pleural and chest wall disease Flashcards
what happens during inhalation
scalene muscles elevate 1st and 2nd ribs
inferior part of sternum moves anteriorly
external intercostal muscles elevate ribs
diaphragm moves inferiorly during contraction
what can result in altered respiratory mechanics
Chest wall (kyphoscoliosis) Respiratory muscle weakness
what are the types of pleura
visceral and parietal
costal, mediastinal, costomediastinal
what does the pleura do
Thin tissue covered by a layer of cells (mesothelial) that surrounds the lungs and lines the inside of the chest wall
Two sides are completely separate
Pleural space is normally at negative (subatmospheric) pressure (keep lungs inflated)
what is pleural fluid
Normal pleural space has only a few mls of fluid (lubricate lungs in normal breathing)
Pleura is 0.3-0.5 mm thick
Pleural fluid forms <1mm film
Fluid contains protein and small numbers of cells
Lymphocytes, macrophages, mesothelial cells
pH. 7.6
what happens if fluid or air moves into the pleural space
effusion or pneumothorax
accumulation of positive pressure – lung collapse
what are common pleural conditions
pneumothorax pleural effusion pleural infection/empyema malignant pleural effusion heart failure haemothorax
how do pleural conditions present
breathlessness
chest pain
cough
features in history
raised respiratory rate, may have low oxygen sats
if unwell with tension pneumothorax – may be very unwell/peri arrest
on examination: reduced breath sounds, increased percussion note, reduced expansion, tracheal deviation
abnormal CXR
what is a pneumothorax
air in pleural space
entry of air – positive pressure – lung collapse
tension pneumothorax – one way valve
primary/secondary/traumatic/iatrogenic (caused by treatment)
how do primary spontaneous pneumothorax’s occur
Occurs in healthy young tall males Apical bleb More common in smokers (esp cannabis) Tension rarely occurs Managed according to size and symptoms – won’t always need a drain or admission
how do secondary pneumothorax’s occur
Background of known lung disease eg COPD, bronchiectasis, ILD etc
Mostly will need drain
Tension more common
how are primary and secondary pneumothorax’s followed up
Primary
54% recurrence in first 4 years
20-30% recurrence in first 2 years – cont smoking
Recurrent primary – surgical/medical thoracoscopy and pleurodesis
Secondary
Attempt pleurodesis after the first episode as recurrence rate is high
what is advised post pneumothorax
No deep sea diving ever (sudden change in pressure risk)
Normal swimming and diving to less than 10 feet depth is fine
Air travel – one week after full re-expansion
Coast guards, naval officers, air force will need to change jobs
High altitude sports and travel should be done with caution/discouraged
Stop smoking
what is a pleural effusion
Small vol of lubricating fluid is maintained via a delicate balance of hydrostatic and oncotic pressure, and lymphatic drainage
Disturbances in any of these mechanisms can cause pleural effusion
what are the clinical features of pleural effusion
SOB, cough, pleuritic chest pain, reduced breath sounds, dull to percuss
what are the causes of pleural effusion
Acute vs chronic, benign vs malignant
Altered permeability of pleural membranes eg infection, inflammation, cancer
Reduced oncotic pressure (low albumin) eg renal disease, liver cirrhosis
Increased capillary hydrostatic pressure ef HF
Decreased lymphatic drainage or blockage eg malignancy, trauma
Increased peritoneal fluid eg liver cirrhosis, peritoneal dialysis
what are the commonest causes of pleural effusion
HF, pneumonia and malignancy
what are some infections that can cause pleural effusions
bacterial, TB, fungal, viral
what are some benign causes of pleural effusion
high oncotic pressure (HF, fluid overload), low protein state (nephrotic syndrome, protein losing enteropathy, chronic liver disease), AI (rheumatoid arthritis, SLE), reactive (PE, dresslers syndrome)
what are some malignant causes of pleural effusion
primary (mesothelioma), secondary (most common – primary lung, breast, gynaecological, haematological, renal, GI tract)
what is pleural infection
Common – many due to pneumonia (high risk, increased mortality)
Prolonged hospital admission
what are risk factors for pleural infection
Diabetes Immunosuppression (steroids) Alcohol, IVDU Poor oral hygiene and aspiration (anaerobic) Iatrogenic eg previous pleural procedure Trauma Recent hospitalisation
how is pleural infection diagnosed
Pleural effusion seen on CXR with systemic features of infection such as fever, raised CRP/WCC suggest infection
Take pleural fluid sample
Predictors of worst outcome – pH <7.2 high LDH, low glucose (<2/3 of serum glucose), positive culture, loculations (seen on ultrasound or CT)
what is the spectrum of parapneumonic effusions
Uncomplicated – resolve on treatment of underlying pneumonia, may not need to be drained
Complicated – bacterial invasion into pleural space, fibrin deposition may form locules/septations, patients will likely need a drain
Empyema – frank pus in pleural cavity, may organise with thickening of pleural surface preventing lung re expansion and impairing function
what are the principles of care for pleural effusions/infections
Accurate diagnosis
Control infection – choose correct antibiotics
Drainage of infected material – chest drain, U/S, consent, safe to do so
Management of chest drain key – remove infection from pleural space so avoid blockages
what is malignant effusion
High recurrence rate
Median life expectancy for malignant effusion of any cause – 6 months
Significant impact on quality of life – last few weeks of life
Impact on wider health economy – average LOS 4 to 6 days
what is a malignancy effusion
Mostly unilateral
Massive are not usually benign
SOB, cough, hypoxia, mostly they are haemorrhagic
how are malignancy effusions managed
Minimally invasive and reduced umber of interventions
Options available
Aspiration >90% recurrence rate, chest drain (+ pleurodesis 60-70% success)
Indwelling pleural catheter
Thoracoscopic drainage + pleurodesis
why could drainage by an indwelling pleural catheter be used for ME
Avoid patient admission to hospital
Suitable for long term drainage
Improve quality of life
50% spontaneous pleurodesis
how can talc pleurodesis (without infection) be used for ME
To prevent recurrence
Medicated talc
Created talc slurry to stick pleural together
Works in about 70%
Lung needs to be reinflated, output <200 ml/24 hr
Drain can’t be blocked or fall out
Pain/fever
What is a harm-thorax
Not bloody effusion (hct >50%)
Traumatic, iatrogenic, Aortic dissection
Depending on cause
Resuscitate, urgent drainage (surgical drain), consider VATS pleurodesis and medical thoracoscopy
