Pharma MCQ 8 Flashcards
BG Coefficient: Xenon
0.2
BG Coefficient: Desflurane
0.42
BG Coefficient: N2O
0.47
BG Coefficient: Isoflurane
1.4
BG Coefficient: Halothane
2.5
Which of these have a BG Coefficient > 1?
Xenon, Desflurane, Nitrous Oxide, Isoflurane, Halothane
Isoflurane and Halothane
How does thiopental exert its effect on respiration?
Thiopental causes respiratory depression by a direct effect on the respiratory centre in the medulla rather than on peripheral chemoreceptors.
Thiopental protein binding?
80%
Thiopental metabolism and clearance?
Its action is terminated by redistribution
and hepatic metabolism is SLOW.
Resistance to non-depolarising relaxants may be produced by:
- hypothermia
- phenytoin
- lithium
- hypocalcaemia
- carbamazepine
Phenytoin and Carbamazepine
Resistance to aminosteroid neuromuscular blockers can occur with chronic medication with anticonvulsants phenytoin and carbamazepine.
Which is more potent, lidocaine or ropivocaine?
Ropivocaine is 4 times more potent.
Plasma binding cocaine?
98%
Plasma binding amethocaine?
75%
Prilocaine, ester or amide?
Amide
Effect of metabolic products of prilocaine?
O-Toluidine
- allergic reaction
- reduces Hb
- methaemoglobinaemia in high doses
Can prilocaine be used for obstetric epidural anaesthetist?
NO, AVOID.
Prilocaine should be avoided for obstetric anaesthesia because fetal haemoglobin is more susceptible to methaemoglobin formation
TCA, mechanism of action?
Tricyclic antidepressants have several actions including inhibiting presynaptic re-uptake:
- norepinephrine
- epinephrine
- 5-hydroxytryptamine (serotonin)
but do not affect metabolism per se.
How do benzodiazepines effect brain physiology?
Benzodiazepines are relatively lipid soluble and penetrate the blood brain barrier readily.
> > > DOSE RELATED: decrease cerebral blood flow and cerebral oxygen consumption.
True or false: Benzo have depressant effects dull after long-term use?
True,
long-term use -> tolerance.
ICP in a ventilated patient is increased by which of the following:
- Desflurane
- Nitrous oxide
- Fentanyl
- Vecuronium
- Ketamine
Desflurane - vasodilation above MAC 1
Ketamine - increases CBF and ICP
