General 2 Flashcards
1
Q
- P50:
a) is normally 5.5 kPa
b) is increased at high altitude
c) is an indicator of the position of the oxygen dissociation curve
d) is increased in foetal blood
e) is increased in banked red blood cells
A
1.FTTFF (decreased 2-3DPG in banked RBC’s causes a LEFT shift of curve and therefore DECREASED P50)
2
Q
- The work of breathing:
a) is inversely related to lung compliance
b) increases during exercise
c) normally requires 15% of total body oxygen consumption
d) is increased when the subject breathes heliox instead of room air
e) is calculated by integration of a pressure/volume loop
A
2.TTFFT
3
Q
- Alveolar - arterial oxygen difference (A-a DO2):
a) is normally 2-3 kPa while breathing room air
b) is increased under anaesthesia due to increased V/Q mismatch
c) is decreased in one lung ventilation
d) is increased in the presence of right to left intracardiac shunts
e) is decreased in severe exercise
A
3.TTFTF
4
Q
- Lung compliance:
a) is normally 0.2 L/cm H2O
b) is decreased with loss of pulmonary surfactant
c) is increased in emphysema
d) is decreased after induction of general anaesthesia
e) is different at the apices and bases of lungs
A
4.TTTTT
5
Q
5. An arterial blood sample has the following values: pH 7.25, PCO2 4 kPa, PO2 8 kPa, base excess -5.6 mmol/L, standard bicarbonate 20 mmol/L These could result from: a) an intracardiac left to right shunt b) Acute respiratory distress syndrome c) chronic obstructive airways disease d) aspirin overdose e) diabetic ketoacidosis
A
5.FTFTT
6
Q
- The Magill (Mapleson A) breathing system:
a) is the most efficient system for spontaneously breathing patients
b) will work with minimal rebreathing at a fresh gas flow of 70% of minute volume
c) makes scavenging of exhaled gases easier
d) co-axial version is the Lack system
e) is also efficient during controlled ventilation
A
6.TTFTF
7
Q
- The respiratory centre in the brain stem receives input from:
a) the aortic and carotid bodies
b) bronchiolar stretch receptors via vagal afferents
c) oxygen-sensitive chemoreceptors in the medulla
d) receptors which respond to the hydrogen ion concentration in the cerebrospinal fluid
e) mechanoreceptors of the larynx
A
7.TTFTT
8
Q
- The carotid bodies:
a) have cells which respond only to decrease in PaO2
b) have the highest blood flow (ml/unit weight) in the body
c) maximally stimulate the respiratory centre between 4-8 kPa
d) increase the respiratory drive when mean arterial pressure decreases below 70 mmHg
A
8.FTTT
9
Q
- Concerning pulmonary function tests:
a) FEV1 is low in small airway disease
b) FEV1 is also effort dependent
c) The flow-volume loop can indentify the source of airway obstruction
d) the diffusing capacity of the lung for carbon monoxide is decreased in emphysema
e) FEV1 and PEFR can be used to assess the reversibility of airway obstruction
A
9.TTTFT (Lung compliance increases in emphysema because of the less elastic lung tissue)
10
Q
- Mixed venous oxygen saturation:
a) is normally between 65-80%
b) is essential in calculations of shunt and oxygen extraction ratio
c) is increased in hypothermia
d) is decreased in low cardiac output states and in thyrotoxicosis
e) can be continuously monitored with an oximetric Swan Ganz catheter
A
10.TTTTT
11
Q
- With a decrease in body temperature:
a) P50 and PaCO2 are decreased
b) pH is increased
c) arrhythmias are increasingly common at temperatures below 30 degrees C
d) blood becomes more viscous
e) the EEG becomes isoelectric at about 20 degrees C
A
11.TFTTT
12
Q
- Concerning the pharmacokinetics of inhalational agents:
a) agents with a high blood:gas partition co-efficient will keep alveolar
to inspired gas (FA/FI) ratio low
b) alveolar partial pressure rises faster in adults than in children
c) high cardiac output slows the rate of rise of alveolar partial pressure (FA)
d) diffusion hypoxia is due to the second gas effect
e) the second gas effect slows the rate of rise of alveolar partial pressure (FA)
A
12.TFTFF (2nd gas effect SPEEDS UP the rate of rise of alveolar pp of the inhalational agent)
13
Q
- The following statements regarding inhalational agents are correct:
a) the blood gas partition co-efficient of desflurane is 0.42
b) desflurane can cause sympathetic stimulation
c) sevoflurane can degrade to compound A in soda lime
d) desflurane is suitable for inhalational induction
e) desflurane can be used in halothane vaporiser
A
13.TTTFF
14
Q
- Nitrous oxide (N2O):
a) has a blood:gas partition coefficient of 0.47
b) is 34 times less soluble than N2
c) may be associated with postoperative hearing loss
d) inactivates methionine synthetase after prolonged administration
e) when inhaled at 66% can double a pneumothorax in 10 minutes
A
14.TFTTT
15
Q
- The speed of induction with inhalational agents:
a) is quicker in patients with very high functional reserve capacity
b) is quicker if the agent is very soluble in blood
c) is slower in the presence of right to left shunt
d) is unchanged in the presence of left to right shunt with normal systemic flow
e) is quicker when used with nitrous oxide
A
15.FFTTT