Gas Cylinder Colors
- O2
- N2O
- Air
- CO2
- N
- H
- Green (white)
- Blue
- Yellow
- Grey
- Black
- Brown
Empty E-Cylinder Weight
5.8 lbs
Circle System Check
Extends from CGO to the Y-pieceLeak test: occlude y-piece, close APL, pressurize to 30 mmHg using the O2 flush valve
Machine Check Overview (8 Items)
- Gas Line Connections
- Integrity of seal system/gas pressures
- Low Pressure Circuit Test
- Vaporizer Levels
- Flow Meter Controls
- O2 Analyzer
- Circle Circuit Test/Scavenging System
- Ventilator
*check analyzer by exposing to room air and reading 21%
Intermediate Pressure System (7 Items)
- Master Switch (pneumatic part)
- Pipeline (wall) Inlets (DISS)
- Pipeline Valves, gauges
- Oxygen second stage regulators
- O2 pressure-failure device/alarm
- O2 flush valve
- Flow meter valves
* O2 inlet will be 50 psi, cylinder will be 45-50 or just slightly lower than inlet; system pressure 45-50 psi
5 Pathways of Oxygen
- Flow to the fresh gas meters
- Powers the oxygen flush valve
- Activates failsafe valve
- Activates oxygen low pressure alarm
- Compresses bellows
Low Pressure Circuit Test
Checks from flow control valves to CGO. Place suction valve on CGO and squeeze till collapsed; must remain collapsed for 10 seconds or more. Also check for low pressure O2 alarm; check individual vaporizers for leaks
Oxygen Failsafe Shut Off Pressure
25-30 psi
Most are Proportioning Type (OFPD); drop N2O based on O2 PRESSURE not FiO2.
Located downstream of N2O source; shuts off or proportionally reduces N2O flow if O2 decreases to prevent hypoxia
PISS system configurations:
- O2
- N2O
- Air
- CO2
- Heliox
Pin Index Safety System
- 2,5
- 3,5
- 1,5
- 1,6
- 2,4
Bobbin Flow Types
- Low Flow: Laminar flow (diameter of channel < than length), so VISCOSITY is important
- High Flow: Turbulent flow, gas flowing around bobbin through orifice (diameter of channel > length) so DENSITY important
Oxygen Cylinder: contents and pressure
625-700L; 2000-2000 psi
First Stage Pressure Regulator: 1. O2 2. N2O Second Stage Pressure Regulator: 1. O2 2. N20
First Stage: 02: 2000 -> 45 N2O: 745 -> 45 Second Stage: O2: 45 -> 14 N2O: 45 -> 26
*N2O at higher pressure so that it flushes out of the system if there’s a leak
Low Pressure System (6 items)
Pressure slightly above atmospheric
- Flow Meter Tubes (Thorpe tube)
- Proportioning Links (Hypoxic Guard)
- Vaporizer
- Check Valves
- Pressure Relief Device
- Common Gas Outlet
- most susceptible to leaks; O2 ANALYZER only alarm in low pressure
- O2 always furthest right on tubes (downstream) to prevent hypoxic mixture if leak is present in N2O or Air tubes; won’t prevent hypoxic mixture if O2 tube leaking
- Hypoxic guard won’t allow mixture of O2 <25%
Oxygen Flush Valve flow rate
35-75 L/minCan cause barotrauma; only use during expiration
High Pressure System Components (5 items)
Pressure > 45 psi
- Cylinders (PISS)
- Cylinder Hanger yokes
- Yoke blocks with check valves
- Cylinder pressure gauge
- 1st Stage pressure regulator
Pressurized Air Cylinder: Contents and Pressure
Approx 625L; 1800 psi
Common Vaporizer Problems (7 items)
- Overfilling
- Contamination
- Wrong Agent
- Pumping Effect
- Tipping
- Leaks
- Administration of multiple vapors
Describe Minimal Sedation:
- Cognition
- Respiratory
- Cardiovascular
- Anxiolysis; Respond to comands; cognition and coordination may be impaired;
- Unaffected
- Unaffected
Describe Moderate Sedation:
- Cognition
- Respiratory
- Cardiovascular
- Conscious sedation; patients respond to commands either verbally or with tactile stimulation
- No interventions needed to maintain airway/ventilation 3. Cardiovascular function usually maintained
Describe Deep Sedation:
- Cognition
- Respiratory
- Cardiovascular
- Not easily aroused, responds to painful or repeated stimulation
- Airway protection and respiratory function usually impaired
- Cardiovascular function usually maintained
Describe General Sedation:
- Cognition
- Respiratory
- Cardiovascular
- Not arousable, even by painful stimulation
- Requires complete assistance maintaining ventilation/airway
- Cariovascular function usually impaired
Anesthesia Workstation Standards overseen by…
American Society for Testing and Materials (ASTM)
Machine Checks Should be done…
- Complete check every 24hrs
2. Circuit check between each patient
