker, may help to lower the heart rate, control tremor,
reduce excessive sweating, and alleviate anxiety. Propranolol isreduce excessive sweating, and alleviate anxiety. Propranolol is
also known to reduce the conversion of T4 to T3.In patients withalso known to reduce the conversion of T4 to T3.In patients with
underlying asthma, beta-1 selective antagonists, such as atenolol orunderlying asthma, beta-1 selective antagonists, such as atenolol or
metoprolol, would be safer options.metoprolol, would be safer options.
In patients with contraindications to beta blockers (eg, moderate toIn patients with contraindications to beta blockers (eg, moderate to
severe asthma), calcium channel antagonists (eg, diltiazem) may besevere asthma), calcium channel antagonists (eg, diltiazem) may be
used to help control the heart rateused to help control the heart rate
 Radioactive iodines (Radioactive iodines (Sodium iodide-131 (Na131Sodium iodide-131 (Na131 I;I; Iodotope)Iodotope)
Used to treat hyperthyroidism by destroying follicular cells of the thyroidUsed to treat hyperthyroidism by destroying follicular cells of the thyroid
gland. The dose is determined by radioactivity calibration systemgland. The dose is determined by radioactivity calibration system
just prior to administration.just prior to administration.

21. Surgical careSurgical care
 Surgical therapy is usually reserved for young individuals, patients with 1 orSurgical therapy is usually reserved for young individuals, patients with 1 or
more large nodules or with obstructive symptoms, patients with dominantmore large nodules or with obstructive symptoms, patients with dominant
nonfunctioning or suspicious nodules, patients who are pregnant, patients innonfunctioning or suspicious nodules, patients who are pregnant, patients in
whom radioiodine therapy has failed, or patients who require a rapidwhom radioiodine therapy has failed, or patients who require a rapid
resolution of the thyrotoxic state.resolution of the thyrotoxic state.
 Total or near-total thyroidectomy results in rapid cure of hyperthyroidism inTotal or near-total thyroidectomy results in rapid cure of hyperthyroidism in
90% of patients and allows for rapid relief of compressive90% of patients and allows for rapid relief of compressive
symptoms. [21] Goiter recurrence is lower patients who undergo total orsymptoms. [21] Goiter recurrence is lower patients who undergo total or
near-total thyroidectomy compared to subtotal thyroidectomy. [22]near-total thyroidectomy compared to subtotal thyroidectomy. [22]
 Restoring euthyroidism prior to surgery is preferable.Restoring euthyroidism prior to surgery is preferable.
 Complications of surgery include the following:Complications of surgery include the following:
 In patients who are treated surgically, the frequency of hypothyroidism isIn patients who are treated surgically, the frequency of hypothyroidism is
similar to that found in patients treated with radioiodine (15-25%), and issimilar to that found in patients treated with radioiodine (15-25%), and is
strongly dependent on the extent of the surgery.strongly dependent on the extent of the surgery.
 Complications include permanent vocal cord paralysis (2.3%), permanentComplications include permanent vocal cord paralysis (2.3%), permanent
hypoparathyroidism (0.5%), temporary hypoparathyroidism (2.5%), andhypoparathyroidism (0.5%), temporary hypoparathyroidism (2.5%), and
significant postoperative bleeding (1.4%).significant postoperative bleeding (1.4%).
 Other postoperative complications include tracheostomy, wound infection,Other postoperative complications include tracheostomy, wound infection,
wound hematoma, myocardial infarction, atrial fibrillation, and stroke.wound hematoma, myocardial infarction, atrial fibrillation, and stroke.
 In experienced hands the mortality rate is almost zero.In experienced hands the mortality rate is almost zero.
 When radioactive iodine, surgery or long-term antithyroidal drugs areWhen radioactive iodine, surgery or long-term antithyroidal drugs are
inappropriate or contraindicated, radiofrequency ablation can be consideredinappropriate or contraindicated, radiofrequency ablation can be considered
in select patients. in select patients.