Anesthetic machine lab Assignment 2

Anesthetic Machine & Breathing Systems

Identification of Parts

• E tank of O2

  • Location: Attached to the anesthesia machine.

  • Purpose: Provides oxygen for anesthesia.

  • Operation:

    • Turn on/off O2 using the valve.

    • Pressure gauge indicates remaining oxygen.

    • Bleed the lines by opening the valve after turning off O2.

    • Replace empty E tank by disconnecting and attaching a full tank.

    • Calculate L from psi by using appropriate ratio for the tank size and pressure.

• Pressure Regulator

  • Location: Downstream of E tank, close to the flowmeter.

  • Function: Reduces pressure of O2 from tank to usable levels.

• Flowmeter

  • Location: Following pressure regulator.

  • Function: Measures the flow of oxygen; allows setting of desired flow rate.

  • Operation: Calculate flow settings for rebreathing vs. non-rebreathing systems based on patient needs.

• Vaporizer

  • Location: Attached to the O2 flow after the flowmeter.

  • Functions: Vaporizers convert liquid anesthetic into vaporized form.

  • Types:

    • Precision Vaporizer: Allows controlled delivery of specific anesthetic concentrations.

    • Non-Precision Vaporizer: Less accurate, relies more on flow rates.

  • Operation:

    • Check anesthetic level through the viewing window.

    • Fill with anesthetic by following manufacturer guidelines.

    • Turn on/off using the designated switch.

• Reservoir Bag

  • Location: Attached to the breathing circuit, common in rebreathing systems.

  • Function: Holds a volume of gas used to ventilate the patient and allows for manual ventilation.

  • Operation: Calculate appropriate size based on patient weight; use for ventilating small animal patients.

Breathing Circuit Components

• Unidirectional Flutter Valves

  • Location: One on inhalation side, one on exhalation side of the breathing circuit.

  • Function: Ensures unidirectional flow of gases in the circuit.

  • Operation: Clean properly to prevent obstruction; recognize consequences of stuck valves (i.e., inability to ventilate).

• Oxygen Flush Valve

  • Location: On the anesthesia machine, typically separate button/lever.

  • Function: Directs pure O2 to the breathing circuit.

  • Operation: Use when necessary to increase O2 flow; limit use to avoid dilution of anesthetic gases.

  • Duration: Briefly depress the button for a few seconds only.

Gas Scavenging System

• Scavenge System

  • Location: Attaches to the anesthesia machine, either actively (powered) or passively (through charcoal canisters).

  • Function: Removes waste anesthetic gases from the operating room to prevent clinician exposure.

  • Types:

    • Active Scavenge: Uses suction; typically more effective.

    • Passive Scavenge: Relies on diffusion; less controlled but simpler to set up.

• F/Air Canister

  • Function: Captures exhaled anesthetic gases.

Pressure Regulation and Monitoring

• Pop-Off Valve (Pressure Relief Valve)

  • Location: On the breathing circuit.

  • Function: Prevents excess pressure buildup, maintaining safe levels in the circuit.

  • Operation: Open when patient is breathing normally; close during manual ventilation if necessary.

• CO2 Absorber Canister

  • Location: Usually near the breathing circuit.

  • Function: Absorbs exhaled CO2 to reduce the re-inhalation of carbon dioxide by the patient.

  • Operation: Recognize when granules need changing (typically when exhausted or changed color) and follow steps to replace.

• Pressure Manometer

  • Location: Typically integrated with the breathing system.

  • Function: Measures the pressure within the breathing circuit to ensure safe ventilation.

• Negative Pressure Relief Valve

  • Location: Between the soda lime canister and scavenging system.

  • Function: Prevents negative pressure from forming, ensuring ambient air is drawn in during venting.

Breathing System Selection

• Rebreathing System (Circle System)

  • Use Case: Preferred for larger patients due to efficient re-inhalation of gases.

  • Operation: Proper selection/calculation of components (like appropriate reservoir bag and breathing tubes).

• Non-Rebreather (Jackson-Rees)

  • Use Case: Typically used for small patients due to minimal resistance and fast turnover of gases.

  • Operation: Correctly hook up to anesthesia machine, ensuring all components are accounted for (notably omitting CO2 scrubbers).

Leak Testing the Anesthetic Machine

• Procedure:

  • Attach necessary equipment.

  • Turn on the O2 supply.

  • Close the pop-off valve to build pressure in the system.

  • Use a pressure check device to monitor (typically done using a squeeze bag or manual ventilation).

  • Tips on finding leaks include listening for hissing sounds and checking for drops in pressure over time.