Page 579 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 46: Tracheostomy 399

TECHNIQUE OF TRACHEOSTOMY the procedure has recently been described, but whether this will lead to
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reduced complications is uncertain.
36,37
The tracheostomy procedure inevitably leads to an interruption in ■ TECHNIQUE OF SURGICAL TRACHEOSTOMY
GENERAL CONSIDERATIONS
delivery of positive-end expiratory pressure (PEEP). This loss of PEEP The patient is positioned supine, with both arms tucked at the sides. If
can lead to important derecruitment of lung segments and atelectasis possible, a roll should be placed transversely beneath the shoulders to
and resultant desaturation and hypoxemia, especially among patients extend the neck, and a doughnut should be used to support the head.
with severe respiratory failure. We therefore recommend deferring or Positioning the patient in reverse Trendelenburg position may help to
postponing the procedure among patients requiring greater than 10 cm decrease any venous bleeding encountered. The sternal notch and cricoid
H O of PEEP, or among patients that have demonstrated oxygen desatu- cartilage are then palpated and marked. The incision is made horizontally
2
ration with minor changes to their current levels of PEEP or fraction of midway between these two landmarks. Infiltration with local anesthetic
inspired oxygen. containing epinephrine prior to incision may help to reduce skin-edge
Serious bleeding during the procedure is uncommon, but any impor- bleeding. Some authors favor a vertical incision, particularly in patients
tant coagulopathies or thrombocytopenia should be corrected. Loss of whose landmarks are difficult to palpate, or in emergency situations, stat-
airway is also uncommon, but the procedure should only be performed ing that greater flexibility is maintained and that bleeding is minimized
in the presence of individuals with advanced airway skills, and when by remaining in the avascular midline. However, the cosmetic result of
performing tracheostomy at the bedside, arrangements should be in a vertical neck incision is less acceptable. The subcutaneous tissues and
place to accommodate the need for an operating room and surgical platysma are divided until the strap muscles are identified. These are
expertise in the event of an airway emergency. Finally, tracheostomy is divided vertically in the midline and the straps retracted laterally. At this
contraindicated in patients with unstable cervical spine injuries. point, the thyroid isthmus is generally identified overlying the trachea.
■ SELECTION OF TECHNIQUE Depending on the exposure, the isthmus may be retracted either cephalad
or caudad or, most commonly, dissected off the underlying trachea and
Practitioners generally must select between performing a standard, divided between ties. With the trachea now exposed, the tracheal rings
are palpated and the second to fourth ring is selected for the tracheotomy.
surgical tracheostomy or a percutaneous dilational tracheostomy. Both
techniques may be performed either at the bedside in the ICU or in the Stay sutures are placed on either side of the tracheotomy site to facilitate
retraction of the trachea. At this point it is important to ensure complete
operating room, although the most common practice is for percutaneous
dilational tracheostomy to be performed in the ICU and surgical trache- hemostasis, as the surgical field will be obscured once the tracheotomy
tube is inserted. The tracheostomy tube should be prepared at this point,
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ostomy to be performed in the operating room. Percutaneous dilational
7
tracheostomy performed in the ICU is appealing for a number of reasons, and the cuff tested. The anesthesiologist then deflates the cuff of the
endotracheal tube and the tracheotomy incision is made. A blade should
in particular decreased costs and increased convenience ; the expense
29
of operating room time and personnel are eliminated, delays while be used, as the use of electrocautery risks an endotracheal fire with high
fractions of inspired oxygen. There are numerous conformations of tra-
39
awaiting operating room availability are avoided, and the patient is not sub-
jected to the risks of transportation from the ICU to the operating room. cheotomy incisions described. A vertical incision in the tracheal midline
works well and has a lower risk of tracheal cartilaginous complications
The ability to perform percutaneous dilational tracheostomy depends 40
on the ability to palpate surface landmarks and caution should be exer- compared to flaps. A horizontal incision between tracheal rings also has
a low incidence of cartilage damage. The Bjork flap is a trapdoor-like flap
cised when considering the procedure for patients with distorted neck
anatomy, morbid obesity, or a previous neck incision. While serious of anterior tracheal wall which may be sewn to the skin or superficial tis-
sues to help create a mature tract in case of accidental tube dislodgement.
bleeding is rarely encountered, when it does occur it can be more dif-
ficult to control because of the more limited visibility obtained at per- However, in addition to a greater degree of cartilage removed, which may
increase the incidence of tracheal stenosis, the flap itself may serve as a
cutaneous dilational tracheostomy compared to surgical tracheostomy.
Patients with a history of cervical spine injuries are also likely better means of tracheal or stomal obstruction if the tube needs early replace-
ment. Once the tracheotomy incision is made, the endotracheal tube is
41
treated with surgical tracheostomy because of the pressure on the neck
required to pass the dilator during the percutaneous approach. Also, the withdrawn under direct vision to a point just above the tracheotomy. The
tracheostomy tube is then inserted and the cuff inflated. Proper position-
inability to hyperextend the neck may limit the identification of land-
marks during percutaneous dilational tracheostomy. ing is ensured by direct visualization of the tube placement as well as by
the return of carbon dioxide once hooked up to the anesthetic machine.
The reported overall risk of procedural complications with the two
approaches has been similar in large cohort studies. However, in most The stay sutures in the trachea are left in place and can be secured to the
patient’s chest to allow for anterior traction on the trachea in case of tube
of these studies, patients considered to be at higher risk received surgi-
cal tracheostomies. There is likely a greater risk of postoperative stomal dislodgement. The skin is loosely approximated around the tracheostomy
tube. The tracheostomy tube itself may be secured to the skin with sutures
infection, and of significant postoperative bleeding with surgical
7,30
tracheostomy compared to percutaneous tracheostomy. There are little or secured only with the tracheostomy tube ties.
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data available comparing the long-term outcomes of the two approaches, ■
including rates of airway complications such as tracheal stenosis. TECHNIQUE OF PERCUTANEOUS DILATIONAL TRACHEOSTOMY
Percutaneous dilational tracheostomy does introduce a set of compli- Several techniques are described in the literature for performing per-
cations that were formerly extremely rare with surgical tracheostomy. cutaneous tracheostomy. The most common technique employed in
Most notable amongst these are damage to the posterior tracheal wall North America today is based on the dilational method, which Ciaglia
potentially resulting in tracheoesophageal fistula, and creation of a described in 1985. Ciaglia performed the technique using sequential
32
42
false passage by placement of the tracheostomy tube anterior or adjacent nephrostomy dilators, whereas today a single dilator has now been widely
to the trachea. The risk of both of these complications can be mini- adopted (described below). Other techniques of percutaneous tracheo-
33
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mized by performing percutaneous dilational tracheostomy under direct stomy include Fantoni’s translaryngeal method, where the guidewire is
44
bronchoscopic vision. Although percutaneous dilational tracheostomy retrieved through the endotracheal tube and a tracheostomy tube passed
34
without bronchoscopy is described in the literature and practiced in retrograde through the larynx and out through the anterior tracheal wall.
some centers, it is our view that percutaneous dilational tracheostomy This technique was devised to protect the posterior wall of the trachea
35
should always be performed under direct bronchoscopic visualization. from the sometimes substantial posterior force required with percu-
The use of ultrasound to help further delineate neck anatomy before taneous dilational tracheostomy, but is a more complex procedure to
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