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4 Percutaneous Tracheostomy andOpen Standard Surgical Tracheostomy
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4.3 Indications
In the acute scenario, when there is an impending airway
problem, percutaneous dilational tracheostomy technique is
not indicated and should not be used or form part of the airway management protocol. If a surgical airway is needed, the
gold standard is an open classic surgical tracheostomy, which
can be done under general anaesthesia if the airway is already
safeguarded, or otherwise under local anaesthesia. The acute
airway management protocol should be followed and may
also include the use of emergency cricothyroidotomy, awake
breoptic intubation, and rigid endoscopic intubation techniques, which may be used as necessary. It is important to
familiarise oneself with the acute airway kit in each hospital,
as variations in the type and range of equipment available are
likely in each unit.
In the elective scenario, there are multiple indications that
are common for both percutaneous dilational tracheostomy
and open standard surgical tracheostomy. Upper airway
obstruction can be caused by a multitude of processes, which
may be neoplastic, infective, neurological, or laryngeal, as
well as facial trauma or inammatory causes. If the clinical
situation dictates the need for prolonged intubation and
mechanical ventilation, both techniques can be used according to considerations discussed in the previous section. The
tracheostomy formed will replace the endotracheal tube and
will help to wean off patients from general anaesthesia by
decreasing the dead space and work of breathing, decreasing
the risk of subglottic stenosis, enabling better pulmonary
hygiene, and protecting from recurrent aspirations [10]. It is
also indicated as the last-resort treatment for patients with
obstructive sleep apnoea, but these usually have large necks
with unfavourable anatomy and so are usually offered a standard open surgical tracheostomy. In the intensive care unit
setting, there are a set of absolute and relative contraindications for percutaneous dilational tracheostomy. Unfortunately,
these are not universal and vary between institutions depending on local protocols and clinicians’ experience. For example there are different cut-off ages in the literature for
children to be offered a percutaneous technique. Some clinicians consider high PEEP or FiO2 requirements as contraindications for percutaneous tracheostomy, but these values
again vary according to local practices. If the patient has the
key elements of good neck anatomy and palpable landmarks
and is otherwise deemed to be low-risk, a percutaneous dilation tracheostomy technique offers a quicker solution and
avoids operating room and logistic issues, such as patient
transfer from one hospital area to another.
A classic open surgical tracheostomymay also be performed
as part of another surgical procedure, mostly for prophylactic
airway protection, in the context of treatment of head and neck
cancer. An ‘end’ tracheostomy may be formed in association
with certain procedures, such as a laryngectomy.
4.4 Surgical Technique withTips
4.4.1 Open Standard Surgical Tracheostomy
The adult open surgical tracheostomy is best done in an operating theatre with adequate lighting, suction, and assistance.
A selection of tracheostomy tubes should be available, and
an appropriate size and type of tube should be chosen according to the case. The patient should ideally be intubated under
general anaesthesia and placed in a supine position with the
neck extended using a sandbag or pillow underneath the
shoulders and the head stabilised on a head ring in the midline. Local antiseptic solution is used to sterilise the neck
area, and square sterile draping is applied, taking care to
leave access to the mouth for the anaesthetist. Intravenous
antibiotics are given according to local protocols. Anatomical
landmarks, such as the thyroid notch, cricoid, and suprasternal notch, are marked, and a 3-cm incision is marked halfway between the inferior border of the cricoid and the
suprasternal notch (Fig.4.1). The incision should be placed
correctly, as putting it either too high or too low will make
the procedure more difcult. The incision length may be
increased according to the difculty of the case. The incision
site is inltrated with local anaesthetic containing adrenaline
solution.
An incision is carried out on the marked site and dissection continues though the subcutaneous tissues. This area
can be devoid of platysma bres (especially in thin patients),
and dissection continues until the strap muscles are reached.
Fig. 4.1 After adequate surgical skin preparation and sterile draping,
key neck structures and the incision site are marked. The incision site is
usually marked halfway between the cricoid cartilage and the suprasternal notch. Inltration using local anaesthetic with adrenaline solution is
performed at the incision site
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Self-retaining retractors will help keep the skin incision open
(Fig.4.2). The strap muscles are separated vertically through
the linea alba and are retracted laterally by blunt dissection
(Fig. 4.3). The thyroid isthmus should be the next visible
anatomical structure of note. If access is adequate and the
isthmus is small, some surgeons prefer to dissect inferior to
the isthmus and create the tracheostomy opening there, with-
K. Muscat and S. Sood
Fig. 4.2 Surgical incision down to the investing layer of deep cervical
fascia. Self-retaining retractors can help keep the skin aps apart
Fig. 4.3 Strap muscles are identied, vertically divided along the linea
alba, and retracted laterally. Care is taken to avoid damage to the
anterior jugular veins
Fig. 4.4 The thyroid isthmus is identied and skeletonised with diathermy superiorly and inferiorly. A dissecting forceps is used to free it
from the underlying cricotracheal complex, and extensive diathermy is
used to divide it, to improve exposure in the surgical eld
out disturbing the thyroid isthmus itself. Our practice is
instead to skeletonise the thyroid isthmus and divide it using
clamps and transxion sutures, or using monopolar or bipolar diathermy [11] (Fig. 4.4). The advantage is that in the
case of dislodgement of the tracheostomy tube, the reinsertion is much faster and safer for the patient. The tracheal
anterior wall is exposed, coagulating any inferior thyroid
veins present (Fig. 4.5). The tracheostomy tube is opened
and its balloon is tested for any air leaks (Fig. 4.6). The
anaesthetist is advised to take control of the endotracheal
tube at the head of the table, and a square tracheal window is
excised from the third or fourth tracheal rings (Fig. 4.7).
Care is taken not to burst the endotracheal tube balloon and a
blunt cricoid hook is inserted at the top of the tracheostomy
window.
The anaesthetist is instructed to deate the cuff and retract
the tube slightly above the level of the tracheostomy window.
Suction is used to remove all secretions, and the lubricated
tracheostomy tube is inserted from one of the sides under
direct vision. Air is injected in the tracheostomy inatable
balloon. Sterile connection tubing is attached and the cricoid
hook and retractors are removed only after conrming the
presence of carbon dioxide trace on the monitor and after
conrming bilateral air entry into the chest. Only then is the
endotracheal tube completely withdrawn. The incision site is
checked for any bleeding, which should be controlled with
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Fig. 4.5 Upper tracheal rings are visualised by dissection. The surrounding soft tissue is excised or retracted laterally on both sides
Fig. 4.6 The chosen tracheostomy tube is checked and the tube balloon tested prior to doing any incision in the tracheal rings
Fig. 4.7 A small tracheal window is marked at the level of the third and
fourth tracheal rings. Excision of the cartilaginous segment follows.
Note the presence of the endotracheal tube visible through the window.
Haemostasis is ensured with bipolar diathermy set on low power. The
anaesthetist then deates the endotracheal tube cuff and retracts the
endotracheal tube until the tip is just above the tracheal window level
diathermy. It is then closed loosely to avoid surgical emphysema, and the tracheostomy tube is secured with sutures to
the skin and ties or velcro tapes (Fig.4.8). A tracheostomy
dressing is nally applied.
Fig. 4.8 The tracheostomy tube is inserted. If tube position is conrmed and haemostasis deemed sufcient, the retractors are removed
and the skin is closed. The tracheostomy tube is secured as a last step
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K. Muscat and S. Sood
Various key elements must be considered when performing such a procedure. One should anticipate procedures
made difcult by adverse anatomical factors, such as short,
thick necks or limited neck extension. In those cases, a wider
access incision and a surgical assistant for retraction are
essential. The procedure should be performed in a stepwise
fashion, taking time for meticulous haemostasis. Excess soft
tissue and fat can be excised out instead of just retracted. A
golden rule is always to palpate the structures at each level of
dissection (especially the cricoid cartilage, which is a cardinal landmark) and to stay in the midline to avoid damaging
vital structures, such as the great vessels of the neck. The
tracheal window can be performed with various techniques
as long as good results are reproducible. The position is more
important; doing it too high may damage the cricoid ring, but
doing it too low will create a very long and deep tracheal
tract that is difcult to manage. After inserting the tracheostomy tube, ensure that the surgical assistant holds the tube in
position with gentle pressure on the skin to avoid accidental
decannulation. When there is a large thyroid isthmus, adequate time should be used to excise it out and ensure
haemostasis. Alternatively, one can divide it centrally, dissect it, and suture the parts laterally and high to the strap
muscles.
4.4.2 Percutaneous Dilational Tracheostomy
A three-person team is usually needed to perform such a
procedure. One should be in charge of the ventilation and
sedation, the second will be in charge of the bronchoscopy,
and the third will be involved in performing the tracheostomy procedure itself. The tracheostomy kit should be
opened and it should be ensured that the team is familiar
with it. The patient is positioned with the neck maximally
extended using a sandbag or pillow beneath the shoulders.
The endotracheal tube is withdrawn slowly under exible
bronchoscopy vision to the level of the cricoid and is xed
in place. Local antiseptic solution is applied and sterile
draping is placed. Antibiotics are given according to local
hospital protocols. The key anatomical landmarks, such as
the thyroid and cricoid cartilages, are palpated, and the position of the cricoid cartilage can be marked. Any difculty in
identifying these landmarks or the detection of an abnormality, such as a large thyroid gland, is a relative contraindication to proceeding with the procedure. Inltration of local
anaesthetic with adrenaline solution is administered to the
skin and subcutaneous tissues below the inferior border of
the cricoid cartilage. A 2-cm incision is carried out slightly
below the cricoid cartilage, and blunt dissection is used,
aiming for the second tracheal ring (Fig. 4.9). Guided by
palpation, a needle is inserted through the incision, aiming
for the area under the rst or second tracheal ring, in the
midline (Fig.4.10). The correct midline position and level
are conrmed utilising a exible bronchoscope through the
endotracheal tube (Fig.4.11). Once satised, a guide-wire is
inserted through the needle into the tracheal lumen
(Fig.4.12). The needle is retracted, leaving the guide- wire
in position, and this is conrmed again using the same bronchoscopic technique (Fig.4.13).
Fig. 4.9 After palpation of
key landmark structures, such
as the thyroid and cricoid
cartilages, inltration using
local anaesthetic with
adrenaline solution is applied
to a small incision site. The
incision is carried out, and
blunt dissection is performed
slowly, aiming towards the
second tracheal ring
Fig. 4.10 After stabilising
the laryngotracheal complex
with one hand, a wide-bore
needle or trocar is inserted at
the site of the second tracheal
ring
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Fig. 4.11 On palpating the
tracheal ring, the angulation
of the trocar is changed to
point slightly caudal and the
anterior tracheal wall is
entered. Conrmation can be
obtained on aspirating air
within the mounted syringe,
and bronchoscopy will
conrm the site of entry
Fig. 4.12 Guide-wire
insertion through the trocar.
Steps are still monitored using
bronchoscopy through the
retracted endotracheal tube
53
Fig. 4.13 The trocar is
removed and the guide-wire is
left in situ
Fig. 4.14 The tract is opened
using a dilator over the
guide-wire, with steady
advancement and no lateral
rotation
The tract is then opened up using a single-stage wet dilator
with a lubricated tip, advancing it steadily with no lateral
rotatory movements (Fig.4.14). The dilator is then removed
and the lubricated tracheostomy tube is railroaded in over the
guide-wire (Fig.4.15). All these steps are done under the surveillance of the bronchoscope operator, to avoid and identify
early on any complications, such as damage to the posterior
tracheal wall. The tracheostomy tube cuff is inated
(Fig.4.16), the guide-wire is removed, and the tracheostomy
tube is connected to the ventilator machine. Once capnography shows an adequate trace and bilateral air entry is heard in
the lungs, the endotracheal tube can be deated and removed.
The tracheostomy tube is kept pressed onto the skin of the
neck and secured with sutures and ties or Velcro tapes.
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Fig. 4.15 Tracheostomy tube
being inserted through the
dilated tract over the
guide-wire as soon as the
dilator is removed
Fig. 4.16 Ination of cuff
and conrmation of tube
position; the tube is then
secured to the skin
K. Muscat and S. Sood
Various percutaneous tracheostomy kits are available on
the market, and one should be familiar with the ones available in the local setting. The basic steps are the same, but
there may be some additional steps or different types of
equipment that one should be aware of beforehand. The popularity and access to ultrasonography is increasing, and this
is also inuencing this tracheostomy technique. A rapid
ultrasound scan of the neck after positioning the patient will
show if there are any gross aberrant vessels lying in the midline and will also enable visualisation of the thyroid gland
and any of its abnormalities. The metal needle is also placed
in the tracheal wall using a linear ultrasound probe wrapped
in a sterile sheath, improving the accuracy of the insertion
and supplementing the bronchoscopic view. During insertion
of the needle, it is useful to attach it to a syringe lled with
saline. The insertion is done with the syringe under suction,
and the presence of air bubbles being drawn up will indicate
that the trachea has been entered. Needless to say, direct
bronchoscopic viewing is essential to avoid complications,
such as lateral tracheal entry and posterior wall laceration. It
is also essential that once the tracheostomy tube is inserted,
a dedicated person should keep it in position, pressed on the
skin of the neck, because the tract formed (unlike the tract
formed by the open surgical technique) is extremely unstable
and collapses the very moment the tube moves out of the
trachea. If doubts remain about the position of the tube, one
can also use the bronchoscope through the tracheostomy
tube to visualise the position in the trachea and the distance
from the carina.
4.5 Postoperative Care
A postoperative checklist is usually carried out by the clinician who performed the tracheostomy procedure, and proper
handover to the team in charge of the postoperative monitoring of the patient is ensured. Most of the content of this
checklist is the same whether the tracheostomy is carried out
using the percutaneous dilational technique or the standard
open surgical technique. The main focus is to ensure proper
routine tracheostomy care, with quick recognition of early
postoperative complications and avoidance of common mistakes in tracheostomy care.
It is good practice to perform a chest x-ray after any tracheostomy procedure to visualise the tube in relation to the
trachea and to inspect the lungs for any pathology, including
pneumothorax, collapse, or opacications. The patient is
usually nursed in the reverse Trendelenburg position to avoid
increased venous pressure that may lead to recurrent oozing
of blood from the wound. The various components of the
tracheostomy tube kit that are not being used on the patient,
such as insertion trocars and spare inner tubes, should be
sealed in a bag and given during a comprehensive handover
to the nursing staff taking care of the patient. The various
parts of the ventilation tubing should be in neutral position
and not pulling the tracheostomy tube laterally. The neck is
checked for any signicant surgical emphysema, which
could be attributed to the surgical incision site being closed
too tight. The neck ties should be tight enough to allow the
insertion of only one nger between them and the neck. The
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tracheostomy site is checked for any air leak, and the cuff
pressure is adjusted with the help of a cuff manometer. Cuff
pressures should not exceed 25 cm of water, as pressures
above that present a high risk of causing necrosis of the
mucosal lining [12]. If problems with leak are still present
despite adjusting ination pressures of the balloon, the tracheostomy tube should be replaced in a safe environment
with a larger size. Local infection may be prevented by
meticulous surgical technique and proper placement of the
tube, together with administration of antibiotics according to
the local hospital policy.
It is important that during the rst 24–48 hours, any
patient with a fresh tracheostomy must be monitored by
staff experienced in tracheostomy care. Adequate humidication is essential to avoid crust formation. Regular and
properly performed aseptic suctioning of secretions is necessary to avoid blockage of the tube and trauma to the upper
airways [12]. The use of double-lumen tubes reduces the
risk of blockage by secretions, as the inner cannula can be
cleaned as frequently as needed. Personnel should be trained
to recognise possible early complications, such as accidental decannulation, so as to alert expert help immediately,
before the situation deteriorates. Patients who have had
severe- grade upper airway obstruction can be susceptible to
acute pulmonary oedema and respiratory arrest. Again,
trained personnel should identify and treat such issues early
on. Postoperative bleeding in the early phase should be recognised, and there should be a low threshold to take the
patient back to the operating room for exploration [13].
Bleeding at this stage is usually coming from roughened
edges of the tracheal window, the thyroid isthmus, or the
inferior thyroid veins. Bleeding at a later stage should raise
the possibility of sentinel bleeds from erosion of the tube
through the trachea and possibly into the mediastinal great
vessels. This situation should be urgently and appropriately
investigated.
The timing of the rst tube change depends on whether
the patient is still dependent on the tracheostomy and on
what technique was used [14]. In the case of the percutaneous tracheostomy technique, it is usually advisable to wait
until at least 7days after the procedure. In such cases, and in
difcult open-tracheostomy patients with adverse anatomy,
one can do the rst tube change over a guide-wire or bougie
to avoid formation of a false passage. If dislodgement or
decannulation is suspected, exible endoscopy through the
tracheostomy tube can conrm its position. If the patient is
expected to start voice usage in the postoperative period, a
fenestrated tube should be inserted, and a non-fenestrated
inner tube is used until necessary.
Various decannulation protocols can be followed. One
can downsize the tube, plug it under close observation, and
monitor the situation with pulse oximetry. Another alternative, especially used for prophylactic tracheostomies after
complex head and neck surgery with reconstruction, is to do
a exible nasoendoscopy; if the vocal cords are visualised
and the airway is considered safe, the tracheostomy tube can
be removed without downsizing. The wound is covered with
an occlusive dressing until complete healing occurs.
Patients that require a long-term tracheostomy need training and rehabilitation in order to cope with routine daily tracheostomy care. Late complications, such as tracheal
stenosis, tracheomalacia, or a persistent tracheocutaneous
stula, should be kept in mind, as they may need further surgical management.
References
1. Pracy JP, Rogers M. Tracheostomy. In: Watkinson J, Gilbert RW,
editors. Stell & Maran’s textbook of head and neck surgery and
oncology. 5th ed. Boca Raton: CRC Press; 2012. p.273–80.
2. Au JK, Heineman TE, Schmalbach CE, St. John MA. Should
adult surgical tracheostomies include a Bjork ap? Laryngoscope.
2017;127:535–6.
3. Ciaglia P, Firsching R, Syniec C.Elective percutaneous dilatational
tracheostomy. A new simple bedside procedure; preliminary report.
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JM. Percutaneous tracheostomy—a new method. Crit Care Med.
1989;17:1052–6.
5. Fantoni A, Ripamonti D. A non-derivative, non-surgical tracheostomy: the translaryngeal method. Intensive Care Med.
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6. Byhahn C, Wilke HJ, Halbig S, Lischke V, Westphal K.Percutaneous
tracheostomy: Ciaglia Blue Rhino versus the basic Ciaglia technique of percutaneous dilational tracheostomy. Anesth Analg.
2000;91:882–6.
7. Higgins KM, Punthakee X.Meta-analysis comparison of open versus percutaneous tracheostomy. Laryngoscope. 2007;117:447–54.
8. Mehta C, Mehta Y.Percutaneous tracheostomy. Ann Card Anaesth.
2017;20(1):19–25.
9. Muscat K, Bille A, Simo R.A guide to open surgical tracheostomy.
Shanghai Chest. 2017;1:4.
10. Cheung NH, Napolitano LM. Tracheostomy: epidemiology, indications, timing, technique, and outcomes discussion. Respir Care.
2014;59:895–915; discussion 916–9.
11. Muscat K, Bille A, Simo R.A guide to open surgical tracheostomy.
In: Scarci M, Sihoe ADL, Bedetti B, editors. Open thoracic surgery,
vol. 1. Hong Kong: AME Publishing Company; 2017. p.112–7.
12. McGrath BA, Bates L, Atkinson D, Moore JA. Multidisciplinary
guidelines for the management of tracheostomy and laryngectomy
airway emergencies. Anaesthesia. 2012;67:1025–41.
13. Bradley PJ.Bleeding around a tracheostomy wound: what to consider and what to do? J Laryngol Otol. 2009;123:952–6.
14. White AC, Kher S, O’Connor HH.When to change a tracheostomy
tube. Respir Care. 2010;55:1069–75.
Tracheal andCricotracheal Resection
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andAnastomosis forSubglottic and/or
Proximal Tracheal Stenoses
DavideLancini, AlbertoPaderno, andCesarePiazza
5
5.1 Introduction
Laryngo-tracheal stenoses (LTS) represent rather rare clinical entities, which often constitute challenging situations for
anaesthesiologists, bronchoscopists, head and neck, and thoracic surgeons.
Since these conditions may heavily impact on patients’
quality of life, meticulous and detailed preoperative assessment should be carried out whenever possible, at least in an
elective scenario, in order to offer the best tailored treatment
strategy, which should always take place in referral centres,
which are best prepared to deal with these complex conditions. Surgeons approaching this type of problem need to be
trained in both endoscopic and open procedures, working in
strict contact with anaesthesiologists and other airway
specialists.
On the other hand, LTS can be the underlying cause of
dyspnoea in patients who reach any emergency department.
Therefore, treatment of these pathologies and its possible
consequences needs to be well known by all clinicians who
are potentially involved in the initial evaluation and emergent management of patients with such symptoms.
We herein illustrate the anatomy of the laryngo-tracheal
junction, the pathogenesis of LTS, classication of severity,
and treatment indications. Moreover, we propose our personal categorization of tracheal and crico-tracheal resection
and anastomosis procedures, describing their essential surgical steps, and postoperative management.
D. Lancini · A. Paderno · C. Piazza (*)
Unit of Otorhinolaryngology—Head and Neck Surgery, ASST—
Spedali Civili of Brescia, Department of Medical and Surgical
Specialties, Radiological Sciences, and Public Health University of
Brescia, Brescia, Italy
5.2 Anatomy oftheLaryngo-tracheal
Junction andProximal Trachea
The cricoid cartilage represents the only full-circle cartilaginous structure of the airway and its narrowest non- expandable
portion, supporting the entire laryngeal framework. This
hyaline cartilage constitutes the pivotal structure of the
laryngo-tracheal junction (LTJ) ) because of the following
reasons:
– The crico-arytenoid joints (CAJs) posteriorly and the
conus elasticus laterally are inserted to the superior margin of the cricoid lamina.
– The crico-thyroid membrane is inserted to the anterior
edge of the ring.
– The intrinsic laryngeal muscles (lateral and posterior
crico-arytenoid and crico-thyroid muscles) are attached to
the external circumference of the cartilage.
– The recurrent laryngeal nerves (RLNs) enter into the lar-
ynx laying adherent to the postero-lateral wall of the cricoid lamina, postero-medial to each crico-thyroid joint, in
between the inferior cornu of the thyroid lamina and the
CAJ, covered by the crico-pharyngeal muscle, but supercial to the posterior crico-arytenoid muscle (Fig.5.1).
– The crico-tracheal membrane is attached to the inferior
margin of the cricoid and connects it to the rst tracheal
ring [1–5].
The trachea has a tubular structure made of 18–22 cartilaginous hyaline half-rings, completed posteriorly by a
membranous (party) wall, which connects the organ to the
anterior surface of the esophagus. An elastic membrane fullls the space between adjacent rings. The thyroid gland is
attached through the Berry’s ligament to the antero-lateral
aspect of the rst 2–3 tracheal rings. The RLNs run bilaterally in the tracheo-esophageal grooves, with a more vertical
and dorsal course on the left, due to its origin below the aortic arch on this side. The innominate artery leans on the ante-
© Springer Nature Switzerland AG 2024
R. Simo et al. (eds.), Atlas of Head and Neck Surgery, Springer Surgery Atlas Series,
https://doi.org/10.1007/978-3-031-36593-5_5
57
58
muscle
CP
C
muscle
CP
A
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CT muscle
CT muscle
C
C
muscle
muscle
Fig. 5.1 Axial section of the upper aerodigestive tract at the level of the
cricoid cartilage, passing through the crico-thyroid (CT) joints. Note
the relationships of the recurrent laryngeal nerve (RN) with the inferior
cornu of the thyroid cartilage and the CT joint, the crico-pharyngeal
(CP) and the posterior cricoarytenoid (PCA) muscles. C cricoid cartilage, CP crico-pharyngeal muscle, CT crico-thyroid joint, PCA posterior crico-arytenoid muscle, RN recurrent laryngeal nerve, UES upper
esophageal sphincter
Mucosa
Mucosa
CT joint
CT joint
RN
RN
PCA
PCA
UES
UES
rior tracheal wall while crossing it at the level of the superior
mediastinal inlet. In contrast, the brachio-cefalic vein usually
lies more supercially and cranially to the artery, not in
direct relationships with the airway.
The inferior thyroid artery (ITA) is the major contributor
to the vascularization of the LTJ and proximal trachea. The
crico-thyroid artery, branch of the superior thyroid artery
(STA), vascularizes the subglottis, making an anastomotic
network with the intralaryngeal submucosal branches of the
superior laryngeal artery (Fig.5.2) [6]. As reported by Grillo,
the proximal tracheal vascularization is guaranteed by three
branches of the ITA, while the middle and distal tracheal
portions are variably supported by branches of the supreme
intercostal, subclavian, internal thoracic, brachiocephalic,
and bronchial arteries [7]. All these vessels constitute a segmental system in which a single artery gives possible support
D. Lancini et al.
Epiglottis
ea1
EA
PIA
ea2
AIA
PC
SLA
Arytenoid
(everted)
Fig. 5.2 Midline sagittal section of the larynx, after partial removal of
left supraglottic structures and vocal fold, showing the intralaryngeal
vascular network (originating from the superior thyroid artery) and its
anastomosis with the crico-thyroid artery (originating from the inferior
thyroid artery). SLA superior laryngeal artery, EA epiglottic artery (dotted lines ea1 and ea2 represent the landmark points used for measurements of the EA in Perotti etal. [6]), AIA antero-inferior artery, PIA
postero-inferior artery, PCA paracommissural branch of the crico–thyroid artery
to a number of tracheal rings and longitudinally anastomizes
on the external surface of the trachea with the superior and
inferior homologues. From such a plexus, the intercartilaginous branches cross the membranes to reach the submucosa where a microvascular network is present. Tracheal
rings are supported only by this delicate submucosal plexus,
which is prone to compression against the external cartilaginous framework by endoluminal foreign bodies (especially
endotracheal tubes, tracheotomic cannulae, and cuffs)
(Fig.5.3).
Mucosal perfusion
5 Tracheal andCricotracheal Resection andAnastomosis forSubglottic and/or Proximal Tracheal Stenoses
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Fig. 5.3 Representation of
the tracheal submucosal
vascular plexus and
theoretical relationships
between percentages of
mucosal blood perfusion and
endotracheal tube cuff
pressures as measured in cm
H
O
2
59
100%
50%
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5.3 Pathogenesis ofLaryngo-tracheal
Stenoses
Prolonged invasive ventilation by means of endotracheal or
trans-tracheal tubes is the most common cause of laryngotracheal stenoses (LTS). In fact, in case of excessive pression
over time, and in patients prone to an altered healing process
due to various comorbidities such as diabetes and cardiovascular problems, the ischemic-necrotic injury caused by endoluminal compression may lead to potentially irreversible
pathologic changes of the airway framework. This usually
starts with a mucosal ulcer and associated overgrowth of
granulation tissue, collagen deposition, and neoangiogenesis, which can organize itself in a brous scar. At
the level of the posterior commissure and inter-arytenoid
region, this phenomenon may carry to chondritis and, eventually, xation of one or both the CAJs. The same chondritis
may cause necrosis and malacia of different airway segments
Normal perfusion of the tracheal mucosa
Usual range of ETT cu pressure
Initial mucosal ischemic alterations
Arteriolar compression and mucosal
ischemic damage
ETT cu pressure (cmH
O)
2
(i.e. cricoid plate, arch or tracheal rings) with further collapse of the lumen under the negative pressures generated by
exertional respiration.
As general rules, the smallest endotracheal tube allowing
a safe ventilation of an intubated patient should be applied,
with cuff pressure frequently monitored in order not to
exceed 20–30cm H
O and, if possible, deep sedation should
2
be maintained to reduce the risk of self-inicted airway
trauma during episode of agitation while intubated. Crucially,
in case of expected long-term oro-tracheal intubation, a tracheostomy should be performed within 7–10days from initial intubation. Even though in the literature no general
consensus has been reached regarding the safest and least
invasive tracheostomy technique, good clinical practice
should be aimed at reducing the tracheal trauma by positioning the airway opening at least 1–2 tracheal rings below the
cricoid arch, and making it as small as the external diameter
of the tracheotomic cannula to be inserted. Judicious use of
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