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64 Bronchoscopy
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Flexible bronchoscopy allows for examination down to
1
the subsegmental level. Usually, these procedures are
performed in a specially designed endoscopy suite. The suite
should include a supplemental oxygen supply, pulse oximetry, cardiac monitoring and intubation equipment in the
event of an airway emergency. In our practice most of the
awake outpatient bronchoscopy is performed by the pulmonologists. The thoracic surgeon is usually involved in difficult
cases or those in which an untoward event has occurred. On
the other hand, all awake bronchoscopy performed in the
postoperative period on our ward is done by the thoracic surgeon. The most common indication is atelectasis due to
mucus plugging in the postoperative period. A well-timed
therapeutic bronchoscopy in the postoperative patient with
mucus plugging can avoid more serious complications such
as pneumonia and reintubation.
Rigid
Flexible
1
Flexible bronchoscopy under general anesthesia is performed in the operating room after the patient is anesthetized. If examination of the upper portions of the trachea
is required, the patient can be mask ventilated initially and
then intubated over the bronchoscope after the proximal
airway has been examined. Following intubation, the patient
can be ventilated through the endotracheal tube with use of
a bronchoscopy adapter while the remainder of the distal
airway examination is completed. Flexible bronchoscopy
allows examination of the airways down to the subsegmental level.
Rigid bronchoscopy
Rigid bronchoscopy is performed in the operating room
under general anesthesia. A number of specific applications
exist for rigid bronchoscopy which are listed in Table 7.2.
Table 7.2 Indications for rigid bronchoscopy
Removal of foreign bodies
Evaluation of tracheal stenosis
Placement of nonexpandable stents
Control of massive hemoptysis
Evaluation of tracheobronchial mobility
Evaluating airway invasion or adherence by esophageal tumors
Palliation of airway obstruction by tumor (“coring out”)
Ventilating rigid bronchoscopes have a side port adapter
2
to allow for connection to the anesthesia circuit. A venturi apparatus should also be available to provide oxygen
insufflation in the event that a nonventilating scope is used.
2
Anesthesia 65
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PREOPERATIVE ASSESSMENT AND
PREPARATION
General considerations for bronchoscopy
The initial evaluation of the patient begins with a complete
review of their medical and surgical history. Identification of
medical issues which will alter the conduct of the procedure,
such as bleeding dyscrasias or significant allergy to an anesthetic agent, is important. All recent radiographic studies
should be reviewed and the appropriate method of bronchoscopy (rigid, flexible, or both) selected. Prior to performing any procedure, we have a detailed discussion with the
patient and family concerning the risks and benefits of the
procedure. Except in truly emergent situations, we always
obtain a signed permit prior to the procedure.
Flexible bronchoscopy
We provide supplemental oxygen to all patients undergoing
bronchoscopy. For awake bronchoscopy, oxygen is provided
either via a nasal cannula or by a face mask with an opening
to allow for the passage of the bronchoscope. Monitoring in
the awake patient should include pulse oximetry and heart
rate at a minimum. Most patients have an intravenous line in
place; however, with properly administered topical anesthesia
intravenous sedation is rarely required. We perform awake
bronchoscopy on an outpatient basis in the bronchoscopy
suite and on an inpatient basis on the general patient wards.
On the inpatient ward, we maintain bronchoscopy carts in
conjunction with the respiratory therapists. These carts are
stocked with a flexible bronchoscope, a light source, suction
tubing, bite blocks, oxygen masks, local anesthetics, pulse
oximetry, and emergency airway equipment. These simple
carts minimize the frustration encountered when performing
a procedure on an awake patient without all the appropriate
equipment available. We use a standard adult bronchoscope
with an external diameter of 5.9 mm for these procedures.
Flexible bronchoscopy under general anesthesia is performed in the operating room in conjunction with an
anesthesiologist. Monitoring includes pulse oximetry, noninvasive blood pressure monitoring, and three-lead electrocardiogram (ECG) monitoring. Following the induction of
general anesthesia, direct laryngoscopy is performed and an
endotracheal tube is placed. Tube position is confirmed by auscultation, observation of the chest, and end-tidal carbon dioxide monitoring. In the adult patient we like to place an 8.0 mm
endotracheal tube. This tube size allows ventilation via a bronchoscopy adapter during use of a standard 5.9 mm outside
diameter (OD) bronchoscope. We generally prefer the 5.9 mm
OD bronchoscope because it has a working channel of 2.8 mm
which is large enough to aspirate thick secretions without
becoming clogged. Using smaller endotracheal tubes with
smaller bronchoscopes is often frustrating, due to difficulty in
clearing the secretions in order to obtain an adequate view.
The “pediatric bronchoscope,” for example, has an outside
diameter of 3.5 mm and a working channel of only 1.2 mm.
For specialized use such as laser bronchoscopy we use a 6.2 mm
OD scope which has a 3.2 mm working channel. If possible,
we place a 9.0 mm endotracheal tube in these situations.
Rigid bronchoscopy
The preoperative assessment of patients undergoing rigid
bronchoscopy also includes examination of the neck and oral
cavity. Severe cervical arthritis with a contracted, flexed neck
may make rigid bronchoscopy difficult. Poor dentition
should be noted; loose teeth are at risk during rigid bronchoscopy. Removable dental work such as bridges and dentures should be taken out prior to arrival in the operating
room. The presence of a mature tracheostomy is not a contraindication to rigid bronchoscopy. The tracheostomy
device can be removed and the patient intubated with the
rigid scope from above, or in some circumstances intubated
directly through the stoma with care taken to avoid injury to
the membranous portion of the trachea posterioly. Likewise,
rigid bronchoscopy can be performed through the tracheal
stoma in a patient following total laryngectomy.
ANESTHESIA
Awake flexible bronchoscopy
Adequate topical anesthesia is paramount to the performance
of awake flexible bronchoscopy. We begin the anesthetizing
process with the administration of a lidocaine nebulizer treatment (5 ml of 1% lidocaine solution) by a respiratory therapist. Following this, the posterior pharynx, tonsilar pillars,
and soft palate are sprayed with a 1% cetacaine spray. Next,
2–5 ml of a 2% lidocaine solution is injected transtracheally
through the cricothyroid membrane with a 21 gauge needle.
This maneuver causes the patient to cough but results in topical anesthesia of the airway. Finally, a bite block is placed in
the mouth, and the bronchoscope is introduced through the
mouth and advanced down to the level of the vocal cords.
One milliliter of a 4% lidocaine is sprayed through the working channel of the bronchoscope onto each vocal cord under
direct vision. The scope is removed, and the patient is
encouraged to cough. At this point the local anesthesia is
complete, and awake bronchoscopy can be easily performed
with satisfactory patient comfort. Intravenous sedation can
lead to hypoxemia, hypercarbia, and hypotension. With
properly administered local anesthesia the patient remains
comfortable throughout the procedure, and we rarely find it
necessary to administer any intravenous sedation.
Flexible bronchoscopy under general anesthesia
Once appropriate monitoring has been established, the
patient is preoxygenated, and general anesthesia is induced.
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General anesthesia is usually accomplished with a combination of intravenous and inhalation agents. A muscle relaxant
is administered, and direct laryngoscopy is performed. An
endotracheal tube is placed under direct vision, and its position confirmed by the presence of end-tidal carbon dioxide.
The endotracheal tube is connected to the ventilator circuit
via a bronchoscopy adapter, and the patient is ready to
undergo the procedure. Special anesthetic considerations
include minimizing the inspiratory oxygen content to below
50% when using laser bronchoscopy to avoid an airway fire as
well as increasing gas flow rates into the anesthetic circuit
when vigorous and prolonged suctioning is required.
Rigid bronchoscopy under general anesthesia
The performance of rigid bronchoscopy under general anesthesia requires close coordination between the anesthesiologist and surgeon. While the anesthesiologist institutes the
appropriate monitoring and intravenous access, the surgeon
readies the rigid bronchoscope along with its light source and
supporting hardware. During “routine” rigid bronchoscopy,
general anesthesia is induced with a combination of intravenous and inhalation anesthetics. Secretions are aspirated
from the posterior pharynx, and the patient is maskventilated. A muscle relaxant is administered to allow easier placement of the rigid bronchoscope. Patients with large
mediastinal masses or near complete obstructing tracheal
tumors represent a particularly challenging subset that
require special anesthetic consideration. Placement of these
patients in a supine position or administration of general
anesthesia with a muscle relaxant can lead to complete airway
obstruction and life-threatening hypoxemia. In this group
the airway is topicalized with local anesthesia first. The
patient remains in a somewhat upright position, and general
anesthesia is slowly induced with intravenous agents. The
anesthesiologist assists the patient’s spontaneous ventilation,
and the use of muscle relaxants is initially avoided until the
airway is secured. The patient is quickly positioned and intubated with the rigid scope by the surgeon. Ventilation
through the anesthesia circuit connected to the side port of
the ventilating scope is begun. If a nonventilating scope is
used, insufflation of oxygen via a Venturi apparatus can be
used to maintain oxygenation.
OPERATION
Awake flexible bronchoscopy
The patient is placed in a bed or stretcher and the back is elevated to 60 degrees. Pulse oximetry and heart rate monitoring
is begun. Supplemental oxygen is provided by a face mask
with a hole cut in it to allow passage of the bronchoscope.
Topical anesthesia is provided as described above in the anesthesia section. Once the oral pharynx, vocal cords, and airway
have been completely anesthetized, a bite block is placed in
the mouth, and the bronchoscope is introduced into the oral
pharynx. If the topical anesthesia has been complete, the
patient does not cough and remains comfortable throughout
the procedure.
The right-handed surgeon should stand on the patient’s
right side The surgeon’s left hand is used to introduce the
3
scope while the right hand is used on the scope control and
suction buttons. The scope is advanced to a position above
the vocal cords, and the patient is asked to take a deep breath
and vocalize. This maneuver allows direct visualization of the
vocal cords in motion. It is important to rule out a paralyzed
vocal cord in the postoperative patient who aspirates, especially if they have undergone mediastinoscopy or a left upper
lobectomy. If a vocal cord is paralyzed but fixed in the midline, no further intervention is required. Lateralization of
paralyzed vocal cord predisposes to aspiration and may
require Teflon injection to medialize the cord.
3
Operation 67
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The patient is again asked to take a deep breath opening the
vocal cords, and the bronchoscope is passed into the proximal trachea. The observer is oriented by noting the posterior
longitudinal muscle along the membranous portion of the
trachea. The carina is located, and a systematic examination
of the airway is carried out down to the subsegmental level.
Mucus plugs and thick secretions are aspirated out with the
aide of saline lavage. A sample is usually obtained for gram
stain as well as bacterial culture and antibiotic sensitivity.
Flexible bronchoscopy under general anesthesia
The patient is brought to the operating room, and general anesthesia is induced. Direct laryngoscopy is performed, and an
8.0 endotracheal tube is placed. The endotracheal tube is connected to the ventilator through a bronchoscopy adapter. The
surgeon stands at the head of the table. Flexible bronchoscopy
is carried out. Following this exam, the single lumen tube is
removed, and a double lumen endotracheal tube is placed for
isolated lung ventilation during the procedure.
We perform flexible bronchoscopy under general anesthesia on all patients undergoing a thoracic surgical procedure.
Our examination is complete and includes inspection down
to the subsegmental level on both sides. This step is especially
important in those patients undergoing a pulmonary resection associated with an endobronchial lesion. Direct visualization of the lesion allows us to plan how we will handle
division of the bronchus. If the endobronchial lesion is very
distal at the segmental or subsegmental level, we will divide
the lobar bronchus in our normal fashion with a linear stapling device. By contrast, if bronchoscopy raises the question
of a positive or “close margin” we routinely take the bronchus
open and obtain a frozen section. If the frozen section is negative, we proceed to close the bronchus with an interrupted,
hand-sewn technique. On the other hand, if the margin is
positive, we perform a sleeve resection if possible. It is unwise
to rely on an “outside” preoperative bronchoscopy when performing a pulmonary resection, and the information gained
is vital when contemplating the more complex bronchoplastic procedures.
Rigid bronchoscopy under general anesthesia
Once ready to introduce the rigid bronchoscope, the
4
patient is positioned supine with the neck slightly flexed
(“sniffing position”). The surgeon stands behind the patient’s
head, secretions are suctioned from the posterior pharynx,
and mouth guards are placed. The surgeon’s left hand is used
to control the patient’s head by gripping the maxilla with the
middle and ring fingers. The index finger and thumb of the
left hand are used to hold the scope in the manner in which
one would hold a pool stick. The right hand grasps the scope
at the level of the eyepiece.
4
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The instrument is introduced with the bevel down and
advanced until the epiglottis is visualized. The broncho-
5
scope is placed just under the leading edge of the epiglottis
which is gently elevated to reveal the vocal cords. Elevation is
provided by the operator’s left thumb. Use of the teeth or
gums as a fulcrum to elevate the epiglottis results in damage
to the teeth and must be avoided. The most common mistake
made is advancing the scope further than 1 cm beyond the tip
of the epiglottis thus placing the scope beyond the larynx.
Tongue
Epiglottis
Base of tongue
Larynx
Trachea
5a
Tip of epiglottis
Pharyngoepiglottic foldAryepiglottic fold
5b
Once the vocal cords are visualized, the scope is rotated
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6
90 degrees to the right and advanced into the trachea.
When in the trachea, the scope is rotated back to its original
position. The supporting pillow is removed from behind the
head, and the table headboard is lowered to extend the neck.
Ventilation is begun either through the side port with an eyepiece in place or via the Venturi apparatus with the nonventilating scope.
Operation 69
6
7
In order to manipulate the rigid scope, the patient’s head
7
is turned to the side opposite to that you wish to examine. To examine the right side the head is slightly turned to
the left, and the scope is passed into the right mainstem.
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We usually suspend ventilation and remove the eyepiece
8
when advancing the scope. If closer inspection of the airway is required, a Hopkins rod telescope is passed through an
adapter on the main channel of the rigid scope. These telescopes provide magnification as well as a variety of angled
views. If telescopes are not available, a flexible bronchoscope
can also be passed through the rigid scope.
8a
9
To examine the left side the head is rotated far to the
9
right. This maneuver allows for easy introduction into
the left mainstem bronchus.
8b
Further reading 71
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POSTOPERATIVE CARE
Awake flexible bronchoscopy
Following awake flexible bronchoscopy with general anesthesia, we continue to monitor the patient’s pulse oximetry for a
short period to assure the patient’s oxygenation is satisfactory. We generally obtain a chest X-ray to evaluate the results
following a therapeutic bronchoscopy, such as removing a
mucus plug in the postoperative period. Since the posterior
pharynx and vocal cords have been locally anesthetized, we
keep the patient NPO for 3–4 hours to avoid aspiration.
Flexible bronchoscopy or rigid bronchoscopy
under general anesthesia
Following these procedures, the patients are allowed to
recover from general anesthesia in a monitored recovery
room setting. Since these procedures are often done in conjunction with another thoracic surgical procedure, the more
invasive procedure, such as a pulmonary resection, dictates
the postoperative care.
Patients undergoing laser ablation of an obstructing lesion
or relief of airway obstruction by a “coring technique” utilizing the rigid bronchoscope are hospitalized and observed
overnight to ensure an adequate airway.
OUTCOME
Complication rates for these procedures should be low.
Bleeding dyscrasias should be addressed prior to the proce-
dure, especially if a biopsy is planned. A high percentage of
complications surrounding awake flexible bronchoscopy are
related to preprocedural intravenous sedation. This issue can
be avoided altogether with the proper application of local
anesthesia and avoidance or minimal use of intravenous
sedation. This principle is of particular importance in the frail
and elderly. Significant hypoxemia must be avoided during
these procedures. Some particularly tenuous patients are
probably better off undergoing elective intubation followed
by therapeutic bronchoscopy rather than struggling with
awake bronchoscopy. Avoiding hypoxemia during rigid
bronchoscopy requires teamwork and coordination between
the anesthesiologist and surgeon.
Rigid and flexible bronchoscopy are invaluable tools for
the thoracic surgeon. While flexible bronchoscopy has
become the norm, situations arise which demand the use of
rigid bronchoscopy necessitating training and confidence
with this procedure.
FURTHER READING
Fulkerson WJ. Fiberoptic bronchoscopy. New England Journal of
Medicine 1984; 311: 511–5.
Lukomsky GI, Ovchinnikow AA, Bilal A. Complications of bronchoscopy:
comparison of rigid bronchoscopy under general anesthesia and
flexible fiberoptic bronchoscopy under topical anesthesia. Chest
1981; 79: 316–21.
Miller JL. Rigid bronchoscopy. Chest Surgery Clinics of North America
1996; 6: 161–7.
Miller MB, Kvale PA. Diagnostic bronchoscopy. Chest Surgery Clinics of
North America 1992; 2: 599.
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Video-assisted thoracic surgery
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LUIZ EDUARDO V. LEÃO MD, PHD
Professor and Chairman, Department of Surgery, Division of Thoracic Surgery, Escola Paulista de Medicina – Universidade Federal de São
Paulo, São Paulo, Brazil
8
HISTORY
Thoracoscopy was used for exploration of the pleural space in
the early twentieth century by Jacobeus, but only in the late
1980s and early 1990s with development of video technology
and endoscopic instrumentation did this field expand to what
is known today as video-assisted thoracic surgery (VATS).
This approach follows the trend of less invasive techniques
that have been developed for most surgical areas.
PRINCIPLES AND JUSTIFICATION
VATS is not an operation but an approach to performing
operations. The same surgical principles should be applied as
in an open procedure, although in some cases surgical technique and strategies may be different. VATS operations also
include diagnostic and therapeutic procedures. Indication for
operation should be the same as for the open procedure.
With this less invasive approach, most operations can be
performed through two to four access ports with minimal
muscle incision and no rib spreading. Thus, less operative
pain, easier coughing, and preserved respiratory mechanics
are to be expected in the immediate postoperative period.
This less invasive procedure should result in a shorter hospitalization and, in most cases, in lower costs and earlier return
to normal and productive life.
The initial enthusiasm for and expansion of the technique
also have raised some concern regarding which procedures
can be performed by VATS and which procedures should be
performed by VATS. After more than 10 years of use, VATS
has now withstood the test of time, and several VATS techniques now have a definite role in the diagnosis and treatment
of certain thoracic conditions. Of course, the skill and judgment of the surgeon are fundamental; most importantly,
every surgeon performing VATS operations should have surgical training, and operative setup facilities should be available to allow immediate conversion to an open procedure, if
necessary.
PREOPERATIVE ASSESSMENT AND
PREPARATION
Because VATS is an approach, rather than an operation, preoperative evaluation may be very different, depending on the
underlying disease and the planned surgery. Although VATS
potentially carries less morbidity and is less invasive than thoracotomy, certain principles must be adhered to in the preoperative evaluation of the patient for thoracoscopic surgery.
Surgical indications for each situation should be the same as
those for the open procedure.
The presence of adhesions and previous pleurodesis, thoracic surgery, chest trauma, and chest tube insertions should
be carefully assessed from patient data, and computed tomographic (CT) evaluation may be included. The presence of
dense adhesions generally precludes use of a VATS procedure.
As does the patient undergoing thoracotomy, the patient
undergoing thoracoscopic surgery requires a general anesthetic. In addition, one-lung ventilation is a prerequisite for
this surgical procedure. One must also realize that any thoracoscopic procedure may have to be converted to an open thoracotomy due either to the inability to complete the planned
procedure thoracoscopically or to technical complications
such as vascular injury and hemorrhage. Thus, although thoracoscopic surgery may be planned, the patient must not
present a prohibitive risk for thoracotomy. The preoperative
evaluation of the patient undergoing thoracoscopic surgery
should be no less rigorous than that of the patient undergoing
thoracotomy.
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