First Aid Pathology Pt 1

Question 1

What causes rhinosinusitis and what does it cause?

Answer 1

Obstruction of the sinus drainage into the nasal cavity which causes inflammation and pain

Question 2

Which sinus is typically affected in rhinosinusitis?

Answer 2

The maxillary sinuses which drain against gravity as the Ostia is located superomedially

Question 3

What does the superior, middle and inferior meatus of the nasal cavity drain?

Answer 3

Superior: sphenoid, posterior ethmoid
Middle: frontal, maxillary and anterior ethmoid
Inferior: nasolacrimal duct

Question 4

What is the most common acute cause of rhinosinusitis?

Answer 4

Viral URI which can lead to a superimposed bacterial infection (most commonly H. influenza, S. pneumonia, M. catarrhalis)

Question 5

Where might paranasal sinus infections extend to and what can happen as a result?

Answer 5

Orbits, cavernous sinus, and brain

May cause: orbital cellulitis, cavernous sinus syndrome, meningitis

Question 6

What is epistaxis and where does it most commonly occur? Name four common causes

Answer 6

Nose bleeds, most commonly occur in the anterior segment of nasal cavity. Common causes include trauma, foreign body, allergic rhinitis and nasal angiofibroma

Question 7

Where do life-threatening hemorrhages (epistaxis) commonly occur and why?

Answer 7

The posterior segment of the nasal cavity as this is where the sphenopalatine artery is (a major branch of the maxillary artery)

Question 8

What is a nasal angiofibroma and what group of people are more commonly affected by it?

Answer 8

Benign but locally aggressive vascular tumour of the nasopharynx (grows in the back of the nasal cavity), most commonly affects adolescent males

Question 9

What are the arteries supplying the Kiesselbach plexus of the nasal septum?

Answer 9

Kiesselbach drives his LEXUS with his LEGS

• Labial artery
• Posterior and anterior ethmoidal artery
• Greater palatine artery
• Sphenopalatine artery

Question 10

What is the most common kind of head and neck cancer? Name four risk factors

Answer 10

SCC is the most common

RFs: tobacco, alcohol, EBV (nasopharyngeal), HPV-16 (oropharyngeal)

Question 11

What is field cancerization? How does it affect the head and neck and parts of the body in general?

Answer 11

When a carcinogen damages a large area of the mucosal surface, this causes multiple tumours to arise independently after one exposure

Question 12

What predisposes you to a DVT?

Answer 12

SHE

S: Stasis
H: Hypercoagulability (clotting protein defect (like factor 5 Leiden), OCP, pregnancy)
E: Endothelial damage, as collagen exposure triggers the clotting cascade

Question 13

How does pregnancy increase the risk of a DVT?

Answer 13

Increase in clotting proteins (due to placenta), and the uterus can place increased pressure on the veins causing stasis

Question 14

Where do most pulmonary emboli arise from?

Answer 14

The proximal deep veins of the lower extremity

Question 15

What is the D-dimer lab test used for clinically? What does a high D-dimer

Answer 15

Used to rule out a DVT in low-moderate risk patients (as it has a high sensitivity but low specificity)

A high d-dimer indicates high levels of fibrin degradation products and lots of thrombus formation and breakdown – but won’t tell you location or cause

Question 16

How is a DVT managed…

a) for prophylaxis and acute management
b) for treatment and long-term prevention

Answer 16

a) Unfractionated or low molecular weight heparin (like enoxaparin)
b) oral anticoagulants like warfarin

Question 17

What is the imaging test of choice for a DVT?

Answer 17

Compression ultrasound with doppler

Question 18

What is the imaging test of choice for a PE and why?

What abnormality might be present on an ECG?

Answer 18

CT pulmonary angiography as it can visualize filling defects, which are thrombi in situ caused by stasis (not PEs)

ECG: SQI3T3

Question 19

What can happen as a result of large emboli or saddle embolus in the lungs?

Answer 19

Sudden death due to electromechanical dissociation (pulseless electrical activity)

Question 20

How can a PE induce respiratory alkalosis?

Answer 20

Causes a V/Q mismatch which induces hypoxia and hyperventilation

Question 21

Name four ‘sudden-onset’ symptoms that might occur in a patient with a PE

Answer 21

Dyspnea, pleuritic chest pain, tachypnea and tachycardia

Question 22

What forms the lines of Zahn and what do they indicate?

Answer 22

Lines of Zahn are interdigitating areas pf pink (platelet and fibrin) and red (RBCs) found in thrombi ONLY before death, and thus can help distinguish pre and postmortem thrombi

Question 23

What are the six types of emboli?

Answer 23

FAT BAT

F: fat
A: air 
T: thrombi 
B: bacteria 
A: amniotic fluid 
T: Tumour

Question 24

What is associated with a fat embolus and how does it usually present

Answer 24

Fracture at the end of long bones and liposuction: presents with the classic triad of neurological abnormalities, hypoxemia and petechial rashes (little red spots on the skin as a result of excessive bleeding)

Question 25

What can cause an air embolus and how is it treated

Answer 25

1. Nitrogen precipitating in the blood (of ascending divers), can be treated with hyperbaric O2
2. Iatrogenic (i.e after a central line placement).

Question 26

What three vessels are most commonly used for central line placements?

Answer 26

Femoral vein, subclavian vein, internal jugular vein

Question 27

When and why do amniotic fluid emboli tend to occur? What can they lead to and how common are they?

Answer 27

Tend to occur during labour or postpartum, but can be due to uterine trauma. Can lead to a DIC (disseminated intravascular coagulation; blood clots forming throughout the body which can occlude the small vessels)

Rare but high mortality

Question 28

What structures are contained in the normal mediastinum?

Answer 28

HEAT L: Heart, esophagus, aorta, thymus, lymph nodes

Question 29

What pathologies commonly occur in the anterior, middle and posterior mediastinum?

Answer 29

Anterior: 4Ts; thymic neoplasm, thyroid (substernal goitre), teratoma, “terrible” lymphoma

Middle: esophageal carcinoma, metastasis, hiatal hernia, bronchogenic cysts

Inferior: neurogenic tumours (ie neurofibroma), multiple myeloma

Question 30

What is mediastinitis and why commonly causes it?

Answer 30

Inflammation of the mediastinal tissue, commonly due to…

1. postoperative complications of cardiothoracic procedures (will present in <14 days)
2. Esophageal perforation
3. The continuous spread of odontogenic/retropharyngeal infections

Question 31

How does mediastinitis commonly present?

Answer 31

FTLCS: Fever, temperature, leukocytosis, chest pain and sternal wound drainage

Question 32

What is a pneumomediastinum and how can it be caused?

Answer 32

Presence of air (typically gas) in the mediastinum. Can be caused
1. Spontaneously: Rupture of a pulmonary bleb (small air bubble between the lung and visceral pleura)

2. Caused by trauma, iatrogenic, Boerhaave syndrome

Question 33

What causes Boerhaave syndrome (including the causative symptoms)

Answer 33

Esophageal rupture due to increased intraesophageal pressure and negative intrathoracic pressure, can occur with vomiting and severe straining

Question 34

What happens as a result of ruptured alveoli in a pneumomediastinum

Answer 34

Air goes into the mediastinum via the peribronchial and perivascular sheaths

Question 35

What are the clinical features of pneumomediastinum?

Answer 35

CDVSH: chest pain, dyspnea, voice change, subcutaneous emphysema, (+) Hammond’s sign (crackles on cardiac auscultation)