General Primary MCQ6 Flashcards
Concerning the spectrum of electromagnetic radiation:
a) the visible spectrum spreads from 390 nm to 750 nm
b) X-rays and gamma rays are ionising radiations
c) the CO2 laser gives infrared radiation
d) ultraviolet rays are non-ionising
e) wavelength is inversely related to frequency
TTTTT
Halothane:
a) has a marked arrhythmogenic potential compared with other currently used volatiles
b) is a racemic mixture of optical isomers
c) has a minimal alveolar concentration of 0.29 in 70% of nitrous oxide
d) is metabolised to the greatest extent amongst currently available agents
e) sensitises the myocardium to endogenous or exogenous catecholamines
TTTTT
For intravenous anaesthetic agents:
a) the end point of induction of anaesthesia is loss of the eyelash reflex
b) the clearance is their rate of excretion
c) lower doses will be required for induction in hypovolaemic patients
d) the effects on the CNS. depend on their degree of ionisation
e) their non-protein bound fraction increase in liver and renal diseases
FFTTT
Enflurane:
a) is less potent than isoflurane
b) causes convulsive EEG pattern when used at high concentration in the presence of hypocapnia
c) decreases intracranial pressure
d) impairs the autoregulation
e) does not affect cerebral blood flow
TTFTF
Ketamine:
a) has marked analgesic properties mediated by its binding to NMDA receptors
b) causes a fall in cardiac output and a rise in heart rate
c) is contraindicated in patients with raised intracerebral pressure
d) has active metabolites
e) causes postoperative dreaming and hallucinations which are less frequent in children
TFTTT
With regard to acids and bases:
a) acids can be considered as H+ ion donors
b) water can act as both an acid and a base
c) pH is log 10 [H+]
d) physiological systems control Na+ concentration within more closely defined limits than H+ concentration
e) lactic acidosis is a normal `anion-gap’ acidosis
TTFFF
The following characteristics of a drug intended to be given by infusion are desirable:
a) short elimination half-life
b) high rate of plasma clearance
c) low cost
d) low aqueous solubility
e) administration via a central vein
TTTFF
The effects of acidosis may include:
a) increased minute ventilation
b) shift of the oxygen dissociation curve due to the Bohr effect
c) negative inotropism due to higher calcium levels
d) hyperkalaemia
e) increased NH4 excretion
TTFTT
Concerning buffers:
a) buffers are least efficient when half dissociated
b) carbonic anhydrase is an important component of the physiological buffering system
c) phosphate is an important extracellular buffer
d) oxygenated haemoglobin is a more powerful physiological buffer than deoxygenated haemoglobin
e) the imidazole ring structure of haemoglobin is the site of H+ exchange for physiological buffering
FTFFT
A competitive antagonist:
a) combines with the same receptor as the agonist drug
b) shifts the log dose-response curve for the agonist to the right
c) depresses the maximum obtainable response of the agonist
d) may affect the affinity of the agonist for its receptors
e) need not have a close structural similarity to the agonist
TTFFT
Concerning body fluid compartments:
a) water constitutes 70% of the total body weight
b) plasma constitutes a quarter of the extracellular fluid (ECF) volume
c) sucrose can be used to measure the ECF volume
d) the interstitial fluid volume for a 70 kg man is approximately 9 litres
e) The ECF/intracellular fluid volume ratio is smaller in infants and children than it is in adults
FTTTF
When the ventilation/perfusion ratio of a lung unit increases:
a) the alveolar PO2 rises
b) the alveolar CO2 rises
c) end capillary PO2 increases
d) arterial PO2 increases
e) hypoxic pulmonary vasoconstriction will compensate for any change in gas exchange
TFTTF
In the type I immune reaction in man:
a) the antibody is always IgE
b) an antigen-antibody reaction occurs on the surface of mast cells
c) most of the clinical manifestations are due to the release of kinins from mast cells
d) anaphylaxis occurs only in atopic individuals
e) bronchoconstriction may follow inhalation of reagin
TTFFT
When a patient is using a monoamine oxidase inhibitor, the following drugs should be avoided:
a) halothane
b) pethidine
c) adrenaline
d) dopexamine
e) phenylephrine
FTTTT
The following statements about diuretics are correct:
a) amiloride causes hyperuricaemia
b) thiazides improve carbohydrate tolerance
c) loop diuretics reduce renal calcium loss
d) loop diuretics potentiate nephrotoxicity of cephalosporins
e) thiazides may prevent renal colic in patients with idiopathic hypercalcaemia
FFFTF
- thiazides cause hypercalcaemia and raise blood sugars and cause gout (hyperuricaemia)
