Step by Step Bronchoscopy

Indications

The indications for a bronchoscopy include diagnostic as well as therapeutic with the object in each setting being different.

1. Diagnostic:

  • For Endobronchial Symptoms or Signs
    Symptoms and signs of endobronchial disease are the most common indications for a bronchoscopy.
    • Chronic cough
    • Hemoptysis
    • Atelectasis
    • Obstructive pneumonia
    • Localized wheezing
  • Lung Cancer:
    Lung cancer is one of the most common conditions where a bronchoscopy is indicated. It is necessary for:
    • Tissue diagnosis
    • Staging
    • Early diagnosis
  • Burn: Patients who sustained burns and suspected of having injuries to the respiratory passages are bronchoscoped.
  • Assessment of the endotracheal tube position

2. Therapeutic

  • Removal of Foreign Body: In general, foreign body removal is best done with a rigid bronchoscopy under general anesthesia. A fiberoptic bronchoscopy may be used as a screening procedure for suspected cases of aspiration. Patients with known or suspected foreign bodies should undergo a rigid bronchoscopy. If the evidence for aspiration is equivocal, patients should undergo a diagnostic flexible bronchoscopy, and then a rigid bronchoscopy if a foreign body is found. There have been reports of foreign body extraction using flexible bronchoscopes, but this is poorly suited for such work. I discourage its use for this purpose.
  • Lung Abscess: To rule out endobronchial lesion and for drainage
  • Tracheal Stenosis: For dilation
  • Refractory Atelectasis: with a balloon cuff
  • Respiratory Toilette: Occasionally, a bronchoscopy will be indicated for respiratory toilette. As a general rule, postural drainage, tapotage, cough and suction of secretions are sufficient. If for some reason these cannot be done, then bronchoscopy can be done for respiratory toilette. Prospective studies have shown that a good intensive respiratory toilette can accomplish good results in the control of atelectasis. While a bronchoscopy is relatively simple, it should not, in any way, replace the general principles of respiratory toilette.

3. Preliminary to Other Procedures

  • Pneumonia, Diffuse lung disease: A bronchoscopy is a preliminary to many other procedures . A bronchoscopy has to be done at times to obtain respiratory secretions for establishing the diagnosis of an infection. The choice of brushing, triple lumen microbiology brush or broncho-alveolar lavage is made appropriate to the clinical situation. After inspection of the tracheobronchial tree, depending on the clinical situation, you can: brush, biopsy, transbronchial lung or mass biopsy, BAL, triple lumen catheter, laser. A bronchoscope acts as a medium through which these accessories are introduced to the desired location to accomplish the task.
  • Difficult Intubation:
    If you experience difficulty in intubation, a fiberoptic bronchoscope can be used to help you. The endotracheal tube is passed over the bronchoscope and, under direct vision, can be introduced into the trachea.

Consent

  1. Explain the procedure to the patient and allay anxieties. Patients may have heard about the distress associated with a rigid bronchoscope. Explain that the fiberoptic bronchoscope has made the procedure much easier.
  2. Assure the patient that there is sufficient room for air to go through.
  3. Instruct the patient that he should not talk during the procedure to avoid the likelihood of injury to the vocal cord. However establish some mechanism of communication e.g. instruct to raise fist whenever uncomfortable. If a transbronchial biopsy is planned, cooperation will be required: to take a deep breath and expire slowly.
  4. Inform the patient not to expect the results immediately; normally takes two to three days before the histopathological exams are complete.

Pre-screening 

  • History of allergic reactions to local anaesthetic
  • Platelet count, coagulation profile:INR, PT and aPTT
  • Urea and creatinine
  • Evidence of recent MI/ACS
  • If there is a focal lesion present, reveiw all available imaginmake an assessment as the most probable segment
  • If there is history of asthma, consider prepare the patient with steroids or administer bronchodilator by inhaler prior to topical anaesthesia.
  • If the patient has a history of chronic obstructive pulmonary disease, ascertain baseline O2 saturation and whether patient has CO2 retention. In certain cases, respiratory depressants to premedicate may have to avoided, and thus rely primarily on local anaesthesia.
  • Medicines: Check whether patient is on aspirin, clopidogrel, Warfarin, or low molecular weight heparin

Premedication

  • Sedation: 
    • Midazolam
    • Fentanyl
    • Alfentanyl

Preparation 

  • Pre-Procedure Screening: NBM -The patient should abstain from food and liquids since midnight if the procedure is planned for the morning or after a light breakfast if planned for the afternoon. The stomach should be empty during the procedure to prevent aspiration. As a general rule, food and liquids should be withheld five to six hours prior to the bronchoscopy.
  • Assess the need for fluoroscopy: In general, all of the peripheral lesions and transbronchial lung biopsies require fluoro guidance and should be planned for.
  • Plan ahead for tests: Anticipate your needs and gather all of the necessary material ahead of time i.e. forceps, specimen bottles, TBNA needle, brush, flumazenil, ice saline, adrenaline etc.
  • Oxygenation and monitors: Start the patient on 1-2 liters of oxygen by nasal cannulation as there is an approximate drop of 10-20 mg Hg PO2 during the procedure. Providing supplemental oxygen prevents hypoxemia during the procedure and the patient's oxygenation status should be monitored by cutaneous oximetry.

Conscious Sedation

Consider starting an IV line and titrate midazolam 1mg at a time, watching the patient's response. Older patients are very sensitive. Therefore, 1 or 2 mg total may suffice. Midazolam also provides amnesia but an excessive dose can induce respiratory depression. Reversal agents Flumazenil must be available.

Monitoring

The occurrence of endoscopically induced arrhythmias and ischemic changes is well documented in both gastroscopy and colonoscopy. However, fiberoptic bronchoscopy, with the additional factor of airway intubation only has a small risk of inducing an arrhythmia. The avoidance of hypoxemia by routine use of supplemental oxygen and the use of topical lignocaine may be of importance. Close monitoring of oxygen saturations, BP and pulse, and level of consciousness in all situations where conscious sedation is done for the procedure is essential.

Administration of Oxygen

  1. Nasal cannula
  2. A mask with a hole made to permit passage of the bronchoscope
  3. Single cushioned naal prong 

Instrument

  • The bronchoscope consists of a handle and fiberoptic bundle. The light passes from the light source through the fiberoptic bundle to illuminate the bronchus. Newer scopes avail video processing technology
  • The knob of the handle controls the position of the tip of the scope: flexion and extension 
  • There is a channel for suction controlled by a button that is depressed. 
  • The channel on the side facilitates instillation of anaesthetic or saline and passage of biopsy forceps and instruments. 

Routes of Intubation

There are many ways the fiberoptic bronchoscope can be introduced. An awareness of these alternatives is important. Each method has its own unique advantage. The anesthetic procedure will vary depending on the method you have selected.
 
Transnasal: The transnasal method allows a more stable, aesthetic method, and allows the patients to swallow secretions more easily. The disadvantage is the
                   difficulty beginners seem to have in introduction of the scope and nose bleeding may occur due to injury.
 
Transoral:
    • With a mouth bite protects accidental injury to the bronchoscope and is tolerated well by the patient.
    • Transoral with soft ET tube: The soft endotracheal tube is slipped over the bronchoscope as a sleeve. The scope is then introduced directly into the trachea. The endotracheal tube is slipped into the trachea. The bronchoscope is withdrawn and a mouth bite is placed about the endotracheal tube for protection. This permits removal and re-insertion of the scope conveniently. This is especially useful in certain interventional procedures.
    • Through a rigid bronchoscope: The fiberoptic bronchoscope is introduced after insertion of a rigid bronchoscope. This method used to be practiced by thoracic surgeons in the early days. With increasing familiarity and experience with fiberoptic scope, this method of introduction of the fiberoptic bronchoscope is now rarely done.

Transtracheal:

    • Via endotracheal tube: When patients are on a ventilator, one can perform a bronchoscopy through an adapter or T-piece. The adapter permits insertion of a bronchoscope and performance of the procedure without the interruption of continuous mechanical ventilation.
    • Via tracheostomy: It is easy to introduce the bronchoscope through the tracheostomy stoma or through the tracheostomy tube via an adapter. Instill local anesthetic through the stoma and proceed with bronchoscopy.

The size of the bronchoscope and the endotracheal tube are important considerations. A size 8 tube and larger is required when using a bronchoscope 5.5 mm in diameter. With smaller tubes, the peak pressures developed by the ventilator become excessive and the risk of pneumothorax becomes higher.

For patients on the ventilator, prior to bronchoscopy increase the oxygen concentration to 100% and increase the tidal volume to account for a leak.

Bronchial Anatomy

It is essential to familiarize onerself with the segmental anatomy and get a three dimensional feel for the tracheobronchial tree.

  1. Starting in the trachea, the C-shaped tracheal rings with the posterior membranous portion normally bulging in during expiration and cough.
  2. Preferably inspect the the side opposite to the known abnormal lung. 
  3. Right bronchial tree: The right main stem bronchus is in line with the trachea and is short. The right upper lobe bronchus branches immediately beyond the carina along the lateral wall. The right intermediate bronchus continues to three orifices. Along the medial wall, is the RML, RLL straight down and the superior segment of the RLL opposite to the RML. The medial basal segment of the RLL will branch off first along the medial side. At the end you will see the posterior, anterior and lateral basal segments (three musketeers) clustered together. Withdraw the scope and a gentle turn of the bronchoscope tip towards the lateral sided will bring the RUL orifice into view with posterior, anterior and apical segments.
  4. Left bronchial tree: The left main stem bronchus is at an angulation and longer. Recognize the cardiac pulsation along the inferomedial aspect. At the orifice of the LLL, the superior segment branches off posteriorly. Upon entering the LL, the three basal segments can be seen. The left upper orifice divides into the LUL and lingular. The lingual has superior and inferior segments, the LUL has apical, posterior and anterior segments.

Endobronchial Procedures 

  • Brushing: The cytology brush can be passed through the bronchoscope to the desired site and the lesion can be brushed. The brush resides inside a protective sheath. Retract the brush into the sheath after brushing. This procedure will avoid the loss of the specimen during withdrawal of the brush.
  • Biopsy: Advance the biopsy forceps to the abnormal site. Familiarize yourself with opening and closing the forceps. Moving the handle forward opens the forceps. Under direct vision, advance the opened forceps to the selected site and close it to take a bite of the lesion.
  • Lavage: Lavage: The indications for diagnostic lavage are:
    • Sarcoidosis
    • Diffuse interstitial fibrosis
    • Opportunistic infections

Lavage returns and more frequently with the middle lobe and anterior segments. Wedge the bronchoscope into the selected segment. Slowly instill 20 cc's of saline and apply suction intermittently to collect the secretions.

  • Transbronchial Lung Biopsy:
    For peripheral lesions and diffuse lung disease, a transbronchial biopsy is indicated, and under fluoroscopic guidance where appropriate. The following lists the value of fluoroscope:
    • It is absolutely necessary for placement of the forceps into peripheral lesions that are not visible endobronchially.
    • It ensures that the forceps are open.
    • It minimizes the risk of a pneumothorax.

For diffuse lung diseases, lateral segment of the right lower lobe is preferred site.

Place the bronchoscope in the lower lobe bronchus and identify the lateral basal segment. Advance the forceps into the segment to about 3 cms near the rib cage. Open the forceps and instruct the patient to take a deep breath while simultaneously advancing the forceps. Advance the forceps until either it wedges, is close to the chest wall or the patient develops pleuritic pain. If the patient complains of pleuritic pain, withdraw the forceps slightly until there is no pain. Ask the patient to expire slowly. Close the forceps at the completion of expiration. Gently withdraw the forceps. You will note a tug on the lung. Advancement during inspiration enables the forceps to go as far as possible into the lung. The end expiration will provide you with the most lung tissue for the biopsy. Multiple biopsies (5-6) are recommended if there is no significant bleeding. Depending on the indication, the specimen should be sent for the following:

      • Histology in formalin
      • AFB and fungal cultures in saline
      • Immunofluorescent stains in saline immediately

 

  • Transbronchial Needle Aspiration: The indications for transbronchial needle aspiration are:
      • Transcarinal: For purposes of lung cancer staging or for undiagnosed mediastinal nodes.
      • For peripheral pulmonary nodules.
      • At times, even for endobronchial lesions, it is particularly useful for a submucosal process where the standard biopsy forceps may fail to provide adequate tissue.

 

  • Triple Lumen Catheter:
    The development of the plugged, double sheathed, telescoping microbiology brush catheter offers a satisfactory method of sampling lower respiratory tract secretions without contamination from the inner channel of the bronchoscope. The bronchoscope should be positioned in the orifice of the affected pneumonic segmental bronchus. Under direct vision, the sterile catheter is advanced 1-2 cm beyond the tip of the bronchoscope. The inner telescoping cannula containing the sterile brush is advanced, thereby ejection the polyethylene glyco plug. The brush is further advanced beyond the inner cannula to enable sampling of secretions. It is then withdrawn into the inner cannula, prior to removing the catheter from the bronchoscope. The distal portion is then clipped with sterile scissors into the culture medium.

 Post Procedure Management

  • Observation period:
    Post bronchoscopy management is mainly followed to screen for complications. The complications of routine bronchoscopy are negligible but is strongly recommended to observe the patient for 90-120 minutes following the bronchoscopy. If a transbronchial lung biopsy was done, the period of observation should be two hours and it is important to get a chest x-ray following a transbronchial biopsy to rule out pneumothorax.
  • Instructions to the patient
    • Not to eat or drink for another two hours. The gag reflex should return before he can resume oral consumption.
    • An attendant to drive the patient home.
    • Anticipate a sore throat and take a throat lozenge.
    • Call if a fever, shortness of breath or chest pain develops.
    • Anticipate mild haemoptysis.

Complications

  • Bacteraemia: Bacteraemia can follow any endoscopic procedure and cause fever. Most of the time, it is transitory and does not require antibiotics. This is of special concern in patients with artificial valves. There is no consensus of opinion for prophylaxis for this situation. Prospective studies have demonstrated the absence of bacteremia following a bronchoscopy. While it seems logical to provide antibiotic prophylaxis for patients with valvular disease for bronchoscopy, it is not supported by scientific evidence.
  • Pneumonia: Fortunately, post bronchoscope pneumonia is rare. Transitory infiltrates with fever have been observed in one study in 6% of patients following a bronchoscopy. Rarely has fatal pneumonia been reported following a bronchoscopy. Pseudomonas pneumonia has been traced to contaminated bronchoscopes. The procedure is not sterile but pneumonia is rare following the procedure. 
  • Tuberculosis: The spread of tuberculosis to patients by a contaminated bronchoscope though rare, has been reported. 
  • Hypoxemia: The arterial PO2 drops by 10-20 mm of mercury routinely during a bronchoscopy. The worst drop occurs during saline lavage. This complication can be prevented with routine use of supplemental oxygen therapy. 
  • Pneumothorax: A pneumothorax can occur if a transbronchial lung biopsy or brushing of the lung was done during the bronchoscopy. This is uncommon with bronchoscopy alone except in ventilated patients. With an endotracheal tube, the airway resistance increases during bronchoscopy and the resulting barotrauma can lead to a pneumothorax. To minimize this complication, use either larger ET tubes or smaller bronchoscopes, minimize the duration of the procedure and inspect the bronchial tree intermittently.
  • Respiratory Failure:
  • Anesthetic Reaction:
  • Haemoptysis: Bleeding and haemoptysis can occur following a biopsy or brushing. Excessive suction can also injure mucous membranes and cause bleeding. Use of 1 in 1000 adrenaline solution prior to the biopsy is recommended to minimize the amount of bleeding. Patients with a coagulation defect should not be biopsied.
  • Arrhythmia: Arrhythmias and ischemia are minimal.
  • Aspiration from Lung Abscess

Contraindications 

  • Uncooperative Patient: Uncooperative or mentally deranged patients are not suitable candidates for fiberoptic bronchoscopy under local anesthesia. A bronchoscopy must be performed under general anesthesia. This is not a contraindication for a bronchoscopy. However, it is an issue regarding the type of anesthesia used.
  • Acute Myocardial Infarction: Recent myocardial infarction, unstable angina and serious dysarrhythmias are relative contraindications for a bronchoscopy.
  • C02 retention
  • Low PO2
  • Coagulation defect: There is no contraindication for a bronchoscopy in patients with uremia or patients with a known coagulation defect. Of course, there is a contraindication for brushing or biopsy. Bronchoalveolar lavage can be done safely in these patients.
  • Tracheal stenosis: You should be aware of the concept of "open" and "closed" bronchoscopy. Fiberoptic bronchoscope is a closed bronchoscope, while the rigid bronchoscope is an open scope. In patients with tracheal stenosis, be aware that if you the scope is advanced to beyond the stenosis one could be completely occluding the airway.
  • Foreign body: If you are sure of the prescience of a foreign body, it is best to do a rigid bronchoscopy under general anaesthesia. Fibreoptic bronchoscopy can be used as a screening procedure.
  • Asthma: Asthmatics can develop severe laryngospasm and bronchospasm during a bronchoscope. With proper preparation, using steroids and bronchodilators, the procedure can be carried out safely. I routinely give 200 mg of hydrocortisone the night before and immediately prior to the procedure. The preprocedural administration of bronchodilating agents is an important step in the prevention of complications. 
  • SVC syndrome: Superior vena caval syndrome used to be considered a contraindication for a bronchoscopy, the main concerns being bleeding.