Respiratory emergencies QUIZ Wk10

Question 1

3 types of pneumothorax

Answer 1

Closed, open, tension(needle decompression)

Question 2

What is a pleural effusion

Answer 2

Abnormal accumulation of fluid in pleural cavity

Question 3

Types of pleural effusion

Answer 3

Transudative pleural effusion
Exudative pleural effusion
Hemothorax

Question 4

What is transudative pleural effusion caused by

Answer 4

Cardiac failure
Hypoalbuminemia eg nephrotic syndrome. liver disease, protein malnutrition

Question 5

Etiology of pleural effusion (traumatic)

Answer 5

 Blunt trauma
 Penetrating trauma (including iatrogenic)

Question 6

Etiology of pleural effusion (non-traumatic/spontaneous)

Answer 6

 Neoplasia (primary or metastatic)
 Blood dyscrasias, including complications of anticoagulation
 Pulmonary embolism with infarction
 Torn pleural adhesions in association with spontaneous pneumothorax

Question 7

Pathophysio of pleural effusions

Answer 7

Small effusions – no symptoms
 Minimum of 300 ml in the pleural cavity to be seen in the x-rays (costophrenic angle)

Large effusions
 Interferes with lung expansion with
reduction in vital capacity
 Hypoxia and hypercapnia

Question 8

Clinical features of hemothorax

Answer 8

Acute pleural pain, dyspnea

Small effusions
 No findings or shifting dullness on percussion

Large effusions
 Decreased chest movements
 Shift of mediastinum structures
 Dullness on percussion breath sounds

Question 9

Treatment of hemothorax

Answer 9

If a hemothorax is equal to or greater than the
amount required to obscure the costophrenic
sulcus or is found in association with a pneumothorax based on chest radiograph findings, it should be drained by tube thoracostomy

Question 10

What is pneumothorax

Answer 10

 Collection of air in pleural cavity

Question 10

When should surgical exploration in cases of traumatic hemothorax be performed

Answer 10

 Greater than 1000 mL of blood is evacuated immediately after tube thoracostomy. This is
considered a massive hemothorax.
 Bleeding from the chest continues, defined as 150-200 mL/h for 2-4 hours.
 Persistent blood transfusion is required to maintain hemodynamic stability

Question 11

Types of pneumothorax

Answer 11

spontaneous / chest trauma

Question 12

cause of Spontaneous pneumothorax

Answer 12

 Rupture of bulla(e) on surface of lungs
 Bronchial asthma, COPD, tuberculosis

Question 13

why chest trauma results in pneumothorax

Answer 13

 Negative pleural pressure will allow air to enter

Question 14

Clinical features of pneumothorax

Answer 14

Acute pleural pain, dyspnea in large pneumothorax
 Decreased chest movements
 Shift of mediastinal structures
 Hyper-resonance on percussion and absent breath sounds

Question 15

Tension pneumothorax arises from progressive _____ of a simple ______

Answer 15

 Arises from progressive worsening of a simple pneumothorax

Question 16

Tension pneumothorax is associated with formation of a _______ at point of _____ in the lung

Answer 16

Associated with formation of a one-way valve at point of rupture in the lung

Question 17

In tension pneumo, air becomes ___ in ______ and builds up which:

Answer 17

 Air becomes trapped in pleural cavity and builds up -> Prevents lung from inflating fully

Question 18

What is tension pneumo?

Answer 18

Tension pneumothorax: The accumulation of
air under pressure in the pleural space.

The air enters the pleural cavity and is trapped there during expiration so the air pressure within the thorax mounts higher than atmospheric pressure, compresses the lung,
may displace the mediastinum and its
structures (including the lung) toward the opposite side, and cause cardiopulmonary impairment (decrease cardiac output)

Question 19

Tension pneumo causes collapse of ___ and shift of ___ structures

Answer 19

Causes collapse of lung and shift of mediastinal structures

**CVS collapse due to poor VR (venous return)

Question 20

Complications of pneumothorax

Answer 20

 Venous return and cardiac output decrease with
hypotension and tachycardia
 Hypoxemia due to alveolar collapse
 Reexpansion pulmonary edema
 Bronchopleural fistula - Bronchopleural fistula (BPF)
is a sinus tract between the main stem, lobar, or segmental bronchus and the pleural space

Question 21

Diagnosis of pneumothorax

Answer 21

• Chest radiography
  – Requires good quality film
  – In ICU, 30% of pneumothoraces are missed due to:
• Low-quality film
• Supine position of patient on AP film
• Air hidden behind thoracic or mediastinal structures
   Radiographic appearance
   Mediastinal shift, diaphragmatic depression, flattened ribs

CT scan - used to confirm size and presence of pneumothorax.

Question 22

What is reexpansion pulmonary edema?

Answer 22

Occurs following rapid lung reexpansion particularly:
 From low lung volumes
 Long duration pneumothorax
 High pressure gradient across lung

May be related to reperfusion injury

Lung reexpansion should be slow
* First, just waterseal, no suction
* If lung fails to reexpand, then apply suction

Question 23

Medical mgmt of pneumothorax

Answer 23

1. Oxygen
   – Should be administered to all patients
   – Supplemental O2 speeds absorption of air from pleural space
2. Observation of stable patients
   – Primary: observe 4 hours, if no enlargement: home
   – Secondary and iatrogenic: hospitalize and observe carefully,
   * If there is any deterioration (SpO2, RR, etc) - drain
3. Simple aspiration
   – Small catheter placed in pleural space
   – Connect to three-way stopcock
   – Slowly evacuate until no more air can be removed
   – This works as many leaks heal between time of leak and its
   drainage.
   – If 4 L air is removed without resistance, chest tube placement is
   required
4. Chest tubes
   – Resolution is mostly determined by lung healing
   – Small bore: placed via small incision in second intercostal space
   (ICS), midclavicular line or laterally, fifth–seventh ICS
   * Connected to underwater seal or Heimlich valve
   – Large bore: placed via blunt dissection, usually connected to
   “three-bottle” chest drainage system
   – Chest tubes are sutured in place
5. Pleurodesis
   – consider with recurrent
   pneumothoraces

Question 24

When is chest tube placement required in pneumothorax?

Answer 24

– If 4 L air is removed (thru simple aspiration) without resistance, chest tube placement is required

Question 25

What is pulmonary edema?

Answer 25

 Life threatening emergency in which excess fluid accumulates in lungs  Characterized by extreme breathlessness  Due to alteration of capillary forces in the alveolar wall

Question 26

Causes of pulmonary edema

Answer 26

Increased Venous hydrostatic pressure  LVF (most common cause) Decreased Plasma osmotic pressure  Hypoalbuminemia Altered alveolar capillary membrane permeability  Acute respiratory distress syndrome (ARDS)

Question 27

Pathophysio of pul edema

Answer 27

Increased pulm capillary pressure  Engorged vessels, lungs less compliant  Increased resistance of small airways (Tachypnoea, wheezing) If pressure ↑ > 25mmHg (normal 15)  Increased filtration of fluid into interstitial space , causing interstitial edema  Gas exchange worsens  Xray changes –Kerley B lines Accumulation of fluid disrupts intercellular membranes  Leads to collection of fluid in alveolar spaces  Alveolar edema

Question 28

Clinical features of pul edema

Answer 28

 Anxiety, profuse perspiration  Acutely breathless  Tachypnea, tachycardia  Wheezing, crepitations  Cough - Productive of frothy, blood-tinged sputum - Can be copious

Question 29

What is PULMONARY EMBOLISM

Answer 29

 Blockage and obstruction of a pulmonary vessel by a blood-borne substance  Common cause of unexpected death  Often missed as symptoms are often non-specific

Question 30

causes of pul embolism

Answer 30

 Thrombus (most common)  Air  Fat  Amniotic fluid  Parasites  Septic emboli  Tumor (renal cell Ca with secondaries to ivc)

Question 31

Risk factors of pul embolism

Answer 31

Virchow’s Triad 1. Venous stasis  Prolonged bed rest  Immobilization  Low CO  Pregnancy 2. Hypercoagulability  Tissue injury after surgery, trauma  Malignancy 3. Vessel wall inflammation

Question 32

Pathophysio of pul embolism

Answer 32

 Normally, microthrombi form and are removed continuously in venous system  Pulmonary vessels act as filters (Remove small emboli from reaching arterial system)  Large clots can damage lung/heart function  > 95% arise from thrombi in deep veins of LL Hemodynamic changes  Obstruction causes ↑ in pulmonary P  RV strain if embolus is large or pre-existing heart disease -> Decreased CO  Large embolus occludes pulmonary bld flow -> No CO -> Sudden death Change in V/Q ratio  Perfusion distal to obstruction ↓ -> Results in compensatory hyperventilation initially Eventually, hypoxemia causes ischemic damage to alveolus  Alveolar collapse -> Pulmonary edema -> ↓ surfactant -> Release of inflammatory chemicals Pulmonary infarction  Occurs in 10% of cases

Question 33

Clinical features of pul embolism (SMALL emboli)

Answer 33

 effort dyspnoea  tiredness  syncope  cardiac arrhythmias

Question 34

Clinical features of pul embolism (MASSIVE emboli)

Answer 34

 Sudden severe central chest pain  Marked tachypnea, dyspnea  Shock

Question 35

Clinical features of pul embolism (in general)

Answer 35

Classic triad of sudden onset of  Dyspnea, pleuritic pain, hemoptysis  20% of patients Swollen, tender, warm calf Auscultation  Inspiratory crackles  Pleural rub  Wheezing ECG  Sinus tachycardia  S1Q3T3 - Deep S in lead I, Q wave, inverted T in lead III

Question 36

The percussion of chest of chest on the patient would reveal a dull percussion. What would be your impression if the dull percussion note changes to hyper-resonant percussion?

Answer 36

Tension pneumothorax Dull percussion: usually due to presence of fluid (hemothorax) In normal lungs: expected percussion note should be resonant In simple pneumothorax: Percussion note will also be resonant In larger pneumothorax (e.g. tension pneumothorax): Percussion note will progress to hyper-resonant

Question 37

What is the best initial test in the diagnosis of hemothorax? a. CXR b. Chest ultrasound c. CT scan d. CT angiography

Answer 37

CXR

Question 38

What is the definitive test in diagnosing hemothorax? a. Chest CT scan b. CXR c. Chest ultrasound d. MRI

Answer 38

Chest CT scan

Question 39

What are the causes of spontaneous hemothorax? a. RTA b. An accidental knick during a CTVS surgery c. metastasis to the pleura d. Pulmonary embolism

Answer 39

Metastasis to the pleura

Question 40

Which of the following are potential life-threatening complications that can occur in massive haemothorax if the blood is allowed to retain in the pleural space? a. Hemopneumothorax and obstructive shock b. Septic shock and lung atelectasis c. Cardiogenic shock and cardiac failure d. Mediastinal spread and septic shock

Answer 40

Septic shock and lung atelectasis

Question 41

What should you do to avoid damaging the neurovascular bundle (Intercostal vein, artery and nerve (in this order)) during insertion of the chest tube? a. Avoid the upper border of the rib while inserting the chest tube b. Avoid the lower border of the rib while inserting the chest tube c. Local anesthesia will prevent injury to the neurovascular bundle d. Inserting the tube in the anterior axillary line will avoid any neurovascular damage.

Answer 41

Avoid the lower border of the rib while inserting the chest tube

Question 42

Which of the following treatment options is suitable if the chest tube drainage shows clear fluid instead of blood like substance and the drainage amount continues to increase? a. Pleurodesis b. Thoracotomy c. Continue with Chest tube drainage d. CT guided aspiration of pleural fluid

Answer 42

Pleurodesis: a procedure in which pleural space is artificially obliterated. Involves the adhesion of the 2 pleurae. 1500cc