Interventional Bronchoscopy

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ALTHOUGH MANY OF OUR ENDONURSE READERS commonly perform gastroenterology-related procedures, many of them also participate in endoscopic procedures that involve structures outside the GI tract. One of the primary specialties is bronchoscopy, which is performed on both an inpatient and outpatient basis. Bronchoscopy technology has grown in leaps and bounds; for example, new narrow-band imaging offers improved optics, slimmer scopes, and greater ease of handling. This type of imaging filters specific wavelengths of light to allow better visualization of different elements of the body’s infrastructure, such as blood vessels, mucosal surfaces, and malignancies. In this special section, three nurses with long experience in endoscopy offer their thoughts on the dramatic improvements that have transformed this field.

Airway obstruction can occur with both benign and malignant processes and can produce recurrent pneumonia, respiratory insufficiency, and death. Symptoms can develop over time or suddenly. Since all patients are not surgical resection candidates, treatment is usually palliative. Technical developments in the past 20 years have generated multiple types of interventional bronchoscopic treatments. Options for interventions depend on the equipment and trained personnel available at the center performing the procedures. Several techniques available include laser therapy, electrocautery, argon plasma coagulation (APC), photodynamic therapy (PDT), cryotherapy, airway stenting, and balloon dilatation.

Bronchoscopy technology has come a long way. Not only can medical staff see the lungs in "normal" light, they can also now see with narrow band imaging (NBI), a new endoscopic imaging modality that improves visualization of subepithelial vascular patterns of the bronchial mucosa. In the photos above, a pathology is seen with a regular bronchoscopy image (top) and an NBI image (bottom). Photos provided via Olympus America, courtesy of Felix Herth, MD, Thoraxklinik, Heidelberg, Germany.

Most of these therapeutic procedures have common complications, nursing considerations and patient education associated with them, but some are specific to the intervention being performed. Fiber-optic bronchoscopy is the preferred technique for these types of interventional procedures. Rigid bronchoscopy is also an option, but if used, should be under general anesthesia. All interventional fiber-optic bronchoscopy procedures can be done either under general anesthesia or conscious sedation.

A description of the interventional therapy, its indications, and the specific procedure, any complications associated with the therapy, nursing considerations, and patient education specific to the therapy will be discussed.

Laser Therapy

Laser therapy is performed with the Nd:YAG laser. It is the most frequently used laser in bronchoscopy. The thermal tissue damage and destruction of obstructing lesions is caused by the tissue-light interaction. This procedure produces rapid tissue destruction in a single setting causing deep tissue vasoconstriction with a penetration depth of up to 10 mm.

Indications include short endobronchial central airways lesions, either benign or malignant with a visible distal lumen, and hemoptysis. It is also useful in cases of benign airway stenosis, webs caused by inhalation injury, post-intubation injury, foreign body inhalation, lung transplantation, and granulation tissue caused by resections and reanastomosis.

The procedure involves connecting the optic fiber to the Nd: YAG laser. Energy is delivered through the flexible fiber inserted through the bronchoscope. The emission is invisible, so a helium-neon aiming beam is used in conjunction to visualize the focal target area. Laser pulses of one second or less are usually used, and the power setting is not usually higher than 40 watts. Effects on lumen size are usually immediate and accompanied by excellent control of bleeding, but are not long lasting.

Complications that can occur are combustion of the endotracheal tube or fiber-optic bronchoscope, hypoxemia, and respiratory failure. Although very rare, an arterial air embolism may produce myocardial ischemia (MI) or cerebral vascular accident (CVA).

Nursing considerations for laser therapy to avoid accidental injury from laser scatter include: keeping patients’ eyes covered with saline-soaked pads, and requiring personnel to wear protective goggles. To prevent combustion: prior to firing, silicone stents should be removed; during laser firing, inspired oxygen should be kept below 40 percent; the laser should be placed on stand-by mode when the fiber is either inserted or removed through the scope; and the laser fiber should be kept a significant distance beyond the tip of the bronchoscope. Also, you may need large amounts of saline lavage for the procedure to clear debris.

Electrocautery

Electrocautery involves a high frequency current and, when it is applied directly to human tissue, heat is produced and tissue necrosis occurs. This intervention can be used for coagulation or resection effect, depending on the voltage used.

Indications include malignant and benign lesions, debulking of tumors and removal of granulation tissue, hemoptysis, immediate hemostatic control, and coagulation.

Adequate visualization of the lesion is essential for this procedure. An electrode (either monopolar or bipolar), a bronchoscope, and a generator are needed for the procedure. The electrode is connected to the generator and passed through the bronchoscope. When the current is applied directly to the tissue via the electrode, heat develops, and this produces a rapid thermal destruction of the tissue.

Complications can include perforation, pneumothorax, tracheal fires, ignition of endotracheal tubes and bronchoscopes or silicone endoprostheses, bleeding, aspiration pneumonia, electrical shock or burns to the patient or operator, and ventricular fibrillation if used close to the heart. Cartilaginous rings can be destroyed, leading to unstable structural support.

Nursing considerations specific to electrocautery with unipolar electrodes include using with caution in patients with cardiac pacemakers or implanted defibrillators since this intervention can deprogram the devices. Patients should not have any contact with the metal from the table, and sheets should be dry. Flammable anesthetic agents should not be used due to risk of ignition, and inspired oxygen should be kept at its lowest level to maintain adequate oxygenation and reduce the risk tracheal fires.

Argon Plasma Coagulation (APC)

A non-contact form of electrocoagulation is called APC. This therapy allows for a rapid coagulation of tissue with minimal manipulation to a large area quickly. Argon gas is emitted through a Teflon tube passed through the bronchoscope. The gas is exposed to the high frequency current and is ionized, and an electrical arc is formed, which causes tissue destruction without direct contact.

Indications for this intervention include hemoptysis, neoplastic airway obstruction due to lung cancer and metastatic malignancies, superficial bleeding, and debulking of granulation tissue and papillomas.

The APC procedure is composed of an argon gas source, a computer, an electrosurgical generator, and an endoscopic probe. APC utilizes electronically conductive argon plasma as a medium to deliver a high-frequency current via a flexible probe placed through the bronchoscope.

The visible surface of the mass is sprayed with the argon beam, decreasing the risk of bleeding and causing a degree of tumor shrinkage. Even though there is no direct contact of the probe to the tissue, the penetration depth is generally 2-3 mm. This tissue then becomes crusted or coagulated and is removed by a grasping forcep or suction. Patients with incomplete debulking and evidence of mucus plugging may require a second bronchoscopy to remove the devitalized tissue after 48 to 72 hours.

Complications are rare, but a systemic air embolism may occur.

Nursing considerations for this procedure when using the argon gas are to keep the inspired oxygen less than or equal to 40 percent.

Photodynamic Therapy (PDT)

This is a non-surgical oncologic treatment in which there is a drug-light interaction to internal surface tumors. The most common agent used is Photofrin® (porfimer). The standard dose is 2 mg/kg injected slowly over five to 10 minutes. The drug is usually cleared from most organ systems within 72 hours, although it can be retained longer in the tumor, the liver, spleen, and skin up to 30 days. Argon-pumped or KTP (potassiumtitanyl- phosphate) lasers that emit a non-thermal laser light are the most commonly used light sources.

Indications for PDT therapy as approved by the Food and Drug Administration (FDA) are for the treatment of microinvasive endobronchial non-small cell lung cancers in patients for whom surgery or radiotherapy are not indicated. It is also indicated for malignant airway obstruction not responsive to laser therapy.

The procedure involves a patient being injected with the medication, and after a set interval (usually 48 hours), the procedure is performed. A fiber is connected to the laser machine, and placed past the tip of the bronchoscope close to the lesion. The tumor is exposed to light energy via the fiber which triggers a cytotoxic reaction. Since the laser light is non-thermal, the effects of PDT are not seen immediately. Recommendations are to initially apply 200 joules of energy per cm and bring the patient back in two days for a repeat bronchoscopy to apply more energy if needed and remove any debris.

The most common complication from PDT is photosensitivity of the skin. Other uncommon complications may include a cough, blood streaked sputum, and chest discomfort (usually related to an inflammatory response). There may also be edema and increased secretions that can lead to airway compromise within 24 to 48 hours post-treatment.

Patient education needs to start before the patient is injected with the medication. Since patients are photosensitive, and at risk for a sunburn immediately following the injection and up to four to six weeks, it is important to teach them photosensitivity precautions. Patients are instructed to bring protective clothing and eyewear to their injection appointment. When they leave after the injection, they must be covered from head to toe with no skin exposed whenever they are exposed to bright sunlight. This includes riding in a vehicle, at home in front of the windows and any time the patient is exposed to bright lights.

Cryotherapy

Cryotherapy is a technique in which tissue is destroyed as a result of freezing. The damage induced by freezing occurs at the molecular, cellular, and tissue levels. The aim of cryotherapy is to create the fastest possible cooling of the target tissue in order to provoke intracellular freezing. The cooling agents used are liquid nitrogen, nitrous oxide and carbon dioxide.

Indications for this technique are useful in a variety of clinical settings, particularly in the ablation or palliation of accessible malignancies such as bronchogenic carcinomas. Polypoid lesions are most suitable for cryotherapy.

There are three parts to the cryo machine: the console, the cryoprobe, and the transfer line that connects the console and gas cylinder to the probe. During bronchoscopy, the cryoprobe is placed through the biopsy channel, and the tumor site is located. The probe is placed on the tumor or pushed into it in order to produce circumferential freezing of maximal volume. Three freeze-thaw cycles are carried out at each site. The probe is then moved 5-6 mm and another three cycles are carried out in the adjoining area. The points of impact are staggered out with an overlap of the frozen zone with respect to the previous site. The procedure is continued until the entire visible part of the tumor has been frozen. A repeat bronchoscopy is performed eight to 10 days after the first session, to access for cyrodestuction, removal of any slough and to repeat cryotherapy if required.

A complication of post-procedure edema can occur. Corticosteroids may be given 24 hours post-treatment for some tracheal or subglottic lesions in which the risk of airway compromise is of more concern Nursing considerations specific for cryotherapy include discontinuing anti-coagulants prior to bronchoscopy.

Airway Stents

Airway stents (also known as tracheobronchial prostheses) are hollow devices used to treat a variety of large airway diseases. The types of stents available are silicone, metal and hybrid. Bronchoscopy is the preferred technique for these types of stent placement.

Indications include palliative treatment of dyspnea, intractable cough, or respiratory insufficiency due to airway obstruction. Other indications for their use may include malignant obstruction with extrinsic airway compression, post-intubation subglottic stenosis after laser resection or dilation, benign tracheal stenosis in non surgical candidate patients, benign tracheal or bronchial stenosis from an inflammatory or infectious process, localized or extensive tracheobronchomalacia, anastomotic stricture or dehiscence following lung and heart-lung transplantation, and tracheal or bronchial-esophageal fistula.

The procedure depends on the type of stent to be deployed and the preference of the operator, whether a rigid or flexible bronchoscope is required. Once the area of stenosis is determined the distance from the vocal cords and the length and diameter of the lesion is documented during bronchoscopy, the stent can then be placed. Dilation, cryosurgery, electrocautery, or Nd: YAG laser resection may be used to open up or clear the airway for optimal placement. Placement of sequential stents of increasing size can be used when the rigidity of a lesion makes dilation unsafe or impractical. Silicone stents are best used for this, because they are easily removed and replaced. Alternatively, a self expanding metal stent can be inserted and may restore airway patency. In these cases, proper selection of stent caliber and length is essential.

Although the tracheobronchial tree usually does not react well to the introduction of foreign bodies, most stents are welltolerated. Bronchoscopy should be performed in patients who have symptoms of cough, and dyspnea post-placement, to document patency and proper stent positioning which may be a complication of the procedure. Another complication may be stent obstruction by accumulated secretions, or recurrent tumor growth. Stent migration can be caused by a violent, persistent cough, tumor growth, or resolution of the extrinsic compression which maintained the stent in place. Airway wall perforation or stent rupture may occur from self expanding metal stents.

Balloon Dilation

Bronchoscopic balloon dilation is a simple, non-traumatic, rapid method to dilate a stenosis and restore adequate air flow. It may be used in combination with other techniques such as surgery, laser resection, cryotherapy or electrocautery.

Indications include treatment of tracheobronchial stenosis.

The procedure involves using a bronchoscope with a diameter of 2mm or 2.2 mm. The airways are inspected and the area of stenosis is identified. A guidewire is inserted through the working channel of the bronchoscope and advanced beyond the stenosis. This procedure is to be done using fluoroscopy to avoid coiling, sharp bends, or extending the wire into the lung periphery. The balloon is passed over the guidewire and should protrude enough beyond the end of the stenosis so that dilation of the entire lesion will occur when the balloon is inflated. The balloon is inflated with water to pressure between 45 psi and 131 psi, based on the balloon used. The balloon is kept inflated for least one to two minutes, depending upon the patient’s tolerance. Repeated inflations with the same balloon may be done to achieve the desired affect. After dilation is complete, the bronchoscope is reintroduced to assess effectiveness. Patients may need to return for subsequent dilatations as needed.

Complications, although rare, include bronchospasm and atelectasis. Excessive balloon inflation may cause laceration or rupture of the airway, producing hemorrhage, pneumothorax, pneumomediastinum, or mediastinitis.

Common nursing considerations include the following: since these interventional procedures are highly specialized, all nursing staff and physicians working with these patients should be trained, and should be aware of the risks and complications associated with the procedure.

Common risks associated with bronchoscopies include discomfort and coughing (have lidocaine 1 percent available), pneumothorax (have a chest tube set up in the room), reduced oxygen (have supplemental oxygen supplies available in case of emergency, and monitor oxygen saturation), and bleeding (have medications ready such as lidocaine 2 percent with epi, Afrin nasal spray, and normal saline for irrigation and monitor vital signs). Notify the physician prior to the procedure if the patient is on any blood thinning medications that weren’t stopped.

It is important that the patients are instructed on the signs and symptoms of complications post-procedure. If they should experience any type of respiratory difficulty or bleeding they should come to the emergency room or call 911.

Conclusion

Interventional bronchoscopy has come a long way in the last 20 years. The majority of patients are able to be treated on an outpatient basis depending on their underlying respiratory disease and function.

Laser therapy, electrocautery, and APC produce rapid thermal tissue destruction; photodynamic therapy produces a non-thermal phototoxic reaction that leads to cell death; and cryotherapy involves the repeated freeze and thaw cycles for tissue destruction. With all these tissue-destroying interventions, there often needs to be long-term stabilization of the airways. Therefore, stent placement and balloon dilatation may be useful and sometimes necessary.

Linda M. Hylind, BS, RN, has been a clinical endoscopy nurse for 21 years and a nurse for 29 years. Angela Palmer, RN, CGRN, has been an endoscopy nurse for 18 years and a nurse for 21years. Both nurses work at the Johns Hopkins Hospital in Baltimore in the gastroenterology division, in the endoscopy unit for the department of medical nursing. They assist with diagnostic and interventional bronchoscopies and endoscopies.


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