anesthesia

Describe the flow of oxygen into the anesthesia machine

1. oxygen cylinder

2. pressure regulator

3. metal pipes (intermediate pressure)

4. flexible pipes that drop from ceiling

5. flowmeter (oxygen is reduced to low pressure)

6. vaporizer and mixes with iso

7. common gas outlet

8. inspiratory one way valve

9. inspiratory limb to patients lungs during inhalation and some in reservoir bag

Describe the theory of operation of the anesthetic machine

1. oxygen enters the machine at the lower back of the flow meter

2. oxygen enters the flowmeter near top

3. oxygen enters the reservoir bag and the inhalation tube then is inhaled by the patient

4. the patient exhales and waste gas enters the machine

5. waste has enters the CO2 absorber canister which removes the CO2

6. gas without CO2 enters the reservoir bag, inhalation tube and patient, recycling the gas

7. a small amount of waste gas exits the APL valve, maintaining pressure in the machine

describe how a leak test is performed

1. close the APL valve

2. occlude the patient end of the breathing circuit with a small reservoir bag

3. activate the oxygen flush valve and allow the reservoir bag to become completely full until the pressure gauge on the anesthesia machine reads 20 cm

4. observe the pressure gauge and ensure that the pressure remains fixed at 20 cm

5. once there is no leak at 20, release the pressure from the anesthesia machine

6. open APL valve

7. empty the reservoir bag into scavenging system

8. remove the reservoir bag from patient end

describe how to quantify a leak in the anesthesia machine

• The CO2 absorbent canister – make sure it is tightened.

• Check unidirectional valve domes and make sure that they are tightly fit.

• Check reservoir bag for possible damage or tears (move your hands along the surface of the reservoir bag).

• Check the common gas outlet to make sure the adaptor is tightly secured.

• Check the rubber tube connectors to ensure they are tightly secured.

• Ensure the APL valve is closed.

• Set the flow meter to 0.2 Liters/minute or 200mls/minute.

• Increase the pressure back to 20cmH20 by activating the Oxygen flush valve.

• The pressure will remain at 20cmH20 if the leak is 0.2L/min.

• If the pressure continues to reduce, then communicate with the instructors.

describe how to release the pressure from the anesthesia machine after quantifying the leak observed

1. open APL valve

2. turn off the flowmeter

3. empty reservoir bag (squeeze it)

4. remove reservoir bag from patient end

describe how to assemble a bain block non rebreather system

1. attach bain block to the pipe on the anesthesia machine where the reservoir bag is placed for a circle system

2. remove common gas outlet adaptor for rebreathing system and attach common gas outlet adaptor for non breathing system

3. attach common gas outlet adaptor for bain system to common gas outlet

4. attach the scavenging tube to the interface mounted to the anesthesia machine

describe how to perform a leak test for bain non-rebreathing system

1. Connect the adaptor of the flexible oxygen pipe hanging from the roof to the adaptor of the flexible pipe connected to the anesthesia machine.

2. 2

   Connect the scavenging tubes hanging from the ceiling to the adaptor of the scavenging tube connected to the anesthesia machine.

3. 3

   For the outer (expiratory) limb: Same as rebreathing system but use the flowmeter to increase the pressure in the machine to 20cmH20 instead of the oxygen flush valve. (DO NOT USE THE OXYGEN FLUSH TO INCREASE THE PRESSURE IN THE ANESTHESIA MACHINE, WHEN PERFORMING A LEAK TEST ON THE NON-REBREATHING SYSTEM).

4. 4

   ALWAYS CHECK TO ENSURE YOU HAVE OPENED THE APL VALVE ON THE BAIN SYSTEM.

5. 5

   THE APL VALVE MUST NEVER BE LEFT CLOSE.

6. 6

   For the inner (inspiratory) limb: Turn flowmeter to approx. 1L. With your finger or a pen occlude only the inner tube. Observe the flowmeter – in the absence of leak the sphere or bobbin of the flowmeter should move down.

describe the order and placement of equipment used in JSAL

1. capnograph

2. pulse ox

3. BP cuff

4. EKG

5. esophageal stethoscope and thermometer

6. doppler blood pressure