L16 - Surgery Trauma / Pneumothorax / Foreign Body / Cancer / Transplant

Question 1

What is a flail chest?

Answer 1

Movement of segment of chest wall.

Question 2

Causes of flail chest?

Answer 2

Significant force diffused over large area of thorax.

If patient has osteoporosis: less force required

Question 3

Describe muscles in chest

Answer 3

Intercostal muscles with fascial attachments.
Includes
- trapezius
- serratus

Question 4

Describe diagnostic methods to detect a flail chest

2 methods and what do they show

Answer 4

CXR

• demonstrate fractured ribs
• hypovolemia may initially mask underlying pulmonary contusion

ABG
- will show severity of hypoventilation created by pulmonary contusion and pain of rib fractures

Question 5

Treatment options for a flail chest

Answer 5

• Patient controlled analgesia
• Oral pain medication
• Indwelling epidural catheter

Question 6

Haemothroax

Answer 6

Collection of blood within pleural cavity.

Question 7

Haemothorax may be a consequence of…

Answer 7

Blunt, penetrating trauma.

Complication of disease.

Question 8

Describe extrapleural injury which may cause haemothorax

Answer 8

Extrapleural Injury

- trauma to chest wall tissues with violation of pleural membrane

Question 9

Sources of significant persistent bleeding which may cause haemothorax

Answer 9

Intercostal and internal mammary arteries.

Question 10

Describe intrapleural injury which may cause haemothorax

Answer 10

Intrapleural injury

- blunt, penetrating injury involving any intrathoracic structure

Question 11

Describe major arterial, venous structures within the thorax that may be involved in intrapleural injury

Answer 11

Aorta 
Brachiocephalic branches 
Pulmonary arteries 
SVC 
Brachiocephalic vein 
IVC 
Azygous vein

Question 12

Haemodynamic response to haemothorax

Answer 12

Heavy blood loss may cause early symptoms of shock:

• tachycardia
• tachypnea
• decrease in pulse pressure

Question 13

Describe physiologic resolution of haemothorax

Answer 13

• Blood entering pleural cavity exposed to motion of diaphragm, lungs and other intra-thoracic structures
• results in some degree of defibrination of blood
• incomplete clotting occurs

Question 14

How might small, asymptomatic haemothorax progress into large and symptomatic bloody pleural effusion

Answer 14

• Lysis of existing clot by pleural enzymes
• increase in protein concentration in pleural fluid
• results in increase in osmotic pressure within pleural cavity
• Transudation of fluid into pleural space

Question 15

Later stages of haemothorax may lead to…

Answer 15

Empyema

Fibrothorax

Question 16

Empyema

Answer 16

• Bacterial contamination of retained haemothorax

- may lead to bacteremia, or septic shock if left untreated

Question 17

Fibrothorax

Answer 17

• Fibrin deposition develops in an organised haemothorax.
• Coats both parietal and visceral pleural surfaces.
• Adhesive process traps the lung in position
• Prevents lung expansion

Question 18

Pneumothorax

Answer 18

Abnormal collection of air in pleural cavity between lung and chest wall

Question 19

Primary spontaneous pnuemothorax

Answer 19

Occurs without an apparent cause in absence of significant lung disease

Question 20

Secondary spontaneous pnuemothorax

Answer 20

Occurs in the presence of existing lung disease

Question 21

Typical symptoms of pneumothorax

Answer 21

• Sudden onset sharp, one sided chest pain.

- Shortness of breath

Question 22

Describe how a tension pneumothorax occurs?

Answer 22

• There’s an area of damaged tissue.
• One way valve formed.
• Amount of air in chest increases.
• Results in tension pneumothorax.

Question 23

Differential diagnosis for pneumothorax

Answer 23

lung bullae

haemothorax

Question 24

Diagnostic method for pneumothorax

Answer 24

CXR, USS, CT

Question 25

Tactile fremitus

Answer 25

Fremitus: vibration transmitted through body

Question 26

What may increased tactile fremitus show?

Answer 26

Ask patient to repeat '99' while examiner feels vibrations. | Tactile fremitus increased over areas of consolidation

Question 27

What may decreased tactile fremitus show?

Answer 27

Decreased in area of pleural effusion / pneumothorax

Question 28

Describe how haemothorax may develop into large bloody pleural effusion?

Answer 28

- blood entering plueral cavity exposed to motion of diaphragm etc. - some degree of defibrination of blood - incomplete clotting occurs - after cessation of bleeding, lysis of osmotic clots by pleural enzymes - RBC lysis leads to increased protein concentration of pleural fluid - causes transduction of fluid into pleural space. - hence small and asymptomatic haemothroax may progress into large pleural effusion

Question 29

Describe dangers of tension pneumothorax

Answer 29

- Pressure build up in pleural space, compressing lung. - Mediastinal shift to opposite side. - Progressive kinking IVC. - VC eventual obstruction. * MEDICAL EMERGENCY*

Question 30

Tension pneumothorax

Answer 30

- injured tissue forms one way valve - volume of nonabsorpable intrapleural air increases - pressure arises within affected hemithorax - pressure increases - ipsilateral lung collapses and causes hypoxia

Question 31

Cardiac tamponade results in:

Answer 31

- accumulation of fluid in pericardial fluid - reduced ventricular filling - subsequent haemodynamic compromise

Question 32

Management of cardiac tamponade

Answer 32

Emergency subxiphoid percutaneous drainage. | - movement of pericardial fluid

Question 33

3 Phases of haemodynamic changes in tamponade

Answer 33

1. Accumulation of pericardial fluid, impairs relaxation and filling of ventricles. 2. Pericardial pressure increases above ventricular filling pressure. 3. Decreases in cardiac output.

Question 34

Beck's triad

Answer 34

- Increased JVP - hypotension - diminished heart sound

Question 35

Pulsus paradox

Answer 35

Normal inspiratory decrease in systemic BP. While listening to heart sounds during inspiration, pulse weakens or may not be palpated with certain heart beats.

Question 36

Subcutaneous emphysema

Answer 36

When gas or air travels under skin

Question 37

Pathophysiology of subcutaneous emphysema

Answer 37

- injury to parietal pleura that allows for passage of air into pleural space and subcutaneous tissues. - air from alveolus spreading into endovascular sheath.

Question 38

Pulmonary contusion

Answer 38

Blunt injury to lungs causing oedema. Hypoxia. Treatment supportive - humidified o2, pain relief, ventilation