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Introduction
Surgical Anatomy
Surgical Strategy
Hemithyroidectomy
 Access to gland
 Exposure of the ESLN and the superior pole vessels
 Identifying the RLN and the parathyroids
Total thyroidectomy
Partial thyroidectomy
 Technique
Wound Closure
Postoperative Care and Complications
Summary
Recommendations
References
Introduction
The thyroid operation is considered by many to be at the pinnacle of
endocrine surgery. The surgeon who can perform a good thyroidectomy can,
with little additional training, handle most of the other operations in this
field, because the technique required is much the same. Most endocrine
surgeons agree that an accurately performed thyroidectomy requires both
experience and technical ability. This has lead various national endocrine
surgical associations to strive for the creation of centers of excellence for the
future training of endocrine surgeons(1;2).
Unacceptably high incidences of major complications, like recurrent
laryngeal nerve palsies and permanent hypoparathyroidism are still reported
in the surgical literature. Experience, sound judgment, meticulous technique
and adequate training are the hallmarks required to eliminate these (3).
Notwithstanding the limited facilities, the shortage of trained staff and
inefficient health planning programs in developing countries, it is possible to
make up for the shortcomings with a little more enthusiasm and dedication
to achieve better results. It would be prudent to design appropriate training
programs and introduce uniform guidelines and standards for performing
these operations for the whole East and Central African region.
Due to our unique disadvantaged position in the medical world, there has
been a tendency to copy-cat everything without consideration to our unique
cultures, customs and priorities. A typical example is: the indications of
surgery for a benign asymptomatic goiter in an old African lady and her
counterpart in the West should not be the same in my opinion. The concept
of cosmetics is rather different in both women. Lack of a health insurance
system worth talking about and rampant poverty should also encourage a bit
of conservatism when it comes to indications for thyroidectomy.
Controversy on the best surgical procedure for various types of goiters still
rages in the West, although the tendency is toward radical techniques, even
for benign lesions. There are documented advantages of total thyroidectomy
for some cases of benign goiter as pointed out by Bron and others(4;5).
Delbridge is a proponent for total thyroidectomy in almost all benign goiters
in which surgery is indicated(6).The more conservative surgeons are mainly
concerned about increased debilitating complications associated with the
radical techniques. When these operations are attempted by inexperienced
novices in small poorly equipped hospitals, the complication rates and
gravity are not any different from what Kocher, Billroth and Mickulicz and
many others experienced in the 19th century(4). And yet these recently
graduated rural surgeons, who might have assisted in several thyroid
operations during training, feel motivated to attempt these techniques; just
because the gurus of endocrine surgery recommend it in conferences and on
the internet. The results are usually catastrophic.
Recent innovations in thyroid surgery include minimal access and
laparoscopic techniques as popularized by Miccoli and others(7;8).
Obviously these would not be applicable to the huge endemic goiters seen in
developing countries, although they have their applications for small benign
nodules and parathyroid adenomas. There is also quite a debate going on as
to the usefulness of these techniques in comparison to open thyroidectomies,
as they actually leave significant scarring, especially the so called videoassisted minimal access. Mammary and axillary approaches have been
introduced to eliminate cervical scars(8;9). Outpatient thyroidectomy and
short stay procedures are now well established(10), but should be used in
selected patients because of the risk of bleeding(11).
Surgical Anatomy
The surgeon must be familiar with the normal anatomy of the neck and the
anatomical course and position of the laryngeal nerve and the location and
blood supply of the parathyroid glands in order to be able to perform
successful thyroid surgery. The Tubercle of Zuckerkandl is a thickening of
thyroid tissue that is located at the most posterolateral edge of the thyroid
gland (Fig.1).
Superior
parathyroid
gland
Organ of
Zuckerkandl
Fig.1
Its importance lies in its close proximity with the parathyroid glands and the
RLN. This stresses the need for good exposure as a general principle during
thyroid operations.
It is a fundamental surgical principle that to avoid damaging any vital
structure at operation that structure must be clearly identified by the surgeon.
The recurrent laryngeal nerve (RLN) at thyroidectomy is no exception to this
rule(12). Clark reported zero rates of RLN injury in a large series of total
thyroidectomies for thyroid cancer using this strategy(13). The reported
incidence of the RLN palsy varies from 0% to 14%. Several factors
influence the likelihood of injury to the nerve, including the underlying
disease, the extent of resection, and the experience of the surgeon. Bleeding
should and can be kept to a minimum and the use of diathermy should be
avoided in the vicinity of the laryngeal nerves. Iatrogenic injury to one nerve
may be asymptomatic, but often results in patient morbidity from hoarseness
and reduced vocal range. Bilateral nerve injury results in complete voice
loss, with or without major respiratory distress(14)(Fig.2). Rosato and other
authors have reported on various factors that could lead to voice changes
post thyroidectomy besides iatrogenic injury(14-16). This underlines the
importance of both pre and post operative voice assessment, although Yeung
has found indirect laryngoscopy of limited value in the preoperative
assessment of symptomatic patients(17). A full assessment may not always
be possible in a district hospital, but basic IL of the vocal cords is within the
skills of a rural general surgeon. It is more complex to assess injuries of the
superior laryngeal nerve and its branches. A non-recurrent laryngeal nerve is
rare but failure to identify it could cause inadvertent injury and dire
consequences.
Recurrent
Laryngeal
nerve
Inferior
thyroid
artery
Fig.2
The external laryngeal branch of the superior laryngeal nerve (ESLN)
provides motor innervation to the cricothyroid muscle. This muscle is
responsible for tensing the vocal cords and its injury leads to weakness of
voice. It runs in close proximity to the superior thyroid artery and is
therefore vulnerable when the vessels of the superior pole are ligated, even
when this pole is not enlarged. The internal branch is rarely subject to injury
during thyroidectomy, except when an enlarged upper pole extends above
the upper border of the thyroid cartilage. This leads to choking and
aspiration due to loss of sensation to the upper half of the larynx (Fig.3)
Superior
Laryngeal
nerve
Internal
branch
External
branch
Fig.3
Most humans have four parathyroid glands. Supernumery glands have been
reported to be between 2.5% and 22% in different studies. The exact number
of individuals with fewer than four glands is difficult to determine as the
missing gland could represent an unobserved rather an absent gland(18). The
parathyroid glands lie on the posterior surface of the thyroid gland (Fig.1).
The superior gland is located commonly on the posterolateral aspect in the
tracheo-esophageal groove 1-2 cm above the intersection of the RLN and the
inferior thyroid artery, within an area of the same radius. Unusual locations
include intrathyroid, posterior aspect of neck above the upper thyroid pole,
and the retropharyngeal space.
The inferior parathyroids are very inconsistent in position, their commonest
location being the posterolateral aspect of the lower pole of the thyroid
gland, below the inferior thyroid artery. They are sometimes located in the
superior mediastinum within the thymus.
Surgical strategy
Total thyroid lobectomy (as distinct from nodulectomy or partial lobectomy)
is the total extracapsular removal of one lobe and the isthmus, preserving an
intact RLN, SLN and viable parathyroid glands. Total thyroidectomy (as
distinct from subtotal or near total thyroidectomy) is the performance of a
total thyroid lobectomy on both sides at the same sitting(19).
When the technique of total thyroid lobectomy is mastered, it is then
possible to perform other procedures on the thyroid gland with ease. That is
why it is the first step in the training of thyroid surgery in most centers. This
technique is recommended for all unilateral nodules for the following
reasons:
a. This avoids re-operating on the same side if further surgery is
required, with the associated increased risk of complications and
technical difficulty. Neither FNAC nor frozen section will always give
the correct histopathological diagnosis(20;21).
b. Technically it could be easier than a partial resection when mastered,
as there is less bleeding with better delineation of the anatomical
structures.
We shall describe the technique of hemithyroidectomy in detail followed by
descriptions of the other steps and modifications required for a ‘partial
thyroidectomy’ and total thyroidectomy.
Hemithyroidectomy
A general anesthetic is generally required for thyroidectomy, although it is
possible to perform the procedure under a local anesthetic. Spanknebel et al.
reported 1025 consecutive thyroidectomies done under local anesthesia over
a 16 year period(22). It is an extremely uncomfortable and frightening
experience for the patient. Personally, I believe local anesthesia should be
relegated to high risk patients in whom a general anesthetic is
‘contraindicated’ or in remote areas where an anesthetist or clinical officer is
not available. Overextension of the neck should be avoided especially in the
elderly. A roll or firm pillow placed transversely under the shoulders with
adequate head support is essential to the proper positioning for
thyroidectomy. Both arms should be placed comfortably by the sides and
held with towels tucked under the patient, with additional padding at the
elbows to avoid pressure on nerves. A 15-20 degree upward tilt of the head
of the table improves exposure and reduces venous congestion in the neck
(23;24) (Fig.4).
Access to the gland
The site of the incision is marked on the ward with the patient’s neck in the
neutral position. A crease line is the best but it should not be less than 2cm
or 1 finger breath from the jugular notch, especially in black patients who
are prone to keloid formation below this line(25). The extent from the
midline will depend on the size of the goiter and the length of the neck, but
rarely more than 5cm each side for the average goiter (Fig.5). In case of
large goiters we do not hesitate to extend the incision on either side(26).
Ikeda et al. use a mini-incision of 3 cm.(27). This is probably possible in
small goiters and not the type we see in our part of the world. We frequently
infiltrate about 40-60 milliliters of ‘Jungle Juice’ beneath the platysma, as it
facilitates the formation of the skin flaps by reducing bleeding. This an old
habit from the pre-diathermy days, which we still find useful. It consists of a
mixture of 180mls normal saline, 20mls of xylocaine 2%, 1 ampoule of
adrenaline 1:1000 and 1 ampoule of hylase.
Fig 5
Fig.6 illustrates the technique of raising the skin flaps. A scalpel or scissors
are both effective and the choice depends on the preference of the surgeon.
Personally I find the Mayo’s scissors effective as it can be used for both
sharp and blunt dissection. The flaps are raised to the thyroid notch
superiorly and to the suprasternal notch inferiorly(24). It is important to stay
anterior to the anterior jugular veins, under the platysma, to achieve a
bloodless dissection. These skin flaps are held apart by one or two Joll’s
self-retaining retractors or wishbone retractors depending on the surgeon’s
preference. In our region, it usually comes down to what is available and the
surgeon should be able to exercise flexibility and use the available
instrument, especially in a rural setting.
Fig.6
The strap muscles are separated by opening the linea alba from just below
the thyroid cartilage up to the jugular notch. This is a relatively bloodless
dissection as it is rare to find significant circulation across the midline and
the vessels could easily be controlled with diathermy when they occur
(Fig.7).
Fig.7
The sternohyoid and sternothyroid muscles are sometimes divided for
greater exposure of a large or vascular lobe (Fig.8). This is more frequently
encountered in developing countries as the goiters tend to be large when the
patients present for surgery, and are often associated with complications like
airway obstruction. All the 4 strap muscles are supplied by the ansa
cervicales nerve which enters the muscles from the lateral border of the
sternothyroid inferiorly. It is recommended to do the transection in the upper
thirds of these muscles to avoid nerve injury(23).
Fig.8
After the above steps, we normally start the freeing of the lobe using the
lateral approach(28). This entails starting at the RLN and the inferior thyroid
artery. Another approach also used by some experienced thyroid surgeons is
the cranial or superior approach (19;24;28). This later approach is preferable
when the goiter is large as it can be difficult to identify the RLN and the
inferior thyroid artery without first mobilizing and dividing the superior pole
vessels(29). We also use the superior technique when the goiter has a
significant retrosternal extension or is intrathoracic. This allows the
complete devascularization of the lobe from above (including if necessary
transection of the isthmus) before delivering the gland gently into the wound
from the superior mediastinum. I have performed a sternotomy only once in
the last 18 years for a retrosternal goiter.
The thyroid lobe is dislocated and delivered medially into the wound by
inserting the index finger between the lobe and strap muscles. Except in the
case of secondary thyroidectomy, it is uncommon to require sharp dissection
at this stage of the operation (Fig. 9)
Fig.9
In patients with toxic goiter or when there is venous obstruction at the
thoracic inlet, large dilated veins are often encountered on the surface of the
lobe. It is absolutely essential to avoid traumatizing these vessels by rough
handling. Our ‘modus operandi’ at this stage has always been working in the
correct plane with gentle index finger dissection and lateral retraction of the
strap muscles. Every thyroid surgeon knows the near impossibility of
controlling bleeding from these vessels. ‘Harmless’ it might be, but quite a
nuisance to the neat surgeon who relies on a bloodless field. Worse still, the
blood trickles down into the all important operative field between the carotid
sheath and the trachea, rendering the exposure of the RLN and the
parathyroid glands hazardous.
Care should also be taken to ligate the middle thyroid vein(s) when
encountered during this maneuver (Fig.10).
Fig.10
The assistant then applies firm lateral retraction on the strap muscles. This
action opens up the ‘de facto’ working space between the carotid sheath and
the trachea (Fig.11). The use of graspers should be avoided even in non
vascular glands, if malignancy is suspected, to avoid breaching the capsule
of the lobe.
Fig.11
Exposure of the external branch of the superior laryngeal nerve and the
superior thyroid vessels
With the aid of firm lateral traction by the assistant with the surgeon
applying a gentle medial and upward pull on the dislocated lobe, the
operative field between the carotid sheath and the thyroid gland can be
opened up with careful blunt and sharp dissection. As soon as the inferior
thyroid artery is identified, it is followed medially to its intersection with the
recurrent laryngeal nerve, if already visualized in the tracheo-esophageal
groove. Looping the trunk of the artery at this stage facilitates the dissection
and improves the exposure of the recurrent laryngeal nerve. This suture
should be removed when the dissection has been completed.
The next step is to fully mobilize the lobe by ligation of the superior pole
vessels. Here care should be taken to preserve the external branch of the
superior laryngeal nerve. The upper pole is exposed by gentle downward
traction on the lobe and blunt dissection laterally to break down fibrous
adhesions. The ESLN is usually identified on the surface of the inferior
pharyngeal constrictor before it enters the cricothyroid muscle (Fig.12).
Fig.12
This is achieved by opening the space medial to the superior thyroid artery
with an artery forceps or a pledget. Due to anatomical variations and
frequent intramuscular locations (10%), it is only visualized on the
constrictor in about 70% of cases. Mass ligation of the upper pole vessels
should be avoided as the nerve passes between the branches of the vessels in
about 20% of cases(24). These vessels are divided individually close to the
gland with absorbable sutures to avoid injury to the ESLN. I do not hesitate
to do mass ligation of the pole if the nerve has already been visualized.
Nerve stimulation is frequently used in many centers and aids in the
identification of these nerves with reduced frequency of iatrogenic damage
(30;31). Friedman et al. believe a proper understanding of the 3 common
positions of the ESLN mentioned above is the best way to improve their
identification at surgery(32). These injuries are usually over looked as they
are difficult to diagnose at laryngoscopy. The initial symptoms are often
minimal and regarded as ‘normal post-thyroidectomy voice changes’. The
weakening of the voice is especially troublesome to professional speakers
and singers, not to mention mothers of small children.
Identifying the recurrent laryngeal nerve and the parathyroids
It is now generally accepted that the branches of the inferior thyroid artery
should be controlled high up on the capsule of the gland to avoid
devascularising the parathyroid glands (Fig.13). This is the technique of
capsular dissection which has been popularized by Delbridge and co-authors
and adapted in most endocrine centers(6). The standard technique used in
the 1970s was to identify the recurrent laryngeal nerve early in the procedure
as it lay in the tracheo-esophageal groove. It was then dissected up to the
cricopharyngeus removing all the tissues medially while attempting to
preserve the blood supply of the parathyroids. Vascular compromise is very
likely when the medial blood supply is interrupted, even when their pedicles
are identified and protected. Secondly, the excessive dissection of the RLN
resulted in neuropraxia of the nerve due to interference with its neuronal
blood supply. This technique is no longer recommended.
Fig 13
Dolapci et al. reported that they did not encounter any significant increase in
the incidence of hypocalcaemia when they performed truncal ligation of the
ITA during bilateral subtotal thyroidectomies in a prospective study(33).
However, considering the morbidity of permanent hypoparathyroidism (34),
it is strongly recommended not to jeopardize the blood supply of the
parathyroid glands, even during lobectomies. It would be a near disaster for
poor African patients with no medical insurance and living on less than 2
dollars a day to have to purchase calcium and vitamin D tablets for the rest
of their lives. We now only do truncal ligation of the inferior thyroid artery
in case of technical difficulties and limit it to one side only, as much as
possible.
The actual location and identification of the parathyroids and the RLN has
already been referred to in the discussion on surgical anatomy in this review.
With the technique of capsular dissection, it is possible to push the
parathyroids gently downwards while dissecting the lobe off the surface of
the trachea. This minimal handling of the parathyroids reduces the chances
of interfering with their blood supply. It has also become common to auto
transplant the parathyroids (PT) during thyroidectomy to reduce the
incidence of permanent hypoparathyroidim(35). Clear indications for PT are
inadvertent devascularization or devascularization during surgery. The
sternomastoid muscle and forearm muscles are the common sites for PT.
The lower parathyroids are frequently located ectopically in the thymus, so it
is not always possible to identify all parathyroids in all patients.
The RLN is ‘encountered’ usually near the ligament of Berry, rather than
being dissected along its entire length(6). The critical point is superiorly,
where the nerve enters the ligament of Berry and could be easily injured
while handling the organ of Zuckerkandl. From here medial dissection
between the gland and the trachea is continued. It is mandatory to avoid any
form of electro-cautery in the vicinity of the RLN as it could be damaged by
conducted heat. Troublesome bleeders could be controlled with fine
absorbable transfixion sutures (Fig. 14). This dissection is continued
medially until the isthmus is completely freed and the transection made close
to the opposite lobe.
Fig 14
The stump is closed continuously with an absorbable suture in a hemostatic
manner at the same time avoiding bunching up the tissues (Fig.15). During
this dissection, the pyramidal lobe has to be completely excised. It is usually
attached to the left lobe and could be traced as high as the hyoid cartilage. Its
dissection could put the external branch of the superior laryngeal nerve in
danger if done carelessly(19).
Fig.15
Nerve stimulation during surgery has been shown to help in the
identification and protection of nerves, and consequently reducing the
incidence of iatrogenic injury (36). Randolph and group recommend
laryngeal palpation in combination with nerve to stimulation to further lower
the incidence of RLN injuries(37), while Hillermann has come up with a
rather novel but complicated technique with similar intentions. This entails
securing the airway with a micro laryngeal tube and inserting a laryngeal
mask airway through which a fibreoptic scope is introduced to monitor the
larynx during nerve stimulation at thyroidectomy(38). Friedman has
described the need for a thorough understanding of the three anatomical
positions of the ESLN to avoid injury during surgery(32).
Loops are used by some thyroid surgeons to help identify the nerves.
However it is generally accepted that these nerves are large enough for
adequate naked eye visualization. Our unique situation in the third world
does not permit these luxuries to fit into our limited budgets and we have to
make do with plain surgical skill and prayers. The only consolation is that
these gadgets are not a substitute for experience, meticulous technique and
expertise(3).
Total thyroidectomy
This is in reality two hemithyroidectomies. Its indications for benign disease
are still controversial(4), and are not covered in detail in this review.
Complication rates in experienced hands are comparable to less extensive
operations on the gland(6;39). This has been used by its proponents to
recommend its universal adoption. It should be approached with caution in
developing countries for reasons mentioned above.
Every thyroid surgeon should be able to perform a safe, complete
lobectomy. A safe and complete bilateral hemithyroidectomy or total
thyroidectomy, should also be within his or her ability(40).
Partial Thyroidectomy
This procedure is the commonest thyroid procedure done in regions of
endemic goiter. There has been a tendency in the last two decades or so to
perform total thyroidectomies for endemic goitre, mainly in regions around
the Mediterranean(5) and Australia. As mentioned in the first thyroid review
(thyroid 1), we do not differentiate between subtotal and partial
thyroidectomy for benign non- toxic bilateral multinodular goiters. The aim
is to strive to remove all macroscopically affected thyroid tissue and leave
the grossly normal tissue. With this approach, it becomes purely academic to
talk of partial, subtotal and near-total thyroidectomy as the residual tissue
will be determined by the findings. We try to be as conservative as possible
for the reasons mentioned earlier in this review.
Our main indications for surgery in these patients are for pressure
symptoms. Sudden onset of difficulty in breathing is seen when a bleed
occurs into a cyst causing enlargement of the goiter and tracheal
compression. Pressure symptoms are commonly gradual, with the patient
developing breathing difficulties in certain positions of the head. Hoarseness
and severe stridor are not common presentations in simple multinodular
goiters in endemic regions even in massive goiters; and usually indicate
malignant change, notably anaplastic carcinoma. The retrosternal goiter is an
exception as pressure symptoms occur quite early and frequently. Dysphagia
is mainly seen in this group of patients. It is not unusual to encounter
patients on treatment for asthma because of undiagnosed retrosternal goiter.
The stridor is unfortunately mistaken for a wheeze by a busy GP. Another
indication for partial thyroidectomy is cosmetic in city dwellers and young
patients. It is rare for the older patients in rural areas to seek surgical
intervention for cosmetic reasons. Almost everybody in endemic regions,
especially in the country side, has a close relative or a friend who has had a
goiter for as long as they could remember.
Technique
The approach for thyroid resection or partial thyroidectomy is similar to
hemithyroidectomy or lobectomy as described above(28). After securing the
middle thyroid vein(s), upper pole of the gland and the inferior thyroid veins
and delivering the lobe medially; the main difference from the lateral
approach is that we identify the tertiary branches of the inferior thyroid
artery on the capsule of the gland and apply a row of mosquito forceps. The
isthmus is then transected to expose the trachea. This could be a difficult
task in large goiters. Early excision of the pyramidal lobe superiorly and
exposing the trachea inferiorly usually allows the insertion of a long curved
artery forceps between the isthmus and the trachea allowing the introduction
of further forceps and transection-ligation of the isthmus. The later is
dissected off the trachea towards the mobilized lobe. A further row of
mosquito forceps is inserted medially onto the capsule, targeting the visible
blood vessels.
The resection is started by incising the capsule just above the forceps. The
aim is to remove all grossly affected thyroid tissue within the capsule of the
gland, working strictly within the capsule whenever possible. Bleeders are
controlled by applying further mosquito forceps and later transfixed with
fine absorbable sutures. Finally the edges of the capsule are stitched in a
continuous fashion with a 3-0 absorbable suture, enclosing the residual
‘normal’ thyroid tissue. This technique controls the vessels on the capsule
and precludes the need to tie them individually. The same steps are then
repeated on the opposite side. When operating on patients with
thyrotoxicosis, we use the same technique but endeavor to leave about 4gm
of thyroid tissue on each side (Subtotal). The residual tissue for Plummer’s
disease (Toxic nodular goiter) is usually 5-10 gm on each side. Alimoglu et
al. compared the complication rates in 3 groups of patients with toxic
nodular goiters who had total, near-total and partial thyroidectomies done in
one unit as a prospective study. They found no significant difference in the
complications rate(41). The type of surgery for this condition remains one of
the many controversies in thyroid surgery.
The same principles of surgical exposure apply for partial resection as for
doing a hemithyroidectomy. Particular care is required to protect the external
branch of the SLN, the RLN and the parathyroids.
Wound Closure
Meticulous control of bleeders should be standard practice as the use of
drains is not a replacement for hemostasis. Hurtado-Lopez et al. found that
patients in whom drains were used stayed longer in hospital(42). Drains are
not useful if severe postoperative bleeding occurs, but could reduce a small
hematoma. Although used widely, active suction could damage the RLN and
may not actually increase the evacuation capacity(40). Improvised suction
drains using a 20 cc syringe and intravenous giving set tubing (perforated
using a scissors) is very effective active suction. It requires closer
monitoring because of the small capacity and frequent emptying may be
necessary, if proper hemostasis had not been achieved.
If the strap muscles had been transected to improve access to the lobe, they
should be re-approximated with interrupted absorbable mattress sutures 2-0
chromic or PG (Fig. 16). The midline incision and the platysma closure
could be achieved by interrupted or continuous absorbable sutures as per the
surgeon’s preference.
Fig.16
Skin closure can be achieved with subcutaneous stitch, clips or steristrips.
We use a 3/0 or 2/0 nylon subcuticular stitch with anchoring knots at both
ends, which is removed after about 7 days in the clinic. Care should be taken
to allow free sliding at the time of surgery to avoid difficulties of removal
and possible breakage. This is more likely to happen with a 3/0 stitch. It is
cheap, cosmetic and provokes insignificant skin reactions. Staples are ideal
as they could be removed by the 3rd post-op day but tend to be more
expensive. We use absorbable subcuticular stitches selectively because of
the genetic predisposition of the majority of our population to keloid
formation. It is usual to get impatient and recommend revision of scar or
injection of steroids into most hypertrophic scars seen among dark skinned
people. This should be avoided as they mature eventually in 2-3 years with
gradual thinning and flattening of the scar(43).
Peri-operative Care and Complications
Small hematomas or serous collections under the skin flaps are not unusual
during the first week. These resolve spontaneously. Large bleeds requiring
reopening and evacuation of haematoma to relieve pressure symptoms could
be avoided with meticulous technique. Large subcutaneous hematomas
which are unsightly could be aspirated when they liquefy in about 1-2
weeks’ time. Care should be taken to avoid introducing infection during the
needle insertion. Stridor arising from laryngeal edema due to blockage of
venous return by a deep hematoma is best managed by opening the wound
urgently. This may need to be performed at the bed side. If bilateral
recurrent laryngeal nerve injury occurs and both vocal cords are fixed in the
adducted position, severe airway obstruction, requiring a tracheostomy,
results. Occasionally leaving the endotracheal tube in for 48 hours improves
the breathing but unfortunately not the aphonia. A tracheostomy is usually a
last resort. Large doses of hydrocortisone are usually given at this stage in an
effort to reduce the effects of a neuropraxia and the oedema of the injured
nerve. Permanent RLN palsy after partial thyroidectomy is reported in the
literature to be 0-1.3%(44).
We discharge our patients who have no major complications from the
hospital within 3 days, irrespective of the type of thyroidectomy. We do not
perform pre-discharge serum calcium in our patients if they are clinically
asymptomatic postoperatively or if they underwent a lobectomy.
Any muscle pains, paresthesia, twitching or cramps before discharge
indicate hypoparathyroidism and the patients are usually managed
accordingly. 10 mls intravenous calcium gluconate 8 hourly is commenced
at the same time with oral calcium and Alpha D3. It is usually possible to
discharge the patient on oral medications only after 2-3 days, when the
calcium levels have normalized.
The infamous thyroid storm after surgery for toxic goiters is rare among our
patients. We render them all euthyroid pre-operatively, including the use of
small doses of dexamethasone for about five days pre-operatively in brittle
patients. This never fails to render patients euthyroid in combination with
neomercazole (Carbimazole). The maximum dose of Carbimazole is 60 mg
per day in divided doses, preferably. This is reduced gradually as the toxicity
is controlled as evidenced by both clinical findings and biochemical
analysis. If the common complications of skin rash and hematological
disturbancies occur, propylthiouracil is an alternative, albeit more expensive,
treatment modality. B-blockage is useful in the early stages of controlling
the toxic symptoms. Propranolol is our drug of choice in initial doses of 40
mg tid. This rapidly reduces the pulse rate to below 100 per minute. We
rarely use it after the second week of control. Carbimazole is continued until
the evening before surgery. It is also possible to stop it a week before
surgery and control the cardiovascular symptoms with B-blockage. This has
not been our practice although it is reported to lead to lesser bleeding at the
time of surgery. Achieving the best possible control of toxicity is more
important than worrying about some minor harmless and controllable oozing
at surgery.
The need for investigations and the type of tests required during the
postoperative visits are usually determined by the clinical condition of the
patient. The type and extent of the surgery, would determine the need and
urgency of certain investigations. Other factors which should come into
consideration during the postoperative follow-up in developing countries
include availability of the investigative facilities, affordability, and social
status of the patient. It is rarely possible or feasible to perform an exhaustive
check-list of postoperative investigations as we see in developed countries,
except in major urban centers. We perform FT4 and TSH levels on all
patients after partial thyroid resections after 3 months. Any compensated or
overt hypothyroidism is treated with thyroxine accordingly. The optimal
dose after total or near total thyroidectomy is largely influenced by body
weight(45). We do not recommend thyroxine postoperatively in patients
who underwent partial resections if these hormones are within normal limits.
Clinical or symptomatic recurrences are not common, after follow-up of 1215 years, in patients who had adequate resections for benign non-toxic
multinodular goiters in our practice. These patients respond well to small
doses of thyroxine and rarely require secondary thyroidectomy for pressure
symptoms. Recurrencies after subtotal thyroidectomy for Graves’ Disease
led to the current wide use of total thyroidectomy to treat this condition(46).
The current trend is to consult with the patient as to whether they would
rather undergo total thyroidectomy with no risk of recurrence or a lesser
procedure which could lead to a recurrence of up to 20%(46). The need to
take thyroxine for life seems to be of little significance in western societies.
Thyroid cancer developing in a pre-existing multinodular goiter is rare in our
region. These are usually anaplastic in elderly patients with long standing
goiters. I have yet to see a cancer developing in a recurrent nodular goiter
after surgery. Seiler and others have noted an increased incidence of thyroid
cancer in their patients with recurrences after partial thyroidectomy in an
endemic goiter region(47). This is often quoted in the literature as one of the
reasons for recommending total thyroidectomy in patients with multinodular
goiters. We probably need to carry out local controlled studies to justify this
radical procedure on our patients. After all, there are regional disease
patterns and we need our own data to provide evidence based practice.
Summary
Thyroid Surgery requires experience and sound knowledge of the regional
anatomy. The ability to locate the parathyroid glands, recurrent and external
branch of the superior laryngeal nerves as well as familiarity with their
anatomical variations is mandatory.
Complication rates higher than 5% suggest that the surgeon does not have
sufficient training or interest in thyroid surgery. Further training or referral
of patients elsewhere is advisable(40). The currently overall acceptable
complication rates internationally are between 1% and 2%.
It would not be fair to compare the results of a top surgical unit in Sweden to
a district hospital in Kenya or Malawi; but it is possible to narrow the gap by
ensuring good and adequate training, backed by a genuine interest in the
subject.
The collar incision should be well positioned and preferably marked in the
neutral neck position to achieve optimum cosmetic results. Expose the gland
adequately and identify the anatomical structures clearly, while keeping
bleeding to a minimum. Avoid any form of diathermy close to the laryngeal
nerves.
Capsular dissection of the gland and avoidance of ligating the trunk of the
inferior thyroid artery is the internationally accepted approach to minimize
complications without compromising the quality of surgery. The external
branch of the SLN or the ‘neglected’ nerve requires extra effort to identify
and should be preserved or avoided by ligating the superior pole vessels
separately and away from the larynx.
Drains are not a substitute to a good thyroidectomy and their use should be
minimized. It is usually possible to improvise cheap drains using intravenous
fluid giving sets.
Recommendations
 Designing appropriate training programs in the region with the aim of
producing competent surgeons who are able to perform thyroid
surgery with minimal supervision and few complications.
 Establishing uniform protocols for accurate reporting of results.
 Uniform guidelines and standards for performing these operations
using the facilities and expertise available in the region should be
formulated and promoted by the regional and national surgical bodies.
ASEA and COSECSA have already taken general steps in this
direction.
 The indications and extent of surgery for benign thyroid disease in the
third world should not necessarily be the same with the developed
countries, considering our unique environments, cultures and concepts
of disease processes.
 The recommendations given for ‘Goiter 1- Endemic Goiter” in the
May review of SIA also apply for this review.
Acknowledgement
Figures 6-16 were adapted from ‘Operative Strategy in General Surgery’
second Edition. Author: Jameson L. Chassin
Prof. John Adwok
MBBS, MMED, FRCSEd, FCS (ECSA)
Consultant General and Endocrine Surgeon
Department of Surgery
University of Nairobi
Kenya
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