What is replaced in a machine when the ventilator is turned on
-the reservoir bag within the breathing system is replaced
What is the function of a machine selector valve
- allows the selection of manuel or mechanical ventilation
- it isolates the APL valve from the rest of the system
What are the Anesthesia ventilators power sources
- compressed gas
- electricity
- or both
What is the power source for contemporary bellows
compressed gas and electricity
what is the power source for modern piston ventilators
electricity
How are Bellows arranged on a machine
- inside a chamber that separates driving gas from from the breathing system gases.
- the inside of the bellow is connected to the breathing system
How are bellows classified
- classified by how they move during EXPIRATION
- ascending/standing- rise/fill on exp and fall/empty on insp. most common
Why is a hanging bellow detrimental
- unrecognizable patient disconnect
- will continue to fill and empty if patient is disconnected from vent
the ventilator control panel includes
- tidal volume: 10-15ml/kg
- resp rate
- some vents allows adjustment of minute vent (MV) to determine TV
- TV=MV/RR
- I:E ratio
what are the components of a scavenging system
- gas collection assembly(tubes connected to APL and vent relief valve
- transfer tubing (yellow, 19 or 30mm)
- scavenging interface
- gas disposible tubing (carries gas from interface to disposible assembly)
- gas disposible assembly (active or passive)
How does an Active scavenging system work
- connects to hospital sunction system
- 3 liter reservoir bag is present which holds excess gas until it can be removed
- vaccum control valve is adjusted to 10-15 l of waste per minute
how is a patient protected from the active scavenging system
-the positive and negative pressure relief valve protects the pt from the negative pressure of the vacuum system and positive pressure of an obstruction in the disposal system
How does a Passive scavenging system oporate
- interfaces with the hospital ventilation duct
- relies on the build-up of gases in the bag to passively empty into the hospital vent system
the high pressure system consist of
- those parts that receive gas from cylinder pressure (psi @ or > 45)
- hanger yoke
- hanger yoke check valve
- cylinder pressure regulator
- cylinder pressure guage
Intermediate pressure system consist of
- parts that receive gas at a low constant pressure (35-45psi/pipeline pressure)
- pipeline inlets and pressure gauges
- vent power outlet accessory
- O2 flush valve
- supply failure alarm system
- second stage pressure regulator
- flowmeter valves (< 16 psi, before needle)
Low pressure system consist of
components distal to the flowmeter needle
- flowmeter tubes
- vaporizers
- temp compensating bypass valve
- common gas outlet
