Anesthesia Machine Parts Flashcards
What are the 3 types of valves
1.Free floating : one way 2.Ball and Spring valve : All or none valve 3.Diaphragm: Pressure Reducer Valve
Pressure
one 1L of oxygen , 1000psi may be
All anesthesia machines have about the
same parts
Endoskeleton of the machine
1st stage vs 2nd stage regulator.
one way valve
Free floating inhale : expiratory valve (close) exhale: inspiratory valve (open) expiratory valve open when you exhale E-Cylinder APRV or Pop Off valve (manually operated) Gas flow pushes gas to valve seat
Function of floating Valve
prevent gases from escaping the closed circuit system.
Radicals , macrophages, and eosinophils are mobilized
when the patient is given 100% oxygen
Pop off valve : turned to the right? what happens? Turn to the left –> ?
turned to the right (tighten , all the gas goes to the bag and the patient. Lefty loosy, more of the gas goes out the scavenging system
Pop off valve (APRV)
The more difficult, close more The less difficult, open a little more
One way free floating
from tank to patient, (one way out)
If you have 2 oxygen cylinders 1100 psi vs 1000 which one will deliver the pressure
1100 then both The cylinder with the higher pressure will deliver more oxygen.
DISS wall valve
Diameter Index Safety System (DISS) Idiot proof
Green yellow blue
Oxygen, air, nitrous oxide.
PISS
Pin Index Safety System (E-Cylinder) Different pin for each (Oxygen, nitrous)
Bourdon gauge
it measures pressure generated from its sources (bag, e-cylinder, ventilator or wall) Importance lies when bagging the patient with a mask: STAY below 20cmH2…(adjust pop off valve) Why? Barotrauma, ESOPHAGEAL SPHINCTER will open with 15cmH2O. IF you need to ventilated can go UP , (Smoking, obesity, OSA)
Inhale Know pressure and lung volume End Tidal is the opposite of
peak, plateau , exhale Inspiratory pressure.
Tidal volume x RR
minute ventilation
Ultrasonic flow meter
back of machine, light blue Tall blue dark (The WRIGHT SPIROMETER) measures TV and RR (which is minute ventilation)
Ultrasonic flow meter vs Wright spirometer
Highly accurate not affected by flow situations= Ultrasonic flow meter The wright spirometer= Does not measure volume directly
One way valve All of them measure
Bourdon gauge , ultrasonic flow meter EXHALATION
Expiration vs inhalation
Expiration is longer (passive) normal require passive
Fast ambu bag delivery
it will cause barotrauma.
How long to wait for sats
30 seconds
Alveolar recruitment maneuver (ARM)
Read
Ball & Spring (All or none) Valve
O2 wall connector think of when you applying valve to a wall, (push it in) REQUIRES ENERGY TO ACTIVATE
Flush valve generates ___to ____L/min and can cause __________if pressed too much or can also dilute out the volatile anesthetic being administered.
generates 35 to 75 L/min –> Barotrauma
Diaphragm Function Pressure _____and _____pressure first stage? 2nd stage?
Reduce pressure throughout the system pressure regulator/Reduce pressure First stage: reduce for both O2 and N2O to 40-55psig 2nd stage: Reduces internal intermediate pressure to 15psig (low pressure)
Diaphragm (pressure _____and _____Pressure)
pressure regulator/Reduce pressure First stage: reduce for both O2 and N2O to 40-55psig (intermediate pressure) 2nd stage: Reduces internal intermediate pressure to 15psig (low pressure)
Intermediate (normal)
40-55
Back up pressure
cylinders
Oxygen Fail Safe Mechanisms
Oxygen failure protection device: Flow dependent If oxygen is lower then 25 psig, N2O will shut off
Datex Ohmeda
PROPORTION LIMITING SYSTEM Drager: Limits flow of N2O according to O2 flow.
Thorpe tube:
Tapered and largest at top
From low flow to high flow
Laminar to turbulent AS the diameter increases, you allow for more lamia
For Flowmeters for Ball float
read at middle
For Flowmeters for arrow float
read on top
TEC 6 Desflurane Vaporizer • Heated up to ___________ • Pressurized up to__________
39 degrees Celsius 2 atmospheres.
Soda Lime composition, what are the 3 ingredients
Calcium Hydroxide Sodium Hydroxide Potassium Hydroxide
What is the percentage of calcium hydroxide in the soda lime?
80%
What is the percentage of sodium hydroxide in the soda lime?
4%
What is the percentage of Potassium hydroxide in the soda lime?
1%
Soda lime mesh size ?
4-8
Ethyl violet absorbers are _______when fresh and _______colored when exhausted
white; Purple
What kind of valve in the absorber
Inspiratory or Expiratory Unidirectional valve APL
How many liters of CO2 can the CO2 absorber absorb?
26L
With _____FIRES can occur at ________F
Sevoflurane 400
What do you do if the Soda Lime turns purple and you don’t have time to change it?
Use fresh ga
What do you do if the Soda Lime turns purple and you don’t have time to change it? EX:
Increase the inspiratory flow 3 TIMES the minute ventilation If minute ventilation is 3L/min increase to 9L/min
What is the purpose of increase the respiratory flow
Gas flow out to the scavenging system ; you lose gas bu the patient is SAFE
2 types of ventilators
Ascending Descending Safer is ascending because descending is affected my gravity and may not be reliable
Advantages and disadvantages of Piston ventilators? How is it powered? advantages: is there PEEP, comment on TV, and compliance loss Disadvantages: can generated _________
Piston Ventilators (electric powered) adv: quiet, no peep, greater precision with TV, less compliance losses disadv: less familiarity with standing bellows, quiet operation, cannot use Mapleson circuits; can generate Negative End Expiratory Pressure (NEEP).
The mushroom valve is an
EPRV: expiratory pressure release valve. ▪ One-way (free floating) valve.
Ventilator disconnect alarm 2 types of alarm: ▪ Volume alarms Spirometer Reverse flow Low flow
- pressure alarm - volume alarm
Pressure alarm detect
by a drop in pressure of the system Threshold number
Volume alarm
Spirometer Reverse flow Low flow
CC think compliance is
Chest
Lungs think
Elasticity
Pressure =
Flow x resistance
Compliance = change in volume
change in pressure
Normal Tidal volume is
5ml/kg lowest
Tidal Volume is dependent ?q
- Set tidal volume 2. Flow rate of all gases -Increased flow rates lead to increase TV 3. The set I:E time The longer the inspiratory time the more TV is delivered. Watch for overdistension. 4. Inspiratory flow speed Increasing the flow speed increases the plateau phase leading to increased TV
Increase flow rate increase/decrease TV
Increase
The longer the inspiratory time the (more/less) TV is delivered
More
What increases the plateau phase______leading to ______TV
Increasing the flow speed ; increase TV
What are we trying to achieve? MAD SPM
▪ Safe delivery of minute ventilation ▪ Maintain ETCO2 around 32-36mm Hg ▪ Adequate inspiratory time Maintain alveoli open Do not overdistend alveoli ▪ Prevention of lung injury
Set these 2 parameters together
Rate and I: E time
For respiratory rate of 10 , set I: E at _______so expiratory time is ______seconds
1:2; two
For respiratory rate of 8 , set I: E at _______so expiratory time is ______seconds
1:3 ; 1.88 seconds
For respiratory rate of 6 , set I: E at _______so expiratory time is ______seconds
1:4 ; 2 seconds
How do we go about prevent lung injury ?
- Set rate and I:E time ▪ Set tidal volume ▪ Look at the pressure monitor ▪ Fine tune by changing the flow control ▪ Make sure inspiratory relief valve is above PIP
2 knobs
- Inspiratory flow control dial 2. RR frequency & I:E ratio
What is the Flow Control Dial? what is the function?
Controls the speed of injection of gas around the bellows ▪ Gas is combination of Oxygen and Air ▪ Faster flows increase the PIP ▪ Lower flows will lead to inadequate alveolar ventilation
Open Reservoir Scavenging system: FLow indicator? Relief ports at side does what?
Flow Indicator = ball is at middle portion is 25 L per minute. ▪ Relief Ports at side = suctions room air if there is too much vacuum.
Open Reservoir Scavenging system: receives gas from?
Receives gas from machine through APL and the ventilator.
NIOSH 1977 Recommended Exposure Limits When halogenated only? Halogenated agent and N2O N2O only
*** Halogenated agents only = <2 ppm ▪ *** Halogenated Agent + N20 = 0.5 ppm ▪ *** N20 only = 25 ppm N20
ETCO2 graph b b to c c-d d d to e
(b) Zero: Begin expiration. ▪ (b to c) Ascending: Combination of dead space and alveolar gases. ▪ (c-d) Plateau: Alveolar gases. ▪ (d) End of plateau: ETC02, @ FRC, @end expiration. ▪ (d to e)Descending: Inspiration
Draw this multiple times
CIRCUIT CIRCLE
Describe the circle system
Circle System -> -> ->flow meters –> vaporizer –>Common gas outlet (CGO) –> soda lime –> inspiratory valve –> inspiratory limb of the circuit –> ETT –> patient –> expiratory limb of the circuit –>expiratory valve –> ultrasonic flow meter or Wright spirometer –> bag vs. ventilator lever
Happens simultaneously–>
–> bag –> pop off/ IPRV –> soda lime…etc.—> scavenger. –>ventilator –> soda lime …. Etc. –> mushroom valve –> scavenger.
Circle system function (5)
minimize rebreathing ▪ need for soda lime ▪ dead space ▪ direction of gas flow ▪ required gas flow
02 PATHWAY THROUGH THE MACHINE FROM E CYLINDER
E cylinder –> PISS valve —> bourdon gauge (pressure closes other free floating E cylinder valves) –> First Stage Diaphragm Valve (E cylinder pressure to intermediate pressures) —>
Simultaneously……
▪ oxygen pressure sensor valve ▪ flush valve (bypasses flowmeters and vaporizers —> CGO: common gas outlet) ▪ DISS (closes) ▪ Second Stage Diaphragm Valve (intermediate to low pressure
