11: Medical Thoracoscopy

CHAPTER 11
Medical Thoracoscopy
Section A: Rigid Thoracoscopy


Matthew Evison1, Ambika Talwar2, Ahmed Yousuf3 and and Mohammed Munavvar4


1 Wythenshaw Hospital, Manchester, UK


2 Churchill Hospital, Oxford, UK


3 Glenfield Hospital, Leicester, UK


4 Royal Preston Hospital, Preston, UK


The diagnosis and management of pleural disease is a frequent challenge for general and respiratory physicians. A common clinical scenario is the unilateral undiagnosed exudative pleural effusion, which is caused by malignancy in a large number of cases (42–77%). The burden of pleural disease is increasing with an estimated 50 000 new cases of malignant pleural effusion in the UK each year. This equates to 250 new cases per year in an average district general hospital.


Role of medical thoracoscopy


Medical thoracoscopy refers to the percutaneous insertion of a camera into the pleural cavity (usually into pleural fluid), under local anaesthetic and conscious sedation. It is minimally invasive and, once the pleural fluid has been drained, allows the operator to directly visualise the pleura and identify any abnormal areas suitable for biopsy. These biopsies can then be taken under direct visualisation. It is simultaneously a therapeutic procedure, allowing drainage of the fluid, and talc poudrage pleurodesis if appropriate. Direct visualisation of the pleural cavity also allows identification of any intrapleural adhesions that may be broken down and removed to aid complete expansion of the lung.


In undiagnosed exudative pleural effusions, pleural aspiration will yield a diagnosis in less than half of all cases. Blind percutaneous pleural biopsy only increases this yield by a small fraction, leaving a large proportion without a definitive diagnosis. Medical thoracoscopy dramatically increases the diagnostic yield to 96%. It is also the most effective procedure to achieve complete drainage of pleural fluid and to prevent recurrence of the effusion (84% pleurodesis success rate at 1 month, compared with 60% success rate with talc slurry via a chest drain), although current randomised data do not suggest an advantage for talc poudrage over talc slurry.


Medical thoracoscopy is also effective in the diagnosis and management of tuberculous pleurisy (and sometimes pleural infection). In addition, specialist thoracoscopic practitioners utilise medical thoracoscopy for the management of pneumothorax, lung biopsies and sympathectomy.


Who should undergo a thoracoscopy?


Medical thoracoscopy should be considered in any patient with an undiagnosed exudative pleural effusion. This procedure avoids the risks of general anaesthetic and single lung ventilation required for surgical diagnostic strategies (VATS). It is also a possible option for patients for whom video‐assisted thoracic surgery (VATS) is precluded because of comorbidity or poor prognosis.


A summary of the indications and contraindications for medical thoracoscopy is shown in Table 11.1.


Table 11.1 A summary of the indications and contraindications for medical thoracoscopy.
























Indications Relative contraindications
Undiagnosed exudative pleural effusion Obliterated pleural space
Suspected mesothelioma Extensive pleural adhesions
Staging of pleural effusion in lung cancer Bleeding disorder
Treatment of recurrent pleural effusions with pleurodesis Hypoxia (O2 sats <92% on air)
Pneumothorax requiring chemical pleurodesis as an alternative if patient unfit for surgery Unstable cardiovascular disease

Persistent uncontrollable cough

Types of medical thoracoscopy


Medical thoracoscopy can be performed using the rigid and semi‐rigid thoracoscope. The choice of instrument depends on operator experience and preference.


Rigid thoracoscopes allow a wide field of view of the thoracic cavity and permit larger sized pleural biopsies. The semi‐rigid thoracoscope has a similar design to a bronchoscope and therefore may be more ‘familiar’ to respiratory physicians. However, the working channel is narrower than the rigid scope, allowing smaller biopsies to be obtained and a narrower field of view. Nonetheless, good diagnostic yields have been reported using both instruments (see Section B).


Medical thoracoscopy is performed with local anaesthesia and conscious sedation by operators with the appropriate level of expertise. The procedure should be performed in an operating theatre, endoscopy suite or clean treatment room depending upon the resources available. Full patient resuscitation facilities should be available.


A step‐by‐step guide to medical thoracoscopy


An illustrated guide to the procedure is described. The differences in semi‐rigid and rigid thoracoscopy are highlighted in the text and figures. Much of this guide is based on expert opinion in the UK and is therefore not always evidenced based.


Patient preparation and consent


It is good practice to use the WHO checklist just before commencing the procedure. These are the principal elements to check:



  • Patient should have written information >24 hours before the procedure and written consent prior to the procedure by a doctor with the appropriate level of expertise.
  • Full blood count (FBC), coagulation profile, renal function and glucose (where indicated).
  • Up‐to‐date chest radiograph and any CT scans available.
  • Check the site of the procedure just prior to starting; the site of procedure should be drawn with a skin marker on the patient.
  • Preprocedure thoracic ultrasound to confirm the presence of pleural fluid is advisable.
  • Nil by mouth for at least 4 hours pre‐procedure.
  • An intravenous cannula in the arm on the same side as the thoracoscopy to make repeated administration of sedation during the procedure easier.
  • Pre‐medication with analgesia, such as paracetamol or ibuprofen.
  • Prophylactic antibiotics such as 1.2 g IV co‐amoxiclav are used by some centres, although this has not been subject to formal study.
  • Baseline oxygen saturations, pulse, BP, temperature.
  • The patient should be monitored with pulse oximetry, BP and three‐lead ECG throughout the procedure.

Procedure


Full aseptic technique should be observed throughout the procedure.



  • The patient is positioned in the lateral decubitus position (disease side up) and a thoracic ultrasound performed to confirm the presence of fluid and a suitable puncture site (usually in the mid axillary line).
  • Sedation is administered with dose titration and allowed time to take effect.
  • Oxygen (2–4 L/min) is administered via nasal cannulae.
  • Skin is cleaned with an alcohol‐based skin sterilising solution over the whole hemithorax including the axilla. A sterile drape should be placed over the patient, leaving a small exposed area through which the procedure is performed.
  • Local anaesthesia infiltration and confirmation of the presence of pleural fluid with needle aspiration.
  • A 1 cm incision is performed, following the orientation of the ribs at the thoracoscope insertion point.
  • Modified horizontal mattress suture should be inserted; this will act as a closing suture when the post procedure chest drain is removed.
  • Blunt dissection through the intercostal space into the pleural cavity (Figure 11.1).
  • Once the pleural space is entered, a 7 mm trocar or introducer should be gently eased into the pleural cavity to create a port of entry (Figure 11.2).
  • Pleural fluid is then aspirated with a soft suction catheter (Figure 11.3).
  • As pleural fluid is removed, air can enter the pleural space through the port to keep the lung deflated, preventing rapid re‐expansion of the lung.
  • The pleural cavity is then inspected by passing the semi‐rigid thoracoscope (Figure 11.4a) or rigid scope (Figure 11.4b) through the port. Images from a rigid scope are shown in Figure 11.5.
  • Parietal pleural biopsies are then taken at appropriate sites under direct vision using the optical biopsy forceps (Figure 11.6).
  • Talc poudrage can be performed if malignant aetiology is strongly suspected. In semi‐rigid thoracoscopy, this can be performed under direct visualisation. With the rigid approach, the thoracoscope is removed from the port and the talc is delivered into the pleural cavity if a one‐port technique is used (Figures 11.7 and 11.8).
  • The thoracoscope is then removed and a chest drain (at least 20 Fr) is inserted through the tract and sutured in place. This allows removal of air from the pleural space and complete re‐expansion of the underlying lung (Figures 11.9 and 11.10).
Lateral (left) and top (right) views of blunt dissection into the pleural cavity.

Figure 11.1 Blunt dissection into the pleural cavity.

Image described by caption.

Figure 11.2 Trocar insertion.

Image described by caption.

Figure 11.3 Insertion of suction catheter and pleural fluid drainage.

Image described by caption.

Figure 11.4 Insertion of (a) semi‐rigid scope; (b) rigid scope.

Image described by caption.

Figure 11.5 Inspection of pleural surface using rigid scope: (a) normal pleura; (b) diffuse pleural nodularity seen in malignancy.

Forceps expanding (left) and contracting (right) taking pleural biopsies.

Figure 11.6 Taking pleural biopsies (rigid approach, single port).

Image described by caption.

Figure 11.7 Talc poudrage. Image from rigid scope approach, post poudrage.

Image described by caption.image

Figure 11.8 Talc poudrage: (a) under direct vision using semi‐rigid approach; (b) image taken from rigid scope approach.

A man in lab suit standing while holding the thoracoscope inserted into the exposed area of the person's chest covered with drape.

Figure 11.9 Chest drain insertion.

A person lying covered with drape. The exposed area of the chest is attached with drain. To the person's side is a man standing, wearing lab suit.

Figure 11.10 End of the procedure.


Other considerations


Induction of pneumothorax


Safe thoracoscopy requires there to be a large pleural space between the lung and chest wall. In cases where there is little pleural fluid, a pneumothorax can be induced to increase the size of the pleural cavity. This procedure requires advanced expertise.


Second entry port


A second entry port may be required in cases where it may be technically challenging to obtain pleural biopsies via a single port.


Post procedure care


Medical thoracoscopy can be performed as a day case procedure when talc poudrage is not conducted, with discharge after 4 hours of observation for procedures that do not involve talc pleurodesis. However, the decision for overnight stay should be evaluated on a case‐by‐case basis.



  • Monitor oxygen saturations, pulse, BP and temperature every 15 minutes for the first hour after the procedure.
  • The chest drain should be on free drainage initially, but continuous suction may be required when the drain stops bubbling and if the lung has not re‐expanded.
  • Analgesia with opioids and/or non‐steroidals is frequently required.
  • Deep venous thrombosis (DVT) prophylaxis (increased coagulopathy with talc pleurodesis).
  • Mobile chest radiograph on the day of and day after procedure if the chest drain is kept in situ.
  • Remove the chest drain when the lung is re‐inflated on chest radiograph and there is no evidence of ongoing air leak from the chest tube.

Diagnostic accuracy of medical thoracoscopy


The diagnostic accuracy of medical and surgical thoracoscopic biopsy in malignant pleural effusion is approximately 93%.


There are two randomised controlled trials comparing rigid thoracoscopy with semi‐rigid thoracoscopy, and they concluded that the diagnostic accuracy of the two techniques was comparable. In 2006, two centres in the UK compared the two types of scope (27 patients undergoing rigid thoracoscopy and 41 patients undergoing semi‐rigid thoracoscopy). The diagnostic accuracy was found to be 26/27 patients in the rigid thoracoscopy group (96.2%) and 38/41 (92.6%) in the semi‐rigid thoracoscopy group.


Complications and adverse events with medical thoracoscopy


Mortality rates are low (<0.01% of cases). Box 11.1 lists the potential minor and major complications.

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Jun 4, 2019 | Posted by in RESPIRATORY | Comments Off on 11: Medical Thoracoscopy

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