Equipment/Monitoring Flashcards
SSEPS/MEP nerves
SSEP- stimulation PT and ulnar n, transcranial signal recording of somatosensory cortex
MEP- Transcranial motor cortex stimulation, signal recording of CST (epidural/intrathecal D/I waves), Thenar muscles, Tib Ant- CMAPs.
Bite block!
Radiation Safety
Effects: Deterministic vs stochastic
Absorbed vs equivalent vs effective dose
Whole body effective dose should be < 100 mSv over 5 years, 50 mSv 1 year, 1 mSv during pregnancy
Principles
- ALARP- distance, time, shielding
- Education
-Audit/dosimetry
Level 2 check
High pressure system
- Wall
-Cylinder
Low pressure system
- Flow controls
- Vapourisers
- Breathing system- circle integrity, valves, hand bag, APL
- Monitoring (Gas analysis)
- Ventilator P/disconnect alarm
-Scavenging
-BMV
Other
- Airway equipment
-Suction
-IV/LA delivery devices
Final check
-Vapourisers off, purge
Document
Level Three Check
- Check vapouriser if it has been changed
- Check breathing system if changed
- Check IV or LA device
- Check other apparatus
POCUS Principles
General
- Trained practitioners
- Extension of clinical exam
- Can use multiple modalities
Conduct
Consent and clinical environment
Equipment and image qualitiy
Image storage and reporting
Structured training and supervised practice
Follow published guidelines
Paeds pocus is evolving
Machine Safety
High pressure circuit
Low Pressure circuit
Gas and vapour controls
Alarms
Antibump
Power
Maintenance/documentation
Cardiac Output monitoring
Direct Fick- VO2 meter/a line/PAC
Indirect Fick: VO2 assumed, CVC, a line
Thermodilution: PAC
Pulse Contour Analysis
- Calibrated: PiCCO- requires thermistor tipped A line + CVC
- Uncalibrated: Flotrach/Vigileo: Flow sensor arterial line
LiDCO: pulsed power analysis from
TOE
Thoracic bioimpedance
Gas rebreathing
EMG Spinal surgery
EMG
● Spontaneous/free-running EMG used to monitor selective nerve root function
● During cord instrumentation/pedicle screw placement radiculopathy is more likely than
SCI - making spontaneous EMG optimal for these procedures (continuous, no
stimulation required)
● At baseline - a healthy nerve root should have no/minimal activity
○ During surgery, irritation due to traction or thermal injury will result in spikes or
bursts (neurogenic discharges) proportional to the degree of injury (good
evidence base)
● Normally one muscle monitored per nerve root unless very high risk (e.g. C5 - where
deltoid and biceps may be used)
○ Advantages:
■ Highly sensitive for root injury
■ Provides constant feedback
■ May be combined with SSEPs to improve specificity
○ Disadvantages:
■ High false positive rate
■ Extremely sensitive to temp changes (cautery, irrigation)
■ Precludes NMBDs/affected by anaesthetic drugs as per MEPs
