ANAESTHESIA FOR THORACOSCOPY, VATS, BAL,MEDIASTINOSCOPY AND ESOPHAGOSCOPY

1. ANAESTHESIA FOR THORACOSCOPY, VATS, BAL,MEDIASTINOSCOPY AND ESOPHAGOSCOPY BY- DR SUCHIT KHANDUJA MODERATOR- DR AJAY SOOD

2. MEDICAL THORACOSCOPY

3. History • Thoracoscopy was introduced together with laparoscopy in 1910 by Hans-Christian Jacobaeus. • Jacobaeus initiated the therapeutic application of thoracoscopy for lysis of pleural adhesions • With the advent of anti-tuberculosis drugs, thoracoscopy was abandoned for several decades. • Recent technologic advances such as improved optical and video technology have revitalized the use of this procedure as a diagnostic and therapeutic tool.

4. History • Excellent results of laparoscopic surgery and the tremendous advances in endoscopic technology stimulated many thoracic surgeons to develop minimally invasive techniques, which were termed therapeutic or surgical thoracoscopy, as well as video-controlled or video-thoracoscopic surgery, or video-assisted thoracic surgery (VATS). • Pleuroscopy (medical thoracoscopy) is considered as a part of the field of interventional pulmonology.

5. INDICATIONS OF MEDICAL THORACOSCOPY • Pleuroscopy • Pleural effusions • Staging of lung cancer • Staging of diffuse malignant mesothelioma • Pleurodesis by talc poudrage

6. Contraindications Absolute: • Size of free pleural space <6-10 cm usually due to extensive adhesions. • Respiratory insufficiency requiring ventilatory support. • Pulmonary arterial hypertension • Uncorrectable bleeding disorders. Relative: • Intractable cough. • Hypoxemia. • Unstable cardiovascular status.

7. Techniques • Pleuroscopy is an invasive technique that should be used only when other, simpler methods do not provide the diagnosis. • The technique is actually very similar to chest tube insertion by means of a trocar. • There are two different techniques of diagnostic and therapeutic pleuroscopy.

8. Techniques • The first method uses a single entry site, usually with a 9-mm trocar, for a thoracoscope with a working channel for accessory instruments and optical biopsy forceps that is employed under local anesthesia. • In the other technique, as used by Jacobaeus for lysis of adhesions, two entry sites are used: one with a 7-mm trocar for the examination telescope and the other with a 5-mm trocar for accessory instruments, including the biopsy forceps. • General anesthesia is preferred for above

9. Equipment A, Trocar and cannula with valve. B, Single-incision thoracoscope (9 mm diameter). C, Biopsy forceps with straight optical device. D, Magnified view of optical device and forceps in the thoracoscope shaft ready for biopsy. • The single-entry-site technique is usually done with a 9-mm diameter trocar and a cannula with valve. • The two-entry-site technique uses a 7-mm trocar for the first site of entry, with appropriate telescopes and forceps, and similar accessory instruments. For the second site of entry, a 5-mm trocar is used.

10. Equipment Semirigid pleuroscope with biopsy forceps • It has the advantage that the skills involved in operating the instrument are already familiar to the practicing bronchoscopist. • Its disadvantages compared to rigid thoracoscopic instruments are the smaller biopsy specimens. However, the flexible tip allows very homogeneous distribution of talc on all pleural surfaces.

11. Equipment • The procedure suite should be equipped with monopolar and, if possible, bipolar electrocoagulation as well as equipment for resuscitation and assisted ventilation, electrocardiography, blood pressure monitoring, defibrillator and as well as oxygen and vacuum generators.

12. PREOPERATIVE PREPARATION • Radiologic evaluation include • P-A and lateral chest radiograph. • Ultrasound for localization of the pleural fluid and for diagnosis of fibrinous membranes or adhesions in the pleural space. • CT scan is not mandatory, but can be helpful in certain situations such as loculated empyema and localized lesions of the chest wall or diaphragm. • ABG • ECG • Clinical laboratory tests

13. Pleuroscopic Technique • The site of introduction of the pleuroscope depends in part on the location of abnormalities to access and the location of potentially hazardous areas to avoid. • The region of the diaphragm is unsuitable. • The trocar is generally introduced in the lateral thoracic region between the mid- and anterior axillary line in the fourth to seventh intercostal space.

14. Area is prepared with cleansing agent • Local anesthesia is administered and after making a small skin incision, the trocar is advanced with a fairly forceful corkscrew motion until the detectable resistance of the internal thoracic fascia has been overcome. • The cannula of the trocar should lie at least 0.5 cm within the pleural space.

15. Pleuroscopic Technique • Pleural effusions should be removed completely by using a suction tube that does not fully occlude the cannula • After complete removal of the effusion, or in cases without effusion, the optical device is introduced through the cannula, and the pleural space is then inspected. • Biopsies of the pleura and, if needed, of the lungs, can be carried out most easily and safely by means of the lung biopsy forceps. • Although a single site of entry is generally sufficient, a second site may be useful for biopsies or to perform coagulation

16. Anesthesia • Pleuroscopy by the single-entry-site technique is usually done under local anesthesia with premedication, using an antianxiolytic, a narcotic, or both (e.g., midazolam and hydrocodone). • Additional pain medication should be given during the procedure, as required. • An excellent alternative is sedation by propofol with or without premedication. • General anesthesia with intubation and ventilation is not necessary for pleuroscopy

17. Complications Mortality - 0.01-0.25 % Morbidity: • Desaturation during procedure (↓ LA) – <2% • Persistent post-operative air leak (>7d) – <2% (pts with spontaneous pneumothorax). • Subcutaneous emphysema ( 0.5%) • Rare – benign cardiac arrythmias, transient hypotension and seeding of pathology in patients with malignant mesothelioma.

18. VATS

19. Video-assisted Thoracic Surgery(VATS) • VATS uses small incisions to perform therapeutic interventions in the chest without spreading the ribs. • VATS requires an operating room, general anesthesia with single-lung ventilation, more than two (usually three) entry sites, and complex instruments. • Overall, it is a more invasive and expensive technique with a higher risk than pleuroscopy • In experienced hands and in the proper setting, VATS is less invasive, is less expensive, and has a lower risk than open procedures.

20. Indications Lung biopsy • Lobectomy • Decortication • Lung volume reduction surgery Pleura procedures • Pleurectomy (pneumothorax) • Drainage/decortication (empyema stage III) Mediastinal procedures • Resection of mediastinal mass • Thoracic lymphadenectomy • Thoracic duct ligation •  Pericardial window • Sympathectomy Esophageal procedures • Excision of cyst, benign tumors • Esophagectomy • Anti-reflux procedures

21. General Procedure • The trocar and the camera are placed in the midaxillary line in approximately the eighth intercostal space. • Most of the surgeons use a reusable 5-mm trocar and a 30-degree, 5-mm thoracoscope. • A 2-cm incision is made in about the sixth intercostal space in the mid-clavicular line. • An additional incision is made in the fourth intercostal space in the midaxillary line. • A variety of equipment is available for VATS procedures.

22. Basic instrumentation for VATS • “Three-chip” endoscopic video camera and high-definition television monitor • Operating thoracoscope (with 5-mm biopsy channel) • Three standard-length ringed forceps • Suction-irrigation system 10 mm diameter • Endoscopic hook cautery (5 mm) with trumpeted suction • Standard electrocautery unit with extended tip for application through intercostal access site • Landreneau “Masher” set • Bulbed syringe (60 ml) • Standard Metzenbaum scissors (10–12 in.) • Standard University of Michigan Mixner clamp (10–12 in.) • Standard-sized and pediatric Yankour metal suckers • Standard 28-French chest tubes (straight and right angled) and closed drainage system

23. ANAESTHETIC IMPLICATIONS • Thoracoscopic surgery can be performed under local, regional, or general anesthesia with two-lung ventilation or OLV. • For minor diagnostic procedures VATS can be done in the awake patient. • Intercostal nerve blocks performed at the level of the incision and two interspaces above and below provide adequate analgesia. • Partial collapse of the lung on the side of surgery occurs when air enters the pleural cavity. • When using local anesthesia with the patient awake, it is hazardous to insufflate gases under pressure into the hemithorax in an attempt to increase visualization of the pleural space. • Changes in Pao2, Paco2, and cardiac rhythm are usually minimal during the procedure when it is performed under local anesthesia and the patient is breathing spontaneously. • It is recommended that a high Fio2 is delivered via a facemask to overcome the shunt due to the loss in lung volume caused by the unavoidable pneumothorax.

24. For most invasive procedures VATS is performed under general anesthesia with a DLT or a bronchial blocker to achieve OLV. Lung collapse will take longer when a bronchial blocker is used; if rapid lung collapse is needed, a DLT may be the preferred choice. If the procedure is short in duration and the lung needs to be deflated for only a brief period, blood gases are not routinely monitored during the procedure. However, for patients undergoing prolonged VATS procedures such as lobectomy or for patients with marginal pulmonary status, an arterial line and measurement of arterial blood gases is required. Paravertebral and intercostal blocks have been used with a single dose of local anesthetics and have been shown to reduce pain after thoracoscopic surgery for 6 hours

25. Contraindications and complications same as medical thoracoscopy

26. BRONCHALVEOLAR LAVAGE

27. BRONCHOALVEOLAR LAVAGE General indications: • Non-resolving pneumonia • Diffuse lung infiltrates (interstitial and/or alveolar) • Suspected alveolar hemorrhage • Quantitative cultures for ventilator associated pneumonia • Infiltrates in an immunocompromised host • Exclusion of diagnosable conditions by BAL, usually infection • Research

28. BAL can be diagnostic in the appropriate clinical setting for: • Alveolar hemorrhage • Malignancies • Lymphangiticcarcinomatosis • Bronchoalveolar carcinoma • Other malignancies • Infections • PCP • Mycobacterial • Bacterial • Fungal • Viral

29. Equipment • Flexible bronchoscope/DLT • Sterile collection trap • Suction tubing • Sterile saline • Vacuum source • Syringe • Optional 3 way stop-cock • Lidocaine 1-2%

30. Preparation and Anesthetic implications • Obtain informed consent. • If an outpatient procedure, the patient should be accompanied by a person designated to drive the patient. • BAL should be planned to be performed prior to any other bronchoscopic procedure. • Review radiographs to determine ideal site of alveolar lavage. • In diffuse infiltrates, the right middle lobe (RML) or the lingula in the supine patient is preferred.

31. Prepare bronchoscope/DLT, collection trap, and tubing. • Prepare supplemental oxygen and monitoring equipment. • ECG, pulse-oximetry, NIBP • Premedicate with bronchodilators and/or warm the saline solution for those at risk for bronchospasm. • Position patient, preferably in supine position when approaching RML or lingula. • Apply monitors and supplemental oxygen. • Sedation with a benzodiazepine and a narcotic will allow patient comfort and minimize cough reflex.

32. Radiologic imaging, CT, and ventilation-perfusion scans help to determine the most impaired lung, which will be lavaged first. General anesthesia is induced and maintained with intravenous infusions as for lung transplantation.

33. Airway management is with a left-sided DLT. • Precise placement of the tube is confirmed by fiberopticbronchoscopy • Air-tight isolation is determined by monitoring inspired and expired tidal volumes with side-stream spirometry. • Tube dislodgment and flooding of the nonlavaged lung is a major complication of this procedure.

34. Specifically during lavage of the left lung, the pressure of saline in the lung will tend to push the bronchial cuff of the DLT proximally. • To prevent this it is recommended that the anesthesiologist maintain his or her hand on the DLT, securing it firmly at the patient's mouth, throughout the entire procedure. • The pulmonary compliance of the ventilated lung needs to be continuously monitored to diagnose any liquid spillage from the lavage lung.

35. The patient is kept in the supine position during the procedure. • To improve the effectiveness of the lavage, ventilation with Fio2 100% for a few minutes is initiated after induction to de-nitrogenate both lungs. • OLV is instituted with the nonlavage lung. • A disposable irrigation and drainage system is used to instill approximately 1 L of warm normal saline (37°C) into the lavage lung

36. The irrigating liquid is suspended 30 cm above the patient's mid-chest level to the lavage lung. • Thereafter, the saline is rapidly drained by gravity into a container positioned 60 cm below or with the assistance of a small level of suction (<20 cm H2O). • This process is repeated as needed until the effluent fluid is clear.

37. Chest physiotherapy—is applied during the filling and the drainage phases. • The use of flannel protects the patient's chest wall from trauma due to physiotherapy during the percussion. • If the cumulative total of the instilled fluid volume exceeds the drainage volume by more than 1000 mL a hydrothorax should be suspected

38. Oxygenation increases during the filling phase and decreases during the emptying • Changes are usually transient and well tolerated. • Inflation of a pulmonary artery catheter balloon in the pulmonary artery of the lavage lung while adding nitric oxide to the ventilated lung or the use of ECMO to maintain oxygenation and prevent hypoxaemia.

39. Usually 10 to 15 L is instilled and more than 90% is recovered, leaving a deficit of less than 10%. • At the end of the procedure the lavaged lung is thoroughly suctioned • A dose of furosemide (10 mg) is administered to increase diuresis of absorbed saline. • If the plan is to proceed to a lavage of the contralateral lung there is a period of at least 1 hour of two-lung ventilation.

40. After the procedure, after re-intubation with a single-lumen tracheal tube, inspection with fiberopticbronchoscopy is performed for suctioning. • Conventional ventilation with PEEP is continued, usually for less than 2 hours. • Alveolar infiltrates seen on the chest radiography immediately after lavage normally clear within 24 hours. • Observation in the intensive care unit for 24 hours is part of the routine procedure

41. Complications/Adverse events • No complications in up to 95% • Cough • Transient fever (2.5%) • Transient chills and myalgias • Transient infiltrates in most (resolves in 24 hours) • Bronchospasm (<1%) • Transient fall of lung function • Transient decrease in baseline PaO2 • Need for mechanical ventilation postoperatively.

42. ESOPHAGOSCOPY

43. ESOPHAGOSCOPY DIAGNOSTIC INDICATIONS • History of functional disease of esophagus • Radiological evidence of disease of esopagus • Suspected foreign body of esophagus • Asessment of caustic ingestion

44. THERAPEUTIC INDICATIONS • Removal of foreign bodies • Dilation of cardia and division of divericulum • Injection in varices

45. CONTRAINDICATION • Uncorrected medical disorder • For rigid esophagoscopy severe kyphoscoliotic disorder or cervical spondylitis

46. POSITIONING • Positioning is same as that for laryngoscopy and bronchoscopy • Table must have a flexible head rest • On occasion shoulder role may be heplful but pts head need to be extended during esophagoscopy

47. INSTRUMENTS A no. of flexible scopes are available which allow superior visualisation Rigid esophagoscope may be round or oval(hollinger or jesberg) with or without telescope.

48. ANAESTHETIC IMPLICATIONS • Preoperative sedation may be needed • With a flexible scope local anaesthesia is used with concomitant sedation • For children GA is used • For rigid esophagoscopy GA is preferred • Foreign body removal is done under GA • All such pts must be considered to be full stomach

49. Rapid sequence anaesthesia preferred in all such pts. • Once airway is secured higher degree of inhalational anaesthetic with muscle relaxation given to ensure minimal movement during procedure • Greater chances of extubation because of neck extension

50. Technique • Can be done under LA/GA • If GA is used intubation is first performed • Esophagoscopy canbe performed without laryngoscopy • The scope is passed along the post pharangeal wall to the level of arytenoids • Narrow horizontal slit seen posterior to larynx ,leading edge of esophagoscope passed into the slit and cricoid lifted anteriorly. • Scope then passed into lumen of esopagus