MEDIASTINAL MASS EXCISION REMOVAL

1. Anaesthesia for Mediastinal
Masses
DR ZIKRULLAH

2. AN OVERVIEW
• INTRODUCTION
• BOANDARIES
• DIVISION
• CONTENTS
• MASSES
• DIFFICULTIES DURING ANAESTHESIA
• PREOPERATIVE EVALUATION
• ANAESTHESIA FOR DEFINITIVE PROCEDURE

3. Introduction
 The mediastinum is the region in the chest
between the pleural cavities that contain the heart
and other thoracic viscera except the lungs.
 BOUNDARIES?????

4.  Boundaries
 Anterior - sternum
 Posterior - vertebral column and paravertebral
fascia
 Superior -thoracic inlet
 Inferior - diaphragm
 Lateral - parietal pleura

5. Sternal Angle
Thoracic inlet
Thoracic oulet
Boundaries of mediastinum
sternum
Thoracic vertebra

6. TS: Mediastinum
6
CS: Mediastinum

7. • Division of mediastinum??

8. Divisions of mediastinum
MEDIASTINUM
Superior
mediastinum
Inferior
mediastinum
Anterior
mediastinum
Middle
mediastinum
Posterior
mediastinum

9. Superior
Mediastinum
Posterior
Mediastinum
Anterior
Mediastinum
Middle
Mediastinum
Sternal
Angle
T4
T5
divided into superior mediastinum and inferior mediastinum by an imaginary line passing
through sternal angle anteriorly lower border of 4th thoracic vertebra posteriorly
Mediastinum divisions

10. CONTENTS OF THE MEDIASTINUM??

11. Superior Mediastinum
 It contains:
 Trachea
 Esophagus
 Blood vessels (large
veins & arteries)
(listed later)
 Nerves (listed later)
 Thoracic duct
 Thymus
 Lymph nodes

12. Superior mediastinum contents
Blood Vessels
Veins:
SVC
Lt & Rt brachiocephalic
veins,
Arteries:
Arch of Aorta
Brachiocepalic artery
Lt Common carotid
Lt subclavian artery

13. Superior Mediastinum
Nerves
1. Vagus nerve
2. Left
Recurrent
Laryngeal
nerve.
3. Phrenic
nerve.

14. Anterior mediastinum:
contains:
a. Thymus
gland
b. Lymph
Nodes
c. Fat.

15. Middle Mediastinum
Contents:
Heart enclosed in pericardium
Arteries: Ascending Aorta,
Pulmonary trunk with its Lt &
Rt branches
Veins: SVC,Pulmonary veins
Nerves: Phrenic, vagus nerve
Bifurcation of Trachea with
two principal bronchi
Tracheobronchial lymph nodes
15

16. 16
Posterior Mediastinum
Contents:
Oesophagus
Arteries
• Descending Aorta with its brs
Veins
• Azygos
• Hemizygos
• Accessory hemizygos
Nerves:
• Vagus
• Splanchnic nerves
Thoracic duct
lymph nodes
• Posterior mediastinal

17. • Mediastinal masses??

18. Mediastinal Masses
Compartment %
Malignant
Anterosuperior 59
Middle 29
Posterior 16
Mediastinal
division
Most common
tumors
Anterior-
superior
thymoma
middle lymphoma
posterior Neurogenic
tumors

19. Anterosuperior Masses
Thymus
• Thymoma
• Thymic carcinoma
• Thymic cyst
• Thymic carcinoid
• Thymolipoma
Mediastinal Lymphoma
• Hodgkin’s Lymphoma
• Non-Hodgkin’s Lymphoma
Mesenchymal tumors
Germ Cell Tumor
• Seminoma
• Non seminomatous Germ Cell
• Embryonal cell carcinoma
• Endodermal sinus tumor
• Choriocarcinoma
• Teratoma
• Mature
• Immature
Endocrine tumors
• Thyroid tumors
• Parathyroid adenoma

20. Middle mediastinal masses
Mediastinal Lymphoma
• Hodgkin’s Lymphoma
• Non-Hodgkin’s Lymphoma
Mesenchymal tumors
CYST:
• Bronchogenic cyst
• Thoracic duct
• Meningoceles
Cardiac & pericardial tumors
Tracheal tumors
vascular tumors
Lymphadenopathy
• Inflammatory
• Granulomatous
• sarcoidosis

21. Posterior mediastinal masses
Mediastinal Lymphoma
• Hodgkin’s Lymphoma
• Non-Hodgkin’s Lymphoma
Mesenchymal tumors
Neurogenic tumors
• Peripheral nerves
• Symphathetic ganglia
• paraganglia
ENDOCRINE TUMORS
ESOPHAGEAL TUMORS & CYSTS

23. DIFFICULTIES ENCOUNTERED
DURING ANAESTHESIA??

24. • Can compress the major airways.
• Carefully evaluated before subjecting them to
anaesthesia.
• Large mediastinal tumours with apparently
normal airways preoperatively,
• May develop an obstructed airway after
induction of GA.

25. • Life threatening airway compression can
occur even after an uneventful ETI.
• Emergency tracheostomy to relieve
obstruction may be required.
• In the presence of severe symptoms of
cardiorespiratory compression,
• such as, dyspnoea, orthopnoea, stridor,
syncope, SVCS.
• administration of GA may be fatal.

26. • Irreversible cardiorespiratory collapse can
occur with the use of:
• sedative premedication,
• Induction of anaesthesia, use of muscle
relaxants, initiation of IPPV,
• Making the patient supine, change of posture,
and tumour resection or manipulation.

27. • Preoperative evaluation and risk
assessment??

28. • Preop. evaluation and risk assessment
Includes:
• Clinical presentation,
• Radiological examination,
• Pulmonary function studies,
• Awake fibreoptic bronchoscopy and
• Echocardiography.

29. • Clinical presentation??

30. • Due to compression of the airway viz.,
trachea, main bronchi
• cough,
• stridor,
• dyspnoea,
• orthopnoea,
• postural dyspnoea, or cyanosis.

31. “superior mediastinal syndrome”
• Compression of the heart and its big vessels
may lead to-
• Cyanosis, syncope, and dysrhythmias.
• SVCS characterized by-
• Engorgement of the veins of the neck, right
upper arm, chest wall and
• Oedema of neck, head and upper arm and
mental obtundation may be present.

32. Radiological evaluation
• Chest X-ray,
• Computed tomography (CT) scan and
• Magnetic resonance imaging (MRI)

33. normal trachea (single arrow). Note : There is a mass on the right side and
the left bronchus is visible, (double arrow) and right one is not, suggesting
right bronchial compression

34. Chest radiograph (postero –anterior view), showing a large mediastinal
mass occupying the right side with tracheal deviation and compression of
the
distal trachea and carina

35. • CT scan quantifies-
• Measurement of the diameter,
• cross-sectional area,
• mediastinal thoracic ratio (MTR) and
• mediastinal mass ratio (MMR).

36. CT scan chest showing transverse section at the level of tracheal
bifurcation. Note the large mass occupying the entire right
hemithorax and
compressing the trachea

37. • Tracheal diameter :35% decrease in dia. Of
tracheobronchial lumen is associated with
respiratory symptoms.
• >50% decrease may be associated with
complete airway obstruction during
induction or emergence from GA.

38. • Tracheal CSA : tracheal area = age in years / 9,
plus 0.35 cm2.
• TA,relative to the predicted TA can be
calculated as
• % TA = measured area / predicted area x100.
• Less than 50% of the predicted area have
higher risk of respiratory complications and
recommended that these patients should not
receive GA.

39. • Mediastinal thoracic ratio (MTR) calculated by
comparing the size of the mediastinal mass
with the thoracic diameter.
• >50% has higher risk of periop. respiratory
complications.
• Mediastinal mass ratio (MMR) maximum
width of the mediastinal mass relative to the
maximum width of the mediastinum,
• measured by the CT scan.

40. Pulmonary function study
• Peak expiratory flow rate (PEFR) :reflects
central airway diameter.
• <50% of the predicted PEFR associated
with significant anaesthetic complications.
• Flow volume loop - It graphically relates
the instantaneous airflow rate to the lung
volume.
• Helps to differentiate between the
extrathoracic and the intrathoracic airway
obstruction.

41. • Intrathoracic airway obstruction
demonstrated by appearance of expiratory
flow truncation (expiratory limb plateau).
• Extrathoracic airway obstruction have
diminished flow in the inspiratory phase
(inspiratory plateau).
• It is a dynamic, minimally invasive, and
most sensitive test.

42. Flow volume loop showing reduced vital capacity and expiratory
flow rate. Note the expiratory limb plateauing (arrow) indicative
of an intrathoracic airway obstruction

43. Awake fibreoptic bronchoscopy
• Assess the degree of obstruction due to
extrinsic compression or invasion by the
mass.
• Echocardiography Tumour enveloping the
heart and infiltrating the pericardium
• Develop refractory cardiovascular collapse
under the effects of GA.

44. • Incidence of complications related to airway
obstruction with the use of GA in patients
with mediastinal masses reported to be 7% to
18%.
• Patients with large mediastinal masses
present unique problems to the
anaesthesiologist.
• Sudden refractory cardio-respiratory collapse
can occur on induction of GA in symptomatic
as well as asymptomatic patients.

45. • Patients present for performing the biopsy or
definitive resection via sternotomy or
thoracotomy.
• The anaesthesiologist should always be
prepared to deal with an emergency even in
patients who have no symptoms or evidence
of airway obstruction.

46. • Mechanism of airway compression during
GA??

47. • GA exacerbates extrinsic airway compression
by various mechanisms;
1) By reducing functional residual capacity
(FRC), as the lung volume is reduced by
about 500 ml –1500 ml
• due to increased abdominal muscle tone
and decreased inspiratory muscle tone.

48. 2) Loss of spontaneous diaphragmatic
movement under GA with the use of muscle
relaxants
• Eliminates the normal transpleural pressure
gradient as compared with the spontaneous
inhalational anaesthesia.
3) Relaxation of the tracheobronchial smooth
muscles enhances extrinsic compressibility of
the airways.

49. • 4) The supine position causes an increase in
central blood volume, which may increase
tumour blood volume and its size.
• rapid tumour enlargement due to
haemorrhage or congestion within the
tumour, and
• with the change of its position under
anaesthesia, exacerbates the airway
compression.

50. • Spontaneous ventilation preserves
diaphragmatic movements in a caudal
direction so that a normal transpleural
pressure gradient is maintained.
• keeps the airway dilated and thus minimizes
the airway collapsibility from the extrinsic
compression by the mediastinal mass.

51. • Must work out an appropriate anaesthetic
plan that will avoid the airway obstruction
• Ready with an alternative that will quickly
establish the airway patency or restore the
oxygenation.
• Plan is prepared in consultation with the
surgeon.

52. • Measures during premedication??

53. • Preserving the spontaneous ventilation
during induction of anaesthesia appears to
be an important component.
• Sedative premedication should be avoided in
the symptomatic patients.
• Opoids and benzodiazepines delay the
awakening and are dose dependent
respiratory depressants.

54. • Benzodiazepines also have muscle relaxation
properties
• Exacerbate airway compression by increasing
the tracheobronchial collapsibility by the
large mediastinal masses.
• Atropine or glycopyrrolate are used as
antisialogogue agents.

55. • Optimal anaesthetic management of a
patient with anterior mediastinal mass
• Guided by the presence of symptoms of
airway obstruction,
• Reduction in tracheobronchial lumen
assessed on CT scan,
• Reduction in the flow rates determined by
expiratory plateau of the flow volume study.

56. • Technique for biopsy??

57. • Tissue biopsy should be performed under LA or
regional anaesthesia
• In a symptomatic patient with large mediastinal
mass with definite evidence of airway
obstruction.
• Application of EMLA (eutetic mixture of local
anaesthetics) cream locally, improves the
cooperation
• In a very young symptomatic child for obtaining
superficial lymph node biopsy.

58. • Lymph node / tissue biopsy can be performed
safely
• With the use of ketamine sedation or
anaesthesia.
• Usually antisialogogue agents are used before
administration of ketamine to decrease the
salivation.
• Spontaneous ventilation under ketamine
anaesthesia preserves
• a normal transpleural pressure gradient and so,
airway patency.

59. • Tissue biopsy can also be performed under
general inhalational anaesthesia,
• In high risk patients with severe airway
compression,
• When the procedure cannot be performed
under LA.

60. • Technique for definitive surgery??

61. • The optimal anaesthetic plan for definitive
surgery via sternotomy or thoracotomy
should be decided on the basis of
• airway obstruction, based on symptoms,
• reduction in tracheobroncheal lumen
revealed on CT scan examination,
• severity of expiratory plateau shown on
supine flow volume loop study and abnormal
echocardiography.

62. • If there is no evidence of airway obstruction,
• Inhalational induction with a volatile
anaesthetic agent such as,
• sevoflurane / halothane or titrating dose of
IV propofol or ketamine is preferred.

63. • After documentation of the airway patency by
bag and mask ventilation,
• A short acting muscle relaxant
(suxamethonium) can be used to facilitate
endotracheal intubation.
• If IPPV can be achieved without any problems,
• a long acting muscle relaxant can be
administered, till the procedure is completed.

64. • Ready to deal with any eventuality
• Use of muscle relaxants and positive pressure
ventilation may result in
• Catastrophic airway obstruction, as the
increased gas flow across the stenosis
• Decreases intraluminal pressure leading to
further tendency to collapse.

65. • Patient has evidence of airway obstruction, a
more careful approach is required.
• Obstruction is severe as evidenced by
• Stridor,
• Orthopnoea, supine dysponea,
• Tracheal cross sectional area less than 50% of
the predicted.

66. • PEFR less than 50% of the predicted and
• Supine flow volume loop study shows severe
expiratory plateu.
• Utilize various methods to deal with the obstructed
airway.
• Fibreoptic bronchoscope,
• Rigid bronchoscope,
• emergency tracheostomy set
• Double lumen tubes etc. should be readily available.

67. • Preoperatively, radiotherapy and
chemotherapy used to reduce the tumour
size and its encroachment on the airways,
• To decrease the risk of airway obstruction.
• Cystic aspiration, technique to relieve lower
airway obstruction
• In large cystic anterior mediastinal mass
• Causing severe airway obstruction and SVSC.

68. • Inhalational anaesthetic technique used for
cystic aspiration.
• Definitive surgery performed 2 days later
under GA with the use of muscle relaxants
and IPPV.
• Induce anaesthesia in the position in which
symptoms of airway compression are not
present.
• Right lateral position in a tumour that is
pressing the left main bronchus.

69. • Awake fibreoptic intubation can be performed
under topical anaesthesia
• To advance the tip of the ETT in the non
compressed area before induction of
anaesthesia.
• If awake intubation is not possible, induction
and intubation can be performed under deep
inhalational anaesthesia.
• A short acting muscle relaxant can be
administered with all precautions.

70. • Airway compression of the trachea and distal
main bronchi pose difficult challenge.
• The rigid bronchoscope or endotracheal
intubation cannot be performed beyond the
obstructed segment of the airway.
• Tracheostomy will also not be helpful.

71. • Have some standby measures such as CPB,
• To overcome the fatal complications that may
occur as a result of total airway obstruction.
• Include cannulation of vessels and
• Keeping CPB circuit primed and ready for
instituting emergency CPB.

72. • Management of acute airway obstruction??

73. Management of acute airway
obstruction
• Emergency tracheostomy would not relieve
the airway obstruction.
• First response should be to minimize or
reverse the deleterious effects of GA (IPPV)
and
• Change the patient’s position.

74. • Change of patient’s position :
• Turning the patient lateral, semiprone or
prone position
• May prove life saving under anaesthesia.
• It relieves the refractory airway obstruction
• Some weight of the tumor decreased from
tracheobronchial tree.

75. • Emergency thoracotomy / median
sternotomy
• and tumor debulking: can relieve airway
obstruction under anaesthesia,
• Decrease the extrinsic compression on the
airway by the anterior mediastinal mass.

76. • Splinting the trachea and main bronchus
• With a long endotracheal tube or armoured
tube or
• By passing a rigid bronchoscope through the
affected region up to the level of carina or
bronchus,
• When normal ETT fails to relieve the airway
obstruction.

77. • Double lumen endobronchial tubes can cross
the tracheal obstruction
• Splinting of the main bronchi can maintain
the airway patency by ventilating each lung
independently.
• But paediatric sizes are not available.

78. • Obstruction of the airway, extending to the
main bronchi
• Require a placement of “inverted Y stents”or
“covered stents.”
• bilateral bronchial obstruction is treated by
endobroncheal placement of a conventional
single lumen endobronchial tube.

79. • Femoro-femoral cardiopulmonary bypass
• Restore the oxygenation in the event of
severe life threatening hypoxia.
• Due to severe airway obstruction or by
compression of the pulmonary artery.

80. • Helium-oxygen mixture
• Extreme difficulty in maintaining oxygenation
encountered under spontaneous inhalational
anaesthesia,
• Helium–oxygen mixture can reduce the
resistance to the airflow through the
compressed airway,
• Help in maintaining the oxygenation.
• Helium is not readily available in India.

81. CONCLUSION

82. • Conclusion
• Airway obstruction most common and feared
complication.
• Symptomatic as well as asymptomatic patients
can develop fatal airway obstruction.
• Identified by the presence of the respiratory
symptoms (cough, stridor, orthopnoea, and
positional dyspnoea),
• pulmonary function study (PEFR, pulmonary
flow-volume loops) and by radiological
evaluation, e.g. X-ray chest, CT scan, MRI scan
and by bronchoscopy.

83. • Chemotherapy/ radiotherapy and cystic
aspiration shrink the tumour size and relieve
airway compression.
• Spontaneous ventilation preferred during the
induction of anaesthesia and
• preparedness to restore airway
and oxygenation is the key to success.

84. THANK YOU