Rigid bronchoscopy

INTRODUCTION — 

Rigid bronchoscopy is a technique that visualizes the trachea and proximal bronchi. It is usually performed in the operating room under general anesthesia. Better suction and airway control compared with flexible bronchoscopy make rigid bronchoscopy a first-choice procedure in the management of complex airway obstruction.

The uses, equipment, procedural technique, and complications of rigid bronchoscopy are reviewed here. Flexible bronchoscopy is discussed separately. (See "Flexible bronchoscopy in adults: Overview".)

CLINICAL USES — 

Clinical uses of rigid bronchoscopy include securing, diagnosing, and treating central airway obstruction (CAO; trachea or proximal bronchi (figure 1)) [1-3]. It is typically used when flexible bronchoscopy fails. The most common conditions when bronchoscopy is used for CAO are the following:

●Benign or malignant tumor obstruction – (See "Clinical presentation, diagnostic evaluation, and management of malignant central airway obstruction in adults", section on 'Bronchoscopy' and "Presentation and diagnostic evaluation of non-life-threatening and nonmalignant subglottic and tracheal stenosis in adults", section on 'Bronchoscopic evaluation'.)

●Foreign body inhalation – (See "Airway foreign bodies in adults", section on 'Rigid bronchoscopy'.)

●Life-threatening hemoptysis – (See "Evaluation and management of life-threatening hemoptysis", section on 'Initial bronchoscopy'.)

Compared with flexible bronchoscopy, the rigid bronchoscope has many benefits including the following:

●Maintenance of the airway and ventilation during the procedure.

●A large working channel that allows multiple instruments to be used simultaneously.

●The availability of larger suction equipment and forceps for easy retrieval of debris, thrombus, and foreign bodies (table 1).

However, the rigid bronchoscope cannot be used to access the airway beyond the proximal bronchi (figure 1). Thus, it is common to introduce a flexible bronchoscope through the rigid bronchoscope for the purpose of examining airways beyond the proximal bronchi.

There are few contraindications to rigid bronchoscopy, which mostly center around the provision of general anesthesia, especially in those with underlying chronic lung disease. Other contraindications are similar to those undergoing flexible bronchoscopy (eg, hemodynamic instability, coagulopathy). (See "Flexible bronchoscopy in adults: Preparation, procedural technique, and complications", section on 'Complications'.)

EQUIPMENT — 

Local expertise and institutional resources often determine the type of equipment used during rigid bronchoscopy [4]. Basic components include the rigid bronchoscope, visualizing equipment, and accessory instruments.

Rigid bronchoscope (hollow metal tube) — The rigid bronchoscope is a hollow stainless steel tube (picture 1 and figure 2 and figure 3) of variable size through which a rigid telescope is placed. It is also termed an open-tube, straight, or ventilating bronchoscope.

●Size – The external diameter of a rigid bronchoscope ranges from 2 to 14 mm, wall thickness from 2 to 3 mm, and length from very short (for pediatric cases or working in the trachea; eg, 15, to 30 cm) to long or extra-long (for adults or working in the bronchi; eg, up to 40 cm). Tubes with an extra-large diameter have been developed for exceptional cases of tracheobronchomalacia, but they are not readily available.

Some bronchoscopists use only a single manufacturer's rigid bronchoscope, which comes in one or two varying sizes. Other bronchoscopists prefer a set of rigid bronchoscopes with multiple lengths and diameters.

●Shape – Rigid bronchoscopes are the same diameter from the proximal to the distal end, except for the beveled end or tapered tip, which lifts the epiglottis during intubation or facilitates the dilation of airway strictures by "coring" through the obstruction. (See 'Procedures' below.)

●Accessory ports – Most rigid bronchoscopes are round when visualized in cross-section while some are oval.

The proximal end has a central opening; it may also have external side ports that permit the simultaneous introduction of suction catheters, bronchoscopic tools (eg, laser equipment), and ventilation (picture 2). These tools can also be passed through the proximal central opening.

Other rigid bronchoscopes have fenestrations in the shaft to allow contralateral lung ventilation when accessing the central bronchi (picture 1).

Rubber or silicone caps may be used on proximal ports to minimize air leaks during ventilation. They may also have pinpoint piercings for the insertion of accessory instruments. (See 'Accessory instruments' below.)

Some rigid bronchoscopes have a small internal channel through which the rigid telescope passes while others are simply empty tubes that allow passage of a separate rigid telescope.

Some rigid bronchoscopes can analyze exhaled gases.

Visualizing equipment (telescope, light, video) — The following is needed to visualize the airways:

●Rigid telescope – Rigid telescopes are inserted through the rigid bronchoscope to visualize the airways at angles of 0, 30, 40, 50, 90, 135, and 180 degrees (with respect to the axis of the telescope). This facilitates visualization of the trachea, mainstem bronchi, and origins of the upper and lower lobes airways bilaterally (figure 4 and figure 5).

●Light source – The light source is also inserted directly through the rigid bronchoscope (typically xenon and halogen lamps). Newer light sources have devices that regulate the amount of applied light (ie, automatic light intensity regulators, automatic irises) to minimize glare.

A few systems allow direct visualization through the rigid bronchoscope using light conducted through a tube that extends the length of the rigid bronchoscope or through a prism at the proximal end.

●Video equipment – Video is ideal for teaching, documenting procedures, and allowing multiple viewers. Single- or three-chip video cameras can be easily connected to the proximal aspect or eyepiece of a rigid telescope via direct connection devices, snap-on lenses, or standard C-mounts.

Alternatively, a flexible bronchoscope with its own light source and video can be inserted through the rigid bronchoscope. (See "Flexible bronchoscopy in adults: Overview".)

Accessory instruments — Accessory instruments that may be used during rigid bronchoscopy include forceps (figure 6) for biopsy or foreign-body removal, suction tubing, and instruments used to insert and remove airway prostheses (eg, stents and other equipment for specific procedures). These instruments are generally inserted through the rigid bronchoscope (either via a silicone cap or open port). Occasionally, instruments such as forceps may be passed along the outside of the rigid bronchoscope when, for example, a different angle may be needed to access an airway. A flexible bronchoscope may also be inserted for better visualization of the lower airways.

PREPARATION — 

An example of a checklist we use is provided in the table (table 2).

Patients and equipment — Rigid bronchoscopy is typically performed under general anesthesia in an operating room. However, limited data suggest it can be performed at the bedside in an intensive care unit setting [5]. It should only be performed by clinicians with expertise.

●For elective procedures, the patient should fast for eight hours and clear liquids are allowed within two hours before the procedure [6].

●Since rigid bronchoscopy is a form of intubation, we suggest using a preprocedure assessment similar to those used for endotracheal tube (ETT) insertion. In brief, this includes the following:

•A time-out

•An evaluation of body habitus and potential for difficult or impossible rigid intubation

•Conversations with the anesthesiologist to ensure a secure airway in case of complications before, during, or after rigid intubation

•An oral and airway preassessment to ensure an adequate seal can be maintained during mask ventilation

•An assessment of cervical spine stability since neck hyperextension is important for rigid bronchoscope insertion

•Suction and monitoring equipment

•Intravenous access

•Medications

•A selection of rigid bronchoscopes (having both tracheal and bronchial tubes available and ready)

•A plan for equipment to be used during the rigid bronchoscopic procedure

Details of preparation for ETT insertion are provided separately. (See "Direct laryngoscopy and endotracheal intubation in adults", section on 'Preparation'.)

●The patient is also preoxygenated and positioned similarly to patients undergoing intubation with an ETT. (See "Direct laryngoscopy and endotracheal intubation in adults", section on 'Positioning the patient'.)

Anesthesia/ventilation — Our approach is the following:

●Anesthesia – All patients are assessed by anesthesiologists for general anesthesia risk. General anesthesia with intravenous anesthetic agents is typically used (eg, intravenous fentanyl and propofol) [7,8]. This avoids the use of paralysis and may shorten the procedure duration. However, in some cases, inhaled anesthetic gases and paralytics are used (eg, for jet ventilation). (See "Overview of anesthesia".)

●Ventilation – Ventilatory support is provided using assist-controlled volume-controlled mechanical ventilation [1,3] or jet ventilation [9,10]. Controlled ventilation is needed when paralysis is used. The choice is often anesthesiologist-dependent. (See "Modes of mechanical ventilation".)

During volume-controlled ventilation, we typically pack the nostrils with Vaseline gauze and use wet rolled gauze to pack the mouth (picture 3). Packing avoids anesthesia gas leakage and secures the rigid bronchoscope. In addition, ventilatory tubing is typically attached to a standard fitting on the proximal port on the rigid bronchoscope.

PROCEDURAL TECHNIQUE

Intubation — Several techniques can be used for intubation:

●Direct intubation using a rigid bronchoscope and telescope – Direct intubation using a rigid telescope is the method of choice for rigid bronchoscope intubation. Rigid bronchoscope intubation can be performed with or without a rigid telescope that sits inside the rigid bronchoscope. We typically use both the rigid bronchoscope and telescope. The oropharyngeal and laryngeal structures are viewed directly through the telescope using illumination with or without video in a method that is similar to laryngoscopic intubation (see "Direct laryngoscopy and endotracheal intubation in adults" and "Direct laryngoscopy and endotracheal intubation in adults", section on 'Laryngoscopy Technique'). If a rigid telescope is not used (which is uncommon), the bronchoscope is introduced using only the naked eye.

When a rigid bronchoscope and telescope are used, our approach is the following:

•The rigid telescope is placed inside the rigid bronchoscope to allow full visualization of the beveled tip; the telescope does not fit tightly inside the rigid tube but should be free enough to slide up and down with enough space left for accessory instruments. (See 'Accessory instruments' above.)

•The bronchoscopist stands directly behind the head of the supine patient. Positioning is discussed separately. (See 'Patients and equipment' above.)

•The dominant hand holds the rigid bronchoscope with the beveled tip facing anteriorly. The middle finger of the nondominant hand is used to protect the upper teeth and gums and to control head movements. The telescope should not extend beyond the edge of the rigid bronchoscope to prevent inadvertent injury to the oropharynx and larynx (picture 4).

•The bronchoscope is inserted into the mouth, and the uvula is identified posteriorly. The bronchoscope is advanced along the route of the tongue.

•The rigid bronchoscope is gently lifted upwards, and the epiglottis is brought into view (movie 1 and picture 4). The anterior aspect of the beveled tip of the bronchoscope is then slid under the epiglottis similar to laryngoscopy with a Miller blade. Gentle advancement of the rigid tube provides further access to the larynx.

•After both arytenoids are identified, the rigid tube is lifted more anteriorly and the vocal cords are seen (figure 7). As the vocal cords are approached, the tip of the bronchoscope is rotated 90 degrees laterally (three o'clock position) (figure 8).

•The bronchoscope is advanced and rotated to enter the trachea without traumatizing the larynx.

•Once beyond the level of the cricoid cartilage, the bronchoscope may be rotated another 90 degrees to the six o'clock position so that the beveled tip lies along the posterior wall of the trachea (movie 2).

•Ventilation is initiated.

●Laryngoscopic intubation – For operators who are more adept at laryngoscopy than direct methods, the vocal cords may be visualized using a laryngoscope using a straight or curved blade (see "Direct laryngoscopy and endotracheal intubation in adults", section on 'Laryngoscopy Technique'):

•The laryngoscope is inserted as usual. (See "Direct laryngoscopy and endotracheal intubation in adults", section on 'Opening the mouth and inserting the blade'.)

•The rigid bronchoscope is then passed through the mouth and vocal cords similar to how an endotracheal tube (ETT) is introduced into the trachea. (See "Direct laryngoscopy and endotracheal intubation in adults", section on 'Curved blade laryngoscopy'.)

•As the bronchoscope is inserted between the vocal cords, it is rotated slightly and kept in the midline to avoid striking the beveled edge of the bronchoscope against the lateral wall of the subglottis (movie 2).

•Once the bronchoscope is in the trachea, the laryngoscope is removed.

•The rigid telescope can be placed into the rigid bronchoscope and the bronchoscope advanced further into the tracheal lumen. Once at the level of the cricoid cartilage, the beveled tip is rotated to the six o'clock position and ventilation is initiated.

Techniques are modified for those with an ETT or tracheostomy in place:

●Preexisting ETT – For patients with an ETT in place, the rigid bronchoscope is placed alongside the ETT until the vocal cords are reached (picture 4). Secretions are suctioned as the ETT cuff is deflated, the ETT is removed, and the rigid bronchoscope is advanced into the trachea.

●Preexisting tracheotomy – Intubation through a tracheotomy is performed via the open stoma (eg, laryngectomy patients). The bronchoscopist stands behind the patient and slightly to the patient's left or right. After topical anesthesia with viscous lidocaine is applied to the edges of the tracheotomy skin, the rigid bronchoscope can be inserted directly through the stoma from a lateral or superior position. Care is taken to avoid striking the beveled edge of the rigid bronchoscope against the posterior tracheal wall.

Procedures — Several procedures can be performed through the rigid bronchoscope under rigid or flexible telescopic guidance.

●Tumor coring and debridement – The beveled edge of the rigid bronchoscope can be used to mechanically remove tumor fragments from the airway wall ("tumor coring"). Debris is removed by suctioning, cryoprobe, or forceps. Bleeding can be controlled using pressure exerted by the wall of the bronchoscope itself or other modalities, such as argon plasma coagulation.

This method may be useful for debulking tumors and lowering the fraction of inspired oxygen so that thermal and other ablative techniques, such as the below, can subsequently be used safely:

•(See "Endobronchial electrocautery", section on 'Endoscope'.)

•(See "Bronchoscopic laser in the management of airway disease in adults", section on 'Procedure'.)

•(See "Bronchoscopic argon plasma coagulation in the management of airway disease in adults", section on 'Procedure'.)

•(See "Bronchoscopic cryotechniques in adults".)

•(See "Endobronchial brachytherapy", section on 'Technique'.)

•(See "Endobronchial photodynamic therapy in the management of airway disease in adults", section on 'Procedure'.)

Choosing among these options is discussed separately. (See "Clinical presentation, diagnostic evaluation, and management of malignant central airway obstruction in adults", section on 'Choosing among modalities'.)

●Foreign body retrieval – Large forceps, snares, baskets, and cryotherapy may be used to retrieve foreign bodies, particularly those that cannot be retrieved by flexible bronchoscopy. (See "Airway foreign bodies in adults", section on 'Rigid bronchoscopy'.)

●Stenotic dilation – The barrel of the rigid bronchoscope can be used to dilate stenoses, including subglottic stenoses. Alternatively, balloons or bougies can be combined with the rigid bronchoscope. The main advantage of using a rigid bronchoscope is the ability to maintain a safe airway with continued ventilation, which is not feasible with a balloon or bougie dilation via a flexible bronchoscope. (See "Flexible bronchoscopy balloon dilation for nonmalignant airway strictures (bronchoplasty)", section on 'Procedure'.)

●Airway stenting – The rigid bronchoscope is the preferred method for inserting silicone stents (picture 5) [3]. (See "Airway stents", section on 'Insertion technique'.)

●Management of massive hemoptysis – Many operators prefer rigid bronchoscopy in patients with life-threatening hemoptysis since it can directly tamponade the bleeding and provide better suctioning of large clots and a better view of the bleeding site compared with flexible bronchoscopy. (See "Evaluation and management of life-threatening hemoptysis", section on 'Initial bronchoscopy'.)

COMPLICATIONS — 

Although variable, complication rates are low (approximately 3.4 percent) [11-16]. Most are mild (eg, sore throat and neck pain), and major complications are rare (mortality rate <0.5 percent).

●Most complications of rigid bronchoscopy are related to standard complications of general anesthesia.(See "Overview of anesthesia".)

●Complications specific to rigid bronchoscopy are often due to poor insertion technique (eg, prolonged larynx and vocal cords trauma), gas exchange abnormalities, or hemodynamic instability.

•Complications similar to those described for endotracheal intubation can also be seen (see "Direct laryngoscopy and endotracheal intubation in adults", section on 'Complications'). Airway laceration and perforation may be a greater risk than endotracheal intubation due to the size and inflexible nature of the rigid bronchoscope, especially during emergency procedures. For example, vocal cord luxation, perforation of the posterior wall of the trachea, perforation of the wall between the trachea and the esophagus, and laceration of the larynx or tracheal wall with bleeding are more commonly seen with rigid bronchoscopic intubation than endotracheal intubation. However, these complications are rare.

•In addition, management of some complications may be different. For example, laryngospasm can sometimes be treated by prying the vocal cords open with the beveled edge of the rigid tube. As another example, in patients with apnea, the rigid tube can be rapidly inserted into the airway for manual ventilation. These and other airway complications are discussed separately. (See "Complications of airway management in adults".)

●Complications can also be due to bronchoscopic procedures, which are discussed separately:

•(See "Flexible bronchoscopy in adults: Preparation, procedural technique, and complications", section on 'Complications'.)

•(See "Flexible bronchoscopy balloon dilation for nonmalignant airway strictures (bronchoplasty)", section on 'Complications'.)

•(See "Bronchoscopic laser in the management of airway disease in adults", section on 'Complications'.)

•(See "Bronchoscopic argon plasma coagulation in the management of airway disease in adults", section on 'Complications'.)

•(See "Endobronchial electrocautery", section on 'Complications'.)

•(See "Airway stents", section on 'Bronchoscopy-related'.)

•(See "Endobronchial brachytherapy", section on 'Complications'.)

•(See "Bronchoscopic cryotechniques in adults", section on 'Complications'.)

EDUCATION AND TRAINING — 

Expertise in rigid bronchoscopy requires supervised training. However, data suggest that rigid bronchoscopy skills are variable [17] and no guidelines regulate training.

SUMMARY AND RECOMMENDATIONS

●Uses – Rigid bronchoscopy is a central airway-accessing technique that visualizes the trachea and proximal bronchi (figure 1). It is most commonly used to secure the airway, diagnose and treat complex central airway obstruction, retrieve foreign bodies, and manage life-threatening hemoptysis. Contraindications include those of general anesthesia and flexible bronchoscopy (eg, hemodynamic instability, coagulopathy). Differences between flexible and rigid bronchoscopy are listed in the table (table 1). (See 'Clinical uses' above and "Flexible bronchoscopy in adults: Preparation, procedural technique, and complications", section on 'Complications'.)

●Equipment – The rigid bronchoscope consists of a hollow stainless-steel tube through which a rigid telescope can be placed. The distal end of the rigid bronchoscope is usually beveled to facilitate intubation and lifting of the epiglottis while the proximal portion is equipped to accommodate attachments, provide side port ventilation, and permit insertion of ancillary instruments (picture 2 and picture 1 and picture 6). (See 'Equipment' above.)

●Technique – Our approach is the following:

•Preparation – Rigid bronchoscopy is usually performed under general anesthesia (typically intravenous anesthesia with assisted spontaneous ventilatory support) in an operating room by clinicians with specialized training. Patients should be assessed preoperatively by an anesthesiologist, using a process similar to that of patients undergoing laryngoscopic intubation with an endotracheal tube (ETT). (See 'Preparation' above and "Direct laryngoscopy and endotracheal intubation in adults", section on 'Preparation'.)

•Intubation – Direct intubation using a rigid telescope is the method of choice for rigid bronchoscopic intubation. With this technique, the rigid telescope is placed inside the bronchoscope and the laryngeal structures are viewed directly through the telescope (movie 1 and movie 2). Similar principles are used for intubation using laryngoscopy, with an ETT in place, or via a tracheotomy stoma. (See 'Intubation' above.)

•Interventional procedures – The rigid bronchoscope can perform several procedures, including tumor coring and debridement, foreign body retrieval, stenotic dilation, airway stenting, and airway hemostasis. (See 'Procedures' above.)

●Complications – Complications are uncommon (<4 percent) and mostly mild. Most complications relate to intubation, anesthesia, and ancillary procedures. Rigid bronchoscopy carries a higher risk of laceration and perforation than endotracheal intubation with a flexible endotracheal tube. flexible bronchoscopy. (See 'Complications' above.)