Week 140 - Septic and Anaphylactic Shock

Question 1

What is the equation for oxygen delivery?

Answer 1

Oxygen Delivery = blood flow x [Hb] x oxygen saturation

Question 2

What are the types of shock?

Answer 2

Hypovolaemic shock =
Cardiogenic shock = failure of heart
Obstructive shock (embolism, tension pntx, tamponade)
Maldistributive shock = abnormal dilation of small arteries

Question 3

What is the equation for blood pressure?

Answer 3

BP = COxTPR

Question 4

What happens in septic shock?

Answer 4

Vessels leaky -> hypovolaemia
Cytokine storm -> cardiogenic shock
DIC
Mitochondrial failure (can cause cell death even when O2 plentiful)

Question 5

What is anaphylactic shock?

Answer 5

Extreme type 1 hypersensitivity reaction to a previously met antigen
Smooth muscle in bronchi usually contracts
Oedema and bronchospasm causes wheeze

Question 6

What symptoms characterise shock?

Answer 6

Alterations to conscious level
↑RR
↑HR
Hypotension
Poor peripheral perfusion
↓Urine Output

Question 7

What nerve innervates all muscles of larynx?

Answer 7

Vagus Nerve

Question 8

What nerve innervates all pharynx muscles (except stylopharyngeus)?

Answer 8

Vagus Nerve

Question 9

What nerve innervates stylopharyngeus muscle?

Answer 9

Glossopharyngeal Nerve (IX)

Question 10

What muscle causes Abduction of the vocal cords?

Answer 10

Posterior cricoarytenoid

Question 11

What is Reinke’s Oedema?

Answer 11

Oedematous and distended vocal cords

Question 12

What can trauma to vocal folds given rise to?

Answer 12

Vocal fold nodules (bilateral)

Vocal fold polyps (singular)

Question 13

What is the function of the palatopharyngeal sphincter?

Answer 13

When superior constrictor closes during swallowing, the sphincter seals the pharyngeal isthmus between the nasopharynx

Question 14

What is the sensory distribution of the pharynx?

Answer 14

Nasopharynx = pharyngeal branch of maxillary nerve (V2)
Oropharynx = CNIX
Laryngopharynx = CNX

Question 15

What is Waldeyer’s tonsillar ring?

Answer 15

Ring shaped arrangement of lymphoid tissue in the pharynx

Question 16

What is Quinsy?

Answer 16

Peritonsillar abscess (complication of tonsilitis)

Question 17

What is Sepsis?

Answer 17

Systemic inflammatory response to infection marked by characteristic haemodynamic disturbance and organ dysfunction

Question 18

What is Severe Sepsis?

Answer 18

Sepsis with signs of hypoperfusion, hypotension or organ dysfunction

Question 19

What is Septic Shock?

Answer 19

Sepsis with refractory hypotension

Question 20

What can splenic malfunction/absence cause?

Answer 20

Humoral immunodeficiency + impaired clearance of encapsulated bacteria (Pneumococcus, H. influenzae, Meningococcus)

Question 21

What is the Cardiac Output equation?

Answer 21

CO= HRxSV

Question 22

What is the Delivery of O2 equation?

Answer 22

DO2 = CO x [ArtO2]

Question 23

Where is 2/3 of blood located?

Answer 23

In veins and venules

Question 24

Where does most of the TPR come from?

Answer 24

Arteries and Arterioles

Question 25

What do arterial dilators decrease?

Answer 25

TPR (and therefore BP)

Question 26

What do veno dilators decrease?

Answer 26

SV (and therefore CO-->BP)

Question 27

What are the effects of adrenaline?

Answer 27

Low dose-> β1 (HRxSV=CO) | High dose -> α1 (vasoconstriction)

Question 28

What are the effects of noradrenaline?

Answer 28

Potent vasoconstrictor | Significant s/e profile (necrosis of finger tips, toes)

Question 29

What is the action of nitrates (e.g. GTN)?

Answer 29

Produces NO -> increased cAMP -> reduced Ca Venous dilation -> ↓Venous Return ↓Preload -> ↓Myocardial Oxygen Demand

Question 30

What procoagulant-anticoagulant balance disturbances occur in shock?

Answer 30

↑Tissue Factor Production (↑pro-coag) | ↓Plasminogen activator inhibitor, thrombodulin, protein C (↓anti-coag)

Question 31

What are the types of hypersensitivity reactions?

Answer 31

Type I - Immediate Hypersensitivity (hay fever, anaphylaxis) Type II - Antibody-mediated (myasthenia gravis, Graves) Type III - Immune complex-mediated (RA, SLE) Type IV - Cell-mediated (contact dermatitis, transplant rej)