Pleural Malignancy and Disease Flashcards
describe pleural anatomy
serous membranes
the visceral pleura covers the lungs and forms interlobar fissures
the parietal pleura covers the mediastinum, diaphragm, and inner surface of the thorax
inferior margins of the pleura considerably lower than the corresponding border of the lung
usually contains approx 4mls (depending on weight)
need approx 200ml x fluid to be detected on plain chest x-ray
lubricates the 2 pleural surfaces
allowing the pleura to slide smoothly during respiration
surface tension allows lung surface to stay touching thoracic wall, creating a seal between 2 surfaces
2 layers combine around the hila of the lung - so the hila have no pleural coverage
the pleural layers combine to form the pulmonary ligament, which runs inferiorly and attached the root of the lung to the diaphragm
describe pleural effusion
abnormal collection of fluid in pleural space
common presentation of numerous diseases
does not always require drainage or sampling (e.g. cardiac failure)
large unilateral effusions should raise concern
describe the workup of pleural effusion
PA chest x-ray
pleural aspirate (if not convincingly cardiac failure)
biochemistry;
transudate - protein <30 g/l, does not always have a benign aetiology
exudate - protein>30 g/l, always look for serious pathology (malignancy, infection (TB), pulmonary infarct, asbestos)
cytology
culture
other tests - contrast enhanced CT chest, repeat pleural tap, pleural biopsy (blind or thoracoscopy)
describe pleural fluid appearance
straw-coloured e.g. cardiac failure, hypoalbuminaemia
bloody e.g. trauma, malignancy, infection, infarction
turbid/milky e.g. empyema, chylothorax
foul smelling - anaeoribc empyema
food particles - oesophageal rupture
bilateral - LVF, PTE, drugs, systemic path
describe the biochemistry of pleural effusion
fluid pH;
<7.3 = pleural inflammation (malignancy)
<7.2 = requires drainage in the setting of infection
glucose;
low in infection, TB, rheumatoid arthritis, malignancy, oesophageal rupture, SLE
describe cytology and cell counts
mostly looking for malignant cells (2 samples will dx up to 2/3 malignant effusions)
lymphocytes - think TB, malignancy, although any long standing effusion will eventually become lymphocytic
neutrophils suggest acute process
describe the microbiology
gram stain and microscopy
culture
PCR, AFB stain and liquid culture
put in blood culture bottle for higher yield
describe pleural tap
total pleural protein - 43 g/l
pleural LDH 240 iu/l
culture - no growth of pathogenic bacteria
this is a cellular sample consisting entirely of macrophages and degenerate mesothelial cells
no evidence of malignancy is seen
describe thoracentesis
removes excess fluid, pleural effusion, from pleural space
pleural aspiration will diagnose malignancy in approximately 60% of patients with malignant pleural effusion
a second sample may increase the yield slightly, third and subsequent samples are non-contributory
increasing the volume of aspirate does not increase yield
pleural fluid cytology has an even poorer diagnostic yield in mesothelioma in which a positive result in obtained in less than a third of cases
describe tissue biopsies
blind percutaneous pleural biopsy - abrams
image (CT) guided cutting needle pleural biopsy
thoracoscopy
thoracotomy
describe ancillary effusions
systemic tumour effects - embolism, hypoalbuminaemia
local tumour effects - post obstructive infection, lymphatic obstruction, atelectasis
describe mesothelioma
uncommon malignant tumour of the lining of the lung or very occasionally of the lining of the abdominal cavity
likelihood of developing mesothelioma increases with the degree and the length of time exposed to asbestos
occasionally may occur in people who have not worked with asbestos but have been associated with people who have
takes 30-40 years to develop
may cause breathlessness, chest pain, weight loss, fever, sweating, cough
describe asbestos
chrysotile - white, most common
amosite - brown
crocidolite - most dangerous
describe investigations of mesothelioma
imaging - pleural nodularity, circumferential pleural thickening, local invasion, lung entrapment
pleural fluid aspiration - low cytological yield, avoif repeated aspiration
biopsy - thorascopy or CT/US guided
describe treatment of mesothelioma
pleurodese effusions radiotherapy surgery chemotherapy palliative care report deaths to fiscal
describe malignant pelural effusions
virtually all cancers may metastasize to the plerua especially; lung cancer breast cancer upper GI, lymphoma, melanoma, ovary median survival 3-12, large variation
describe the treatment for malignant pleural effusion
nothing, palliate symptoms repeated pleural taps drain and/or pleurodesis (talc slurry or during thoracoscopy) long term pleural catheters surgical options (abrasion, pleurectomy)
describe talc
sclerosing agent - irritates lining of chest cavity, causing cavity to close as there is no space or fluid
complications; minor pleuritic pain and fever pneumonia (rare) respiratory failure (rare) talc pneumonitis/ARDS (rare) secondary empyema (rare) local tumour implantation at port sight mesothelioma
treatment - poudrage/insufflation (thoracoscopic instillation)
describe long term pleural catheters
designed to allow patients control their effusion and therefore symptoms
inserted mostly in patients with malignant effusions
drain is designed to remain in place for life though some people will stop producing pleural fluid (never drain more than 1 litre a day)
complications - incorrect placement, bleeding, infection (patients still able to shower, bath and swim)
describe survival time for malignant pleural effusion
LENT score; LDH ECOG PS (serum) neutrophil to lymphocyte ratio tumour type
describe primary and secondary pneumothorax
primary;
normal lungs
apical bullae rupture
secondary;
underlying lung disease (COPD)
describe the presentation of pneumothorax
primary spontaneous - asymptomatic even if moderately sized
secondary spontaneous - symptomatic even if small
acute onset pleuritic chest pain SOB, hypoxia signs; tachycardia hyper-resonant percussion note reduced expansion quiet breath sounds on auscultation Hamman's sign
describe the management of pneumothorax
oxygen even if no drain no treatment if asymptomatic and small aspiration 1st line in PSP; avoids chest drain time consuming may fail especially if age>50 or SSP chest drain may need suction surgical intervention
describe tension pneumothorax
emergency - can lead to cardiac arrest
one way valve, progressively increasing pressure in pleural space
pushes other chest organs to opposite side to affected side
acute respiratory distress
signs - trachea deviated to opposite side, hypotension, raised JVP, reduced air entry on affected side
ventilated patient (invasive or not) CPR esp PEA blocked, kinked, misplaced drain pre existing airways disease patients undergoing hyperbaric treatment
describe treatment of tension pneumothorax
needle decompression;
usually with large bore venflon
second intercostal space anteriorly, mid-clavicular line
describe pleural infection
increasing incidence esp extremes of age
significant mortality
does not always follow pneumonia
can rapidly coagulate and organise to form fibrous peels even with antibiotics
do not let the sun set on a potentially infected pleural space
simple parapneumonic effusion
compicated parapneumonic effusion
empyema (pus)
-quickly sample pleural fluid to identify effusion that require urgent tube drainage
describe the risk factors of pleural infection
diabeteres mellitus immunosuppression including corticosteroids gastro-oesophageal reflux alchol misuse intravenous drug abuse *may have no apparent risk factors*
describe pleural infection - different types of effusion
complicated effusion; \+ve G stain pH <7.2 low glucose spetations locualtions
simple effusion;
none of the above may be treated with antibiotics alone but may need drainage later on if things change
large effusion - chest drainage
small effusions may be left untapped
describe management of pleural infection
antibiotics drain effusion as needed early discussion with surgeon if persistent sepsis nutrition VTE prophylaxis role for fibrinolytics/Dnase
