Anaesthetic Calculations Flashcards
what are the main non-rebreathing systems?
bain
magill
paralell lack
t-piece
why do we need a breathing system?
deliver oxygen
deliver VA
remove waste - VA and CO2
what breathing system has it’s reservoir bag on the inspiratory limb, has a circuit factor of 1 and APL valve at the machine end?
lack
what breathing system has it’s reservoir bag on the expiratory limb, has a circuit factor of 2-3, APL valve at the machine end and is coaxial?
bain
what breathing system has unidirectional valves, has a soda lime canister and is very economical to run?
circle
what breathing system has it’s reservoir bag on the expiratory limb, has a circuit factor of 2-3 and is not coaxial?
t-piece
what breathing system has it’s reservoir bag on the inspiratory limb, has a circuit factor of 1 and APL valve at the patients mouth?
magill
what non-rebreathing systems are suitable for IPPV?
those with the bag on the expiratory limb -
t piece and bain
circle
what breathing systems are not suitable for IPPV?
those with the bag on the inspiratory limb
lack and magill
(can provide IPPV in the short term and on high flow)
what is the circuit factor of the t-piece and bain?
2-3
what patient size is a t-piece suitable for?
<10kg
what patient size is a lack suitable for?
> 10kg to <25-30kg
what patient size is a bain suitable for?
> 8 to <15-25kg
what patient size is a magill suitable for?
> 5kg
what patient size is a circle suitable for?
> 10kg
what is the circle factor of a lack and magill?
1
how is fresh gas flow calculated?
minute volume x circuit factor
how is minute volume calculated?
body weight x tidal volume x resp rate
what is the value of tidal volume?
10 ml/kg
how can bag size be calculated?
calculate patient tidal volume (bw x 10ml/kg)
times TV by 3 and 6 to calculate a range - bag should comfortably accommodate this and not be to large
what is the equation used to calculate drug dosages?
patients weight (kg) x drug dose (mg/kg) /strength of drug mg/ml
how do you convert micrograms to milligrams?
divide by 1000
how can a % be converted to mg?
x10
