SVC Obstruction DDx

  • Obstruction of the superior vena cava results from mediastinal mass lesions.
  • Features include a plethoric and cyanosed face with periorbital oedema, exophthalmos, conjunctival injection, and venous dilatation in the fundi, distended non-pulsatile neck veins and a positive Pemberton sign.

Causes

  • lung cancer (90%)
  • retrosternal tumours e.g. lymphoma, thymoma, dermoid
  • retrosternal goitre
  • massive mediastinal lymphadenopathy
  •  aortic aneurysm

OVERVIEW

  • impaired venous return through the SVC to the RA
  • SVC = principle venous drainage to head, neck and upper extremities
  • major collateral = azygous vein which joins SVC posteriorly over the right main bronchus and drains the posterior thorax.
  • if obstruction distal to azygous -> body can cope
  • if obstruction proximal to azygous -> flow must bypass the SVC and return via the internal mammary, superficial thoracoabdominal, vertebral venous system -> IVC -> resulting in very high pressures

HISTORY

  • SOB
  • oedema to face, neck, upper torso, upper limbs
  • cough
  • hoarseness
  • syncope
  • headaches
  • chest pain
  • dysphagia

RISK FACTORS

  • bronchogenic carcinoma
  • lymphoma
  • breast cancer
  • other malignancies
  • indwelling catheters
  • granulomatous disease

EXAMINATION

  • JVP distension (non-pulsatile)
  • oedema of face or upper extremities
  • dilated venous collaterals
  • plethora
  • tachypnoea
  • exopthalmos
  • conjunctival injection
  • Pemberton’s sign
  • papilloedema
  • stridor
  • Horners syndrome
  • cardiac tamponade
  • pleural effusions
  • hoarse voice
  • phrenic nerve paralysis -> high hemidiaphragm

INVESTIGATIONS

  • CXR: masses
  • HRCT: thoracic neoplasm, retrosternal thyroid, mediastinal fibrosis, thrombosis from intravascular device, aneurysm
  • bronchoscopy:
  • TTE:
  • mediastinoscopy + biopsy
  • MRI: masses
  • node biopsy
  • sputum cytology
  • bone marrow aspiration

MANAGEMENT

Goals

(1) diagnose cause
(2) treat obstruction
(3) supportive care

  • determined by aetiology
  •  early consultation (oncology, radiation oncology, cardiothoracics)
  •  steroids
  • chemotherapy
  • radiotherapy (30 Gr in 10 fractions)
  • thrombolytics in thrombotic cases -> stent -> anticoagulation
  • surgical resection and reconstruction
  • IV access in IVC territory
  • prepare for:

-> cardiovascular collapse (tamponade)
-> central airway obstruction
-> laryngeal dysfunction
-> associated respiratory failure

  • may respond to adopting the prone position

CCC 700 6

Critical Care

Compendium

Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also the Innovation Lead for the Australian Centre for Health Innovation at Alfred Health and Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of two amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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