Equipment Flashcards
What colour is oxygen pipe?
White
What colour is NO pipe?
Blue
What colour is air pipe?
Black
What colour is suction pipe?
Yellow
How should the ventilator RR be set for a healthy patient?
12
How should the ventilator tidal volume be set for a healthy patient?
6-8
What should the ventilator PEEP setting be for a healthy patient?
5
(4-10)
What should the ventilator peak inspiritory pressure setting be for a healthy patient?
<30 -32 cm H2O
What should the ventilator minute volume setting be for a healthy patient?
70-100 ml/kg
(Set according to production of CO2)
What should the ventilator inspiratory: expiratory ratio setting be for a healthy patient?
1:2
What should the ventilator plateau inspiratory pressure setting be for a healthy patient?
<25 -30 cm H2O
What should the ventilator endpoint sa02 (arterial hb saturation ) setting be for a healthy patient?
92-98
What should the ventilator endpoint Pa CO2 (arterial PCO2 in Pretoria) setting be for a healthy patient?
31-39
See picture 1 and describe capnogram
Normal end-tidal capnography waveform.
See picture 2 and describe capnogram
Crurare cleft: attempted inspiration during intubation. imply light level anaesthesia, muscle relaxant wearing off
See picture 3 and describe capnogram
“Shark fin” wave. Bronchospasm
See picture 4 and describe capnogram
Oesophageal intubation
See picture 5 and describe capnogram
Cardiac oscillations
See picture 6 and describe capnogram
Sudden decrease in cardiac output due to embolism of any substance in amounts that can obstruct right ventricular outflow (massive dead space ventilation) causes abrupt decrease in PET CO2. Also due to hypotension, cardiac arrest.
See picture 7 and describe capnogram
Increase in c02. Due to hypoventilation , increased production, hyper metabolic state. Eg due to sepsis, hyperthyroid, malignant hyperthermia
See picture 8 and describe capnogram
Baseline increasing. Sodalime exhausted or inspiratory/expiratory valves leaking
What can cause false reading on pulse oximeter? (7)
• Abnormal haemaglobin species eg methaemoglobin and carboxyhaemoglobin interfere with measurement of oxyhaemaglobin
• iv dyes eg methylene blue absorbs light at 660 nm and decreases spo2
• nail polish
• dark skin pigmentation may cause overestimation PAO2
• electromagnetic and electrocautery = artefacts
• ambient light = artefacts
• Movement = artefacts
• vasoconstriction: eg hypothermia = decreased amplitude
• low cardiac output
Advantages of circle system? ( 6 )
• Economical: less FGF and inhalation agent used
• pollution of theatre environment reduced (scavenging possible)
• inspired gases heated and humidified
• no rebreathing - absorb c02, sodalime
• use smaller diameter tubing to reduce dead space
• can measure inspiritory and expiratory gas concentrations
• best for maintenance
Label picture 9
A miller blade
B macintosh laryngoscope blade
Name 8 duties of anaesthestist during anaesthetic.
• Oxygenation status
• awareness prevention
• maintain correct plane of anaesthesia
• haemodynamic /respiratory monitoring and manipulation
• positioning
• ensure well-being perioperatively
• create optimal surgical conditions
• post-op pain management
Label picture 10
See picture 11
Name 4 functions of the anaesthetic machine
• provide oxygen
• accurately mix anaesthetic vapours and gases
• enable patient ventilation
• minimise risk patients and staff
Name 6 ways the anaesthetic machine prevents hypoxic mixture
• Oxygen analyser
• diameter index safety system
• pin index safety system
• international Color code
• proportional device - hypoxic guard
• oxygen Fail safe valve
Pressure gauge on cylinder and pipeline and will alert low pressure oxygen.
What colour is oxygen cylinder?
Black body, white shoulders
What colour is air cylinder?
Gray and black, white shoulders
What colour is carbon dioxide cylinder?
Green body, white shoulders
Name 4 components of the high pressure system of anaesthetic machine
Refers to cylinder and pipeline gas supply
. Check valve
• pressure regulator
• cylinder pressure indicator
• hanger yolk
Name 4 components of the intermediate pressure system of anaesthetic machine
Receive lower pressures
• pressure gauges (will alert to low oxygen pressure)
• common gas outlet
• oxygen flush
• oxygen pressure failure devices
Name 3 components of the low pressure system of anaesthetic machine
Pressure slightly above atmospheric. From flow control valves to gas outlet.
• flowmeters
• Vaporiser mounting device
• common gas outlet
Vaporizer function?
Convert liquid anaesthetic into Vapor and release controlled amount into fresh gas flow for maintenance of Anaesthesia eg sevoflurane
Name the 2 types breathing circuits and 2 main differences
• Rebreathing:mapleson a-f - high flows, flush out c02
• non-rebreathing: circle system - low or high flows, c02 absorber
Name 7 components of an anaesthetic circuit
•Efferent limb (from fresh gas outlet to patient, supply fresh gas )
• afferent (from patient) limb
• y-piece between efferent and afferent limbs
• volume of dead space (does not take part in c02 elimination)
• adjustable valve(s): heidbrink pressure release valve (rebreathing), airway pressure limiting apl valve or unidirectional ventilator valve. Allow venting of gas during spontaneous ventilation and determine gas flow direction during controlled ventilation.
• mechanism to eliminate CO2 from afferent limb (flow or chemical dependant)
• reservoir bag or ventilator.
Name functions of reservoir bag in anaesthetic circuit (3)
• allow for peak inspiritory flows during inspiration (up to 50 l/ min adults)
• assisted ventilation when valve partially closed
• give indication that patient is breathing, not if adequate
Name picture 12
Mapleson F breathing circuit
Name picture 13
Circle system non-rebreathing circuit
Name picture 14
Mapleson A breathing circuit
Name picture 15
Mapleson C breathing circuit
Name picture 16
Mapleson B breathing circuit
Name picture 17
Mapleson D breathing circuit
Name picture 18
Mapleson E breathing circuit
Describe mapleson A breathing circuit (inlet, valve, reservoir, tubing, other name) and use
• Fresh gas inlet near bag
• valve near patient
• reservoir bag present
• corrugated tubing present
• also called Magill
• used during spontaneous ventilation
Describe mapleson c breathing circuit (fresh gas inlet, valve, reservoir, tubing) and use (5)
• Fresh gas inlet near patient
• valve near patient
• reservoir bag present
• corrugated tubing absent
• not used in anaesthesia but similar to ambubag. Use when anaesthetic machine, piped gas or mechanical ventilator not available eg transport. Not for spontaneous ventilation. Used in emergency resus.
Describe mapleson D breathing circuit (inlet, valve, reservoir, tubing, alt name) and use
• Fresh gas inlet near patient
• valve away from patient
• reservoir bag present
• corrugated tubing present
• also called Bain circuit
• more efficient during controlled or manual ventilation. Spontaneous IPpV, general anaesthesia.
Describe mapleson E breathing circuit (inlet, valve, reservoir, tubing, alt name) and use
• Fresh gas inlet near patient
• valve away from patient
• reservoir bag absent
• corrugated tubing present
• also called Ayre’s t piece
• allow spontaneous breathing with addition of oxygen
Describe mapleson F breathing circuit (inlet, valve, reservoir, tubing, alt name) and use (6)
• Fresh gas inlet near patient
• valve absent
• reservoir bag present
• corrugated tubing present
• also called Jackson Rees circuit
• used for vapour induction and emergence in children and babies up to 20kg because made of very light plastic and low dead space. Controlled and spontaneous ventilation possible
What fgf needed for mapleson A?
Sv: 70-100 ml/kg/min (= to MV)
Ippv: min 3 X mv (but very high and difficult to predict)
What fgf (fresh gas flow ) needed for mapleson c?
Ippv: min 15 lpm - 2xMV
What fgf needed for mapleson d.
Sv: 150-200 ml/kg/min - 1-2x MV
Ippv: 70-100 ml/kg/min - 2-3 x MV
What fgf needed for mapleson f?
2,5-3 X mv (high)
Min 4 lpm
For both Sv and IPPV
What must be checked in machine checks? (7)
• gas supply
• back up oxygen cylinder
• flowmeters
• vaporizers
• oxygen flush
• ventilators
• circuit leaks
Label picture 19 a
See picture 19 b
What are the 5 things that need to be evaluated when interpreting capnography
•Is It present
• is baseline zero
• is alveolar plateau flat, value ideally 35-45
• Is petco2 rising with baseline zero
• Is petc02 decreasing over time
Describe and diagnose picture 20
Sudden disconnection or extubation; loss circulatory function
Describe and diagnose picture 21
Total obstruction eg lanyngospasm, kinking of ETT, or leak.
Describe and diagnose picture 22
Rebreathing circuit, or sodalime exhausted
Describe and diagnose picture 23
Tachypnoea
Describe and diagnose picture 24
Late emptying of lung regions eg pregnancy, obese
Describe and diagnose picture 25
Leak in system
Describe and diagnose picture 26
Sudden decrease cardiac output
Which graph shows the oximetry?
Plethysmogram
When should spirometer be used?
When use pressure control ventilation
Name 6 things spirometry indicates
• Tidal volume and rate (minute volume)
•Compliance
• airway resistance
• peak airway pressure
• plateau pressure
Contraindication non-invasive bp monitoring?
Av fistula
Name 4 indications invasive bp monitoring (arterial line)
• Sampling
• No NIBP
• fluid status
• pt risk with bp change
• large pressure and volume shifts occur
• renal function compromised
Name 4 contraindications arterial line bp monitoring
• av fistula
• no collateral
• bleeding tendency
• site infection
Name 3 complications arterial line bp monitoring
• ischaemia /thrombosis
. False aneurysm
• bleeding
What does CvP represent? (What is it)
Interaction between blood volume, venous tone, right heart function.
Normal CvP?
0-5 mm hg
Name 4 indications CVP
• fluid status (trend)
• drugs (inotropes, TPN, kcl)
• No lines
• treat venous air embolism
Name 4 complications CVP
• Structure injury
• failure/clotting
• Pneumothorax
• bleeding
What does nmT monitor?
Neuromuscular transmission device
Extent of muscle paralysis
Name 4 methods monitoring core temperature
• nasopharyngeal
• distal esophagus
• tympanic membrane
• pulmonary artery catheter: gold standard
Name 3 methods monitor depth of anaesthesia
• EEG
• bispectoral index (bis)
• entropy (type EEG with less monitors)
Target bispectral index value?
40-60 is adequate depth of anaesthesia.
100= awake, 0=n0 activity.
Label picture 60
See picture 61 (circle system)
Shape of nitrous oxide inlet?
Semi Circular
Shape of suction inlet?
Square
Shape of oxygen inlet?
Hexagonal
Name 5 advantages mapleson F breathing circuit
• low resistance, light weight, valveless
• can feel lung compliance
• ability to assist ventilation
• low dead space
• partial rebreathing heats and humidifies gas
Much faster induction! Then can switch to circle
Name 4 disadvantages mapleson F breathing circuit
• no scavenging, pollutes theatre
• need high fgf for sv, wasteful anaesthesia
• et c02 measurement inaccurate in < 10 kg
. Less efficient than circle
What is HME filter?
Heat and moisture exchanger
Increase dead space and resistance to circuit
Prevent damage, maintain mucociliary function
Name 10 items that must be available on the working area of the anaesthetic machine for airway management
Five metals
• laryngoscope
• Magill forceps
• stylet for tube
• artery forceps
• infusion stands
Five plastics
• face mask
• tracheal tube
• Guedel airway
• Airway filter
• suction tip
Pressure in full oxygen cylinder?
4 bar
Reaction of sodalime with CO2 produces what?
Heat and water
Name 5 components of a scavenger system
•Collecting system: from apl valve and ventilator at machine outlet
• tubing to transfer gas : from collecting system to scavenger interface
• scavenger interface: open with a reservoir or closed without reservoir but with relief valve
• gas disposal tubing
• gas disposal assembly: active (vacuum) or passive
Name 6 essential monitors intra-op
• Saturation
• capnogram
• non-invasive bp
• ECG
• temperature
• oxygen analysis
(Peripheral nerve stimulator)
How does et co2 on capnogram and arterial co2 on blood gas correlate? Significance if deranged?
Indicate adequate ventilation when et co2 and a cop are more or less the same
Low et co2: hyperventilation if ac02 also low. If a c02 high, there’s a problem with getting adequate c02 to the lungs to be exhaled due to low bp or lung diffusion problem
High: hypoventilation
Name 4 causes of no reading on capnogram
• Problem with monitor
• Misintubation
• complete disconnection or obstruction somewhere
• cardiac arrest
Name 3 processes reflected by the capnogram
• Metabolism: production co2 from 02 consumption
• transport: to the lung (BP/ flow )
• ventilation:gas exchange by removal c02.
Name 3 causes small wave form on pulse oximetry making the reading unreliable
• Vasoconstriction
• low cardiac output
• hypothermia
When use bis monitor?
Tiva
Because can’t monitor depth of anaesthesia using MAC and other measures with volatiles
Identify and describe pathology picture 75 as seen on arterial line.
See picture 76.
Swing- large difference in pulse pressure variation (difference between pulse pressures during positive pressure ventilation at inspiratory and expiratory times ) caused by change in preload eg dehydration
How calculate pulse pressure variation on arterial line?
Ppmax-ppmin/ pp mean x 100/1
What does a pulse pressure variation on arterial line of > 12% indicate during resus?
Will be fluid responsive so give fluid
What does a pulse pressure variation on arterial line of < 8% indicate during resus?
Not fluid responsive so give inotropes (8-12 grey area)
Name 3 disadvantage of the circle system
• Complex
• prone to leaks
• can’t be used outside of hospital (mapleson can)
Increase dead space x2
Volume vs pressure control ventilation? (4)
• Favours control of ventilation to ensure required mv vs oxygenation
• need healthy alveoli vs used in severe obstructive and restrictive lung disease
• set tidal volume (6-8 ml/kg) vs inspiratory airway pressure ( 8-12 cm h2o)
• variable inspiratory pressure vs variable tidal volume (dependent on resp compliance)
Name 3 advantages volume controlled ventilation
• Guaranteed tidal volume resulting in more stable minute volume.
• ventilator will alarm when inspiratory pressures too high >30
• initial flow rate lower than PCV so avoids high resistance related early pressure peak
Name 3 disadvantages volume controlled ventilation
• Very high inspiratory pressures may cause barotrauma
• alveolar recruitment may be poorer in poor compliance lungs
• mean airway pressure lower, which decreases oxygenation
Name 3 disadvantages pressure controlled ventilation
• Tidal volume may become very small if peak inspiratory pressures set too low, which causes hypercapnia
• obstruction in circuit or patient with decreased lung/chest wall compliance may go unnoticed → low tidal volume
• tidal volume may become very high in lungs with normal or high compliance → hypocapnia, volutrauma (overdistension)
• tidal volume variable and dependant on respiratory compliance
Name 3 advantages pressure controlled ventilation
• Lungs protected from high pressures, preventing barotrauma
• increased duration alveolar recruitment (alveoli opened earlier and remain open longer)
• work of breathing and patient comfort better
Name a condition where volume control ventilation is preferred
Traumatic brain injury: need tight paCo2 control with minute volume
Name 5 condition where pressure control ventilation is preferred
• Paediatrics
• lung Bullae
• one - lung ventilation eg thoracotomy
• severe obstructive and restrictive lung disease where there is decreased compliance
• LMA and uncuffed tubes (leak in circuit)
• preumo or haemothorax
Identify pathology picture 77
Decreasing et co2 due to:
• ETT cuff leak
•ETT in hypopharynx
• partial obstruction
Identify picture 82
Oxygen
Identify picture 83
Nitrous oxide
Identify picture 84
Carbon dioxide
Identify picture 85
Air
Identify picture 86
Entonox (50 % nitrous 50% oxygen)
Identify picture 86
Mapleson E / ayre t piece
See picture 87
Identify picture 88
Mapleson d/bain
See picture 89
Identify picture 90
Mapleson A / MaGill
See picture 91
Identify picture 92
Circle system
See picture 93
Identify picture 94
Oropharyngeal/ Guedel airway
Identify picture 99
Nasopharyngeal airway
