The Anesthesia Machine Flashcards
(32 cards)
What percent of air is oxygen?
21%
T/F: It is ideal to deliver anesthetic gas in air.
False, air is only 21% so it would lead to hypoxemia due to hypoventilation and V/Q mismatch induced by anesthetics themselves.
The minimum FiO2 acceptable for people and small animals is ________.
FiO2 = 0.3-0.35 (30-35% O2)
The minimum O2 flow required is ________.
5-10ml/kg/min
A dog weighs 13kg. Knowing that the minimum O2 flow required is 5-10ml/kg/min, what is the minimum metabolic oxygen requirement for this dog?
65-1300ml/kg/min
(To solve, multiply the weight of the animal by the low and high range of the requirement, so 13x5 = 65 and 13x100 = 1300)
Which of the following correctly matches a compressed gas with its tank colour?
A) oxygen = blue, medical air = yellow, nitrous oxide = green
B) oxygen = white, medical air = blue, nitrous oxide = yellow
C) oxygen = green, medical air = yellow, nitrous oxide = blue
C! Oxygen = green, medical air = yellow, nitrous oxide = blue
Which of the following is FALSE regarding tank safety?
A) never leave an unsecured tank sitting upright
B) tanks can explode if they are dropped or fall over
C) Clean oils from hands and tank and open the cylinder valves quickly
D) Open and close valves briefly before attaching to machine to remove dust from connecting port
C - you don’t want to open the cylinder valves quickly! The first half of the sentence is true, but you want to open the valves slowly
T/F: In regards to pressure gauges, cylinder pressure is usually in cmH2O (centimetres water) and breathing system pressure is in psi (pounds per square inch).
FALSE! Other way around - cylinder pressure is in psi, breathing system pressure is in cmH2O
Which of the following is not a high pressure (100-2200+ psi) system? A) gas cylinder B) central O2 supply C) yokes D) pressure gauges E) regulators
B - central O2 supply is intermediate pressure (50 psi)
Which of the following is not an intermediate pressure (50 psi) system? A) central O2 supply B) post-regulator C) flush valve D) input to flow meter E) patient's lungs F) driving gas for ventilator
E - patients lungs are low pressure (<15 psi)
2 places that would have a pressure <15 psi?
1) between flowmeter output and common gas outlet
2) breathing system (= pressure in patient’s lungs)
Which is the most common oxygen cylinder used in small animal practice? What is the capacity?
E cylinder, capacity = 660L
The capacity of an H oxygen cylinder is _____.
6600 L
T/F: both E and H oxygen cylinders are filled to a pressure of 2200 psi.
True
What is the Boyle’s law equation that relates volume to pressure?
P1V1=P2V2
You want to do surgery on a dog and estimate you will need 1 hour from start of induction to finish. Your E cylinder gauge shows 300 psi. The O2 flow rate will be 2 L/min. Do you have enough O2 in your tank to complete the procedure?
First, 2200psi/660L = 300psi/X
solve for X = (300psi x 660L)/2200psi
X = 90
mins remaining = X liters/(Flow L/min)
= 90L/(2L/min)
mins = 45
Therefore you would not have enough for a one hour procedure!
You have an N2O tank and want to calculate how much remaining gas you have. What is your method?
A) P1V1=P2V2 calculation
B) Shake it and see if you can read its mind
C) weigh it
C - weigh the tank
This safety system utilizes a non-interchangeable gas specific threaded connection system. A) Quick connectors B) Labelling C) Pin index safety system D) Diameter index safety system
D - diameter index safety system
This safety system involves gas specific pin patterns that only allow connection between the appropriate cylinder yokes and E tanks. A) Quick connectors B) Labelling C) Pin index safety system D) Diameter index safety system
C - Pin index safety system
This safety system facilitates rapid connecting and disconnecting of gas hoses. A) Quick connectors B) Labelling C) Pin index safety system D) Diameter index safety system
A - quick connectors
This part of the anesthesia machine decreases tank pressure to a safe working pressure (~50psi). A) flowmeter B) regulator C) quick flush D) pressure gauge
B - regulator (also known as pressure reducing valve)
Which of the following is TRUE regarding the flowmeter?
A) The flow is read at the top of the ball or the middle of the bobbin
B) Gas exits the top at 50psi
C) O2 should be downstream of other gases if there are multiple flowmeters
D) It increases gas pressure
C is true
A - is the other way around
B - gas enters at 50psi and exits at 15 psi
D - it decreases gas pressure
Pressure of the gas that exits the flow meter is _____.
15 psi
Which of the following is FALSE regarding the quick flush?
A) it bypasses the vaporizer
B) it delivers gas at a rate between 35-75 L/min directly to the patient circuit
C) patient should be disconnected from circuit before O2 flush valve is utilized
D) it contains concentrated amounts of anesthetic agent
D - it bypasses the vaporizer so it has no anesthetic agent
