INTERVENTIONAL PULMONOLOGY

The Art of Bronchology

The birth of bronchoscopy in humans began in 1897 when the famous German laryngologist Gustav Killian, known as the "father of bronchoscopy", used a metal rod to remove an aspirated pork bone form a man's right main bronchus. Chevalier Jackson of Philadelphia then modified the rigid bronchoscope (RB) in 1904 by adding a direct ocular mechanism, suction tube, and distal tip illumination (1). RB was used to examine airways until late 1967, when Shigeto Ikeda of the National Cancer Institute, Tokyo, began using the flexible fiberoptic bornchoscope (FB) (1). The bronchoscope has contiued to gain utility primarily as a diagnostic tool. Howerver, it has also become a popular modality for many therapeutic purposes.


Indication for rigid bronchoscopy

Indications for rigid bronchoscopy are easily enumerated. They include the standard indication for foreign body removal, although most foreign bodies today can be removed using a flexible fiberoptic bornchoscope. Many experts would agree that some foreign bodies, such as nuts, dental bridges, impacted teeth, and coins, are more readily removed, bleeding is more easily controlled, and foreign objects are more easily grasped with large forceps.
Hemoptysis is another potential indication for rigid bronchoscopy. In patients whose bleeding is maassive and not controlled using the flexible thoracoscope with its small 2.0 mm suction channel, access to the airways through the rigid tube allows selective intubation and insertion of large suction tubing to remove blood clots: it also allows the operator to stop the bleeding by laser photocoagulation tamponade techniques ( with forceps, sponges, or the rigid assured throughout the procedure, and access to the airway is not hinderered by a small endotracheal tube. When using the rigid bronchoscope for massive hemoptysis, long ventilating tubes, usually of 12 -mm diameter , should be inserted to gain greatest access to both the proximal and distal airways.
Finally, the rigid bornchoscope is an ideal instrument for the many therapeutic procedures available to interventional pulmonologists and surgeons today. This include, but are not limited to : (1) laser photocoagulation, electrocauterization, or argon plasma coagulation of exophytic tumors, granulation tissue, or benign lesions such as papillomas, hemartomas, lipomas, and adenomas; (2) laser resection of obstructive malignant melanoma, and brochogenic carcinoma; (3) laser resection of benign tracheal and bronchial strictures, such as those that occur from post-intubation injury, tracheostomy, lung transplantion, inhalation injury, and benign diseases such as Wegender's granulomatosis, turberculosis, Klebsiella rhinoscleroma, and amyloidosis; and (4) stent insertion to palliate extrinsic compression of the tracheobronchial lumen form either malignant or benign disease processes.


Rigid bronchoscope and accessory instruments

The rigid bronchoscope is a rigid, straight, hollow metallic tube made of stainless steel. Manufacturers produce tubes in various diameters. The wall thickness of each tube is about 3 mm, and lengths may vary from a few inches (such as those tubes used in children) to more than 15 inches.The external diameter of the rigid bronchoscope may vary depending on th manufacturer. For adults,. most tubes are at least 8 mm wide and are usually of uniform diameter form proximal to distal end Most rigid bornchoscopists prefer using a 10 mm or 12 mm rigid tube, which coforms nicely to the diameter of both the adult trachea and main bronchi.
Some bronchoscopes have a beveled distal extrmity that facilites mobilization of the epiglottis during intubation. Although some bornchoscopic tubes ar almost oval, most are round and have external side pots to permit introduction of suction catheters and lser fibers and to allow ventilation. In addition, some bronchoscopes have distal side ports that allow ventilation of the contralateral lung while working within an ipsilateral main bonchus.
Therefore, rigid bronchoscopes can be referred to as ventilating or non ventilating based on the presence or absence of such distal side ports. Nonventilating tubes are used primarily in the trachea. The major manufacturers and distributors of rigid bronchoscopes include the EFER Company (La Ciotat, France), the Richard Wolf Company (Germany), and the Karl Sotz Company (Germany). Each manufacturer provides accessory instruments, light sources, and rigid telescopes for use during bronchoscopic procedures.
Ilumination through the rigid telesccope introduced into the rigid bronchoscope occurs by the use of fiberopic light cables attached to a cold light or Xenon light source. Increasingly, a video camera can be attached to the eyepiece of the rigid telescope, projecting images of the airway Onto a television Screen. Videobronchoscopy has nearly become standard of practice and is ideal for teaching, documenting procedures, and allowing bronchoscopy assistants and anesthesia staff to follow the action.
Accessory instruments often used during rigid bronchoscopy include biopsy forceps of various lengths and shapes, suction tubing, rigid and flexible foreps specific to various procedures, laser fibers, electrocautery probes and snares, and specially designed tubes and instruments used to insert tracheobronchial stents.


History of thoracoscopy

Many artificail pneumothoraces would not be complete because of adhesions at the chest wall. In response to this limitation of the technique, Hans Christian Jacobaeus of the Seramiferlasarettet hospital of Stockholm performed the first operative thoracoscopy to divide these adhesions and published his new technique in a paper entitled "Concernig the Possibility of Using a Cystoscope in the Examination of Serous Cavities". He described his two-cannulae technique, first in the pertioneum (laparoscopy) and then, only at the end of his article, in the pleura (thoracoscopy). A line diagram illustrated his simple equipment.
Jacobeaus' technique was to sedate his patients with bromide or luminal, mark at fluoroscopy the exact position of the adhesion on the chest wall, insert his thoracoscope nearby, insert the galvanocautery in the anterior axillary line, and heat in only to a red gloq. he classified adhesions by their position, shape, and their surgical difficulty. he reported that 75% of his patients had complete collapse of th cavities, 67% had a good clinical result; but 24% were classified as "incomplete cauterization". In addition to the diagnostic potential, Jacobaeus hoped, by means of thoracoscopy to achieve prognostic information.
Even though Jacobaeus primarily developed thoracoscopy as a diagnostic procedure, it was applied during the ensuring 40 years on a worldwide scale, almost exculsively for the lysis of pleural adhesions by means of thoracocautery.


Thoracoscopy today

About 1950, with the advent of antibiotic therapy for tuberculosis, the era of pneumothorax therapy came to an end. In addition, the number of tuberculous patients gradually decreased and other diseases became more and more important ot the Pulmonologist.
Consequently, between 1962 and 1996, a generation of physicians already familiar with the technique, began to use it on a much broader basis for evaluating many pulmonary diseases.
The indications were expanded by using biopsy for localized and diffuse lung diseas. Satler and his associates from 1937 to 1981, applied thoracoscopy to the complete spectrum of pulmonary disease and published data obtained by systematically studying large numbers of patients, thus taking the responsibility for both the development and dissemination of this technique.
The proportion of the thoracoscopy to bornchoscopy has remained roughly 1:7. This relationship is, however, not representative of similar developments thoughout the world. Other diagnostic methods as well as the sparation between medical and surgical pulmonolgy has periodically pushed thoracoscopy into the background.
Due to technical improvements and trend towards less invasive procedures, thoracoscopy was rediscovered by thoracic surgeons at the beginning of the the 1990's and termed "Surgical" thoracoscopy, which is more precisely know as Video-Assisted Thoracic Surgery (VATS). Interestingly this revival has also supported the introduction of "medical" thoracoscopy into the scope of respiratory physicians, in particular in the United States where, according to a national survey in 1994, already more than 5% of all Pulmonologists were applying medical thoracoscopy. In Europe, thoracoscopy is intrinsic in the training program of Pneumology.


Diagnostic Thoracoscopy

The use of thoracoscopy has been resumed as a result of considerable progress in modern techniques, particularly in the following areas: (1) Endoscopic telescopes have been greatly improved, and now have an extremely high optical quality inspite of their small diameter. (2) Adequate instruments, including video camera, forceps, endoscopic scalpel, stapler, and laser, enable the physiian or surgeon to carry out interventional thoracoscopy in edoscopic pleurectomy, pulmonary biopsy, blebs resection, mediastinal lymph node biopsy, pericardial window or biopsy, dorsal sympathectomy, pleural brushing, and so on. (3) Progress in anesthesia allows for a broad choice of agents that range form local anesthetics in outpatients to general anesthesia.
Thoracoscopy, while allowing ful exploration of the thoracic cavity, is much less invasive and incapacitating than thoracotomy. Complications are uncommon and rarely occur when the procedure is performed by one who has mastered the technique.


differences between video-assisted thoracoscopic surgery (vats) and medical throacoscopy

Thoracoscopy offers the pulmonologist the ability to obtain a biopsy specimen from the pleural surfaces as well as provides better understanding of pleural diseases. The entire chest cavity and lung could be examined, and in occasion minute emphysematous blebs responsible for pneumothoraces, could be seen. This information is not always detectable by CT.
Indeed the intents of a pulmonologist are very different form those of thoracic surgeons, this is to perform thorcic surgery in a minimally invasive manner. Video-assisted thoracic surgery is performed in an operating room almost exclusively under general anesthesia and single lung ventilation, allowing the collapse of the lung on the examined site. Usually, multiple ports of entry with different disposable intruments, are used. An additional larger incision may be needed to remove larger tumors or pieces of tissue. VATS has been used to perform stapled lung biopsy, nodule resection, lobectomy, and pneumonectomy. It has been used for pericardial windows, trans-thoracic vagotomy, and for resection of peripheral benign and metastatic nodules. Other successfully performed procedures include repair of bronchopleural fistula and evaluation of mediastinal tumors or adenopathy.
In contrast, medial thoracoscopy is performed by Pulmonologists in an endoscopy suite or operating room depending on the local availability of the appropriate facility, local anesthesia, conscious sedation, and requirement of one or two ports of entry using simple non-disposable instrumentation. The objective is to diagnose pleural diseases. Thoracoscopy may lead to evaluation of innovative biological therapies in the treatment of pleural diseases. Finally, thoracoscopy provides an efective method for performing pleurodesis.