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Tracheostomies
22
The continued application of PEEP is important during transport from the ICU
to the operating room. Based on the assessment, the anesthesiologist must decide whether to choose a direct laryngoscopy, an awake fiberoptic intubation, or
a tracheotomy under local anesthesia to secure the airway. Often, these patients
have a long history of smoking, with consequent chronic obstructive pulmonary
disease (COPD). If symptoms of worsening pulmonary function are present,
helpful preoperative testing includes pulmonary function tests (PFT) and arterial blood gases.
ence of any symptoms with exertion. If the patient reports incapacitating dyspnea, chest pain, or light-headedness with climbing more than two flights of
stairs or on occasion at rest, then further testing is indicated, including a stress
test or even a coronary angiography. Pre-existing risk factors include smoking,
alcohol abuse, male gender, hypercholesterolemia, hypertension, and a family
history of cardiovascular disease.
abnormal coagulation, especially in cases of malignancy or chronic disorders.
Preoperative laboratory data should survey a complete blood count, prothrombin time (PT), activated thromboplastin time (PTT), and platelet count. Any
existing preoperative neurologic deficits should be documented clearly. Finally,
the patient should have nothing by mouth for at least 6 hours prior to the procedure. Similarly, enteral feeding via a nasogastric tube should be stopped 6 hours
prior to the tracheostomy procedure (Brown, 1996).
The most valuable cardiovascular history is exercise tolerance and the pres-
Hematologic profiles are also essential to exclude conditions of anemia or
Premedication
Standard premedication for elective cases is an anxiolytic benzodiazepine, most
commonly midazolam (approximately 2 mg IV). However, premedication is best
avoided if the airway is compromised or in emergency procedures.
Anesthetic Technique
The anesthetic technique of choice for tracheotomy is general anesthesia with
endotracheal intubation.
Equipment and Monitoring
The ASA (American Society of Anesthesiologists) standard monitoring is used
and includes continuous pulse oximetry, capnography, and electrocardiography
(ECG), along with frequent blood pressure measurements (every 3–5 minutes).
For patients with critical end-organ dysfunction (neurologic or cardiovascular),
arterial blood pressure should be used for closer monitoring. Peripheral intravenous access must be ensured with the placement of, at minimum, a 20-gauge
intravenous catheter that infuses well.
A preprocedure patient safety checklist for bedside tracheotomies in the ICU
is provided in Table 2.3 for reference. Low FiO
electrocautery is needed during surgery, can be maintained by using a regulator for mixing oxygen and air to target FiO
, which avoids airway fires when
2
around 30% oxygen concentration
2
Chapter 2 Tracheotomy Procedure
Bedside Tracheostomy Preprocedure Checklist
2.3
Members Present
Surgeon: ■
Anesthesiologist: ■
RN: ■
Key Elements
Patient is stable to undergo procedure at this time. ■
Bipolar vs. monopolar cautery has been considered. ■
Both CO ■
responsible person has been outlined to the team.
Main O
■
been outlined to the team.
Skin antisepsis: product is confirmed alcohol-free.
■
Drape does not cover mouth, endotracheal tube, or ambu bag. ■
FiO ■
Time Out has been performed and documented.
■
and ABC fire extinguishers have been located with their triggers, and the
2
gas shut-off valve in the ICU has been located, and the responsible person has
2
level has been coordinated with electrocautery.
2
23
while ensuring the patient’s blood oxygen saturation stays at a minimum of 94%
or higher (see Figure 2.1).
Induction
If already intubated, preexisting sedation should be converted to general anesthesia using carefully titrated induction agents. If not intubated and no airway
problems are anticipated, a standard induction may be appropriate. If airway
problems are anticipated, an awake fiberoptic intubation is the method of
choice. In any event, the anesthesiologist should be prepared to deal with a
failed intubation and must have a surgeon immediately available to perform a
tracheotomy if ventilation proves impossible.
A popular regimen is propofol for hypnosis and fentanyl for analgesia, in
addition to a muscle relaxant to keep the patient immobile during the surgical
procedure, particularly at the point of tracheotomy.
Induction: Propofol 1–1.5 mg/ kg
Muscle relaxation: Succinylcholine 1.5–2 mg/ kg if a difficult intubation is
anticipated (half-life is 5 min); if a difficult intubation is not anticipated,
a nondepolarizing muscle relaxant such as rocuronium can be administered at a dosage of 0.6 mg/kg (half-life is 20–30 min)
Maintenance
The simplest maintenance is to administer a hypnotic, an analgesic, and a muscle relaxant.
Tracheostomies
24
2.1
The O2 regulator can be adjusted to dial the FiO2 (in %) up or down depending on the use of
electrocautery and patient oxygen requirements. An oxygen analyzer is used to calibrate
the concentration of oxygen from the O
through a humidifier to a resuscitation ventilation bag, which the anesthesiologist uses to
deliver manual breaths in concert with surgical maneuvering. A capnograph must be used
as a standard monitor for tracheotomy procedures to confirm adequate ventilation and
access to the upper airway.
regulator. An air/O2 gas mixture is delivered
2
Propofol infusion: 40–100 mcg/kg/min
Fentanyl infusion: 3 mcg/kg/hr, or a total of approximately 250 mcg for the
entire procedure (it is helpful to administer the fentanyl a few minutes
before the surgeon enters the trachea, which, in general, is the time of
highest stimulation); a fentanyl dose of 150–200 mcg IV can ablate a significant increase in intracranial pressure in patients with intracranial
hypertension and presumed loss of autoregulation of cerebral blood flow
with intracranial pathology
Fluid requirements average 1–2 ml/kg/hr for the entire procedure, and
blood loss is minimal, particularly when tracheotomy is done as an isolated
procedure.
A rigid bronchoscope should be available to reestablish the airway in case
of a failed reintubation. Alternatively, a large-bore airway exchange catheter
Chapter 2 Tracheotomy Procedure
can be advanced through the bronchoscopy elbow adapter attached to the
existing ETT prior to tracheostomy tube insertion in patients at high risk for
failed reintubation. Frequently, when tracheostomy is a prelude to a more major
procedure, an anode tube is inserted through the tracheostomy and sutured in
place. It is replaced at the end of surgery by a cuffed tracheostomy tube.
Emergence
Besides analgesia, surgical site hemostasis, and adequate gas exchange, there
are no special considerations for emergence following tracheotomy. Opioid sedation and analgesia will blunt any reactions to suctioning in the early postoperative period.
Complications
Postoperative surveillance for complications should look for pneumothorax,
hemorrhage in the form of an obstructing hematoma, aspiration of blood, loss
of airway requiring reintubation, difficult endotracheal tube reinsertion, and
pneumomediastinum. Pneumothorax may also occur with low neck dissection.
A postoperative chest radiograph will define the position of the tracheostomy
tube and survey for the presence of pneumothorax or pneumomediastinum.
25
Surgical Technique
The surgical technique for tracheotomy has evolved throughout history. The division of the thyroid isthmus was first described by Degarengot in 1720 (Grillo,
2003). Tracheotomies continued to be performed high; because of the relative
speed and ease of this approach, this practice was not altered until 1909, when
Jackson described the increased rates of subglottic stenosis associated with high
tracheotomy placement. Today, many variations in technique are still commonplace. Current technique can nonetheless be divided into two broad categories:
the open surgical approach and percutaneous dilatational tracheotomy.
Surgical Anatomy
The sternal notch and thyroid and cricoid cartilages are usually easily palpable through the skin. A key surface landmark, the cricoids, is usually found by
using the thyroid cartilage above and the sternal notch below as reference
points. The cricothyroid membrane spans the anterior aspect of the thyroid and
cricoid cartilages. It is identified by palpating a slight indentation in the skin inferior to the thyroid notch. The paired cricothyroid arteries traverse horizontally
along the superior aspect of this membrane and anastomose in the midline.
The cricothyroid muscles arise from the anterior surface of the cricoid and
extend superiorly and posteriorly to attach to the lateral surfaces of the thyroid
alae. The innominate, or brachiocephalic, artery crosses from left to right, just
anterior to the trachea at the superior thoracic inlet and deep to the sternal
notch. Its pulsations are often felt during dissection of the anterior tracheal
wall. The trachea is comprised of 18 to 22 semicircular cartilaginous rings and is
Tracheostomies
26
posteriorly separated from the esophagus by a membranous portion. The average width of the tracheal lumen is 2.3 cm in the coronal dimension and 1.8 cm
in the sagittal dimension. The average length of the adult trachea is 11 cm, with
a range of 12 to 15 cm.
laterally, and the isthmus crosses it anteriorly at the level of the second to fourth
tracheal rings. The endocrine tissue is highly vascular and must be handled
carefully to prevent bleeding. The recurrent laryngeal nerves and inferior thyroid veins travel in the tracheoesophageal grooves and are out of the surgical
field unless dissection strays significantly. The great vessels, too, are lateral to
the intended dissection and should be avoided.
Open Tracheotomy
The open surgical tracheotomy can be performed in the operating room or at
the bedside in a monitored setting such as the ICU. The procedure is most commonly performed under general anesthesia in a previously intubated patient.
Occasionally, when the patient presents in acute distress, the procedure is performed in the nonintubated patient under local anesthesia, while the patient
breathes spontaneously.
shoulders to extend the neck and expose the laryngotracheal landmarks (Figure 2.2A). This maneuver is contraindicated in patients with cervical spine injuries or atlantoaxial instability, as seen in Trisomy 21 syndrome, where neck
extension can result in spinal cord compression. Certain patients with tenuous
airways may not be able to tolerate either neck extension or even the supine
position, requiring tracheotomy to be performed with the patient in a sitting position without neck extension. Patients with significant kyphoscoliosis, cervical
osteoarthritis, or other conditions in which the neck cannot be hyperextended
can present a significant technical challenge.
cluding the thyroid cartilage, cricoid cartilage, and sternal notch. A marking pen
can be used to indicate the relative position of each of these crucial landmarks
on the skin of the extended neck (Figure 2.2B). Lidocaine (usually 1% with a
1:100,000 dilution of epinephrine) is injected into the skin and subcutaneous
tissues where the incision will be placed. The neck and upper chest are prepared in povidone-iodine (Betadine) solution, and the surgical site is draped
to allow easy access to the oral cavity so the endotracheal tube can be easily mobilized and manipulated by the anesthesiologist during the procedure. A
critical precaution involves avoiding the use of Bovie cautery in the presence
of alcohol-based surgical prep solution (DuraPrep). The risk of surgical fire
associated with the incomplete drying of this agent in the context of electrosurgical procedures has been described previously (Weber, Hargunani, & Wax,
2006). Particular risks are associated with head and neck operations when an
oxygen-enriched atmosphere can develop under the surgical drapes. This is a
significant risk during the use of oxygen-rich gas delivery from nasal cannulas
or ventilation masks when the procedure is performed on the awake, spontaneously breathing patient. The use of electrocautery in these circumstances constitutes a significant hazard.
The thyroid gland lies anteriorly to the trachea with each thyroid lobe lying
The patient is placed on the operating table with a bolster underneath the
The procedure begins with the palpation of the landmarks of the neck, in-
Chapter 2 Tracheotomy Procedure
A 2–3 cm incision is carried out in a vertical or horizontal fashion (Figure 2.3). The horizontal incision provides a more cosmetically pleasing postoperative scar, as it follows the relaxed skin tension lines. This benefit decreases,
however, the longer the tracheostomy remains in place. Vertical incision avoids
the anterior jugular venous system, therefore minimizing cumbersome bleeding in cases of emergency tracheotomies. Vertical incisions start just below
the cricoid cartilage, whereas horizontal incisions are made either two finger’s
breadths below the cricoid cartilage or halfway between the cricoid cartilage
and the sternal notch, typically over the interspace between the second and
third tracheal rings. The subcutaneous tissues are then divided with either a 15
blade or Bovie electrocautery to the level of the strap muscles. Care should be
exercised at this stage to avoid damage to the anterior jugular vein, which, when
identified, should be lateralized or ligated in order to avoid unnecessary bleeding. Once identified, the strap muscles should be divided vertically along their
midline raphe until the thyroid isthmus is exposed (Figure 2.4).
2.2
27
Surgical tracheotomy preparation.
(A) Patient positioning with roll
under shoulders. (B) Surface
landmarks showing the thyroid,
the cricoid, the intended location of
the skin incision, and the anterior
border of the sternocleidomastoid
muscle.
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28
2.3
Surgical tracheotomy
procedure. (A) Initial incision.
Note the anterior border of the
sternocleidomastoid muscle.
(B) Incision with spreaders.
The thyroid gland can be handled in a number of ways. Depending on the
location of the isthmus within the surgical wound, the isthmus can be retracted
superiorly, inferiorly, or divided and ligated to expose the second and third
tracheal rings, where the tracheal window will be performed (Figure 2.5). The
cricoid cartilage serves as an important landmark during this portion of the
dissection. Often, traction placed on the cricoid cartilage using a cricoid hook
mobilizes the laryngotracheal complex into more favorable, superior, and superficial position to allow easier access into the trachea.
The pretracheal fascia is dissected off the proximal trachea using a Kitner
sponge. With patients having tracheotomy under local anesthesia, it is important to inject local anesthetic into the pretracheal tissues prior to opening the
trachea in order to provide proper analgesia. In addition, a 2% lidocaine solution
can be applied transtracheally to obtain topical endoluminal anesthesia. There
are multiple incision types for entrance into the trachea. Some surgeons prefer
a single horizontal intercartilaginous incision, while others perform an H-type
incision or make a tracheal window by removing a centimeter-wide portion of
Chapter 2 Tracheotomy Procedure
2.4
Surgical tracheotomy procedure. (A) Exposure of the thyroid isthmus. Note the thyroid
isthmus is exposed over the proximal trachea. (B) The thyroid isthmus is cross-clamped
and divided.
29
the anterior aspect of the second or third tracheal ring. The type of incision does
not seem to affect the development of postoperative tracheal stenosis in either animal models (Natvig & Olving, 1981; Whitley, Castillo, Hassett, Banyas, &
Luchette, 1997) or humans. An inferiorly based trap door flap (Bjork flap) can
be created by incising the interspace between the second and third tracheal
rings as well as the third tracheal ring laterally on both sides, extending inferiorly from the interspace incision. The superior aspect of the flap is then sutured
to the inferior aspect of the skin incision with a nonabsorbable suture. This flap
facilitates reinsertion of the tracheostomy tube in cases of accidental decannulation, especially in obese patients or those with difficult anatomy. Despite
commonly expressed concerns, a study by Malata, Foo, Simpson, and Batchelor
(1996) suggests there is no increased rate of either tracheostenosis or tracheocutaneous fistula with use of the Bjork flap. Another option for managing the
anterior tracheal wall is the removal of an anterior section of the second or
third tracheal rings using a scalpel, Metzenbaum scissors, or tracheal punch.
Once the trachea is entered, a tracheotomy dilator is used to optimize exposure to the tracheal lumen, taking care to prevent excess trauma to the cartilaginous framework of the trachea. Upon visualization of the endotracheal tube
within the lumen, the anesthesiologist is asked to withdraw the tube until the
posterior tracheal wall is visualized. The tracheostomy tube is then introduced
into the lumen of the trachea under direct visualization. In cases of patients with
a history of difficult intubation, the endotracheal tube can be withdrawn over a
tube exchanger to facilitate reintubation in case tracheostomy tube placement
Tracheostomies
30
2.5
Surgical tracheotomy procedure. (A) Removing tracheal ring to form window. (B) Stay
sutures are placed superiorly and inferiorly to the stoma.
proves difficult. After introduction of the tracheostomy tube, proper placement
should be confirmed before the endotracheal tube is removed. This is done by
detecting carbon dioxide return from the tracheostomy tube and then suctioning the tracheal contents with a flexible suction catheter. If proper placement
of the tracheostomy tube cannot be confirmed via these steps, the endotracheal
tube should be reintroduced by the anesthesiologist. Once successfully placed,
the tracheostomy tube should be secured into place with nonabsorbable sutures
placed through the flanges of the tube (Figure 2.6) as well as tracheostomy ties
placed around the patient’s neck.
Percutaneous Dilatational Tracheotomy (PDT)
In 1953, Seldinger (1953) introduced the technique of percutaneous guide wire
needle placement in arterial catheterization. Soon the guide wire technique,
now known as the Seldinger technique, was adapted to various procedures,
Chapter 2 Tracheotomy Procedure
2.6
Neck flange sutured in place.
31
including percutaneous tracheotomy. The first modern percutaneous dilatational tracheotomy (PDT) was reported by Shelden, Pudenz, Freshwater, and
Crue (1955) in 1955, but the complication rate was very high due to the laceration of adjacent structures by the trocar. In 1969, Toy and Weinstein (1969) developed a tapered straight dilator with a recessed cutting blade for performing
percutaneous tracheotomy over a guiding catheter. The technique of PDT using
serial dilators over a guide wire was first described in 1985 by Ciaglia, Firshing,
and Synlec (1985). In 1989, Schachner and colleagues developed a dilating tracheotomy forceps over a guide wire. In 1990, Griggs, Worthley, Gilligan, Thomas,
and Myburg developed another guide wire dilating forceps specifically for percutaneous tracheotomy. Shortly thereafter, convenient kits to create a full-sized
percutaneous tracheotomy became readily available.
PDT involves the placement of a tracheostomy tube without direct visualization of the trachea. The general consensus is that PDT should only be performed
on intubated patients. It is considered to be a minimally invasive procedure that
can be performed at the bedside in monitored settings. Bronchoscopic guidance
is considered the standard of care, and a single surgeon or intensivist aided by
a bronchoscopist can easily accomplish the procedure. The main benefit derived from direct bronchoscopic visualization during PDT is close, real-time