Week One - Case One Flashcards
what is musculoskeletal pain caused by
injury to the muscles or bones that is detected via the pain receptors that carry impulses to the brain
when would musculoskeletal pain occur
after some exertion or injury - exacerbated by movement
would there be any additional features such as coughing blood or fever in musculoskeletal pain
no
what is the most common form of chest pain
musculoskeletal pain
what are some question to ask when querying musculoskeletal pain
Has the patient done any strenuous exertion or exercise recently that may have caused the pain?
Does the pain get worse if the patient twists their upper chest or touch their chest wall?
Has this ever happened before?
what is pleurisy
is an inflammation of the pleura - the two layers
what kind of pain does pleurisy cause
sharp pain due to the innervation of the parietal pleural innervation
what are the most common causes of pleurisy
viral or bacterial infections
what are the symptoms of pleurisy
cough, runny nose and fever
what is absent in pleurisy
Haemoptysis
what are questions to ask when querying pleurisy
Has the patient had a recent cough, cold or viral infection?
Has the patient had a recent fever?
Is there a cough? Is it productive?
Has this ever happened before?
what is a pneumothorax
the presence of abnormal air between the two pleural linings called the pleural space
how does this air leak cause lung collapse
this air leak builds up, thus stretching the pleural lining and presses on the lung to cause it to collapse
what are the symptoms of a pneumothorax
sharp chest pain and breathlessness
what are risk factors for pneumothorax
underlying lung disease, being male, smoking
what are questions to ask if querying a pneumothorax
Does the patient’s gender and age fit with those in the population most at risk?
Does the patient smoke?
Has this ever happened before?
what is a pulmonary embolism
is an abnormal clot formation in the pulmonary circulation to the lung that results in reduced blood flow to the region of the lung that the pulmonary artery supplies
this causes infection of the lung
what are the symptoms of PE
breathlessness
pleuritic chest pain
sometimes Haemoptysis
can there be calf swelling with PE
yes
what are the questions to ask about when querying a PE
Does the patient have any risk factors for PE?
Is there any coughing of blood?
Has the patient noticed any calf swelling?
Has this ever happened before?
what is a primary spontaneous pneumothorax
no underlying disease
usually the result of rupture of a pleural ‘bleb’ - congenital defect in the tissue of the alveolar wall
who is a primary spontaneous pneumothorax most common in
most common in tall young men
what is homocystinurea
body can’t process the amino avid methionine
what is the recurrence rate
25-50%
what are risk factors for primary pneumothorax
smoking including cannabis
family history
Marfan syndrome
Homocytinurea
Familial Birt-Hogg-Dube syndrome
what is a secondary pneumothorax
secondary to underlying disease
what is Marfan syndrome
autosomal dominant connective tissue disorder
mutation of FBN-1 gene, decreased production of extracellular microfibril (maintenance of elastic fibres)
what may these underlying diseases be
COPD
Cystic fibrosis
Lung malignancy
Pneumonia
TB
what is familial Birt-Hogg-Dube syndrome
autosomal dominant mutation in the folliculin gene
what is a standard or simple pneumothorax
air in the pleural space but the volume is not increasing
what is the presentation of a primary pneumothorax
symptoms develop at rest
Sudden onset SOB and pleuritic chest pain
Reduced breath sounds on affected side
Hyperressonance to percussion on the affected side
Hypoxia
what is the presentation of a secondary pneumothorax
similar to primary
However, symptoms are usually more severe in secondary pneumothorax - presumably due to the reduced reparatory reserve seen in underlying ling disease
what does a simple pneumothorax look like on a CXR
trachea is not deviated, lung collapse may be visible
what is a tension pneumothorax
LIFE THREATENING
air in the pleural space, and the volume continuing to increased
what is a tension pneumothorax due to
the formation of a one way valve allowing air into the pleural space on inspiration but not out again on expiration
what is visible on a CXR in a tension pneumothorax
a tracheal deviation away from the side of the pneumothorax
what does a tension pneumothorax cause
rapidly increased intra-thoracic pressure
this reduces venous return to the heart and causes cardiac arrest if not treated quickly
what is a Iatrogenic Pneumothorax
procedure related / barotrauma in ICU
what is a non-iatrogenic pneumothorax
RTC, trauma, fall
what are the clinical features of a tension pneumothorax
pleuritic chest pain
Breathlessness
Tracheal deviation
Reduced breath sounds in the affected area and hyper-resonant on percussion
how do you differentiate between a simple and tension pneumothorax
A tension pneumothorax will have;
worsening clinical signs and symptoms (simple will be stable)
Tracheal deviation
Haemodynamically unstable
Hypotensive
Tachycardic
Elevated respiratory rate
what is the investigations in pneumothorax
usually a clinical diagnosis - it is a tension pneumothorax
what kind of CXR is taken
equally visible on inspiratory and expiratory chest X-rays. Standard inspiratory film is all that is usually required.
what is the presentation of a small pneumothorax on a CXR
Typically small and often appear as a rim of air around the lung. It is often possible to see a white line which represented the edge of the normal lung tissue.
Externally to this, there will be NO vascular lung markings.
what is the presentation of a large pneumothorax on a CXR
larger pneumothoraxes are more obvious, with a clearly collapsed lung and a large proportion of the hemithorax with no vascular margins
Check for mediastinal shift - tension pneumothorax
what is seen on a supine CXR
deep sulcus sign
what are the measurements used to classify small/large
Measure the width of the rim of air to classify to
small < or equal to 2cm
Large > 2cm
what are the indications for a CT
evidence of underlying lung disease on CXR
Uncertain diagnosis
Not routinely indicated.
what is not routine for a pneumothorax but becoming more common in the acute setting
Ultrasound
what shows on a ABG
hypoxia
Usually normal CO2 - the lung function is still good and often the remaining lung can proceed sufficient alveolar ventilation
when can respiratory alkalosis occur
if there is sufficient hyperventilation to cause low carbon dioxide
what is the treatment for a standard pneumothorax <2cm
should do CXR first before attempting to treat!
Rim of air <2cm – consider alternate diagnosis, OR small pneumothorax that will resolve with conservative management.
Consider observation for 4-6 hours and repeat CXR toensure it is not progressing
Then; discharge on advice – dont do strenuous exercise – and return if breathless.
Evaluate and re-x-ray at 2 weekly intervals until air is re-absorped
The rate of reabsorption is approximately 1-2% of the volume of the hemithroax per 24 hours. This can be increased to 6-8th with the use of humidifiedoxygen
It isrecommended that patient avoid air travel for at least 2 weeks after resolution. The exact risks are not known
what is the treatment for a primary pneumothorax
SOB + rim of air >2cm on CXR:
Give supplemental oxygen
If acutely unwell (i.e. haemdynamically unstable), or tension pneumothorax:
Attempt aspiration – 2ND INTERCOSTAL SPACE, MIDCLAVICULAR LINE!
If unsuccessful, repeat
If unsuccessful, consider chest drain
Once successfully decompressed, will need a chest drain to allow continuing decompression
If not haemodynamically unstable:
Chest Drain (can be traditional thoracotomy or ‘pig-tail’ catheter (becoming more common – same equipment used as in supra-pubic catheter – therefore involves seldinger technique, is a less invasive procedure)
Remember to connect the chest tube to a water seal device – and check that the water ‘swings’ (rises and falls) with each breath – this confirms correct placement of the tubs within the pleural space
Refer to ICU if appropriate and admit to hospital
what is the treatment for secondary pneumothorax
SOB + rim of air >2cm on CXR:
As above
Treat any underlying cause as appropriate
More likely to be hospitalised – because more likely to be unwell, and also because they may need treatment of the underlying condition and / more likely to require a pleurodesis
what’s the treatment for a tension pneumothorax
If suspected, attempt to aspirate before CXR. Use a large bore cannula and, if possiblewith syringe, filled with saline, to act as a water seal, when entering the pleural space.
You should attempt decompression at the 2nd intercostal space at the mid-clavicular line. Feeling for this is sometimes a bit tricky – it is roughly 2 finger widths below the clavicle
Use along needle –preferable a cannula about 8cm or longer. Needle decompression fails in up to 50% of patients – often because too short of a needle is used. The typical distance from skin to pleura in an adult male is about 5cm
You should go injust abovethe third rib, so as to avoid the neurovasuclar bundle below the second rib.
Needle decompression is only a temporary measure –a chest tube should be placed as soon as possible. In a non-tension pneumothorax a chest drain is often the first line treatment of choice.
Needle decompression is suprisingly ineffective – one study suggested it was only about 67% effective at decompression, compared to over 90% for the placement of a chest tube. As such, a chest tube is preferred if circumstances allow, however it takes longer (mainly getting set up with all equipment . scrubbing up etc). If you are in doubt, do a needle aspiration first (you might save the patient’s life) and follow-up with a chest drain.
what happens if a pneumothorax remains at 48 hours or recurrent episodes
consider pleurodesis (VATS procedure)
what is the pathophysiology of a pneumothorax
In a healthy lung:
lungs tend to collapse due to elastic recoil
Connective tissue fibres (elastin)
Surface tension forces at the air/liquid interface in the alveolus
the chest wall tends to expand
The tendency for elastic recoil to collapse lungs and chest wall to expand means pleural pressure with be negative compared to alveolar pressure
when no muscles act on the chest wall, ‘equilibrium’ will be achieved, when the force generated by the pressure gradient across the alveolar wall (trans-pleural pressure: Pleural pressure (Ppl) - alveolar pressure(Palv) ) is equal and opposite to elastic recoil
Equilibrium is known as the Functional Residual Capacity. Lungs will sit at FRC at the end of every normal expiration, when respiratory muscles are relaxed.
at FRC what are the pressures present?
Alveolar pressure equals atmospheric pressure therefore there is no airflow
for inspiration;
Alveolar pressure must be less than atmospheric pressure
for expiration;
Alveolar pressure must be greater than atmospheric pressure
what are changes in alveolar pressure a result of
changes in pleural pressure
what is the most common ECG abnormality
sinus tachycardia
