Test 1: 9 breathing systems Flashcards
purpose of breathing system
O2 in
deliver anesthetic gas
remove CO2
control ventilation
rebreathing system has — flow of gas through the system and does what to CO2
unidirection
absorbs
non rebreathing system have — valves and does what to CO2
No unidirectional valves
No CO2 absorbent- relys on high FGF to remove CO2
steps of rebreathing system
what controls full, partial or non rebreathing system
amount of O2 flow and the amount of gas reused
at O2= metabolic demand= full rebreathing, no waste
at O2> metabolic demand, low flow causes less waste
if very high flow rate- non rebreathing system (fan in face)
why do you use low FGF
less waste
less environmental contamination
preserves heat
cons of using low FGF
decreased anesthetic gas delivery (at same vaporizer setting)
slower changes in anesthetic concentration
fresh gas inlet in circle system leads to a one way valve that opens during —
inspiration
allows air in but during exhale is closed so no air goes backwards
what is the dead space in the breathing circuit tubing?
the area when inhale and exhale mix (Y piece or before the purple tube)
how to measure reservoir bag
1L per 10 kg
(5-10 x TV (10-20 ml/kg))
in circle system that expiratory one way valve leads to the —
reservoir bag
valve is open during exhale and closed during inhale (allows unidirectional flow only)
when to open or close the pop off valve
always open during spontaneous ventilation (if closed can lead to pneumothorax!)
close to manually breathe for patient
how to rid inhalant safely from circle system
vented outside
absorbed by F-air canister (scabvenging system)
carbon dioxide absorbers work by
change color(white to pink) and become hard → need to replace
base (absorbent) neutralizes acid (CO2) →H20 + carbonate + heat
types of CO2 absorbents
soda lime - most common
baralyme (barium lime)
amsorb (calcium hydroxide lime- nexest)