Respiratory

Question 1

5 causes of hypoxia

Answer 1

Right to left shunting
Hypoventilation
Low inspired oxygen
V/Q mismatch
Diffusion impatient

Question 2

6 groups of pulmonary hypertension

Answer 2

Arterial pulmonary hypertension
Left-sided heart failure
Pulmonary disease/hypoxia
Emboli, thrombus, thromboembolic
Parasitic
Unknown or multifactorial

Question 3

What is beaking?

Answer 3

Reflects further increase in circuit pressure with minimal additional volume increase

Question 4

How would a circuit leak appear on a PV loop on MV

Answer 4

An open, broken, incomplete loop

Question 5

Criteria for failure of a spontaneous breathing trial as per SACCM 2023

Answer 5

Tachypnoea (RR> 50)

PaO2 <60mmHg or SpO2 <90%

PaCO2 >55mmHg or PvCO2 > 60mmHg or ETCO2 > 50mmHg

Tidal volume <7ml/kg

Tachycardia

Hypertension

Hyperthermia or increase in temp >1 degree Celsius

Anxiety

Signs of increased respiratory effort or distress

Clinical judgement

Question 6

What is the definition of hypoxemia?

Answer 6

Partial pressure of oxygen (PaO2) of less than 80mmHg or arterial blood Hb saturation of <95% (SaO2 or SpO2)

Question 7

What 6 conditions could lead to loss of lung slide?

Answer 7

Pneumothorax
Pleural effusion
Pleural space occupying structure
Consolidation
Pleural adhesions
Over inflated lung (asthma)

Question 8

What are the sensors for central control of breathing?

Answer 8

Central chemoreceptors (medulla)
Blood co2 diffuses into CSF and leads to increase in hydrogen ions/decreased pH

Retrotrapezoid nucleus

Question 9

In pressure control MV what is the dependent variable

Answer 9

Volume

Question 10

Name the phases of the capnograph

Answer 10

1 flat
2 increase
3 plateau
4 decrease

Question 11

What is a curate cleft on a capnograph and what does it represent

Answer 11

It is a divot at the alveolar plateau and represents the patient trying to take a breath

Question 12

What is a curate cleft on a capnograph and what does it represent

Answer 12

It is a divot at the alveolar plateau and represents the patient trying to take a breath

Question 13

What are the numbers on a capnograph

Answer 13

1= flatline
2= expiratory downstroke
3= alveolar plateau
4= inspiratory downstroke

Question 14

What would a shark fin capnograph represent

Answer 14

Obstruction/bronchospasm

Question 15

Name 7 mechanisms of VILI

Answer 15

Barotrauma
Bio trauma
Atelectrauma
Volutrauma
Mechanical power
O2 toxicity
Spontaneous breathing