Week One - Case One Flashcards

Question

what are risk factors for primary pneumothorax

Answer 1

smoking including cannabis family history Marfan syndrome Homocytinurea Familial Birt-Hogg-Dube syndrome

Answer 2

secondary to underlying disease

Answer 3

autosomal dominant connective tissue disorder mutation of FBN-1 gene, decreased production of extracellular microfibril (maintenance of elastic fibres)

Answer 4

COPD Cystic fibrosis Lung malignancy Pneumonia TB

Answer 5

autosomal dominant mutation in the folliculin gene

Answer 6

air in the pleural space but the volume is not increasing

Answer 7

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

Answer 8

similar to primary However, symptoms are usually more severe in secondary pneumothorax - presumably due to the reduced reparatory reserve seen in underlying ling disease

Answer 9

trachea is not deviated, lung collapse may be visible

Answer 10

LIFE THREATENING air in the pleural space, and the volume continuing to increased

Answer 11

the formation of a one way valve allowing air into the pleural space on inspiration but not out again on expiration

Answer 12

a tracheal deviation away from the side of the pneumothorax

Answer 13

rapidly increased intra-thoracic pressure this reduces venous return to the heart and causes cardiac arrest if not treated quickly

Answer 14

procedure related / barotrauma in ICU

Answer 15

RTC, trauma, fall

Answer 16

pleuritic chest pain Breathlessness Tracheal deviation Reduced breath sounds in the affected area and hyper-resonant on percussion

Answer 17

A tension pneumothorax will have; worsening clinical signs and symptoms (simple will be stable) Tracheal deviation Haemodynamically unstable Hypotensive Tachycardic Elevated respiratory rate

Answer 18

usually a clinical diagnosis - it is a tension pneumothorax

Answer 19

equally visible on inspiratory and expiratory chest X-rays. Standard inspiratory film is all that is usually required.

Answer 20

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.

Answer 21

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

Answer 22

deep sulcus sign

Answer 23

Measure the width of the rim of air to classify to small < or equal to 2cm Large > 2cm

Answer 24

evidence of underlying lung disease on CXR Uncertain diagnosis Not routinely indicated.

Answer 25

Ultrasound

Answer 26

hypoxia Usually normal CO2 - the lung function is still good and often the remaining lung can proceed sufficient alveolar ventilation

Answer 27

if there is sufficient hyperventilation to cause low carbon dioxide

Answer 28

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 to ensure 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 humidified oxygen It is recommended that patient avoid air travel for at least 2 weeks after resolution. The exact risks are not known

Answer 29

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

Answer 30

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

Answer 31

If suspected, attempt to aspirate before CXR. Use a large bore cannula and, if possible with 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 a long 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 in just above the 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.

Answer 32

consider pleurodesis (VATS procedure)

Answer 33

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.

Answer 34

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

Answer 35

changes in pleural pressure

Answer 36

sinus tachycardia