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15 Surgery ofParathyroid Glands
Fig. 15.2 CT/MIBI
image of enlarged
parathyroid in left upper
position
445
15.7 Treatment
15.7.1 When toOperate andWhat
Benets toExpect?
Causal links between hyperparathyroidism and
its harmful effects are well established in large
populations but asserting whether there is such a
link in each individual case could be difcult.
There is general consensus that symptomatic
patients presenting with end-organ damage such
as renal stones, severe osteoporosis, or pancreatitis should be offered surgery, both on account of
seriousness of presentation and consequences of
not treating it. The decision to operate is more
complex when faced with uncertainty whether
subtler symptoms such as fatigue or depression
are caused by PHPT or in 80% of patients who
declare no symptoms at all.
When deciding whether to operate, surgeon
should take into account existing Guidelines, evidence from Observational Studies and
Randomized Controlled Trials (RCTs). Regularly
updated NIH Guidelines advice surgery in
asymptomatic patients younger than 50 years,
when calcium level is >0.25mmol/L above upper
limits of normal, creatinine clearance GFR
reduced to <60mL/min, or bone mineral density
T score ≤ −2.5 at any site. Evidence from
Observational Studies suggests that even subtle
abnormalities of calcium and PTH levels are
associated with adverse health outcomes.
Between 1/4 and 1/3 of patients with asymptomatic PHPT left untreated for 10–15years develop
progressive disease with worsening hypercalcemia, hypercalcuria and reduced bone density.
Patients younger than 50 years have increased
risk of disease progression. Patients who had
parathyroidectomy had signicant improvement
in BMD at hip and lumbar spine but not forearm.
Patients with untreated PHPT have increased
mortality predominantly from CVD, but in
patients who had surgery there was decline in
mortality. Another study of patients with PHPT
showed increased standardized morbidity and
mortality for coronary and cerebrovascular diseases and cancer such as colon, kidney, and
breast. Dyslipidemia and diabetes are more prevalent in patients with PHPT.
Evidence from RCTs informs us that surgery
reduces formation of renal stones, improves
BDM and reduces fractures. Although parathy-
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446
T. R. Kurzawinski
roidectomy improves dyslipidemia, no overall
improvement in cardiovascular events or
decreased mortality has been observed. Impact of
surgery on quality of life and neuropsychological
outcomes is uncertain, as results of studies are
contradictory.
15.7.2 Surgery
The aims of surgery in patients with PHPT are
immediate and permanent cure of abnormally
high levels of calcium and PTH, alleviation of the
symptoms, and prevention or reversal of endorgan damage. The choice of operating technique, which includes Bilateral Neck Exploration
(BNE) or Minimally Invasive Parathyroidectomy
(MIP), depends on underlying parathyroid
pathology and imaging results indicating the
number and location of glands to be removed. In
patients who need removal of 1–3 abnormal
glands, normalization of calcium and PTH levels
without postoperative supplementation is the
goal. When all 4 glands are abnormal and have to
be removed, the goal is normo-calcemia maintained either by calcium and Vitamin D3
supplementation or auto-transplantation of parathyroid tissue.
15.7.2.1 Bilateral Neck Exploration
(BNE)
Bilateral neck exploration (BNE) with visualization of all four parathyroid glands, irrespective of
the underlying parathyroid pathology, has been
the gold standard surgical treatment for many
past decades [15]. It is effective and safe procedure, able to cure 95% of patients with sporadic
and 80–90% of patients with familial
PHPT. Typically, BNE is performed through a
collar incision with exposure and dissection of all
the parathyroid glands prior to deciding which
glands should be removed. It allows not only
direct visualization of four glands but also enable
exploration of sites of potential ectopic glands.
Decisions that glands are abnormal and need
removing are based on prior knowledge of preoperative imaging and the size of the glands
observed during surgery. BNE remains the opera-
tion of choice in three distinct scenarios: rst, in
familial PHPT when multiple glands are expected
to be abnormal, second, when all imaging is negative and third, when MIP fails to identify the
enlarged gland and thereby conversion to BNE is
necessary. Complication rate after parathyroidectomy is not well quantied but expected to be
below 4% with bleeding and infection accounting for 1% and transient or permanent laryngeal
nerve injury for 2–3%.
In patients with familial HPT, extend of parathyroidectomy depends on underlying pathology.
In MEN1, four glands parathyroidectomy is often
recommended as subtotal (less than four glands)
parathyroidectomy is associated with high rates
of recurrence requiring further surgery.
Sometimes the decision is taken to remove 3 or
3½ parathyroids achieving immediate cure and
accepting high risk of recurrence. In MEN2a,
where frequently single gland is involved,
removal of 1–3 glands can be curative without
the risk of permanent hypocalcaemia. As the risk
of PHPT in MEN2a is relatively low (10%), parathyroids removed incidentally during prophylactic thyroidectomy should be reimplanted into
muscle. HPT JT syndrome has a 15% risk of
parathyroid carcinoma and surgical options
include the removal of the single abnormal gland
with subsequent annual surveillance of calcium
and parathyroid hormone levels [34] or prophylactic total parathyroidectomy to prevent future
malignancy or recurrent HPT. FIHPT is a complex disease associated with mutations in different genes including CaSR, MEN1, and HRPT2.
The current recommendation is to remove 1–4
abnormal glands using intraoperative PTH and
consider auto transplantation. In neonates with
NSHPT, four glands parathyroidectomy is essential to achieve cure and in our experience removal
of less than four glands results in persistently
high levels of calcium and PTH.
Parathyroid auto-transplantation is frequently
considered when multiple parathyroid glands are
removed. First described in 1926, it is a common
and established practice when normal parathyroids are incidentally removed during thyroidectomy. Auto-transplanting abnormal parathyroid
tissue is controversial and presents a dilemma. It
t.me/Dr_Mouayyad_AlbtousH
15 Surgery ofParathyroid Glands
447
is potentially desirable, since there is no direct
hormonal replacement therapy available for the
parathyroid hormone, and the medical management of postoperative hypoparathyroidism
requires vitamin D and calcium supplementation.
However, transplanted abnormal parathyroid tissue could cause recurrence requiring more surgery. If auto-transplantation is pursued, it can be
carried out either during the primary procedure
or after cold storage (cryopreservation in
−135°C) usually within 24months. The excised
gland is divided to multiple small pieces and
placed in the sternocleidomastoid or forearm
muscles. Alternative procedure involves intramuscular injections of parathyroid glands. Good
graft function has been reported in 86–100% of
adult patients [16].
15.7.2.2 Minimally Invasive
Parathyroidectomy (MIP)
Minimally Invasive Parathyroidectomy (MIP)
was introduced 2 decades ago and represents a
signicant development in surgical management
of PHPT.Growing acceptance of MIP as a procedure of choice is due to realization that solitary
adenomas are responsible for majority of cases of
sporadic HPT [17]. Improved accuracy of preoperative imaging allows precise localization of the
adenoma and enables its targeted removal, without the need for dissection of remaining parathyroid glands. Majority of patients could be now
selected for MIP and benet from the surgery
performed through smaller incisions, better scars,
less pain, and reduced hospital stay.
There are two distinctive techniques employed
to perform MIP.First is a mini-incision parathy-
roidectomy, which usually involves a 1inch or
smaller lateral incision overlying the affected
parathyroid gland [18]. Dissection is carried out
between sternomastoid and strap muscles toward
lateral border of thyroid, which is retracted medially and upward with retractors. Blunt dissection
allows direct visualization of enlarged parathyroid and important landmarks such as carotid,
inferior thyroid artery, and recurrent laryngeal
nerve. If enlarged gland is not found in position
indicated by preoperative localization, dissection
could be carried toward upper or lower pole
through the same incision. If the abnormal gland
is on the opposite side, incision is extended horizontally across midline and BNE is performed.
The advantage of this technique is its simplicity,
speed, and no need for special equipment [19,
20]. Second is endoscopic, also known as video-
assisted parathyroidectomy. Endoscope is introduced either in the midline, laterally between the
carotid sheath and the strap muscles or via a
trans-axillary approach. Space is created either
by insufation of carbon dioxide or gasless
retraction and instruments are introduced through
the same or separate incisions. Disadvantage of
this approach is requirement for videoscopic
equipment and increase in operating time [21].
Robotic parathyroidectomy using trans-axillary
approach keeps the scar away from neck, but its
cost is unnecessary high, and it is unlikely to
become commonly used. MIP, irrespective of
technique employed, can cure as many as 98% of
patients with sporadic PHPT, a success rate is
similar to BNE.
15.7.2.3 Intra-operative Techniques
Aiding Localization
andConrmation ofCure
Failure of surgery to cure HPT (5–10%) is predominantly due to either multigland disease
(hyperplasia, double adenomas) unrecognized by
preoperative localization studies, or the inability
to nd parathyroid glands in unusual locations
(ectopic glands). Various operative adjuncts are
commonly used to overcome these problems and
improve cure rate.
Frozen section of resected specimens is the
oldest and most widely used technique to conrm
that removed tissue is a parathyroid gland. It has
99% accuracy in differentiating parathyroid from
non-parathyroid tissue. It is not reliable in distinguishing an adenoma from hyperplasia.
Limitation of Frozen Section is its inability to
determine whether the remaining parathyroid
glands function normally, therefore not being
able to conrm cure.
Methylene blue injected intravenously approximately an hour before surgery has been widely
used to aid intraoperative localization of parathyroid glands. The evidence from retrospective
t.me/Dr_Mouayyad_AlbtousH
448
T. R. Kurzawinski
studies suggests that though operative times are
reduced, use of methylene blue did not demonstrate signicant improvement in cure rate or
recurrence. Methylene blue can cause anaphylaxis and the serotonin syndrome in patients taking selective serotonin reuptake inhibitors.
Because of its neurotoxicity manifesting as toxic
metabolic encephalopathy, it should be used with
caution.
Fluorescence-guided parathyroidectomy is
used to locate and differentiate the normal and
enlarged parathyroid glands. Patients take oral
aminolevulinic acid (ALA) 4–5 h prior to surgery. The operating eld is illuminated with
violet- blue light (405 nm wavelength), to which
the parathyroid glands selectively demonstrate
red uorescence. Initial case series reported good
ability to identify the parathyroid glands, but
potential side effects include skin sensitivity to
normal light (patients remain in hospital for
24–28h post procedure in dim-lit rooms to avoid
this), transient elevation in liver enzymes, nausea, and vomiting.
Radioguided parathyroidectomy (RGP)
involves the injection of MIBI preoperatively and
the use of a portable γ-probe to localize the
abnormal parathyroid in vivo and determine
ex vivo radioactivity count after the excision.
Parathyroid adenomas radioactivity count is
59%, while thyroid and hyperplastic glands count
is 16% above background activity. Using a cutoff
of 20% with a positive MIBI scan preoperatively,
excision of abnormal parathyroid could be conrmed. In patients where the excised glands do
not meet the count criteria of >20% of the background count, further exploration of the contralateral side is performed through the same
incision. Reported success rates for RGP are high
at 93–97%. RGP can be also successfully performed regardless whether preoperative MIBI
scans are positive or negative. Disadvantage of
this technique is cost, logistics, and exposure to
radiation.
Intraoperative parathyroid hormone (IOPTH)
monitoring is possible because, in patients with
normal renal function, PTH has a biological halflife of <5min. Therefore, removal of the abnormal, hypersecreting parathyroid gland results in
rapid reduction in the PTH levels. Blood sampling is done before, at 5 and 10min after excision of the abnormal parathyroid and biochemical
cure is conrmed by 50% reduction of PTH compared to the highest pre-excision level (Fig.15.3).
Measurements are done in the operating theatre
next to the patient and take 12min. Monitoring of
IOPTH is the simplest and most effective technique of conrming cure and success of operation. It helps to overcome the inaccuracies of
preoperative localization studies when multigland disease has been missed. Persistently high
PTH level indicates that not all abnormal glands
were removed and further exploration and is necessary [22, 23]. Monitoring of IOPTH is most
helpful in patients with discordant imaging,
patients who had single preoperative localization
study (e.g., only US in pregnant women), and in
reoperations for recurrent HPT. Monitoring of
IOPTH changed operative management in only
2% of cases with concordant but in 74% of cases
with discordant imaging. The IOPTH assays in
the removed specimen can be also used to differentiate between parathyroid and non-parathyroid
tissue; however, frozen section may be superior
for this purpose. Its disadvantage is high cost.
15.7.3 Special Situations
PHPT in children differs from PHPT in adults
in that it is 100 times less frequent, equally common in boys and girls, more frequently familial
and almost always symptomatic at presentation.
Neonates are exclusively affected by CaSR
mutations causing Neonatal Severe HPT.Older
children have higher proportion of familial to
sporadic disease and routine genetic testing is
recommended. Despite these differences, biochemical and genetic testing as well as preoperative localization studies have the same
accuracy and value in both children and adults.
Sporadic PHPT in children, similarly to adults,
is caused in great majority of cases by single
parathyroid adenoma and can be cured by
MIP. Children with familial PHPT should
undergo BNE and removal of multiple abnormal
parathyroid glands [24].
t.me/Dr_Mouayyad_AlbtousH
15 Surgery ofParathyroid Glands
Fig. 15.3 Comparison
of IOPTH concentration
changes during surgery
measured by main
laboratory platform and
equipment based in
theatre
449
PHPT in pregnancy is a risk to mother and
baby and is frequently diagnosed late. It presents
as dehydration, hyperemesis, and preeclampsia
and is associated with 3.5 fold increase in spontaneous abortion and stillbirth. Fetal effects are
intrauterine growth retardation, low birth weight,
hypocalcemia, and tetany in neonate. Medications
to lower calcium could be used, but parathyroidectomy in the second trimester is safe and best
treatment [25].
Renal hyperthyroidism could be treated
with calcimimetics, but parathyroidectomy is
indicated in XX% of patients poorly con-
t.me/Dr_Mouayyad_AlbtousH
trolled, not responding or having severe side
effects to Cinalacet. Total parathyroidectomy
cures renal HPT, but long-term hypo-parathyroidism can cause adynamic bone disease detrimental to skeletal health. 3½ gland
parathyroidectomy and total parathyroidectomy with auto- transplantation have 90–100%
cure rate at 24months but in long- term recurrence rate ranges from 0 to 80%. Number of
glands to be removed depends on patient age,
stage of disease, and eligibility for renal transplantation and should be always discussed with
nephrology team.
450
T. R. Kurzawinski
PHPT in elderly affects 2% of elderly population and about ¼ of parathyroidectomies for
PHPT are performed in patients older than 70yrs.
Parathyroidectomy in elderly is safe and should
be considered as it offers signicant improvement in symptoms and cardiovascular and skeletal health [26].
Intrathoracic parathyroids can be found in
10% of patients with PHPT. Glands located
above aortic arch can be almost always removed
through cervical approach. Adenomas situated
deeper might require open approach (thoracotomy or partial/full sternotomy) or their minimally invasive alternatives (video-assisted
thoracoscopy or mediastinoscopy). Angiographic
or chemical ablation can also be used [27].
Parathyroid cancer is found in 1% of
patients with PHPT and could present as hard
palpable mass. It should be also suspected in
patients with normal examination but very high
levels of calcium and PTH.Inltrating tumours
should be resected with adjacent thyroid and
involved soft tissue. If the diagnosis is made
postoperatively on histology, second operation
and hemi- thyroidectomy should be considered.
Local recurrence develops in about 10% of
patients and 5 and 10years survival is 86% and
49%, respectively. Distant metastases and associated hypercalcemia should be treated with
combination of ablation procedures and systemic therapy to control calcium (Cinacalcet)
and chemotherapy [28].
Redo parathyroidectomy is necessary in
5–10% of patients with recurrent or persistent
PHPT. Commonest causes of failure are wrong
diagnosis, suboptimal imaging, ectopic glands,
familial disease, and inexperienced surgeon. If
reoperation is necessary, it is essential that diagnosis of PHPT is conrmed and imaging, operating notes and histology of previous surgery
reviewed. Additional imaging and relevant
genetic tests should be carefully planned.
Majority of redo operations are neck explorations
sometimes combined with sternotomy but MIP
or thoracoscopy should be considered.
Reoperations have increased risks of postoperative complications, but success rate is high at
90–95% [29, 30].
References
1. Steward DL, Hairston JA.Development and surgical
anatomy of the thyroid compartment. In: Terris DJ,
Gourin CG, editors. Thyroid and parathyroid diseases. NewYork, NY: Thieme; 2009. p.11–7.
2. Gardner DG, Shoback D.Greenspan’s basic & clinical endocrinology. 9th ed. McGraw Hill; 2011. p.232.
ISBN 978-0071622431
3. Yu N, Leese GP, Smith D, Donnan PT.The natural
history of treated and untreated primary hyperparathyroidism: the parathyroid epidemiology
and audit research study. QJM. 2011;104:513–21.
https://doi.org/10.1093/qjmed/hcq261. Epub 2011
Jan 25
4. Rubin MR, Bilezikian JP, McMahon DJ, et al. The
natural history of primary hyperparathyroidism with
or without parathyroid surgery after 15 years. J Clin
Endocrinol Metab. 2008;93:3462–70. https://doi.
org/10.1210/jc.2007- 1215. Epub 2008 Jun 10
5. Perrier ND. Asymptomatic hyperparathyroidism: a
medical misnomer? Surgery. 2005;137:127–31.
6. Teh BT, Kytola S, Farnebo L, etal. Mutation analysis of the MEN1 gene in multiple endocrine neoplasia type 1, familial acromegaly and familial isolated
hyperparathyroidism. J Clin Endocrinol Metab.
1998;83(8):2621–6.
7. Carpten JD, Robbins CM, Villablanca A, et al.
HRPT2, encoding parabromin, is mutated in
hyperparathyroidism- jaw tumor syndrome. Nat
Genet. 2002;32(4):676–80.
8. Shattuck TM, Valimaki S, Obara T, et al. Somatic
and germ-line mutations of the HRPT2 gene in
sporadic parathyroid carcinoma. N Engl J Med.
2003;349(18):1722–9.
9. Howell VM, Haven CJ, Kahnoski V, et al. HRPT2
mutations are associated with malignancy in
sporadic parathyroid tumours. J Med Genet.
2003;40(9):657–63.
10. Elisei R, Romei C, Cosci B, et al. RET genetic
screening in patients with medullary thyroid cancer and their relatives: experience with 807 individuals at one center. J Clin Endocrinol Metab.
2007;92(12):4725–9.
11. Lubitz CC, Stephen AE, Hodin RA, Pandharipande
P. Pre operative localization strategies for primary
hyperparathyroidism: an economic analysis. Ann
Surg Oncol. 2012;19:4202–9.
12. Vaz A, Grifths M.Parathyroid imaging and localization using SPECT/CT: initial results. J Nucl
Med Technol. 2011;39(3):195–200. https://doi.
org/10.2967/jnmt.110.085522. Epub 2011 Jul 27
13. Nguyen BD.Parathyroid imaging with Tc-99m sestamibi planar and SPECT scintigraphy. Radiographics.
1999;19(3):601–14.
14. Abikhzer G, Levental M, Rush C. High resolution
MRI in the detection of an intrathymic parathyroid
adenoma. Br J Radiol. 2006;79(945):78–80. https://
doi.org/10.1259/bjr/26663397.
t.me/Dr_Mouayyad_AlbtousH
15 Surgery ofParathyroid Glands
451
15. Kountakis SE, Maillard AJ. Parathyroid adenomas: is bilateral neck exploration necessary? Am J
Otolaryngol. 1999;20(6):396–9.
16. El-Sharaky M, Khalil M, Sharaky O, Sakr M, Fadaly
G, El-Hammadi H, Moussa M.Assessment of parathyroid autotransplantation for preservation of parathyroid function after total thyroidectomy. Head
Neck. 2003;25(10):799–807.
17. Sosa JA, Udelsman R. Minimally invasive parathyroidectomy. Surg Oncol. 2003;12(2):125–34.
18. Brunaud L, Zarnegar R, Wada N, Ituarte P, Clark OH,
Duh QY. Incision length for standard thyroidectomy
and parathyroidectomy: when is it minimally invasive? Arch Surg. 2003;138(10):1140–3.
19. Agarwal G, Barraclough BH, Reeve TS, Delbridge
LW. Minimally invasive parathyroidectomy using
the ‘focused’ lateral approach. II.Surgical technique.
ANZ J Surg. 2002;72(2):147–51.
20. Kell MR, Sweeney KJ, Moran CJ, Flanagan F, Kerin
MJ, Gorey TF.Minimally invasive parathyroidectomy
with operative ultrasound localization of the adenoma.
Surg Endosc. 2004;18(7):1097–8.
21. Rio PD, Vicente D, Maestroni U, Totaro A, Pattacini
GM, Avital I, etal. A comparison of minimally invasive video-assisted parathyroidectomy and traditional parathyroidectomy for parathyroid adenoma. J
Cancer. 2013;4:458–63.
22. Morris LF, Zanacco K, Ituarte PHG, Ro K, Duh QY,
Sturgeon G, Yeh MW. The value of intraoperative
parathyroid hormone monitoring inlocalized primary
hyperparathyroidism: a cost analysis. Ann Surg
Oncol. 2010;17:679–85.
23. Carneiro DM, Solorzano CC, Nader MC, Ramirez
M, Irvin GL 3rd. Comparison of intraoperative iPTH
assay (QPTH) criteria in guiding parathyroidectomy: which criterion is the most accurate? Surgery.
2003;134(6):973–9.
24. Alagaratnam S, Kurzawinski TR.Aetiology, diagnosis and surgical treatment of primary hyperparathyroidism in children: new trends. Horm Res Paediatr.
2015;83(6):365–75. May 1 [Epub ahead of print]
25. Dochez V, Ducarme G. Primary hyperparathyroidism during pregnancy. Arch Gynecol Obstet.
2015;291(2):259–63. https://doi.org/10.1007/s00404-
014- 3526- 8. Epub 2014 Nov 4
26. Jacobs L, Samson MM, Verhaar HJ, Koek
HL. Therapeutic challenges in elderly patients with
symptomatic hypercalcaemia caused by primary
hyperparathyroidism. Neth J Med. 2012;70(1):35–8.
27. Shende MR, Pusca SV, Quinlan DP Jr, Bolanowski
PJ, Donahoo JS.Intrathoracic parathyroid adenoma.
Ann Thorac Surg. 2004;77(2):724. PMID: 4759477
28. Mittendorf EA, McHenry CR.Parathyroid carcinoma.
J Surg Oncol. 2005;89(3):136–42.
29. Shen W, Duren M, Morita E, et al. reoperation for
persistent or recurrent primary hyperparathyroidism.
Arch Surg. 1996;131:861–7.
30. Caron NR, Sturgeon C, Clark OH.Persistent and recurrent hyperparathyroidism. Oncology. 2004;5:335–45.
t.me/Dr_Mouayyad_AlbtousH
Thyroid andParathyroid
Endocrine Emergencies
MahmoudSakr
16
16.1 Overview
Thyrotoxic storm and myxedema coma are
uncommon, though important life-threatening
endocrine emergencies that result from extreme
hyperthyroidism and hypothyroidism, respectively, with multiorgan dysfunction. Rapid diagnosis and prompt adequate treatment are
mandatory to prevent their deleterious consequences and fatal outcome. Therefore, it is
important that surgeons understand the clinical
presentation, pathophysiology, and appropriate
treatment of these conditions as they may be precipitated by trauma and critical illness, and
patients with untreated or inadequately treated
pre-existing hyperthyroidism or hypothyroidism
may require urgent operations [1].
The clinical presentation of patients with thyrotoxic storm includes fever, tachycardia, hypertension, and neurological and gastro-intestinal
(GI) abnormalities. Hypertension may be followed by congestive heart failure (CHF) that is
associated with hypotension and shock. Diagnosis
is primarily clinical, and no specic laboratory
tests are available. Since thyrotoxic storm is
almost invariably fatal if left untreated, rapid
diagnosis and prompt treatment are critical.
Myxedema coma, on the other hand, is the
M. Sakr (*)
Department of Surgery, Faculty of Medicine,
Alexandria University, Alexandria, Egypt
extreme clinical manifestation of severe hypothyroidism. The main clinical features are progressive deterioration of the level of consciousness,
hypothermia, hypoventilation, hyponatremia,
bradycardia, hypotension, and seizures [2].
Patients with both thyrotoxic storm and myxedema coma should be managed in an intensive
care unit (ICU) with continuous electrocardiogram (ECG), arterial blood gas (ABG), and central venous pressure (CVP) monitoring. In
addition, bacterial infection should be sought and
properly treated in both conditions. Delay in
instituting therapy and premature weaning from
the ventilator are common pitfalls in the management of patients with myxedema coma. Moreover,
adverse reactions can occur with the administration of vasopressors, sedatives, or tranquilizers
and with active rewarming for hypothermia in
patients with myxedema coma [1].
Parathyroid (hypercalcemic) crisis is a reversible, curable, but life threatening. If proper treatment is not initiated promptly, rapid progression
ending in death may occur. In hospitalized patients,
the most common cause of hypercalcemia is
malignancy, whereas in ambulatory patients, primary hyper-parathyroidism (PHPT) is the most
common cause. The clinical manifestations
include weakness, nausea and vomiting, drowsiness, stupor, coma, constipation, and tachycardia
[3, 4]. Severe life-threatening symptoms and signs
of hypercalcemia constitute a “crisis,” and rapid
diagnosis and prompt treatment are essential to
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2024
M. Sakr (ed.), Head and Neck and Endocrine Surgery,
https://doi.org/10.1007/978-3-031-64102-2_16
t.me/Dr_Mouayyad_AlbtousH
453
454
M. Sakr
avoid signicant morbidity or death [5].
Hypercalcemic crisis patients should be treated in
the ICU. Emergency treatment of hypercalcemic
crisis is the same regardless of the cause and consists of early uid replenishment and promotion of
calciuresis with normal saline and loop diuretics.
Bisphosphonates and calcitonin may be subsequently added. The introduction of the intact PTH
assay for the routine diagnosis of HPT, the use of
preoperative localization studies, the liberal use of
intraoperative parathyroid hormone (PTH) monitoring, and improvements in the technical expertise of head and neck and endocrine surgeons have
led to an improvement in outcome of patients with
PHPT.Optimized strategies for the intensive care
of critically ill hypercalcemic patients have made
hypercalcemic crisis a rare event [6].
Hypoparathyroidism is most commonly
caused by surgery for parathyroid disease, thyroid disease, or extensive head and neck cancers.
Patients with hypoparathyroidism often display
signs and symptoms of hypocalcemia and exhibit
diminished serum calcium (Ca), elevated serum
phosphorus, and reduced serum PTH.The typical
signs and symptoms associated with hypocalcemia are neuro-muscular irritability, including
peri-oral or acral paresthesias, muscle cramps
that may progress to carpo-pedal spasm, laryngospasm, broncho-spasm, or even tetany. Severe
hypocalcemia resulting from any cause can be
life threatening; therefore, establishing the appropriate diagnosis and initiating prompt therapy is
critical. Close monitoring is indicated to determine if long-term therapy is necessary [7, 8].
16.2 Thyrotoxic Storm
16.2.1 Denition andSynonyms
Thyrotoxic storm is an acute, life-threatening,
hyper-metabolic state induced by excessive
release of thyroid hormones in patients with thyrotoxicosis [9]. Synonyms include thyroid storm,
thyrotoxic storm, thyroid crisis, and thyrotoxic
crisis.
16.2.2 Epidemiology
16.2.2.1 Frequency
Thyrotoxic storm has become a rare disorder
owing to the early recognition, adequate suppression prior to thyroid surgery, administration of
appropriate anti-thyroid drugs (ATDs), and the
popularity of radioactive iodine (RAI) therapy
for treating patients with thyrotoxicosis. The
incidence of thyrotoxicosis increases with age. In
the United States (US), thyrotoxicosis may affect
as many as 2% of older women. Children constitute <5% of all thyrotoxicosis cases. Graves’ disease is the most common cause of childhood
thyrotoxicosis and, reportedly affects 0.2–0.4%
of the pediatric and adolescent population. In the
US survey, approximately, 16% of inpatients
with thyrotoxicosis in the United States were
diagnosed with storm [10]. Based on nationwide
surveys conducted between 2004 and 2008, the
rate of thyrotoxic storm in Japan in all thyrotoxic
patients is 0.22%, and in hospitalized thyrotoxic
patients, 5.4% [11].
16.2.2.2 Gender
Thyrotoxic storm affects a small percentage of
patients with thyrotoxicosis, which is 3–5 times
more common in females than in males, especially among pubertal children. The incidence is
presumed to be higher in females; however, no
specic data regarding sex-specic incidence are
available [11].
16.2.2.3 Age
Neonatal thyrotoxicosis occurs in only 1–2% of
neonates born to mothers with Graves’ disease.
Infants younger than 1year constitute only 1%
of cases of childhood thyrotoxicosis. More than
two-thirds of all cases of thyrotoxicosis occur in
children aged 10–15years. In general, thyrotoxicosis occurs most commonly during the third
and fourth decades of life. Because childhood
thyrotoxicosis is more likely to occur in adolescents, thyrotoxic storm is more common in this
age group, although it can occur in patients of all
ages [11].
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16.2.3 Etiology
Several factors may precipitate the progression of
thyrotoxicosis to thyroid storm. In the past, thyroid
storm was commonly observed during thyroid sur-
gery, especially in older children and adults, but
improved pre-operative management has markedly decreased the incidence of this complication.
Today, thyroid storm occurs more commonly as a
medical crisis rather than a surgical crisis.
Non-thyroid surgery, major trauma, infection,
and image studies using iodinated contrastmedium in patients with unrecognized thyrotoxicosis may precipitate a thyroid storm. For
unequivocal cases of thyroid storm, pneumonia,
peptic ulcer perforation, and co-existent hyperparathyroidism (HPT) with extreme hypercalcemia (serum calcium >15 mg/dL) were also
considered precipitating factors [1].
Thyroid and non-thyroid precipitating factors
of thyrotoxic storm in patients with thyrotoxicosis are summarized in Table16.1 [12–14].
Other reported causes of thyrotoxicosis associated with thyrotoxic storm include transplacental passage of maternal thyroid-stimulating
immunoglobulins in neonates, and McCune-
Albright syndrome (a disorder that affects the
bones, skin, and several endocrine tissues) with
autonomous thyroid function [18].
In children with thyrotoxicosis, thyrotoxic
storm is most commonly associated with Graves’
disease, but it can occur from any cause. Graves’
disease may also occur in children with Down
syndrome or Turner syndrome, and in association
with other autoimmune conditions including
juvenile rheumatoid arthritis, Addison disease,
Type-I diabetes mellites (DM), myasthenia gravis, chronic lymphocytic (Hashimoto) thyroiditis, systemic lupus erythematosis (SLE), chronic
active hepatitis, and nephrotic syndrome.
16.2.4 Pathogenesis
Although the exact pathogenesis of thyroid storm
is not fully understood, the following theories
have been proposed:
– Patients with thyrotoxic storm have relatively
higher levels of “free” thyroid hormones than
patients with uncomplicated thyrotoxicosis,
although “total” thyroid hormone levels may
not be increased [19].
– Adrenergic receptor activation is another
hypothesis. Sympathetic nerves innervate the
thyroid gland, and catecholamines stimulate
thyroid hormone synthesis. In turn, increased
thyroid hormones increase the density of
β-adrenergic receptors, thereby enhancing the
effect of catecholamines [20]. This theory is
supported by the dramatic response of thyrotoxic storm to β-blockers, and the precipitation of the storm after accidental intake of
adrenergic drugs such as pseudo-ephedrine.
This theory also explains normal or low
plasma levels and urinary excretion rates of
Table 16.1 Thyroid and non-thyroid precipitating factors of thyrotoxic storm
Thyroid causes Non-thyroid causes
– Thyroid surgery under inadequate suppression
– Abrupt withdrawal of or noncompliance with
anti-thyroid drug therapy
– Excessive thyroid hormone intake
– Radioactive iodine (RAI) therapy [15]
– Vigorous palpation of an enlarged thyroid gland
– Direct trauma to the thyroid gland
– Iodinated contrast dyes
– Thyroid- stimulating hormone (TSH)-secreting tumor
NSAIDs nonsteroidal anti-inammatory drugs
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– Infection (sepsis)
– Cerebro-vascular accident
– Pulmonary thrombo-embolism
– Parturition
– Diabetic ketoacidosis (DKA) [16]
– Emotional stress
– Trauma, e.g., hip fracture
– Hypoglycemia and hyperglycemia
– Hypercalcemia
– Drugs (anti- cholinergic and adrenergic drugs),
salicylates, NSAIDs, chemotherapy [17]
– Emotional stress
– Intense physical exercise
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